NSIDC’s Dr. Walt Meier answers reader questions on sea ice

From Steve Goddard: Thanks again to Dr. Meier from NSIDC for answering questions, and for offering to do a follow-up.

From Anthony: Responses from Dr. Meier are in italics. I’ve added a poll that you can answer after reading this. Note this poll only allows one vote per IP address. So shared IP systems at offices will only get one vote.

From Dr. Meier: Thank you to Mr. Goddard for presenting this and the previous set of questions. And thank you to Mr. Watts for providing the outlet to publish these. I don’t hope to change the opinion of every climate change skeptic who reads my responses, but hopefully I can provide some useful for information. My answers here and to the previous round of questions are my own and I am speaking for myself, not as a representative of the National Snow and Ice Data Center or the University of Colorado. Thanks to Stephanie Renfrow, Ted Scambos, Mark Serreze, and Oliver Frauenfeld of NSIDC for their input.

One thing I noticed in the comments on my previous answers was a desire for references to peer-reviewed journals. I originally chose not because I didn’t realize there might be an interest and also because a few journal articles doesn’t substantiate human-induced global warming (nor do one or a few articles refute it). It is the preponderance of evidence presented in thousands of articles that provides the foundation for the human-induced global warming theory. Nonetheless, below I provide a few selected references for those that might be interested.

There were lots of good questions from readers, and I have synthesized some of them into a few short ones here for the sake of brevity. There is no question that late-summer Arctic ice extent has declined considerably since the early 1980s, and if the current trend continues linearly – the sea ice will disappear completely at some point in the not too distant future. Most of the questions were along the lines of “how do we know the trend is non-cyclical, and how do we know what is causing it?”

1. Q: The image below shows the general GISS temperature distribution of the previous Arctic warming cycle in the 1920s and 1930s, for stations north of 60N. Turquoise dots had warming similar to the current warming. Red dots are significantly warmer now than they were 70 years ago. Looking at the map, it would be easy to come to the conclusion that the only difference between the current warming and the one 70 years ago, is that the PDO has been in it’s warm phase for the last 30 years – causing warmer temperatures around Alaska and Eastern Siberia. The PDO appears to have recently shifted to its cool phase, and temperatures across Alaska have dropped during the last two years. Why do you believe that the fundamentals of the current warming are so different? Perhaps the warming of the last 30 years was aggravated by a coincidental alignment of the PDO and AMO?

A: The warming of the last 30 years cannot be attributed primarily to the Pacific Decadal Oscillation (PDO) or the Atlantic Multidecadal Oscillation (AMO). The AMO does not have a significant influence on the Arctic. On the Atlantic, side, the North Atlantic Oscillation (NAO)-a regional expression of the Arctic Oscillation (AO)-is the most influential mode of variability in the Arctic. As I’ve mentioned previously, there are natural variations in climate that do indeed affect Arctic temperatures in the Arctic and the sea ice. The NAO/AO is a particularly prominent one and a substantial amount of the decline in the sea ice during the late 1980s and early 1990s could be attributed to a strong positive mode during winters because the positive mode favors the loss of thicker ice that is less likely to melt during summer. However, since about 1995, the AO has mainly been in a neutral or negative state. Under such conditions, the Arctic sea ice should have started to recover. Instead, sea ice extent has not only continued downward, but the decline rate has accelerated. The AO may have been a “trigger” for the precipitous decline, but we wouldn’t have the ongoing decline without the documented warming trend (Lindsay and Zhang, 2005).

The Pacific Decadal Oscillation (PDO) also can play role in temperatures in the Bering Sea region and to some extent in the Pacific side of the Arctic Ocean. The PDO was in a fairly persistent positive mode until the mid-1990s, but it also has shifted to a more neutral state and so cannot explain the decline of the Arctic sea ice since that time. (More details: Overland et al., 2004 and Overland and Wang, 2005).

Another important point is that these climate oscillations can themselves be affected by global warming. There are indications that the positive mode of the AO is more likely to be present under warmer conditions.

2. Q: Given that we don’t really understand what caused the earlier warming period, what evidence is there that the current warming is anthropogenic? How much of your viewpoint about the Arctic future is based on IPCC feedback predictions?

A: There is considerable evidence that the current warming is anthropogenic; this evidence is readily available in thousands of unrelated peer-reviewed scientific journals. You also ask how much of the evidence is “based on” IPCC predictions? In a way, the answer to that question is that none of the evidence is from the IPCC report-and yet all of it is. The reason is that the IPCC report isn’t a source of newly published information, but rather a compilation of evidence from a growing number of articles previously published in scientific journals. All of the information in the IPCC working group reports is referenced to original peer-reviewed journal articles citing researchers from around the world. Thus, the IPCC report is a convenient “one-stop shop” of the latest information, but the ultimate source is the thousands of individual international journal articles that are the basis of the report.

In the first part of your question, you suggest that a lack of understanding of earlier warming periods is a given, and that this casts doubt on our understanding of current warming. From this perspective, it might seem reasonable to assume that because previous change was natural, the current change must be too. Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.

On top of the lack of evidence for natural causes, such suggested explanations ignore the proverbial elephant in the room. Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate. This, again, has not been addressed in a reasonable way.

Here is what we know about greenhouse gases and their influence on climate:

1. Greenhouse gases absorb energy radiated by the earth that otherwise would escape to space, keeping the earth warmer than it would be without GHGs. This is a fact that has been well-known for over 100 years, described in a paper by Arrhenius (1896). GHGs are a necessary part of Earth’s natural “climate control.”

2. GHGs are increasing in the atmosphere. This is known from observations of carbon dioxide dating back to the 1950s from Mauna Loa and other stations, as well as paleo-records of GHG concentrations in ice cores.

3. The GHG increase is due to human-caused emissions. This is clear from the simple fact that we know we’re emitting GHGs through our use of fossil fuels. More scientifically, it is confirmed by a characteristic chemical signature of human-emitted GHGs found in the atmosphere.

4. GHG concentration and surface temperature are closely linked. This is clear from #1, but the relationship is confirmed in ice core records dating back several hundred thousand years. Some of your readers may have heard a suggestion that carbon dioxide lags temperature in the ice core records; that’s not relevant in this case. For more details, see here and here and here

5. The first studies of the effect of GHGs on Earth’s energy budget date back to the1950s (e.g., Revelle and Seuss, 1957). The increasing GHG emissions have already changed Earth’s energy balance. Human and natural changes have increased the radiative forcing (effectively increasing the energy, and thereby the temperature, of the Earth) by about 1.6 Watts per square meter. The largest factor by far is human GHG emissions. Changes in the sun play only a small role. This increased radiative forcing results in a warming of the planet. There is simply not enough uncertainty in these estimates to throw the overall conclusion into doubt: human-induced GHGs have changed Earth’s energy balance and increased temperatures.

FAQ 2.1 Figure 2 from IPCC Working Group I Fourth Assessment Report, 2007.

6. There are feedback mechanisms that can alter the impact of GHG emissions. These include: clouds, water vapor, ice/snow. Ice and snow are clearly positive feedbacks that will reinforce the GHG warming because as they melt, the average albedo (reflectivity) of the earth decreases and more energy is absorbed. The effect of other feedbacks is less certain-and may even counter the effects of GHG warming–but the evidence indicates that they nevertheless do not come close to offsetting the direct effect of GHG emissions.

So, before one can suggest that natural mechanisms explain everything, one has to first demonstrate that something in the above 6 points is wrong. Much of this evidence dates back to at least the 1950s; the theory of anthropogenic global warming is really nothing new. Also note that climate models only play a significant supporting role in the evidence for points 5 and 6. No serious scientific study has yet shown that any of the above 6 points are fundamentally wrong.

The only one of the 6 points still in play to any scientific extent whatsoever is the last point. There has been some interesting research in this area – Richard Lindzen’s Iris effect (a nice summary here) and more recently Roy Spencer’s “internal radiative forcing.”. Spencer’s work is quite new, and has therefore not yet been properly vetted through the peer-review process. (Some informal discussion: RealClimate.

3. Q: You mention the historical record of the Inuit. What do we know about the older historical record from the Vikings?

A: There is archaeological evidence, oral sagas, and some written records, none of which I’m an expert in. However, I can share with you what I know: The Vikings colonized Greenland during about 700-1300 AD, taking advantage of the medieval warm period (MWP). There was reduced ice cover compared to before and after that period that allowed easier sailing between Europe and Greenland. The warmer climate allowed enough farming and ranching to support the population. As climate cooled, crops failed and transport (trade) with Europe became difficult or impossible. There was clearly less sea ice during the MWP than the cool period that followed. It is not known how sea ice conditions compared to today, but ice extents comparable to the 1980s or 1990s would have been sufficient for the Vikings to have successfully sailed between Greenland, Iceland, and Scandinavia; ice would not have had to be at current low levels.

Greenland and northern Europe were clearly warm during the 700-1300 AD; much of the rest of the globe may have been as well. There is often quibbling about whether we’re warmer now than then-the Mann hockey stick plot, etc. But as I pointed out above, such “debate” is almost beside the point: it ignores the elephant in the room that is the GHG emissions produced by humans. We may not clearly know what caused the MWP, but we have a clear cause for the current warming: human-caused GHGs.

4. Q: Is there any hard data on permafrost losses during the last ten years?

A: There is clear evidence of increasing ground temperatures and thawing permafrost, consistent with the warming surface temperatures. Permafrost will respond more slowly to warming, but it is a potentially significant long-term feedback because large amounts of GHGs, particularly methane, are “locked” in the permafrost. As much GHGs are locked in the permafrost as currently resides in the atmosphere. At least some of these GHGs will be released as the permafrost thaws. There have been several papers discussing permafrost thaw and potential climate impacts (Zimov et al., 2006; Lawrence and Slater, 2005; Lawrence et al., 2008).

5. Q: Has there been a trend of the date of minimum Arctic sea ice coverage? Has there been a trend in the date of maximum Arctic sea ice coverage? If there has been warming over the ice (which is not sampled adequately), there should be an earlier maximum and later minimum.

A: There has been a trend toward later minimum dates, but there is substantial variability from year to year in the freeze-up date. A later freeze-up is not surprising because with lower summer ice extent, there is more ocean area to absorb heat that needs to be dissipated before freeze-up can begin. However, there is high variability because the timing of when the ice stops shrinking and begins growing has a lot to do with short-term weather. A late-season warm spell can extend melt, while a quick, early cold snap can cut melt short.

There is essentially no trend in the date of maximum extent. There is even greater variability from year to year in the maximum date than in the minimum date. This is also not surprising. At the time of maximum extent, the boundary of the ice edge is unconstrained and has extended into the north Atlantic and north Pacific. Ice at the ice edge is also thinner at the maximum. Most of it is less than 50 cm thick, because it is ice that has recently formed. This ice is prone to being broken up by winds, advected into warmer waters where it melts, or pushed northward. On the other hand, cold winds from the north can cool surface waters and allow more ice to form, at least temporarily, and extend the ice edge farther south. So, the ice edge location at the time of the maximum is fairly volatile and subject to sudden change. This variability can be seen in AMSR-E data graph, where you can see the bumpiness of the daily extent during the winter season. This is the ice edge “bouncing around” in response to winds, currents, storms, etc.

6. Q: Looking at the AMSR-E sea ice extent graph, I see an alternative description for recent behavior. Until the first week in August, 2008 extent was equal to or greater than 2005 – and NSIDC was even considering a possible return to normal as late as August 1. However, a series of strong storms broke up the ice and caused 2008 to drop below 2005 for a few weeks. As September ends, 2005 and 2008 appear to be converging again. Average daily ice extent in 2008 has been greater than 2005, and nearly every day in 2008 has been greater than 2007. What is wrong with this description?

A: The description is incomplete and lacks relevant context. First, all the recent years in the AMSR-E record have had anomalously low maximum extents compared to the 1980s and 1990s. Even the largest winter extent, in 2002, was 250,000 square kilometers lower than the 1979-2000 average. The years 2005-2008 have been 700,000 to 1,000,000 square kilometers below the average. As described above, there is considerable variability during the time around the maximum extent, so the difference between 2005 and 2008 is within what might be expected from natural variations, but both are lower than maximum extents during the 1980s.

While there is a lot of variability in the timing of when the maximum occurs (as mentioned in #5), the actual maximum extent has relatively low variability. This is because in winter it is cold and dark, and ice grows under those conditions. So you always see ice growth, although there is now a significant downward trend at the maximum. In comparing winter ice conditions, ice thickness is much more relevant than ice extent. Data for thickness is not as complete as it is for extent, but it is quite clear that ice is thinning at a rate even faster than the extent decline. During winter 2008, the Arctic was dominated by seasonal ice (ice that has grown since the previous summer) that is much thinner than multiyear ice (ice that has been around for at least a year). Thus, in 2008 the ice has generally been thinner than 2007, and much thinner than earlier years.

We are now seeing some rapid growth of sea ice in the Arctic as the large expanse of exposed ocean cools, but this will all be thin first-year ice. It will thicken over the winter, but by the end of the winter it will only be a half to a third as thick as the ice used to be.

Sea ice also moves with the winds and currents – it doesn’t just grow and melt in place – and thinner ice is generally more easily pushed around. Last year a lot of ice got pushed by winds across the Arctic and even less of the region was covered by thicker old ice at the end of the winter than at the beginning of the winter.

Finally NSIDC did not say that the Arctic sea ice extent would return to “normal” in 2008. The figure referenced in the question, does show one scenario where ice returns to normal, but as stated in the text, that scenario was for a slower than normal melt through the rest of the summer and was deemed highly unlikely. As we say in our August 1 entry: “Thin ice is much more vulnerable to melting completely during the summer; it seems likely that we will see a faster-than-normal rate of decline through the rest of the summer.”

7. Q: Why does NSIDC say that the 2008 minimum sea ice extent “reinforces” the long-term trend when the 2008 extent was clearly higher than 2007?

A: 2008 is in no way a “recovery” relative to the thirty-year trend-and since GHGs act over long time periods, scientists favor looking at change over a long period to detect the GHG signal. From 1979 through last year, the September monthly average extent was declining at a rate of about 72,000 square kilometers per year based on a linear trend. Calculating a linear trend of the data from 1979 through 2008, the decline is now 78,000 square kilometers per year. This may seem counterintuitive, but what happens to the trend each time you add new data depends on where the new data falls relative to the trend line. If a data point falls below the trend line, it will “pull” the trend line downward; a data point above “pulls” the trend line upward. The September 2008 extent, although a bit higher than 2007, was still well below the trend line, so the downward trend line steepened. This is what I mean when I say the trend has been reinforced. Those who attempt to claim that we’ve seen “global cooling” since 1998 may wish to bear in mind that until scientists see a change over a long period, we are skeptical of claims concerning a trend.

The key thing, whether discussing sea ice, temperatures, or any other environmental measure, is to consider long-term trends, not short-term variability.

September monthly sea ice extent and trends for 1979-2007 and 1979-2008.

References:

Arrhenius, S., 1896. On the influence of carbonic acid in the air upon the temperature of the ground, Philos Mag, 41, 237-276.

Lawrence, D. M., A. G. Slater, 2005. A projection of severe near-surface permafrost degradation during the 21st century, Geophys. Res. Lett., 32, L24401, doi:10.1029/2005GL025080.

Lawrence, D. M., A. G. Slater, R. A. Tomas, M. M. Holland, C. Deser, 2008. Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss, Geophys. Res. Lett., 35, L11506, doi:10.1029/2008GL033985.

Lindsay, R.W., and J. Zhang, 2005. The thinning of Arctic sea ice, 1988-2003: Have we passed a tipping point, J. Climate, 18(22), 4879-4894, doi:10.1175/JCL13587.1.

Overland, J. E., M. C. Spillane, D. B. Percival, M. Wang, and H. O. Mofjeld, 2004. Seasonal and regional variation of pan-Arctic surface air temperature over the instrumental record, J. Climate, 17, 3263-3282.

Overland, J. E., M. Wang, 2005. The third Arctic climate pattern: 1930s and early 2000s, Geophys. Res. Lett., 32, L23808, doi:10.1029/2005GL024254.

Revelle, R., Seuss H.E., 1957. Carbon dioxide exchange between atmosphere and ocean and the question of an increase of atmospheric CO2 during past decades, Tellus, 9, 18-27.

Zimov, S.A., E.A.G. Schuur, and F.S. Chapin III, 2006. Permafrost and the global carbon budget, Science, 312, 1612-1613, doi:10.1126/science.1128908.


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252 thoughts on “NSIDC’s Dr. Walt Meier answers reader questions on sea ice

  1. I originally chose not because I didn’t realize there might be an interest and also because a few journal articles doesn’t substantiate human-induced global warming (nor do one or a few articles refute it).

    Actually it only takes one fact to refute it, and there are many.

  2. Oh, and the poll needs a fourth option: We don’t know enough to say if it’s natural or human induced.

  3. The key thing, whether discussing sea ice, temperatures, or any other environmental measure, is to consider long-term trends, not short-term variability.

    Not really, but at any rate, 30 years is not long term.

  4. re point #5:

    5. The first studies of the effect of GHGs on Earth’s energy budget date back to the1950s (e.g., Revelle and Seuss, 1957). The increasing GHG emissions have already changed Earth’s energy balance. Human and natural changes have increased the radiative forcing (effectively increasing the energy, and thereby the temperature, of the Earth) by about 1.6 Watts per square meter. The largest factor by far is human GHG emissions. Changes in the sun play only a small role. This increased radiative forcing results in a warming of the planet. There is simply not enough uncertainty in these estimates to throw the overall conclusion into doubt: human-induced GHGs have changed Earth’s energy balance and increased temperatures.

    We are just starting to see the effect of the diminished Solar output. The last century saw an increase in Solar activity to a “grand maximum” (probably not as grand as the MWP, but a maximum).

    If CO2 is the true culprit, we should see a continuing rise in temperatures. If not, we will see globally averaged temperatures flatten and/or reduce.

    cheers,
    Robert

  5. Dr Meier,

    Thank you for taking the time to answer these questions. It is appreciated. Many of your answers are quite clear, I feel the ones regarding the CO2 lag in the ice core could use some further explanation.

    The lag in CO2 in areas of high slope is the place I disagree with the standard explanation. The temperature in these areas clearly is well out of magnitude with the CO2 graph if the CO2 is to be believed is the causal factor. Claims that the CO2 was driving temperature seem highly flawed simply due to this portion of the graphs.

    As far as Real Climate links, I recently have discovered that CPS methods deamplify historic trends in the proxy based hockey stick data, despite repeated polite attempts to post, which were on topic for the thread my posts are deleted. If they cannot discuss the flaws in their math how can we accept their discussions on these other issues? — I apologize for the tone in this but it’s the truth!

    The HS math RC supports is flawed badly not just the PCA methods as demonstrated by CA but the CPS and after spending months studying the data I know we will soon discover the EIV method of M08 is equally flawed. RC refuses to even discuss the methods with the public. What’s more this means there are now three separate techniques which all “accidentally” find the same conclusion. After your third time it isn’t an accident any more.

    I arrived at my own conclusions independently of McIntyre and then found he and Ross had done similar work themselves. I will trust no post from Real Climate until they come clean about this critical issue!

  6. In that graph above, it shows water vapor as being far weaker than CO2 as a GHG. Water vapor is way more powerful than CO2 as a GHG (at least from every science source I’ve read).

    Could putting in the GHG value of water vapor in the stratosphere instead of the atmosphere be a marketing move by the IPCC so that CO2 looks powerful? Or am I overlooking or missing something here?

  7. As Dr. Keen points out, in 2007 Anarctica set a record most ice coverage while the Arctic set a record for least ice coverage (since 1979). This sea-saw temperature effect should not exist if CO2 were driving climate, but is consistent with Svensmark’s theory.

  8. You state: “2. GHGs are increasing in the atmosphere.”

    Recent evidence does show that the minor greenhouse gas CO2 is increasing. The most important greenhouse has H2O is commonly assumed to increase with increasing temperature due to CO2. I do not recall having seen quantitative evidence that H2O is increasing.

    Miskolczi has developed a climate model with a more accurate “semitransparent” planetary atmosphere rather than the conventional semi-infinite model. See: Greenhouse effect in semitransparent planetary atmospheres, Ference M. Miskolczi, Quarterly Journal of the Hungarian Meteorological Service, Vol. 111, No. 1 Jan-Mar 2007, pp 1-40
    Miskolczi’s model shows a constant optical depth as a result of energy minimization principles.

    Roy Spencer notes that precipitation trends are little known compared to the assumed increase in relative humidity with increasing temperature. See Global Warming and Nature’s Thermostat He has found some H2O positive feedback assumptions to in fact be negative.

    Do you know of any publications and methods that distinguish and quantify the trend in global H2O, and in the total optical depth of the atmosphere compared to just the CO2?

  9. Meier:
    Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.
    Evidence can only be lacking for specific causes, like ‘the sun’ or ‘cosmic rays’, but not for unspecified ‘natural variability’.

  10. Dr, Meir is a good salesman, but there is nothing new in this. It is obvious that he is an unconditional believer in AGW, to the point that all facts must bend to the AGW theory or be considered irrelevant because of the “elephant in the room”. As an example take this one citation from the interview:

    “it is confirmed by a characteristic chemical signature of human-emitted GHGs found in the atmosphere”

    Should we understand that scientists can ascertain that one carbon dioxide or methane molecule is natural and another is man-made?

  11. How many times does he have to say there is an elephant in the room? I guess his elephant is right in front of him and he can’t see what is IN the room!!!

    [snip, over the top ~ charles the moderator]… the earth is cooling down and we were not responsible for the last warming period, nor the next one.

  12. I have to say that it’s nice having someone from “the other side” (and an actual scientist to boot) treating us politely & as intelligent people. Who knows, if there was more discussions like this, I might be less skeptical about AGW…

  13. The best Dr. Meier could come up with to explain the 800-year lag between temperature and C02 (with C02 always following temperature in the ice-core record) were three weak web links, typified by the following quote from RealClimate. It is from Jeff Severinghaus of Scripps Institution of Oceanography.

    “The reason has to do with the fact that the warmings take about 5000 years to be complete. The lag is only 800 years. All that the lag shows is that CO2 did not cause the first 800 years of warming, out of the 5000 year trend. The other 4200 years of warming could in fact have been caused by CO2, as far as we can tell from this ice core data.”

    That’s the science that Meier is standing on.

  14. Do AGW-believing scientists really think that the tiny error bars for “long-lived greenhouse gasses” on the IPCC radiative forcing chart above are defensible? Given that the effect is more from feedbacks than from the direct impact of the gasses themselves, and that there is a laundry list of feedbacks both positive and negative, I do not find them credible. Reasonable, educated, intelligent people can debate AGW. I can’t imagine a reasonable, educated, intelligent person who would vouch for that chart.

  15. I’d like to thank Dr Meier for taking the time and effort to participate in this dialogue and hope his example will be followed by other climate scientists.

    One thing that immediately jumps out to me in his responses is the reply to question 2, part 6 where he says:-

    6. There are feedback mechanisms that can alter the impact of GHG emissions. These include: clouds, water vapor, ice/snow. Ice and snow are clearly positive feedbacks that will reinforce the GHG warming because as they melt, the average albedo (reflectivity) of the earth decreases and more energy is absorbed. The effect of other feedbacks is less certain-and may even counter the effects of GHG warming–but the evidence indicates that they nevertheless do not come close to offsetting the direct effect of GHG emissions.

    Note he says ice and snow are clearly positive feedbacks but does not includewater vapour in this category. But I thought the supposed positive feedback of water vapour was central to CO2 forcing. Is this still the case or has the message shifted to nothing can offset the direct effect of GHG emissions?

  16. Has Dr Meier ever taken a course in Basic Logic? For example:

    “The warming of the last 30 years cannot be attributed PRIMARILY to the Pacific Decadal Oscillation (PDO) or the Atlantic Multidecadal Oscillation (AMO). The AMO does not have a significant influence on the Arctic. [emphasis added]”

    The first proposition, with that crucial qualifier ’primarily’ is not categorically negative; it would allow for the PDO and AMO being secondary ‘attributables’. But the second proposition IS categorical and does not follow; in fact, it contradicts the first, unless secondary attributes are always to be dismissed as automatically ‘insignificant’.

    “The PDO was in a fairly persistent positive mode until the mid-1990s, ….”

    So the PDO was in the negative mode during the Great El Nino of 1998?

    ‘There are indications that the positive mode of the AO is more likely to be present under warmer conditions’

    Warmer conditions where? Doesn’t the positive AO lock in the coldest hemispheric air over the pole?

    “You also ask how much of the evidence is “based on” IPCC predictions? In a way, the answer to that question is that none of the evidence is from the IPCC report-and yet all of it is.”

    This is simply incoherent.

    “Thus, the IPCC report is a convenient “one-stop shop” of the latest information,….”

    Sort of like grabbing a bagel and with a shmear and the __Wall Street Journal at 7/11 .

    “Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate. ‘

    1. Human beings do not ‘cause’ greenhouse gasses; they are ‘caused’, or their attributes and effects are caused, by the laws of physics.

    2. No one can prove a negative (outside of pure mathematics), and besides, the question was about past climate change. Must any account of, say, the Holocene Optimum demonstrate that it was not caused by
    anthropogenically-produced GHG’s?

    “The key thing, whether discussing sea ice, temperatures, or any other environmental measure, is to consider long-term trends, not short-term variability.”

    What, in the time-frame that is relevant to geophysical processes, is a ‘long-term trend?’

    How about a million years?

  17. Anthony,

    Assuming Dr. Meier will do this again, please ask him to address Dr. Stephen Schwartz’s (of BNL) “Heat Capacity…” report, published last December, which essentially says that dobling CO2 from current levels would likely increase global temps 1.5 Deg K.

    Please reply if you need me to provide more info about it.

    GW

  18. “However, since about 1995, the AO has mainly been in a neutral or negative state. Under such conditions, the Arctic sea ice should have started to recover.”

    Everything I can find about this contradicts this statement. Of course one needs to know what “mainly been in a neutral” and “mainly been in a negative” state at the same time might mean. It seems at best that there have been some neutral periods, some positive periods and some negative periods, but no “mainly” trend, so as to reinforce the concept that the Arctic should have “started to recover” as a result.

    Here’s one example, although I don’t know where they got the graph from:

    There sure looks like a lot of positive state AO from 1995 on, and a massive positive AO trend from 1988-1995, incidentally when the Arctic started down. That *would*, by Meir’s reckoning, mean that the Arctic “should have” started to *decline*.

    The downplay of the PDO is also interesting to hear.

  19. According to Dr. Meier, only the long term trend counts. Fine, but reliable satellite data exist only for 30 years. That is the duration of the warming trend – sofar. Before that, there was a 30 years’ period of cooling, and before that, another 30 or so years’ period of warming in the global temperatures. Are there any proxy data which one could use to reconstruct the sea ice extend of the 1920′s and 1930′s?
    I would assume, the Bering strait was under surveillance since the early twentieth century. It is covered with ice around December 1, in general earlier in cold periods and later in warm ones. Dr. Akasofu in his paper:’Is earth still recovering from the little ice age?’ presents data from arctic stations and from isotope analysis of ice cores (Fig. 3a) which all indicate a very warm period in the 1930′s. So does Prof. Humlum in his website climate4you.

  20. I wonder if Meier has ever thought about the possibility that all those thousands
    of peer reviewed studies of AGW were based on flawed data or analysis. He refers to the body of evidence through the thousands of scientists who have found GHG made by man as the prime force for AGW. To me its the Pied Piper effect.

    His analysis for trends is incomplete. Yes there is a trend line, and at some point if other forces other than AGW are to prevail this trend line will be crossed. Will he then reverse his opinion or in the case of chart analysis revise his opinion to a new trend being established to the upside?

    None of the answers he gives are based on his own analysis, rather he relies on what others have found or what some one else has given for analytical breakdown. He has cut himself off from other data and forces which may affect ice growth and melt.

    Meier represents a systemic breakdown in the scientific community which has cut off its own ability for independent cognitive analysis based on what everybody else is thinking and not what all scientific data may have to represent relative to atmosheric forcing. I don’t care if he is protective of funding sources or not. Its obvious, Meier relies on the “Herd” mentality when responding to these questions. It is a sad day when someone with so much intellect loses his own ability or will to think for himself.

  21. Changes in the sun play only a small role? I guess time will tell us the truth on this one.

    Who will make India and China lower CO2 emissions? Looks like Obama / Pelosi and Reed will in the US. Not that it matters much for the USA anyway.

    From bondage to spiritual faith;
    From spiritual faith to great courage;
    From courage to liberty;
    From liberty to abundance;
    From abundance to complacency;
    From complacency to apathy;
    From apathy to dependence;
    From dependence back into bondage

    We are in step 7 or the 8 listed here.

  22. Still a skeptic. I expect that the next few decades should prove most enlightening, especially if temperatures drop significantly while China emits ever higher levels of CO2 and worldwide levels of GHG’s continue to increase.

  23. A very informative discussion that is much appreciated. Balanced dialogue is refreshing. As with most natural systems, climate issues are complex, and contributing factors varied and interrelated. As a biologist It seems apparent that complex natural phenomena are rarely caused by a single force.

    Thanks
    Jd

  24. Anyone ever thought this guy is just wasting your time. You’ve got loads of irrefutable science on this site. You don’t need loads of lies to know they’re wrong. We are definitely cooling don’t let the doublethink alter you. I know of loads of people from nutritionists to skeptic scientists who have campaigns against them specifically designed to waste their time. The whole piece was like a blur in the thread of clear and concise truth. All I want is the facts. We don’t need the bull. Ed.

  25. My name is Evert Jesse and I am following this fascinating debate for about a year now. I would like to comment on point 4) and 5). Point 4), the fact that CO2 lags the temperature in the ice core data, is in my opinion very weakly addressed, despite the confident tone. CO2 did not start the temperature rise, and water vapour is a much more powerful greenhouse gas than CO2; therefore the contribution of CO2 to the ice ages could in my opinion only be minor. They may need CO2 to fit their models, but that may just as well show that the models are not yet quite perfect. BTW notice the wording: “some may have heard a suggestion..” Original reports of the vostok ice core data are available on internet, they are dated 1999, and the summary clearly states that CO2 lags temperature. I would feel happier about the objectivity of dr. Meier if he had just acknowledged this as fact.

    Point 5) is interesting, because of the large uncertainty margin given: the radiative forcing could have been between 0.6 and 2.4 according to the shown figure from AR 4. The elephant in the room could therefore easily be Dumbo, leaving lots of room for other, natural causes. (or a mammoth, in which case the whole analysis would also be in question)

    This is something I noticed earlier: also the hockeystick in its original, not yet debunked form showed enough uncertainty margin to hide a minor ice age and MWP. The climate models show this margin of uncertainty of a factor 4, but because the averages of both met in the middle (or were tuned to meet)this was considered sufficient proof of human dominance in global warming.

    By now also the IPCC recognises at least the LIA, admitting thereby implicitely (but definitely not explicitely) that there are natural causes of temperature rise which have not been included in the figure above.

    Evert

  26. It seems to be like in the stock market: Those sticking to the 200day moving average (long term) miss the turn around, the bottom or the top. But those who stick to the 20day moving average (short term) catch those turning points, but get in and out of the market during longer trends.

    So the 30 year long term thinkers will miss a turnaround in ANY case. They have no chance. Therefore ignoring the possibility of a turnaround is a tactical fault. Underpinning this thinking with questionable (consensus, “There is considerable evidence that the current warming is anthropogenic; this evidence is readily available in thousands of unrelated peer-reviewed scientific journals.”) results is a fault in scientific thinking – no excuse.

  27. One important aspect might be missing from the discussion, black carbon. Estimates vary about it’s importance, but a 2007 study by Flanner et al (in JGR 112) is the basis for an article in Scientific American that black carbon (BC) could be the cause of up to 94% of Arctic warming:

    http://www.sciam.com/article.cfm?id=impure-as-the-driven-snow

    Because it is dark, when BC falls on snow or ice, it changes the albedo to absorb light as heat, rather than reflect it. Thus Asian BC (mainly from residential use of biomass and coal for heating and cooking, and from poorly controlled diesels) causes ice and snow to melt faster, which in turn reveals dark water which absorbs even more heat.

    Ramanathan and Carmichael (Nature Geoscience, 2008) find that BC may be the second most important anthropogenic emission, next to CO2, partly because of the effect on Arctic ice and snow.

    A 2004 paper by James Hansen and Larissa Nazarenko (PNAS) finds that up to 25% of the warming since 1880 may be due to BC, again partly due to its effects on melting Arctic sea ice:

    http://www.sciam.com/article.cfm?id=soot-more-culpable-in-cli

    It would be interesting to get an understanding of the extent to which Arctic sea ice would have melted the last two decades if there had been no or minimal Asian BC emissions. I’m not prejudging the answer, but the referenced papers make the question a reasonable one with regard to Arctic sea ice and temperatures, don’t they?

  28. I don’t hope to change the opinion of every climate change skeptic who reads my responses, but…

    Well then I’m sure the good doctor won’t mind if we call his side AGW zealots right? Seriously, the first words out of his mouth are both arrogant and denigrating. This is not in the tone of scientific discourse but rather the self appointed upper caste laughingly tolerating the untouchables begging for scraps from the back door.

    There is often quibbling about whether we’re warmer now than then-the Mann hockey stick plot, etc. But as I pointed out above, such “debate” is almost beside the point:

    Your opinion doctor is noted with context. I mean really. It isn’t quibbling and it isn’t ancillary. You don’t have a model that addresses the data. It isn’t the data in question it is the model.

  29. If you look at the infrared spectra for water, methane and CO2 ( http://www.college-cram.com/study/globalwarm/presentations/1071 ) it is clear that water (from its spectrum and concentration) is the most potent greenhouse gas in the atmosphere.

    In the graph of solar radiation forcing, water vapor does not count in the natural processes???!!! Can you find crackerjack science in those boxes now?

    It’s obvious that the solar activity has the greatest impact on the global climate. Taking in consideration both infrared spectrum and atmospheric lifetime of water in the atmosphere, I think we could start wondering if in fact, the temperature of surface water increased during high solar activity since the water in the atmosphere would absorb the energy from the sun and basically bring it down, in part, to the ground (or ocean) when precipitating.

  30. I voted for a combination. We know for sure that soot and ozone have significantly warmed the Arctic.

    Next year will be an important year. We have an early freeze, negative PDO and solar minimum. If the ice doesn’t recover, then it will be clear that something else is going on. If we do see a significant recovery, it will be difficult to make the case for an imminent meltdown.

  31. “We may not clearly know what caused the MWP, but we have a clear cause for the current warming: human-caused GHGs.”

    Although I am in the peanut gallery, I think I understand what he means. It doesn’t matter what caused the MWP, it is clearly not causing the warming today. And because we don’t know what caused the MWP it certainly couldn’t be whatever it was because we get lots of money to know so we have to know and can’t consider what we don’t know. Ya know?

  32. The elephant in the room appears to go right over Dr Meier’s head. We don’t know why the Medieval warm period was as warm or warmer then today, but with a little bit of handwaving we are sure today’s warmth is due to CO2. I am sorry but he has added nothing to this debate.

  33. The CO2 goes up and down approx 800 years after temperature.

    Yes, and then the std explanation:

    “The reason has to do with the fact that the warmings take about 5000 years to be complete. The lag is only 800 years. All that the lag shows is that CO2 did not cause the first 800 years of warming, out of the 5000 year trend. The other 4200 years of warming could in fact have been caused by CO2, as far as we can tell from this ice core data.”

    1) This is a hypothetical claim most certainly not supported by the curves
    2) AND VERY IMPORTANT:
    It ONLY explains how CO2 lags temperatur when turning UP.
    It does NOT explain how CO2 lags temperature when tuerning DOWN.

    The explanation does NOT deal with the fact that TEMPERATURE GOES DOWN 800 YEARS BEFORE CO2.

    Mr Meirs, explanation that CO2 drives temperature does not explain why temperature can just go down while CO2 is still climbing, and then 800 years after, CO2 follows down:

  34. Edward M., you write “we are definitely cooling”. And you’re saying that any evidence to the contrary of this “truth” is “doublethink”..and “bull”?
    This certainty is admirable, but difficult to accept in context of science-based conversation; just tiresome.

    Jd

  35. 6) Feedback.

    Can Mr Meir explain how feedback workd today when facts are:

    1) In the last dacedes the water content in the atmosphere is slightly decreasing
    2) Methane concentration in the atmosphere has stagneted many years ago.

    Feedback should be that the water or methane primarly there should be as a result of more CO2-heat should have an effect.

    How can they believe there is an effect from more water and methane when there is no more water and methane in the atmosphere?

    ?

  36. However, since about 1995, the AO has mainly been in a neutral or negative state. Under such conditions, the Arctic sea ice should have started to recover. Instead, sea ice extent has not only continued downward, but the decline rate has accelerated.

    But the NAO has been extremely positive over this period.

    On the Atlantic, side, the North Atlantic Oscillation (NAO)-a regional expression of the Arctic Oscillation (AO)-is the most influential mode of variability in the Arctic.

    … and, as you said yourself, the NAO “is the most influential mode of variability in the Arctic.”

  37. “A: There is clear evidence of increasing ground temperatures and thawing permafrost, consistent with the warming surface temperatures. Permafrost will respond more slowly to warming, but it is a potentially significant long-term feedback because large amounts of GHGs, particularly methane, are “locked” in the permafrost. As much GHGs are locked in the permafrost as currently resides in the atmosphere. At least some of these GHGs will be released as the permafrost thaws. There have been several papers discussing permafrost thaw and potential climate impacts (Zimov et al., 2006; Lawrence and Slater, 2005; Lawrence et al., 2008).”

    I had to read all the comments, to ensure that this had not been previously addressed. . .

    Perhaps the good doctor (sorry, Isaac), would be kind enough to explain how these GHGs managed to get locked into the permafrost in the first place.’

  38. Trying to word this carefully: Having studied the issues in scientific, economic, and sociological depth, I believe that anthropogenic increases in atmospheric CO2 should not concern us — and no money or resources should be spent trying to limit them (“all” things globally considered). My position does not rely on negating everything believed or espoused by the “pro global warming, anti-CO2 camp”.

    Given my belief, I think Dr. Meier is an excellent spokesperson for the “pro global warming, anti-CO2 camp” because his style is not off-putting and he answered questions clearly/thoroughly (given the response-length limitations of the media). Moreover, he gave sources and pointed out areas wherein his expertise is modest.

    I believe what he writes regarding sea ice is consistent with current scientific knowledge as viewed from a perspective shared by many scientists. I am happy to read such a clearly espoused position — from either side of any issue.

    Thanks to “Watts…” for publishing it.

  39. I find this comment very interesting:
    ““Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate. ‘”

    Why is the reverse not true?
    “Any AGW-based causes/explanation must be accompanied by an arguement for why and how naturally occuring GHGs are not affecting climate in the same way that AGW-GHGs affect climate.”

    Just askin’…

    Jim

  40. Leif Svalgaard (13:31:04) :

    Meier:
    Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.

    “Evidence can only be lacking for specific causes, like ‘the sun’ or ‘cosmic rays’, but not for unspecified ‘natural variability’.”

    Yet the sun and cosmic rays aren’t themselves causes, they are objects, and Meier didn’t say “unspecified” natural variability had been investigated.

  41. Like the Fly, the table became malformed in the transfer.
    ————————————————————-
    “There is considerable evidence that the current warming is anthropogenic; this evidence is readily available in thousands of unrelated peer-reviewed scientific journals.”

    It would be appropriate if Dr. Meier would present just one of the thousands of readily available unrelated peer-reviewed scientific journals as irrefutable factual evidence of anthopogenic global warming/climate change. There more than 31,000 American scientists who disagree with this conclusion.
    ————————————————————-

    “On top of the lack of evidence for natural causes, such suggested explanations ignore the proverbial elephant in the room. Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate.”

    This argument is irrelevent in the absence of any scienfic data showing that GHGs as a whole are responsible for the claimed effect on climate.
    ————————————————————-
    Note: I am not arguing against climate change. The climate is always changing. Only the IPCC, Al Gore and acolytes have decided that the climate has reached, or is in, its ideal state and that human intervention can control that change. Delusional people with a god-complex.
    ————————————————————-
    “GHGs are increasing in the atmosphere. This is known from observations of carbon dioxide dating back to the 1950s from Mauna Loa and other stations, as well as paleo-records of GHG concentrations in ice cores.”

    This is borne out by data from the DOE dated October, 2000.
    TABLE 1.

    The Important Greenhouse Gases (except water vapor)
    U.S. Department of Energy, (October, 2000) (1) (all concentrations expressed in parts per billion) Pre-industrial baseline Natural additions Man-made additions Total (ppb) Concentration Percent of Total
    Carbon Dioxide (CO2) 288,000 68,520 11,880 368,400 99.438%
    Methane (CH4) 848 577 320 1,745 0.471%
    Nitrous Oxide (N2O) 285 12 15 312 0.084%
    Misc. gases ( CFC’s, etc.) 25 0 2 27 0.007%
    Total 289,158 69,109 12,217 370,484 100.00%

    I have posted information before showing that after that date, all CO2 contributions to the atmospheric concentration were considered to be anthropogenic, although the IPCC report says that natural CO2 emissions are 30 times those of anthopogenic origin. It is said that the natural CO2 emissions are in balance with Nature and anthropogenic CO2 creates an imbalance – a violation of Nature.

    ————————————————————-
    The GHG increase is due to human-caused emissions. This is clear from the simple fact that we know we’re emitting GHGs through our use of fossil fuels. More scientifically, it is confirmed by a characteristic chemical signature of human-emitted GHGs found in the atmosphere.

    Saying that GHG increase is due to human-caused emissions does not make it true.
    ————————————————————-
    Note: To really get out-of-bounds, I believe that “fossil” fuels is a misnomer. I believe petroleum to be abiotic, as is the petroleum on the surface of Saturn’s moon, Titan.
    ————————————————————-
    What is the characteristic chemical signature of human-emitted (as opposed to car-emitted, aircraft-emitted, naturally-emited etc.?) GHG? Anthropogenic 12C is the same as “natural” 12C.

    Fossil fuels contain practically no carbon 14 (14C) and less carbon
    13 (13C) than air.

    The unstable carbon isotope 14C or radiocarbon makes up for roughly
    1 in 10**12 carbon atoms in earth’s atmosphere.

    The stable isotope 13C amounts to a bit over 1 % of earth’s carbon,
    almost 99 % is ordinary 12C [Butcher, p 240]. Fossil fuels contain
    less 13C than air, because plants, which once produced the precursors
    of the fossilized organic carbon compounds, prefer 12C over 13C in
    photosynthesis

  42. Thanks Dr Meier for the answers and explanations. I appreciate that you go out of your way to explain why global warming has a human cause. Usually we are told that, but the explanation as to how or why is usually not there. Usually its pretty much an instruction.

    The difficulty I have with your explanations however is they appear to revolve around a single point: that because man is increasing CO2 and other greenhouse gases, and because these greenhouse gasses are known to be the reason for the greenhouse effect, an increase in them MUST be the cause of global warming, and this “extra” global warming MUST therefore be the cause of current phenomena such as reduced artic ice.

    Its a very logical argument, but its not proof. Where I have real difficulty with it is, if true, why doesn’t the same thing appear to be happening in the Antarctic? Cyclical variations driven by the various Pacific and Atlantic oscillations are consistent with both historical fluctuations in Artic conditions and dissimilar conditions to the Antarctic. General global warming caused by man-made CO2 is inconsistent with historical fluctuations and the differences between the polar regions.

    Could I suggest next time that any discussion needs to include a reconciliation between the artic and antarctic conditions, and explanations need to explain both simultaneously, not in isolation.

    A great deal of research in recent years has greatly broadened our knowledge of what drives climate, and it also provides a glimpse of how much we don’t know. Given that, it seems we have backed the “CO2 is the cause of all evil” line a bit too hard and a bit too early .

  43. Dr Meier’s answers are part of the evolving AGW liturgy, reconciling natural phenomena with the AGW belief system. He has to do this to keep his job. If you want to see something really amusing, have a look at another use of US tax dollars: http://public.ornl.gov/face/results/figure2.shtml

    Growing plants under elevated CO2 levels is easy to do and there are hundreds of such studies. But the results are highly inconvenient. They show a wonderful benefit, including a 74% increase in biomass in one forest over six years. The solution the warmers came up with was to concoct a future with elevated ozone levels as well. Poison the forests with ozone and the results don’t look so good.

  44. “On top of the lack of evidence for natural causes, such suggested explanations ignore the proverbial elephant in the room. Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate. This, again, has not been addressed in a reasonable way.”

    This makes his position seem circular … It has to be man made because it can’t be natural because the man-made case wasn’t disproven.

    If we’re going to spend trillions of $, the burden should be on AWG.

    MikeEE

  45. “We may not clearly know what caused the MWP, but we have a clear cause for the current warming: human-caused GHGs.”

    Ok, Dr Meier, so you don’t know what caused previous warm periods but you are certain about this one? I think that says a lot.

  46. Mans CO2 emissions are 3-4% of global emissions. CO2 atmospheric levels are dictated by global ocean temperatures. As temperatures increase, so do CO2 levels. And how is mans 3-4% of CO2 entirely responsible for the rise in CO2 (in fact, half of our emissions are missing in action).

    Our only energy source is the sun. The IPCC by it’s own admission states it’s level of understanding of the sun on climate is low. GHG’s are not a source of energy, they slow down the release of energy to space. Water is the most important GHG, which is why in the deserts it still gets cold so quickly in the evening despite CO2 being at such high levels.

    I would be interested in knowing his views of the following periods of Climate Change where CO2 levels were much lower.

    http://www.iaea.org/programmes/ripc/ih/volumes/vol_one/cht_i_01.pdf

    ” 14000-8000 BC: end of glaciation; sudden and strong temperature fluctuations

    8000-6000 BC: rapid warming and melting of mountain glaciers; humid environment in the Middle East and savannah conditions in the Sahara

    5000-3500 BC: Post-Glacial “Climatic Optimum”: summer temperatures in NW Europe 2-30C above that of the present day; monsoonal rains penetrate the Sahara; extensive irrigated agriculture in Mesopotamia

    3500-1000 BC: drying of the Sahara (3500-1000); desertification and salinisation in Mesopotamia, Nile flow reduced; sharp decline in temperature about 1500 BC with a strong advance and initiation of new mountain glaciers (it has been suggested that the latter cooling might be connected with the huge eruption of the Santorin volcano in the Aegean Sea about 1450 BC)

    900-300 BC: Iron Age Epoch: Cool and wet in northern areas; strong regrowth of bogs after a much drier period

    400-800 AD: severe North Sea floods; growth of Alpine glaciers

    800-1200 AD: Secondary (Early Medieval) Climatic Optimum: summer temperature at least 10C above present day; drier in NW Europe; Viking colonisation of Greenland

    1430-1850 AD: Little Ice Age (polar continental climate): cool in W. Europe and the Mediterranean; temperatures 1-30C lower than at present; re-advancement of mountain glaciers; severe winters

    1850 AD -present: maritime Atlantic climate; global temperature rise 0.50C; N.Atlantic sea surface warmer; increased rainfall in NW Europe.”

    I would also like to know which are the top 10 most convincing articles that provide the basis for the theory that it is Anthropogenic CO2 causing climate change. I do not deny there is climate change, I just have not read anything very convincing that shows it is due to mans CO2 alone. I have also not been convinced that the climate change or warming that we have seen is a bad thing, as it seems that based on history, another ice age should be in the cards. That would wipe out 80% of mans population, same as the doomsday scenario of out of control warming envisioned by those who believe there are no negative feedbacks in our climate.

  47. I am speaking for myself… Thanks to Stephanie Renfrow, Ted Scambos, Mark Serreze, and Oliver Frauenfeld of NSIDC for their input.

    The result of this “groupspeak” is unconvincing to this reader. It would have been nice to hear the real thoughts of one real man.

    Mike Bryant

  48. Leif Svalgaard (13:31:04) :
    Meier:
    Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.
    Evidence can only be lacking for specific causes, like ‘the sun’ or ‘cosmic rays’, but not for unspecified ‘natural variability’.

    well said

  49. Water is the most important GHG, which is why in the deserts it still gets cold so quickly in the evening despite CO2 being at such high levels.

    I remember shivering at night in my Army-issued sleeping bag at Ft Irwin (Mojave desert) in August, 1983

  50. Dr. Meier is very kind to take time to offer answers for the questions. If he decides to do another Q&A round then I’d like to pose the following:

    Over the last 50 years the instruments used to estimate Arctic ice have changed. I also believe that the methods and assumptions used to interpret the instrumental data have been modified over time. My question is, how are the results from the various instruments and methods combined (spliced?) over the period of record so that the time series gives apples-to-apples results?

    A literature citation would be sufficient, as the answer to the question is probably a long one.

    Thanks

  51. Has Lewis Pugh made it to the North Pole yet? Someone told him that it is going to be ice free this year.

  52. Glenn (16:36:49) :
    Yet the sun and cosmic rays aren’t themselves causes, they are objects, and Meier didn’t say “unspecified” natural variability had been investigated.
    It is plain that ‘the sun’ etc was meant as a shorthand for a cause or explanation, and that the natural variability is not specified further. So, what’s your point other than the usual?

  53. To me the question on the 500 # Gorilla in the room is :

    Not

    Show me that CO2 didn’t do it.

    But rather

    Show me that it DID.

    That question goes unanswered in this series of exchanges.

    And answering that question, as in my view the whole basis of modern civilized life – fossil fuel energy – could hang on it, is a fairly important one.

    I’m not convinced to tear up my lifestyle or anyone elses on the basis of show me that it didn’t.

    Show me that it DID.

  54. I have spliced together some of the old daily records from the NSIDC going back to 1972.

    The record arctic sea ice extent (going back to 1972) is March 1, 1979.

    But the real decline in the numbers starts exactly on the peak of the temperature effect from the 1997-98 El Nino – Feb 24, 1998 – which is also the global peak temperature month. After that date, it is mainly downhill.

    I know William Chapman says it started in 1995 but the older (not adjusted by the NSIDC yet) data seems to start the decline in Feb 1998. In fact, the Feb 24, 1998 sea ice maximum is very close to the record on March 1, 1979.

    That makes a lot more sense to me than any of the other explanations I have seen. Global temperature anomalies which are driven by the ENSO (a little more than the GHG impact) are driving the arctic sea ice extent.

    Some other models I have built shows that monthly global temperature tracks the ENSO (lagged by 3 months) better than anything else I have seen (with a little 0.08C per decade global warming impact thrown in.)

  55. Leif Svalgaard (18:10:35) :

    Glenn (16:36:49) :
    Yet the sun and cosmic rays aren’t themselves causes, they are objects, and Meier didn’t say “unspecified” natural variability had been investigated.

    “It is plain that ‘the sun’ etc was meant as a shorthand for a cause or explanation, and that the natural variability is not specified further. So, what’s your point other than the usual?”

    What’s yours? “The sun” isn’t “specified” anymore than “natural variability”, regardless of your claim of it being “plain”. You could have chosen to assume that it was plain that natural variability was meant as a shorthand for a cause or explanation. Out of all that Meier said, this is your best criticism, as usual?

  56. One torch 1 thousand candle power versus 1 candle. Equivalent to a big cycle (50,000 spots) versus a Dalton minimum (50spots) roughly. Why does anybody need to go any further when looking at climate change. All we are talking about is 2 degrees C difference. Take a look at a picture of a maximum versus a minimum. The implications of the lies around this are dramatic when pensioners have to choose whether to heat or eat and the food prices are so high and now the carbon tax. It shows our leaders to be what they are despicable liars with no care for you. We need to make the obvious clear to everybody and not get lost in all this smoke screening.

  57. AMSR sea ice extent
    7,242,344 km2 (October 15, 2008)
    Cryosphere today
    4.8 million km2?????

    Can someone please explain…. They are BOTH sea ice extent (assuming that AREA = EXTENT. Maybe Antony could do an “iceaudit” on both sites LOL…

  58. “The over whelming majority of Americans are just not that stupid and most will be able to connect this foolishness into wondering how much more their electric bill will increase.”

    I’m sorry…I’m American, and I beg to differ. We’ve become a “30-second sound bite” society. No one I know of invests any time in trying to understand this issue, and they’re quite amazed that anyone still believes that climate is not being impacted by humans. They are completely, %100 convinced.
    And when it gets colder?…and colder?…and a “trend” is established?…we’ll be told that it’s “our” fault, and we’ll be told how much worse it WOULD have been had the Gories not managed to grab control of the environment and save us all…and most people will sigh and nod.
    And the other scenario is that people start to wake up?…and do what? Remember the bail out package, and that the public was roughly 100-1 against that package. It was passed anyway, and the version that passed was even MORE insulting than the original.

    So I’m having a very difficult time believing that Americans will suddenly wake up and throw the bums out.

    I’m buying a windmill…not because it’s better for the environment… I’m buying one because I’ll NEED it to power my pc and television during those government mandated shutdowns.

    Jim

  59. Thank you Dr. Meier for taking the time to answer some questions. Apparently Dr. Meier, Obama and McCain did not expect the Arctic to refreeze as fast as it has and the temperatures to be declining as they have. So far no answers from the political side only dictates to be followed. Science? I suspect Dr. Meier knows more or needs to be engaged in a less public forum.

  60. Thank you Dr. Meier for taking the time to answer questions. I wish that some of the answers had both a broader time view, while considering the most current circumstances.

  61. Well it was interesting to read the article by Dr. Meier and then the comments that followed. Although there was such a selective use of information from both sides that all the filtering and analysis left me with a headache.

    “The is the preponderance of evidence presented in thousands of articles that provides the foundation for the human-induced global warming theory.”

    As this is a sceptical site, it would be more credible if he perhaps selected or quoted 25 of the significant journal articles in the literature that supports AGW theory. This would be more convincing for sceptically minded people than vague arguments from authority. Is it unreasonable that a theory have at least a number of ‘key’ articles as its intellectual basis, otherwise surely we are dealing with a hypothesis and not a theory?

  62. Thanks Dr Meier for the answers:
    ….”There is archaeological evidence”….
    ….”Spencer’s work is quite new, and has therefore not yet been properly vetted through the peer-review process”.
    Maybe:… Perhaps …(????) … Dr. Michael Mann

  63. I seem to see Dr Meier’s elephant in the room however it seems to be demolished by my elephant in the room the cause of the M.W.P. (as others have pointed out).

  64. Glenn (18:17:51) :
    Out of all that Meier said, this is your best criticism
    I’ll patiently try again: Fundamental to Meier’s view is that non-man-made causes have been investigated and evidence was found lacking, ergo AGW. While you can look for evidence of a specific cause, e.g. the sun, or cosmic rays, and find that lacking [and I'll not disagree with Meier on those], you cannot credibly claim that evidence is lacking of natural variability from natural causes without specifying which ones among the infinitude of causes. This should be easy enough to grasp.

  65. It is very hard to reconcile the comments made and articles like this (http://www.smh.com.au/news/environment/global-warming/arctic-on-thin-ice/2008/10/17/1223750286963.html) with the temperature and greenhouse gas data that other sites publish. Methane levels in the Arctic appear to be dropping, if the monitoring site data is correct. Alaska has had a miserable summer. Do we believe the data or the analysis?
    If Dr Meier is right with his comments,
    “But as I pointed out above, such “debate” is almost beside the point: it ignores the elephant in the room that is the GHG emissions produced by humans. We may not clearly know what caused the MWP, but we have a clear cause for the current warming: human-caused GHGs.”, what did cause the MWP and how have the models taken this into account.

  66. Presumably we have less data on climatic conditions during the M.W.P than we do now, so that only ‘demolishes’ the AGW theory if one believes that AGW theory claims that it is the sole driver of climatic changes, which it does not. Sceptics also need to be sceptical of the conclusions they sometimes leap to.

  67. Thanks Dr Meier – I appreciate the time and effort you spent for this.

    I have 1 question and 1 comment.

    Question: You’re right in point 2 of answer to question 2 that CO2 levels are rising in the atmosphere as measured at Mauna Loa [and I assume the other observatories, but I have not looked at their data] – but when I look at the CO2 charts, I do not see a correlation between human activity and CO2 level; there’s seasonal variation, but not a human activity correlation. The economic falloff in 2001 doesn’t appear – it, in fact, appears to be a linear annual increase. If CO2 level increase was anthropogenic, wouldn’t there be a correlation?

    Comment: (I can only comment to #7, s the other areas are outside my experience…)
    You’ve drawn a trendline from 1979-2007, and then drawn a trendline from 1979-2008, and used the fact that the second trendline has a sharper slope as proof of increasing global warming – proof of the trend. I disagree with this as proof. Hypothetically, Sept 2009 could show a 9% increase over Sept 2008, and Sept 2010 could show a 9% increase over Sept 2009, and a similar graph, comparing 1979-2009 vs 1979-2010 would, with a smaller magnitude, show the same effect. The melt of 2007 appears to have caused some major issues, but only time will tell as to what those issues will be. By using the change from 2007 to 2008 as proof, you’ve fallen into, at least, the same trap we skeptics have fallen into.

    1979 – 1996 were good years for ice – I agree. 2007 was an extremely bad year for melt – absolutely – but, it does not correlate with global temps, nor does it correlate with global atmospheric CO2 levels. Statistically, correlation does not necessarily equal causation – however – a lack of correlation is typically a good indicator of lack of causation.

    (It’s exceedingly rare to be treated with respect from those who push AGW – I’d like to extend a ‘Thank-you’ to you for the respect you have in your responses.)

  68. CarlC states:
    ‘Do AGW-believing scientists really think that the tiny error bars for “long-lived greenhouse gasses” on the IPCC radiative forcing chart above are defensible? Given that the effect is more from feedbacks than from the direct impact of the gasses themselves, and that there is a laundry list of feedbacks both positive and negative, I do not find them credible. Reasonable, educated, intelligent people can debate AGW. I can’t imagine a reasonable, educated, intelligent person who would vouch for that chart.’

    The radiative forcing chart is for the amount of heating provided by each factor before feedbacks are applied. To know the Co2 radiative forcing accurately we need to have an accurate measure of how much Co2 is in the air, where it is in the air, and how much radiation it blocks.

  69. What is with this?? I just got it off Yahoo news.

    Report says Arctic temperatures at record highs

    By RANDOLPH E. SCHMID, AP Science Writer Randolph E. Schmid, Ap Science Writer – Thu Oct 16, 3:24 pm ET

    WASHINGTON – Autumn temperatures in the Arctic are at record levels, the Arctic Ocean is getting warmer and less salty as sea ice melts, and reindeer herds appear to be declining, researchers reported Thursday.

    “Obviously, the planet is interconnected, so what happens in the Arctic does matter” to the rest of the world, Jackie Richter-Menge of the Cold Regions Research and Engineering Laboratory in Hanover, N.H., said in releasing the third annual Arctic Report Card.

    The report, compiled by 46 scientists from 10 countries, looks at a variety of conditions in the Arctic.

    The region has long been expected to be among the first areas to show impacts from global warming, which the Intergovernmental Panel on Climate Change says is largely a result of human activities adding carbon dioxide and other gases to the atmosphere.

    “Changes in the Arctic show a domino effect from multiple causes more clearly than in other regions,” said James Overland, an oceanographer at the National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Laboratory in Seattle. “It’s a sensitive system and often reflects changes in relatively fast and dramatic ways.”

    For example, autumn air temperatures in the Arctic are at a record 9 degrees Fahrenheit (5 Celsius) above normal.

    The report noted that 2007 was the warmest year on record the Arctic, leading to a record loss of sea ice. This year’s sea ice melt was second only to 2007.

    Rising temperatures help melt the ice, which in turn allows more solar heating of the ocean. That warming of the air and ocean affects land and marine life, and reduces the amount of winter sea ice that lasts into the following summer.

    The study also noted a warming trend on Arctic land and increase in greenness as shrubs move north into areas that were formerly permafrost.

    While the warming continues, the rate in this century is less than in the 1990s due to natural variability, the researchers said.

    In addition to global warming there are natural cycles of warming and cooling, and a warm cycle in the 1990s added to the temperature rise. Now with a cooler cycles in some areas the rise in temperatures has slowed, but Overland said he expects that it will speed up again when the next natural warming cycle comes around.

    Asked if an increase in radiation from the sun was having an effect on the Earth’s climate, Jason Box of the Byrd Polar Research Center in Columbus, Ohio, said while it’s important, increased solar output only accounts for about 10 percent of global warming.

    “You can’t use solar to say that greenhouse gases are not a major factor,” Overland added.

    Other findings from the report include:

    • The Arctic Ocean continued to warm and freshen due to ice melt. This was accompanied by an “unprecedented” rate of sea level rise of nearly 0.1 inch per year.

    • Warming has continued around Greenland in 2007 resulting in a record amount of ice melt. The Greenland ice sheet lost 24 cubic miles of ice, making it the largest single contributor to global sea level rise.

    • Reindeer herds that had been increasing since the 1970s are now showing signs of leveling off or beginning to decline.

    • Goose populations are increasing as they expand their range within the Arctic.

    • Data on marine mammals is limited but they seem to have mixed trends. They are adapted to life in a region that is at least seasonally ice-covered. There is concern about the small numbers of polar bears in some regions, the status of many walrus groups is unknown, some whales are increasing and others declining.

    “This is a very complicated system and we are still working diligently to sort out its mysteries,” said Richter-Menge.

    In addition to Richter-Menge, Overland and Box, lead authors of the report included Michael Simpkin of NOAA, Silver Spring, Md. and Vladimir E. Romanovsky of the Geophysical Institute, Fairbanks, Alaska.

  70. As a couple of posters have pointed out, the following report has appeared today

    http://www.smh.com.au/news/environment/global-warming/arctic-on-thin-ice/2008/10/17/1223750286963.html

    It claims to be a ‘.. third annual Arctic Report Card … compiled by 46 scientists from 10 countries..’. It contains claims such as ‘.. autumn air temperatures in the Arctic are at a record 5 degrees Celsius above normal.’ and ‘.. last year was the warmest year on record in the Arctic, leading to a record loss of sea ice.’ Can anyone point to the evidence for these temperature claims?

  71. The Arctic Report Card is on the NOAA site:

    http://www.arctic.noaa.gov/reportcard/atmosphere.html

    Some quick observations: it leads with the statement ‘Autumn temperatures are at a record 5º C above normal’. But it quickly becomes clear that they are referring to 2007 – a novel and expansive use of the present tense which has tricked many journalists world-wide (not a difficult thing to do though).
    ‘The year 2007 was the warmest on record for the Arctic’ is illustrated in Figure A1, and there is a link to the underlying CRU dataset for surface stations 60-90N. The first statement on the CRU page is ‘From the beginning of January 2006, we have replaced the various grid-box temperature anomaly (from the base period 1961-90) datasets with new versions, HadCRUT3 and CRUTEM3..’. The ‘unprecedented +5° C during October and November across the central Arctic ‘ claim is supported by Figure A2, but the supporting link to the data does not work. I have no expertise in all this and would greatly appreciate hearing from those who do.

  72. Can someone explain to this no-nothing layman why the error bars on the net anthropogenic component are not equal to the sum of all the individual anthropogenic components? Presumably it’s a confidence thing, the chance of all the negative factors being at their maximum and the positive factors being at their minimum is small enough to be disregarded?

    I also surprised that the negative error bar on the net anthropogenic component is smaller than the negative error bar on the cloud albedo effect of aerosols.

  73. I look at that data and I see two different trends. One trend from 1979 to about 1997 or 1998 that is sloping slightly lower and then the trend turns down at more of an angle. 2007 is actually an outlier because of the wind pattern that blew so much ice out of the Arctic that year.

    But this fits with what we already knew anyway. Temperatures too a step up in 1976, before the satellite ice data were available. This step up in temperatures corresponds nicely with a change in the PDO and NAO to more “warm” that “cool”. The PDO basically “switched” phase in 1976. Then around 1998 we had the mother of all El Nino events and this corresponds well to the change in trend to an even steeper angle down.

    But 2007 saw a significant change in the PDO and NAO. Both went to “cool” phase but we had wind currents in 2007 that blew much ice out into the Atlantic and we lost a good deal of the “old ice”.

    Temperatures continued to cool in 2008, the PDO remains in its deepest cool phase since the 1970′s. 2008 began a recovery of the ice. My prediction is that the drastic trend from 1998 is now reversed though it will take another season for the Arctic ice to fully recover with a more normal inventory of ice of various ages. That matters because ice of different age responds differently during the summer melt. Older ice is more durable.

    In any case, my prediction range for ice extent in September of 2009 is that I am fairly certain we will have more than we had in 2008, and I believe it is probable we will have more than 2006 had. I believe the downward trend since 1976 is now reversed and we will see a recovery toward “normal” over the next few years.

    We do not have satellite extent data for an entire cycle of the PDO through a full warm/cool phase. We only have data for a warm phase and the result is, in my opinion, what one would expect with the exception of the 2007 anomaly due to unusual wind patterns.

  74. CO2 induced AGW is based on the IR signature of CO2 . The IR
    signature of natural and man caused CO2 is the same –so how can nature possibly distinguish between natural or fossil
    fuel induced CO2 ? In some ice score samples the CO2 has been as much as 20 times as our present CO2 levels and we have been in an Ice Age.

    Bobprud

  75. Does anyone else find it coincidental that as soon as we as a society developed the computing power to model climates (however inaccurately) that they, the climate modelers, discovered a major crisis that requires them to receive massive funding to further develop computer scenarios confirming their findings? Imagine then if the checks and balances on their results where being carried out by another mob who were also playing with new satelites and found a major crisis that required massive funding for more satelites to confirm their findings etc etc…and so it goes on and on.

  76. Pingback: STAY WARM, WORLD… Roger Carr « Stay Warm, World…

  77. The obvious elephant in the room is bikinis. Bikinis were invented in the 1940s and as they’ve become more popular, global temperatures have increased. There is clearly a strong link so bikinis should be banned immediately.

  78. Don Shaw:

    Your article introuduces telling about autumn 2008.
    But when you read it you find out that they have studied 2007:

    “The report noted that 2007 was the warmest year on record the Arctic, leading to a record loss of sea ice. This year’s sea ice melt was second only to 2007.”

    We all know that 2007 was much warmer in the arctic than 2008:
    FACTS:

  79. Vincent Guerrini Jr

    Cryosphere multiplies area with concentration. Therefore they het a lower number.

    BUT

    Even though this spring and summer there where periods where even when counting pixel for pixel and using concentration too, it was very hard to make things look correct on Cryosphere.
    It seemed that the difference 2008 minus 2007 ice extend was bigger still than the numbers from Cryosphere reflected.
    At one point the subject was taken up here at Antony Watts site, and we all got an explantation, i believe cryosphere said there was something wrong with the 2007 numbers or pictures… !?

    so.. when everyone was looking at the ice extend in the summer 2007 something was wrong? I never found out where that ended, if it ended.

  80. Will Nitschke (19:54:01) :

    you write:
    “Presumably we have less data on climatic conditions during the M.W.P than..”
    Check out this super site where they have systematically garthered temperature studies of Medieval Warm Period, and they got these results:

    Here their site:
    kilde: http://www.co2science.org/data/mwp/mwpp.php

    They deserve attention.

  81. Leif Svalgaard (19:33:29) :

    Glenn (18:17:51) :
    Out of all that Meier said, this is your best criticism

    “I’ll patiently try again: Fundamental to Meier’s view is that non-man-made causes have been investigated and evidence was found lacking, ergo AGW.”

    Patently false and deceptive. Meier’s view is AGW, and fundamental to that is clearly what he claims is evidence for AGW, what he calls the “elephant in the room”. I find it almost impossible to consider that you interpreted his view as being “so it isn’t an unspecified thing called natural variability so it has to be CO2″. It does no service to anyone to intentionally misrepresent another’s view and argument.

    “While you can look for evidence of a specific cause, e.g. the sun, or cosmic rays, and find that lacking [and I'll not disagree with Meier on those], you cannot credibly claim that evidence is lacking of natural variability from natural causes without specifying which ones among the infinitude of causes. This should be easy enough to grasp.”

    Of course, and I’ll try again to explain to you that “the sun” and “cosmic rays” by themselves are not “causes”. And Meier did not claim that natural variability was not specified when considered. That should should have been very easy for you to grasp the first time.

    Perhaps you are ignorant of the fact that claims of “the sun” and “cosmic rays” being responsible for warming are sometimes dependent on eachother, and that there may be an “infinitude” of causes attributable to the “sun” and “cosmic rays”, just as there is with “natural variability”. Your reasoning and complaint requires (besides the innuendo that natural variability was not specified when actually considered) “the sun” and “cosmic rays” only one causal relationship with warming, and that is simply not true.
    Three strikes and you’re out.

  82. Dr Meier has been gracious enough to debate this subject with us, in much the same way that Thomas Aquinas of the Roman Catholic church debated this. http://en.wikipedia.org/wiki/How_many_angels_can_stand_on_the_head_of_a_pin%3F

    He is a believer in his faith and therefore is motivated to match our arguments, by quoting from the sacred writings of the IPCC. The parallels are obvious.

    http://en.wikipedia.org/wiki/Christian_apologetics

    As Dr Meier appears to be a nice person, I for one, hope that he does not suffer lasting psychological damage, when the foundations of his faith are sliced away during the realities of the coming months.

    Overwhelming numbers of voters selected “It’s a cyclical natural pattern that has happened before, and may rebound 85% (768 votes), but 14% voted for “It is a combination of the above effects”. C’mon people. That’s worse than being ignorant like these clowns. “It is linear, due to man made changes, and may get worse 1% (13 votes)”

    I am 65 and have yet to meet a watermelon I could not best, both mentally and physically, nor it it going to happen should I live to be 100. Never sit on a fence as one of those fence posts is going to find its way somewhere nobody should want it entering. 15% of the voters here are dunces or dithers. You should be ashamed of yourselves.

  83. I would like again to point out that anybody who uses the IPCC error bars as if they are real error bars, is strongly deluded, and this detracts from any conclusions based on these plots.

    I will repeat again the quote from the chapter of the ar4 IPCC report that tells clearly that the error bars are artist/modelers beliefs/feelings.

    The AR4 waffles on the errors:
    Let me repeat the direct quote from the AR literature, from chapter 8 that is supposed to evaluate the models:

    ” 8.1.2.2 Metrics of Model Reliability from the AR:
    “The above studies show promise
    that quantitative metrics for the likelihood of model projections
    may be developed, but because the development of robust
    metrics is still at an early stage, the model evaluations presented
    in this chapter are based primarily on experience and physical
    reasoning, as has been the norm in the past.””

    It seems that “experience” and “physical reasoning” have “been the norm in the past” for what passes for science of climate, and since I found this quote, I look at the errors they give with this in mind.

    Dr. Walt Meier has been patient in giving us his point of view, but it really is part of the chorus of AGW. It is a given that CO2 is the culprit in his explanation, and since it is, everything else follows.

    Me thinks that he trusts too much the chorus.

  84. Genuine thanks to Dr. Meier for posting, especially as he was surely aware that there would be a barrage of criticism. I’m one of the “cast of thousands” that almost always just watches the posting, really appreciating the hard work put in by many others, especially Mr. Watts. And I certainly appreciate it when someone from “another point of view” stands up and is counted.

    Re-reading Dr. Meier’s post, it seems as though the point of difference between thoughtful AGW believers and thoughtful “skeptics” is on exactly the same point – quoting from Dr. Meier:

    “From this perspective, it might seem reasonable to assume that because previous change was natural, the current change must be too. Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.”

    To me this summarizes the essence of the debate, rehearsed many times before. One side interprets “simply lacking” as meaning that CO2 is the obvious explanation. And the theoretical grounds are strong. Add CO2 to the atmosphere and the basic physics (and classroom experiments) tells you there is an increase in warming.

    The other side interprets “simply lacking” in a totally different way. It reinforces the view that climate is too complex to model. “Evidence is simply lacking” sounds like – and I don’t want to appear disrespectful to all the hard-working scientist who know way more than I ever will – “we understand it all and because we don’t have *another* explanation for this, CO2 is the only thing left”.

    From my skeptic side, and rightly or wrongly I’ve become skeptical over the last 2 years by reading the blogs & sources on both sides (e.g. realclimate, climate audit, IPCC TAR).. from my skeptic side, exhibit A, there isn’t a climate model that explains the MWP, LIA, or why we came out of the ice age 18,000 years ago.

    Exhibit B – ENSO and PDO. Lots of theories, but no one can predict with the climate models when they will occur or for how long.

    So this is the essence of the disconnect – a skeptic says “of course you can’t come up with a good theory for the warming of the last 50 years, you can’t come up with a good theory for why the ice age finished, the MWP turned into the LIA, or even why the 1998 El Nino was like it was, or when the next big El Nino will occur, so why on earth do you think that you will be able to come up with a theory of the last 50 or 100 years.”

    I think if the AGW people want to convert a significant proportion of the lurkers, doubters and skeptics, they need to present a better case. It’s the point of difference, and Dr. Meier you just glossed over it as if saying it would make it true.

    Present a case that summarizes these 1000′s of peer reviewed papers into something that addresses the above points and 1000s if not 10,000s will move back into the AGW camp.

  85. Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.

    I am not a scientist, but I spend a lot of time trying to come to terms with all the counter claims of scientists regarding AGW. At present, while trying to remain agnostic, I find the arguments against, very considerably more rational and less suspicious than those for.

    The above is a case in point. Dr.Meier, quite clearly an intellectual academic is none the less I would suggest, rather prone to a relay of bald, flat denials of at least a number of arguments which counter his own considered position.

    The para quoted at the top of my non-scientific post is a case in point. I have personally read a deal of evidence which supports the three arguments he puts in quote marks. Two of them are inter-linked anyway – the sun and cosmic rays – which makes me suspect that his intention here was to use the rhetorical “rule of three” to give his point more power, when in fact it is really on a rule of two.

    Further, it looks suspiciously like ‘spin’ to put those three points in the way he did – there is a derogatory feeling to it when one says – suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc.

    This is disappointing. On the one hand Dr Meier presents himself as reasonable, rational, and academic. This posture is undermined by the flat denials of ‘proofs’ as he calls them. They are surely data? And they exist.

    The good Dr. also refers to 30-year periods as lengthy and likely to provide meaningful trend lines. In a system as large, old, and constantly changing as the Earth, that seems to this non scientist as a pretty unlikely statement.

    So while the door is not necessarily closed on this discussion, I continue to think that using his and others’ hypotheses as the basis for the monumental socio-political policies currently being meted out on us, is unacceptable.

  86. Thank you Dr Meier for your answers.

    I read your answers twice and was struck by the following:

    1 Your answers could sound convincing to a layman, but you have an audience containing many scientists. Your answers are, however short of convincing evidence and are aimed at proving your theory, rather than looking at the evidence and all the possible explanations.

    2 You state that there is a lack of evidence for natural causes and thus the elephant in the room has to be human-caused greenhouse gas emissions. This is not logical and is not a scientific argument. If the natural causes are not understood, then the first thing that should be done is to seek out the natural causes of the Medieval Warm Period, the Roman Warm Period, other warm periods in the Holocene and the much warmer periods in previous interglacials. Only when it is proven beyond doubt that the natural causes of previous warm periods cannot be the cause of the current warm period should human causes be examined. It is not good enough to try to sweep the warm periods under the carpet as Mann et al have tried to do. There have to be one or more natural causes for previous warm periods, any or all of which could account for the current and unexceptional warm period, and these have to be explained and discounted before human-caused greenhouse gas emissions can be accepted as the only explanation. The elephant in the room is unknown, but for certain, one elephant is a natural cause, and human-caused greenhouse gas emissions may turn out to be just a flea on the elephant’s back.

    There are many other things in your answers that I would like to touch on, but I think the above two will suffice.

  87. Nick Yates (00:35:12) :
    “The obvious elephant in the room is bikinis. Bikinis were invented in the 1940s and as they’ve become more popular, global temperatures have increased. There is clearly a strong link so bikinis should be banned immediately.”

    No Sir! Bikinis should be Removed immediately!

  88. Interstellar chat between the Sun and Earth.

    Earth: Hey, Sun. Look, I just noticed a creature living on me that I can control more than the others. Check this out.

    *Earth alters the ocean currents some*

    Earth: Did you see it. They started to run around faster and seems puzzled.

    Sun: Hehe Yeah. What are those?

    Earth: Humans, been here for just a short time but they are very sensitive to changes.

    Sun: Certainly.

    Earth: I have another trick that makes them go crazy, watch this.

    *Earth blows away som ice from Arctic*

    Earth: Did you see? They went completley wild in a few weeks and started to run around preaching for each others. Ha ha ha!

    Sun: Ha ha ha. They are funny!

    Sun: Let me try some.

    *Sun starts pulsating a bit stronger and faster*

    Sun: Ha ha ha! Did you see that? I could make them run around puzzled also.

    Earth: Stop that! They put up windmills all over me. I can hardly sleep from all the noice now!

    Sun: Hmm, What if…

    *Sun closes his eyes and start pulsating slower and slower and slower…*

    *** To be continued . . . ***

  89. This has been an interesting exchange, I hope Meier stays around.

    Further questions I’d like to see answered:

    . Why isn’t Antarctic Sea Ice retracting?

    . Why is the Southern Hemisphere having (one of) the coldest year(s) since satellite measurements began?

    . Why hasn’t Arctic Sea retracted as fast when temperatures in the Northern Hemisphere peaked in 1998, and is now accelerating when temperatures are declining?

    . On the paleoclimate record: the references given point to CO2 having a warming effect during only the last 4200 years of the total 5000 years of transition to the inter-glacial periods. Why does CO2 stop warming the planet after 4200 years?

    . If:
    a) you don’t know what caused the Mediaeval Warm Period; and
    b) you don’t know if the planet was warmer then;
    how can you conclude that what caused warming back then isn’t causing it now?

  90. Sorry Anthony. I couldn’t even get past the FIRST SENTENCE in Dr. Meier’s response where he completely dismisses the PDO and AMO effect on ice levels. Any 5th grade science student can see a direct correlation with PDO/AMO and the recovering Arctic ice.

    I suppose then that Dr. Meier is not smarter than a 5th grader….

  91. Dear Dr Meier,

    you say, we know the man-made contribution to GHG, studies like http://icoads.cdc.noaa.gov/people/gilbert.p.compo/CompoSardeshmukh2007a.pdf suggest otherwise.
    The “characteristic chemical signature ” is the same for all CO2, you are wrong with your statement under point 3. Another question related to the conclusion in the study, that IPCC models might underestimate natural reasons for the warming of the oceans: Where were more than 95% of all atmospheric CO2-molecules 20 years ago?

    Best regards,
    LoN

  92. To say that arctic sea ice will behave linearly when it is influenced by a chaotic system is preposterous. Using this logic, one would have to conclude that the Dow Jones will eventually reach zero in near future.

    The AMO and PDO do not explain it completely – solar cycles have to be factored in as well. What will Dr. Meier’s reaction be should the caps grow in the coming years? If that happens, will he be ready to throw the AGW theory in the rubbish?

    Again, this morning on German radio, the PIKK scare scenario of sea levels rising 1 meter or more over the next 100 years is circulating.

    Question:
    What is Dr Meier’s estimate for SLR over the next 20 years?
    Surely he can give us a good ballpark figure.

  93. Please allow me to help Dr Meier in his 20 year SLR projection.

    As a taxpayer, I demand to see an answer to this question from Hansen, Mann, Gore, Ramstorf, Meier, and the rest of the tax-payer money leaching authorities.
    Give your estimate, and in few we’ll see if we are really headed that way.

    Watch ‘em dodge, duck and slither away.
    And I’m not interested in a 100 year projection, where none of us will be around to check it.

  94. Gary (14:17:51) :


    Assuming Dr. Meier will do this again, please ask him to address Dr. Stephen Schwartz’s (of BNL) “Heat Capacity…” report, published last December, which essentially says that doubling CO2 from current levels would likely increase global temps 1.5 Deg K.”

    Could you please give more details of where to find this paper? A link would be nice. Thanks

  95. I genuinely don’t get the remark “The AMO does not have a significant influence on the Arctic.” I’ve let Excel do a simple correlation for the 1979-2008 period between monthly AMO values and monthly sea ice extent values, and the value is higher (0,58) than the correlation between monthly sea ice extent and monthly temperatures for the North Pole zone from RSS (0,53) and UAH (0,54).

    Doesn’t that mean that atmospheric temperatures also do not have a significant influence on the Arctic, or am I over-simplifying? Is there a reason why an influx of warmer water into the Artic could not be a contributing factor to current lows?

  96. Glenn (01:14:16) :
    Patently false and deceptive.
    I think you rapidly are becoming an irrelevant minority [befitting your rantings], to wit:

    Phillip Bratby (02:38:33) :
    You state that there is a lack of evidence for natural causes and thus the elephant in the room has to be human-caused greenhouse gas emissions.

    Steve Carson (02:26:56) :
    “However, these have all been investigated and evidence is simply lacking.”
    To me this summarizes the essence of the debate, [...]
    because we don’t have *another* explanation for this, CO2 is the only thing left”.

    captdallas2 (17:52:36) :
    “Evidence can only be lacking for specific causes, like ‘the sun’ or ‘cosmic rays’, but not for unspecified ‘natural variability’.”
    well said

    Roger Carr (00:24:03) :
    Then read much expert comment following this on Watts Up With That? such as: Leif Svalgaard : (Meier) “Many natural explanations for the current observed [...]

    —————

    It is plain that if there HAD been strong evidence for e.g. the sun or cosmic rays being causes of climate change, that Meier’s argument falls flat, so this is the crux of the matter: he can only maintain his stance because there is no such evidence [as he sees it].

  97. Sorry good doctor (Meier), but your comments verge on the disgraceful. I can see you have earned your degree at the IPCC university and read very well from their bible….you all speak the same lingo without backing it with facts.

    Cant believe he quotes Arrhenius (1896) as proof of AGW….they are all reading from the same power point slides.

  98. Don Shaw (16:57:52) :

    Anyone who mistakenly believes the current arctic sea ice extent plots should read the following AP article.

    http://news.aol.com/article/arctic-temperatures-hit-record-highs/214670

    But Don, who are we supposed to believe? The folks who maintain the sea ice extent plots or an
    AP reference with no data to back it up?

    In other words, how do we know the temperatures referred to by your reference are accurate? Perhaps
    we accept the sea ice extent plots as valid and proof the temperature records maintained are incorrect?

    When did you start disbelieving the ice sea plots? And why? Do you know something we don’t know?

    Please tell us if you do.

    I saw many AGW advocates citing these sea ice extent plots when the graphs seemed to support the contention of a diminishing ice cap. No longer. Why?

  99. “It is the preponderance of evidence presented in thousands of articles that provides the foundation for the human-induced global warming theory.”

    As a lawyer I understand the concept of “preponderance of the evidence” in our legal system. I am unfamiliar with the scientific use of the concept. Does it mean that we discount evidence to the contrary of our theory based on the number of articles published? Do we need experiments any more to test a hypothesis? Has the scientific method evolved to mere advocacy? How much “evidence” do we need to falsify a theory?

    I observe that all of the swans that I have seen are white. I advance the theory that all swans are white. Lots of articles are written about white swans. Along comes a skeptic with a picture of a black swan. No. Sorry. All swans are white because the preponderance of the evidence presented in the articles refers to white swans. Is this how science works now?

  100. Thanks to Dr. Meier for his moderate and polite response to questions. I may not agree with the logic but I appreciate the moderate tone of the replies.
    Unfortunately I find that general tenor of the AGW believers is stident, often decending to personal slights to any who have views different from their own.

    Thanks too to Anthony for producing this site This site may yet have a greater impact on the understanding of Climate that all Gore’s propoganda.

  101. Lazlo :

    Yes. you are correct! Time after time you hear some “news” which is in fact old data, old news, especially in theese cooling days when there have to be som warming news

    MORE EXAMPLES:
    I feb 2008 we heard “news” that ALPE GLACIERS are shrinking “new results” – just after this record winter (!?), but these “news” where in fact from 2005 and back. Misleading indeed.

    We OFTEN still hear that SEA LEVELS are rising. But the truth is, sea levels has not risen one milimeter since 2005 !

    See this example, Nasa :

    http://climate.jpl.nasa.gov/keyIndicators/index.cfm#SeaLevel

    They specifically write that their graph is updated!
    NASA: “Sea Level Last updated 09.16.08″

    But they have NOT updated their graph. They stopped updating 2´nd quarter of 2007. Why are they not updating?

    Heres the data they could have shown:

    - its sooo hard for them to update for the moment…. Just when sea levels flattens out.

    Ok! You could say that this sea level fall could be “random”. But you cannot say that there is not a fine match between temperature decline and sea level decline right now.

  102. Lazlo :

    Yes. you are correct! Time after time you hear some “news” which is in fact old data, old news, especially in theese cooling days when there have to be som warming news

    MORE EXAMPLES:
    I feb 2008 we heard “news” that ALPE GLACIERS are shrinking “new results” – just after this record winter (!?), but these “news” where in fact from 2005 and back. Misleading indeed.

    We OFTEN still hear that SEA LEVELS are rising. But the truth is, sea levels has not risen one milimeter since 2005 !

    See this example, Nasa :

    http://climate.jpl.nasa.gov/keyIndicators/index.cfm#SeaLevel

    They specifically write that their graph is updated!
    NASA: “Sea Level Last updated 09.16.08″

    But they have NOT updated their graph. They stopped updating 2´nd quarter of 2007. Why are they not updating?

    Heres the data they could have shown:

    - its sooo hard for them to update for the moment…. Just when sea levels flattens out.

    Ok! You could say that this sea level fall could be “random”. But you cannot say that there is not a fine match between temperature decline and sea level decline right now.

  103. That “Arctic Scorecard” press-release says among other things:

    • Goose populations are increasing as they expand their range within the Arctic.

    Now compare this with the original:

    http://www.arctic.noaa.gov/reportcard/essay_loonen.html

    Rather different eh? Only about a third of arctic goose populations are increasing, and a quarter are actually declining.

    Actually this is a fair summary, which notes (correctly) that changing agricultural practices and decreased hunting in wintering areas are the main reason goose populations are growing.
    However as usual all these complications gets filtered out in the press-release so as not to confuse the yokels.

  104. It’s just sad sophistry. Why can’t these scientists re-examine basic assumptions in the face of data that does not support their hypotheses? That has been the road to progress in science since the beginning of time. Where will this mistaken road lead these poor deluded ones? Nowhere good, that’s for sure.
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  105. Here are a few links showing current and forecast Arctic autumn temperatures. The rapid freeze this year is of course due to cold temperatures, not warm ones. The AP article is full of spectacularly incorrect information.

    http://www.crrel.usace.army.mil/sid/IMB/newdata.htm

    http://wxmaps.org/pix/temp2.html

    An amusing claim from the article was that reindeer herds were declining, when in fact the study said exactly the opposite – that they were at a long term peak.

  106. I have a problem with the Radiative forcing graph? Only 1 natural forcing for the entire climate? If el nino doesn’t have an affect on the climate, then why is there a spike in 1998? Don’t let facts get in the way of a good story.

  107. WarmWilliam (05:56:43) :
    Thanks to Dr. Meier for his moderate and polite response to questions. I may not agree with the logic but I appreciate the moderate tone of the replies.
    Unfortunately I find that general tenor of the AGW believers is stident, often decending to personal slights to any who have views different from their own.

    William, I take it you’ve read the responses in this thread?

    Some examples:

    Sorry good doctor (Meier), but your comments verge on the disgraceful. I can see you have earned your degree at the IPCC university and read very well from their bible….you all speak the same lingo without backing it with facts.
    Dr, Meir is a good salesman, but there is nothing new in this. It is obvious that he is an unconditional believer in AGW, to the point that all facts must bend to the AGW theory or be considered irrelevant because of the “elephant in the room”.
    I wonder if Meier has ever thought about the possibility that all those thousands
    of peer reviewed studies of AGW were based on flawed data or analysis. He refers to the body of evidence through the thousands of scientists who have found GHG made by man as the prime force for AGW. To me its the Pied Piper effect.

  108. “… this evidence is readily available in thousands of unrelated peer-reviewed scientific journals.”

    In light of how the Mann “Hocky Stick” was fabricated and pushed through “Peer-Review” … the statement above means nothing to me anymore.

    Do all these “unrelated peer-reviewed” studies simply have the obligatory:

    “….Oh, and by the way …. we believe this is all due to Man.” …. pasted to the end?

  109. Sorry Doctor, I am not convinced.

    As we at present in the midst of a global financial crises I would like to draw a comparison.
    If I went to a Bank that did not know me and asked for a loan of $1,000,000 and the only information I could give them was my approx. age, it looks to me that if you were the manager of that bank I would get my loan, PLEASE Dr. change your vocation.
    Hell, there is not one scientific org. that can even estimate the number of active volcano’s under the sea. ( personal experience. ) Sailing a yacht in the lower Pacific we encountered a seawater temp. increase of 12°c. Spending a day in the area we found that the affected area was some 23 miles across sea depth was at an average of 2 miles and the center was visibly higher with gaseous activity.
    Now deep down there was one hell of a lot of bubbling, but upon our return to Auckland in New Zealand and inquiring with a NZ government volcanologist, he said thank you for the information, it was an unknown volcano, BUT!!! there were hundreds of active volcano’s in the southern Pacific.
    CO2,? for billions of years, it was no big deal.

  110. Regarding the 800 year lag time,

    why 800 years if we can already (apparently) see feedbacks kicking in now within decades?

    There is something I’m not understanding.

  111. I wish to add my thanks to Dr. Meier for his answers and for his contributions to this blog’s discussions. I would also like to admonish certain posters to keep the tone respectful.

    With that introduction, I am grateful that Dr. Meier confirms my understanding of the AGW position. Yet, I did not find the answers to be persuasive; nor the references – they were not persuasive two or three years ago, and they are even less persuasive now. To avoid repetition of other posts, I will not dive into many details. I am amused by the elephant comment. I do not know of any mainline climate skeptic that ignores the elephant he mentions, but it seems that “global warming pessimists” seem to ignore the rhinoceros, the hippopotamus, and the Apatosaurus in the room.

    On point #6, one feedback that Dr. Meier omits is precipitation itself. More than one respected analysts have pointed out that if the models permit slightly more precipitation, then the warming effect negated.
    On point #5, I have long been intrigued by this graph. It suggests that the key to climate is radiative forcing with subsequent feedback, and if not for human activities, the radiative forcings would have been essentially flat since 1750. Does that mean that we would still be in the Little Ice Age if the Industrial Revolution had not come along? Somehow the world got into Little Ice Age, but the only significant driver of climate since then has been human induced radiative forcing.

  112. I was delighted to read Dr. Meier’s input. It is very nice to see quiet and rational discussion from the AGW side…even if I disagree…and it was off-putting to see some of the comments here that attack his credentials and him personnaly…thoses comments are uncalled for! Respectfully question his data and conclusions all you want…that is what we are here for..after all, if we can not refute his points, then he just may be RIGHT!

    As a biologist, I would, however, like to make an observation. I believe he has mis-identified the species of said elephant. It is not an AGW elephant, it is an unknown species of variable climate elephant. Just becasue we are having trouble identifying it, you can not justify jumping to the conclusion that it must be the AGW variety…unless and until you can conclusively demonstrate that it is inflated by CO2 enhansed hot air.

    We do not have to be able to prove that we understand climate changes to disprove AGW. We only need to show that AGW does not adaquately explain what we see happening in the real world. The AGW folks have made some very specific predictions reguarding what we can expect by 2012. Either thier predictions will pan out..or their theory goes into the dust bin.

    Expect to hear lots of screaming coming from the dust bin….
    cdl

  113. Dr Meier,

    you say that

    “Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.”

    Pardon, but the evidence for e.g. cosmic grays holds just as well as the case for AGW. You should honestly admit that the other possible explanations have not been refuted. Neither have been proven and neither have been refuted.

  114. Alan Chappell (08:46:31) 12 degree centigrade increase in temps from a volcano two miles down, and they try to tell us that the 1999 volcano in the Arctic didn’t effect the ice.
    ====================================

  115. Frank Lansner wrote:

    “We OFTEN still hear that SEA LEVELS are rising. But the truth is, sea levels has not risen one milimeter since 2005 !

    See this example, Nasa :
    http://climate.jpl.nasa.gov/keyIndicators/index.cfm#SeaLevel

    They specifically write that their graph is updated!
    NASA: “Sea Level Last updated 09.16.08″

    But they have NOT updated their graph. They stopped updating 2´nd quarter of 2007. Why are they not updating?”

    Frank, actually there’s a tiny square in the top corner of the graph. If you hover your mouse over it, it says, “Latest measurement, 39mm August 2008″. No idea why they’ve stopped recording on the graph though – it seems a bizarre way to show a measurement.

  116. So CO2 lags by 800 years in the ice cores, and the current theory is:

    1) For Unknown Reason A, the temperature starts to rise.
    2) For Unknown Reason B, 800 years later, CO2 starts to rise.
    3) For Unknown Reason C, that initial 800 year temperature rise stops dead, and CO2 takes over the warming, which produces more CO2 (See Unknown Reason B) which strangely continues warming with the same trend rather than an increased trend (can trends increase?) even with the extra CO2.
    4) For Unknown Reason D, the temperature starts to drop, even while CO2 is high.
    5) For Unknown Reason E, the CO2 finally catches up with the dropping temperature, and begins dropping itself.

    And this is considered the ‘proof’ that CO2 is responsible for Global Warming?

  117. Dr. Meier states that “the elephant in the room that is the GHG emissions produced by humans”. I respectfully disagree. The “greenhouse gas” elephant in the room is water.
    The anthropomorphic CO2 contribution to a trace atmospheric gas is the mouse in the room with the AGW lady up on the chair screaming. I thank Dr. Meier for his efforts but it just reinforces my impression that the AGW faction no real reply to the questions of the so called “skeptics”. There also seems to be an implication that the onus is the skeptics to present an alternate theory in order to discredit AGW. No, one just needs to show the flaws in AGW to discredit it.

  118. Another great thread from Anthony by inviting Dr Meier. Thank you both of you. May we have lots of these! Of course, I disagree with Dr Meier pretty radically – from the very first sentence in fact, saying AMO has no effect on the Arctic, which I see as contradicted quite clearly by the graphic evidence here: http://www.intellicast.com/Community/Content.aspx?a=128

    I would like to see a Climate Audit of the IPCC chart which gives CO2 such a big share of the pie.

    I wonder how much Dr Meier reads of the posts here, how much gets filed under “classic skeptic issues” without too much examination. It is VERY easy to do this IMO.

    I agree with Phil about courtesy levels – although when one disagrees radically about something that seems this important, it can take time to learn to be courteous. More real debate would help with this.

  119. Seems strange to me that seemingly all the warming is taking place in the Northern Hemisphere, while the Southern half of the planet seems to be going in the other direction. Temps in Antarctica are cooler and ice mass is growing. Could it be that since the majority of the population lives in the NH, and most of the industrial pollution orginates in the NH, that warming is indeed man-made, but is not global? Since CO2 is assumed to be homogenous in the atmosphere, wouldn’t this rule it out as a cause? I think we may be barking up the wrong tree.

  120. Jamie and Frank:

    Yes, Jamie, there may be a reason, but bizaare is the appearance of the NASA graph on http://climate.jpl.nasa.gov/keyIndicators/index.cfm#SeaLevel“

    They do cite U of C, and without doubt, here is the graph with the missing data points.

    Strangely, the NASA graph omits all the data points well below the trend line in the last couple of years. Meanwhile some people may object to the comparison of two graphs on the NASA site. The first runs for 100 years based on estimates from 23 tidal gauges, then a few years are skipped, and the next graph picks up with satellite measurements. Many researches would cry “Foul!”

  121. edwardturner (16:03:24) :

    [Meier]:However, since about 1995, the AO has mainly been in a neutral or negative state. Under such conditions, the Arctic sea ice should have started to recover. Instead, sea ice extent has not only continued downward, but the decline rate has accelerated.

    “But the NAO has been extremely positive over this period.”

    Although be careful to notice your ref claims to represent only winter indexes.

    http://www.cpc.noaa.gov/data/teledoc/nao_ts.shtml

  122. I’m confused. I thought Dr Meier was referring to the winter index?

    a substantial amount of the decline in the sea ice during the late 1980s and early 1990s could be attributed to a strong positive mode during winters because the positive mode favors the loss of thicker ice that is less likely to melt during summer. However, since about 1995, the AO has mainly been in a neutral or negative state.* Under such conditions, the Arctic sea ice should have started to recover. Instead, sea ice extent has not only continued downward, but the decline rate has accelerated.

    * Between 1995 – 1999 it was mostly negative. This chart shows the AO has, since 1999, been more positive than negative (except the notable winters of 2001 and 2003 which were very negative).

    In light of evidence of a positive NAO over this period (during the important winter months) this paragraph of Dr. Meier’s doesn’t stack. Conditions were not especially favourable for ice recovery since 1995.

  123. Let me add my thanks to Anthony and Dr Meier for enabling this exchange.

    A few responses …

    David Hagen, (also Frank Lansner) – The most important greenhouse has H2O is commonly assumed to increase with increasing temperature due to CO2. I do not recall having seen quantitative evidence that H2O is increasing.

    Try this – Attribution of observed surface humidity changes to human influence

    from the conclusion The results presented here add to an increasing body of evidence that atmospheric water vapour has exhibited a significant upward trend over recent decades. Although such a moistening has long been predicted as a response to warming induced by greenhouse gases, this study demonstrates that the observed increase in surface specific humidity is directly attributable to anthropogenic influence and is distinct from the predicted response to natural forcing..

    BernardP Should we understand that scientists can ascertain that one carbon dioxide or methane molecule is natural and another is man-made?
    LawofNature The ‘characteristic chemical signature’ is the same for all CO2, you are wrong with your statement under point 3.

    Dr Meier is right. The ratio of carbon isotopes is different in CO2 that is the result of fossil fuel combustion than that from natural sources, so yes we can distinguish between natural and anthrpogenic CO2. This is named the Suess Effect after the Austrian Chemist who first observed it. A similar analyis is possible for methane.

    Gary – Assuming Dr. Meier will do this again, please ask him to address Dr. Stephen Schwartz’s (of BNL) ‘Heat Capacity’ report, published last December, which essentially says that doubling CO2 from current levels would likely increase global temps 1.5 Deg K.

    Annan et al comment on Schwartz here . In this more recent paper Schwartz estimates climate sensitivity as 1.9 +-1K, which overlaps with the IPCC’s estimated range, once uncertainties are considered.

    Ed Scott There more than 31,000 American scientists who disagree with this conclusion. Assuming this is a reference to the Petition Project, there are actually 31,000 scientists, engineers, doctors, dentists and chiropractors who disagree, a tiny, tiny fraction of the total.

    Saying that GHG increase is due to human-caused emissions does not make it true.

    Apart from the isotopic signature, simple carbon accounting does it. In a sentence, we know with sufficient accuracy how much CO2 has been produced by fossil fuel combustion and deforestation, and the actual increase in concentrations is less than this would produce, so we can confidently attribute all the increase to human activity. See Takahashi, Science, Vol 305, Issue 5682, 352-353.

  124. Anybody know what the ‘seasonal signals removed’ on the NASA graph means?
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  125. It’s pretty cute the way we are referred to Real Climate for discussion of Roy Spencer’s latest feedback work. He does admit that feedback to the initial forcing of CO2 is problematic, but really minimizes the amount of uncertainty in that key factor.
    ======================================

  126. Hey Professor, Real Climate is not an honest forum. Hasn’t anyone ever told you that?
    ==================================

  127. “We may not clearly know what caused the MWP, but we have a clear cause for the current warming: human-caused GHGs.”

    What a lack of humility in science! I think AGW theory ticks off staticians and mathematicians the most. Hey, I lost 5 lbs last month; that means in another 40 months I will weigh zero! Alarmist scientists should know you can match many equations to any squiggly line with a ton of factors to fudge, that doesn’t mean your model predicts the future. Be very careful when you extrapolate empirical data. Be very careful when you use proxies to supposedly fill in your empirical data. Never assume that just because your model is as good as you can get it, that is actually any good at all.

    The only cure for this AGW theory ailment is time in the real world. However the worst part is that alarmists are destroying the base ACTUAL environmental problems to be solved. What a collossal waste of time and effort.

  128. John Philip:

    A couple of responses. Isn’t one of the authors of “Attribution of observed surface humidity changes to human influence” also one of Mann’s co-authors; need one say more!!!

    Disputing the 31,000 scientists is comparable to debunking claims made that 2,500 climate experts contribute to the IPCC. Only a handful are climate scientists, and most of these form an incestuous clique.

  129. Furthermore, the summary of Lindzen’s work the professor refers us to just repeats the standard error of increased temperature magnifying the effect of water vapor by increasing the amount of vapor in the atmosphere. Isn’t this precisely where the theory is not being supported by data?
    ================================

  130. I am of a mind with a lot of others. I thank Dr. Meier for his time and in seriously addressing the questions. He did discuss and grant some conclusions that, I feel, others who endorse the human-induced global warming hypothesis would not have done. Nonetheless, similar to Leif’s first (and only?) post, I think Dr. Meier does nothing to advance the debate beyond pointing out what we’re fairly sure are NOT the main causes behind the Arctic melting. But, as the Climate Skeptic says on his website, that doesn’t mean that scientists can automatically assume that their preferred reason must be the cause. It has also been my impression that global warming is top-down not bottom-up, and would begin with a warmer upper atmosphere where GHGs trap solar radiation. Satellite measurements show no positive trends for that for the past 7 years. If GHGs now heat the surface but not the atmosphere, I would like that explained as to why. There is also little information provided, perhaps because of the questions, about natural heat-transfer mechanisms, how they are operating, and what their effects are.

    Either way the majority of Dr. Meier’s case seems to hang on the radiative forcing power of GHGs, which I have read enough about not to buy, insofar as their proposed catastrophic warming effects. I personally believe that mankind has to have some effect, but to what measure we shall see. Dr. Spencer’s work should be most informative on this matter as far as showing exactly how sensitive the climate is to man-made changes. I understand his work has not been peer-reviewed, but there is a lot of bunk out there that has been peer-reviewed, so I do not put a lot of stock in that process. James Mann’s HS was peer-reviewed, unless I am mistaken, and Steve McIntyre destroyed it after it was officially “approved” by peers AND included in the IPCCs reports.

    If there have been some vehement reactions, unfair and uncalled for though they certainly are, it should simply go to illustrate the lack of trust that AGW advocates have among those of us less inclined to accept their explanations. There are very good reasons for this mistrust, not the least of which is the substantial political connections associated with AGW advocacy, though that may not apply to Dr. Meier himself directly. Also, since he cites Richard Lindzen, I should point out to Dr. Meier that Lindzen also wrote a paper asserting that climate science is very much ill-prepared at this point to answer the question of “is global warming being caused by man” either effectively or honestly. If he will read that paper, he will understand, I believe, the foundation of the rejection that is here elicited to the AGW hypothesis as well as the poor view of peer-reviewed research on this issue. That, taken along with so-called evidence such as Mann’s HS that was first trumpeted as proof and later brutally exposed, will go far in explaining the reluctance of many to accept his explanation wholeheartedly.

    Several others have pointed out that the MWP was warmer than now and Dr Meier acknowledges that in his comments; however, the calculations on the catastrophic effects of human-emitted GHGs are calculated via computer models that have a significant positive feedback bias, and they are the ONLY reason why we would assume that increased warming of the planet (whatever the cause) would not be a good thing. They are because integral to their functions is the mathematics that is assumed to be operating the natural forces of Earth’s systems and its reactions to human-emitted GHGs. While these models are improving, they are still seriously flawed and prone to input biases. That the IPCC is an intergovernmental panel by definition also screams political involvement and interference.

    To tie-in to current events, some Wall Street firms used computerized risk-assessment models to “prove” to regulatory bodies that they were in good shape. Yet it is clear to all today that those computer models, supposedly representing reality in their mathematics, failed or were biased so as not to point out significant errors. In regards to climate science, calling their role a “significant supporting” one is rather disingenous. They are supposed to represent the proof of the accuracy of AGW climate mathematics as relates to GHGs and all the interactions their effects are supposed to cause/enhance/inhibit. They may not represent all the research, but much like the IPCC reports they represent a great body of the peer-reviewed and published research which has been programmed into their modeling. And they are not presented as interesting finds in their results but as proof of the probable outcomes of human-induced global warming.

    So, if he gives further explanations, I should encourage Dr. Meier to tackle the issues of: 1) trust, 2) political involvement/interference in scientific research and results, and then address 3) scientific findings. Without those first two his answers are entirely incomplete with respect to anything AGW is supposed to cause. I say this because not only do many disagree with his scientific findings, but they do not trust some of his sources (like RealClimate for instance), and the research involved with AGW is of such a politicized nature (Al Gore, James Hansen, Obama, EPA, IPCC, etc) that this subject absolutely must be satisfactorily addressed prior to results being discussed. It is that simple.

  131. Now he wants to sneer at the last few years being a ‘trend’ while repeating the canard about 1998. If the climate cycles naturally, as it has forever, why can’t he see the last decade as the last warming cycle peaking and now turning downward. He is way too cavalier with the idea that natural cycles don’t still predominate. The elephant in the room is that he doesn’t understand natural cycles, and won’t admit it. And the same goes for all the people pushing the CO2=AGW paradigm. Well, the elephant is about to roll over on them. You’d think they’d at least have the sense to get out of the way.
    ==============================

  132. It is becoming obvious that climate regulation is an extremely complex matter, beyond human understanding, yet. It is the height of arrogance to claim a trace gas is the main climate determinant, the elephant, so to speak, when he hasn’t a clue to what a real elephant looks like. To substitute a simple concept as an explanation when the real one is monstrously complex is not just arrogant, it is scientifically pitiable.
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  133. I, like several others on this site, am not a scientist. That being said, I am also not devoid of a somewhat logical thought process.

    I’d like to take the plane back up from the treetops to the “30,000ft” level, and point out a few of the things that I have not been able to reconcile in the AGW dispute, which ultimately make me sit on the skeptic/denier side of the pews. In order for me to change my mind, I need some clear, logical, concise answers regarding the same points that get discussed over and over and over, but never actually answered, at least not for folks like me.

    1) I’ve read both here and over on CA that Mann and his fellow scientists refuse to release their methodology and data, which would allow other scientists to review/validate their work.
    Why is that? Steve McIntyre seems to have found numerous errors along with failure to follow what would be termed “minimal acceptable practices” in other fields, so why does this road block approach continue? This makes no sense. Release the code, release the data, so that the research can be independently verified. Otherwise, people absolutely SHOULD be skeptical of what is being hidden. If nothing is being hidden, release it all, period.
    Oh…and the “Why should I release it so you can try and poke holes in it?” argument is very simply answered…that’s what science consists of.

    2) Why don’t AGW scientists admit it when there are errors or skewing in the data? Looking at the work that’s been done to “audit” the ground stations used to provide weather data, it’s obvious that there are a great many flaws. Stations have been moved, and no, “adjusting” the data for urbanization doesn’t fix it. All that does is create an argument regarding the proxy/adjustment formula. Stop arguing about the proxy formula being used to adjust data and go MOVE THE DAMNED THING to a site that meets the acceptable criteria for such stations.
    3) Please explain why temperature trends are down, and C02 is up, and up in a very linear fashion. Answers like “We can’t find any other reason, so it must be C02.” are not sufficient for me to change my mind, and frankly, really diminish or eliminate any respect I may have had for you and your point of view.

    There are more, but these would at least get me started.

    Jim

  134. John Phillips- you said “..the actual increase in concentrations is less than this would produce, so we can confidently attribute all the increase to human activity.”
    I don’t follow.
    If there are two sources of CO2, Human + Natural; and observations show change in concentration of CO2 <Human; How does it follow that ALL of the change in concentration of CO2 is Human?
    Could it not be that the absorption of Human + Natural CO2 is in proportion to their relative concentrations?
    It seems to me that the following argument should also be allowed -
    Change in concentration of CO2 is <Natural therefore ALL the change in concentration is due to Natural.

  135. Calling CO2 the main determinant of climate today is a lot like saying the sun revolves around the earth. It looks like it does, but it’s because our understanding is not sufficiently developed to know the real truth. What a hoax this Arrhenius hatched. He thought it was a hummingbird and it’s been exaggerated into a condor.
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  136. John Philip

    Your link “attribu…”
    Yes, the relative humidity remains approx constant as the models predict, and then they find that humidity therefore increase with increasing temperature.

    But how does this match the measured relative humudities:

    http://bp3.blogger.com/_IiWf8u5z6NI/SFwxs7ZKd0I/AAAAAAAABLc/QtvIUbhMeo4/s400/GlobalRelativeHumidity300

    Most interesting is of course the actual amount in the atmosphere
    925 mbar: Here you see rise, but only to what already was present around 1940-50…

    700 mbar: FALL

    500 mbar: FALL

    So overall there is no doubt, that theres is LESS water in the atmosphere today than in the 1940-50 íes.
    And for most of the atmosphere, there is not even a rising tendensy today.

    So again, it IS a problem to suggest POSSITVE FEEDBACK based on increasing water content, when there is not an increasing water content.

    (Especially interesting is is that we today have lower water content than in the 1940´ies – 50´ies: If we link temperature to water content, then it should be colder today than 60 years ago? It seems possible with raobcore tropical balloon graphs, arctic graphs, USA RURAL graphs. It seems possible with many graphs where UHI is 100 % eliminated.)

  137. Look, Walt, when even non-scientists can successfully deride your logic, isn’t it about time to start re-considering?
    =========================================

  138. “6. There are feedback mechanisms that can alter the impact of GHG emissions. These include: clouds, water vapor, ice/snow. Ice and snow are clearly positive feedbacks that will reinforce the GHG warming because as they melt, the average albedo (reflectivity) of the earth decreases and more energy is absorbed. The effect of other feedbacks is less certain-and may even counter the effects of GHG warming–but the evidence indicates that they nevertheless do not come close to offsetting the direct effect of GHG emissions. ”

    Well I have some basic problems with Dr Meier’s #6 and with the IPCC’s fig2 “forcings budget” (I hate that word forcings).
    The official NASA/NOAA earth energy budget shows a total of 390 W/m^2 emitted from the earth corresponding to a +15 deg C black body emission which peaks at 10.1 microns. Allegedly, only 40 W/m^2 of that passes directly through the atmosphric window, the rest being captured by GHGs the most prevalent by far being water vapor. Water vapor by itself is perfectly capable of generating all the positive feedback that Dr Meier would like, without the need for any CO2 or other trigegr. More water vapor, means more evaporation so more water vapor warming. Meier mentions the albedo effect of melting ice as a positive feedback; but realistically as any satellite or moon based picture of earth will show, the approximately 50% global cloud cover is the biggest factor in albedo, and the solar irradiance in the polar ice regions is substantially lower than in the tropical regions where water vapor and clouds exist in abundance. Also in the polar regions, especialy the Antarctic inland, the earth IR radiance can be an order of magnitude less than in the tropical deserts so IR emissions from the poles is not a big contributor to global cooling.

    The IPCC chart mentions water vapor only as a minor stratospheric component which it says is a warming influence; but it makes no mention of real clouds which precipitate rain snow and ice on the planet and block large amounts of ground level solar insolation, as well as reflect solar radiation from the cloud tops as the principal component of the albedo.

    As Wentz et al have shown (SCIENCE July 2007; How Much more Rain will Global warming Bring ?) global precipitation and gloabl evaporation must balance or else we would end up with the oceans overhead; and precipitation means dark clouds that block solar radiation from the ground.

    So precipitable clouds are a strong negative feedback; and therein lies the power of water to regulate the global surace temperature. As a vapor it gives positive feedback to stop us from freezing, without the need of any help from CO2, and as a liquid or solid form in clouds, it gives a strong negative feedback capable of overpowering any CO2 inspired warming.

    Nobody ever observed the surface to warm, when a cloud passes in front of the sun. The sun, being a 0.5 deg divergence source casts a relatively sharp shadow zone on the ground where the solar irradiance is lower. Inside that shadow zone, the cooler surface emits a lower IR radiant emittance; that unlike the solar source is at least Lambertian in angular distribution, or more likely, near isotropic due to surface roughness, and very little of that diffuse IR emission will be intercepted by that cloud, that directly blocks some fraction of the complete solar beam; and that is why it always gets colder in the shadow zone. In the polar regions, where the temperatures are lower, the incidence of water vapor and clouds is much lower than in the tropics, so even at the lower emittance levels, there is not much impediment to the radiative cooling.

    Meier, and IPCC discount the effect of solar variance, since the peak to peak range of the solar constant only varies by about 0.1% with the solar sunspot cycles; but the effect of the sun cycle is more related to charged particle emissions form the sun, and cosmic rays, along with the variation of the solar magnetic fields over the sunspot cycle. The result is that cosmic ray flux on earth varies with the sunspot numbers being least at sunspot maxima, and greatest at sunspot minima. the charged particle showers in the upper atmosphere dure to cosmic rays and solar particles are a significant source of cloud nucleation; the Wilson cloud chamber relies on that mechaism to display charged particle tracks in water droplets.

    So the effect of solar variance is much greater than the 0.1% change in the solar constant over sunspot cycles.

    Another effect of the variable cosmic ray flux on earth as a result of changes in solar activity, is that the rate of production of radiocarbon 14 in the upper atmosphere changes with solar activity, and a drop in carbon 14 in the atmosphere, is exactly the same as the signature of fossil fuel burning, since fossil carbon is presumably so old as to be free of carbon 14. There is the Carbon 13 signature that relates presumably to burning of plant matter and forests.

    So a good part of the signature of fossil carbon is the same as the signature of an active magnetic sun and the consequent reduction in water droplet nucleation (cloud formation) which has led to lower than normal cloud cover (precipitable) during the very active solar cylces that we have had ever since the IGY in 1957/8 when the all time maximum sunspot count maximum was recorded; and sunspot peaks have been historically high ever since, up to the demise of cycle 23 and the non appearance of cycle 24 sunspots. this is a far more plausible scenario for the last 50 years of global warming, and now a cooling trend.

    One writer challenged my assertion that nobody ever experienced a surface warming when a cloud passes in front of the sun. he described a situation (which he said he had experienced in the arctic) where clouds moved in over his location and it got warmer due to radiation from the warmer clouds.

    No argument from me; except that doesn’t meet the conditions. In the Arctic ice regions, the sun never gets high above the horizon, and a cloud that intercepts the direct sunlight is nowhere near overhead, but down low on the horizon, and many miles away from being overhead. The over head clouds that moved in on him were actually a warm air mass fullof moisture that moved in,and they likely didn’t even block the sun at all. The reflectance of snow that is more than a few hours old is grossly overestimated. Compared to snow that is about 14 hours old, 44 hour snow has from 40 to 80 percent rofh reflectance in the 0.9 to 2.5 micron band, and that drops as low as10 percent for 70 hour snow. At longer wavelengths, water is almost totally absorptive of long wave readition, with a corresponding low radiant emittance (Kirchoff’s Law), so the albedo contribution of arctic snow and ice is rather minor.

    Polar orbit satellites have only been with us since 1979 or so, and they first gave us a glimpse of the total arctic ice pack (antarctic too), and you will recall that was a time of very advanced ice which led to threats of an imminent ice age. And it is those early images of an abnormally advanced Arctic ice that AGW fans like to compare with the 2007 extreme ice retreat; not the normal levels of that ice.

    Also global cloud monitoring from polar satellites is equally young; and those measurments are somewhat limited, because they can reveal albedo effects, but are hardly a good measure of ground level insolation due to water laden clouds. Global measuremnts of effective cloud cover from the ground have to be considered to be very primitive, a there isn’t any simple way to continuously monitor the entire globe.

    When such data becomes obtainable, I am quite confident, that we will find that the global balance between clear water vapor laden positive feedback air, and water/ice laden precipitable clouds, is all that is needed to explain the temperature regulation of the earth.

    Anything like cosmic rays or other charged particles, aerosols, volcanic dust and other droplet nucleating sites, lower the equilibrium temperature needed to maintain the proper cloud balance, while very clean air, and low charged particle/cosmic ray flux, that inhibits cloud formation raises the required equilibrium temperature rquired to establish the ocrrect cloud level.

    All that trace GHGs like CO2 et al do, is simply reset the cloud cover percentage to a different value; but that miracle substance Water in all three phases (the only GHG that exists in all phases in the atmosphere) is fully in control.

    So long as we have oceans, we couldn’t change the temperature of this planet, either up or down, if we wanted to. Besides, what mean global temperature would you set it to, if you could.

    George

  139. The results presented here add to an increasing body of evidence that atmospheric water vapour has exhibited a significant upward trend over recent decades. Although such a moistening has long been predicted as a response to warming induced by greenhouse gases, this study demonstrates that the observed increase in surface specific humidity is directly attributable to anthropogenic influence and is distinct from the predicted response to natural forcing..

    A huge assumption. There’s no way to tell if the rise in water vapor is the cause of warming or a result, nor whether its increase is human-caused.

  140. Pingback: Well done, Watts, but… « Old man in a cave

  141. George E. Smith (14:52:55) :
    Global measuremnts of effective cloud cover from the ground have to be considered to be very primitive, a there isn’t any simple way to continuously monitor the entire globe.
    There is a program to monitor the albedo of the Earth by measuring the intensity of ‘Earthshine’ on the Moon. Data goes back more than a solar cycle and are continuing.

  142. Ice and snow are clearly positive feedbacks that will reinforce the GHG warming because as they melt, the average albedo (reflectivity) of the earth decreases and more energy is absorbed.

    Talk about backwards. LACK of ice and snow might be considered a positive feedback, but the existence of ice and snow would be a negative feedback. Then again, Trees would be a positive feedback, since their tendency to be dark in color means they absorb more heat. And, if ice and snow were such large feedbacks towards cooling, we never would have recovered from the first ice age, but we seem to recover regularly. Clearly tells me there is little overall effect from albedo.

  143. Dr Meier says –

    1. “Many natural explanations for the current observed warming have been suggested… However, these have all been investigated and evidence is simply lacking. ” and,

    2. “…it might seem reasonable to assume that because previous change was natural, the current change must be too.”

    I have problems with these propositions as follows:

    1. The fact that at any moment in time evidence for some proposition is lacking can in no way show that the proposition is false. (Of course, that applies equally to lack of evidence for AGW – lack of evidence doesn’t prove it false).

    Informed opinion can make shrewd judgements about what is likely or not, but that remains opinion, albeit well informed opinion (or not ;-) ).

    To falsify the theory that ‘global warming is natural’ one has to show that it is incompatible with some other theory which can be proven.

    Such a theory might falsify directly some part of the original theory; or it might be another theory altogether that provides a sufficient explanation for the observed phenomena.

    It seems to me that there are papers being published now which provide evidence for natural processes which might be candidates for causing or contributing to global warming; and

    There is work being carried out and just beginning to be published which may generate changes in the parameters (read ‘assumptions’) used in the climate model calculations. Some such changes (e.g. in relation to feedbacks) would radically alter the outcomes of the model calculations.

    2. In relation to the second proposition, I think that this is simply a verbal trick which neatly reverses the onus of proof for the argument which is actually being put.

    It is undeniable that the cause(s) of ancient periods of warming were ‘natural’.

    It is also the fact that we know even less about the evidence for the precise cause(s) of the ancient warming than we do about the present warming. But it simply does not follow that there must be some ‘other’ (?) cause. That is just a nonsensical argument.

    So why would one be driven to make such an argument in relation to the present warming? If ‘natural’ causes are sufficient explanation for the ancient warming, why are they not sufficient for the present warming?

    It seems to me that the only thing which would demand a different explanation would be evidence that the present warming was different either as to the quantum or as to the rate of the warming.

    If modern warming is not different to ancient warming, then why would one demand a different explanation for it?

    The onus is on Dr Meier and others to show -
    a) that the modern warming is different from ancient warming; and
    b) that therefore it requires a different explanation.

    In my opinion neither he nor anyone else has shown either of these things.

    And thanks to Dr Meier for giving us his time. I for one appreciate it.

  144. Folks, over at my site, I regularly post (now up to the 3rd) ‘question place’ notes — places for people to ask specific questions about science, particularly if they relate to climate, oceanography, glaciology, and, even more so, sea ice. By specific, I mean something that can be answered at blog post length. A question like ‘what is the evidence for anthropogenic climate change’ is not a blog post length! Some that are, which I’ve taken from above:

    How can CO2 matter if it lags Temperature in the climate record?

    How are the sea ice concentration records spliced (David Smith: I believe you can find some answers to that at the NSIDC site itself, see data set 51; in any case, check papers from Claire Parkinson and Don Cavalieri and company from NASA GSFC — google scholar will get you there)

    Vincent Guerrini Jr. — Area and extent are quite different things. I already have a note on this. See ‘sea ice packs’. In addition, JAXA relies on AMSR and UIUC (Bill Chapman) relies on SSMI. There are additional differences from that.

    Chris Morris — I believe if you check out recent (last few months) news and scientific reports, you’ll find that methane is now being observed to be rising after a plateau.

    Pierre Gosselin — “Surely he can give us a good ballpark figure.” (speaking of Walt Meier, regarding sea level rise). Why? Scientists are often accused of being a bunch of know-it-alls, and here you’re demanding it. Meier’s research (at least what I know him for) does not involve sea level change.

    Leif Svalgaard — In barometers, high pressure makes for a high level in the barometer. In oceans, it works opposite: under high atmospheric pressure, the ocean is lowered (pressed down), and under low atmospheric pressure, it rises. Whether you want a correction for the inverse barometer depends on what, exactly, you’re studying.

    In the near future (whether that translates to days or weeks depends on work life and private life) I should be assembling notes on:
    Why CO2 matters even if it lagged temperature in the paleo-record
    Relative contributions and importance of H2O and CO2 as greenhouse gases
    Why we expected record minima in the Arctic sea ice at the same time as record maxima in the Antarctic sea ice

  145. Leif Svalgaard (15:32:05

    Leif, what did that “earthshine” look like back in 1998, 1999, and 2000?

  146. I think I found it:

    From 1997 to 2000, Earth continued to dim. The researchers suggest, during this time period, the decreases in Earth’s reflectance may be related to an observed accelerated increase in mean global surface temperatures. From 2001 to 2003, Earth brightened to pre-1995 values. The researchers attributed the brightening to changes in cloud properties.

    “At the moment, the cause of these variations is not known, but they imply large shifts in Earth’s radiative budget,” said co-author Steven Koonin, a Caltech physicist. “Continued observations and modelling efforts will be necessary to learn their implications for climate.”

    Item 5

    Click on image to enlarge.
    The research offers evidence Earth’s average albedo varies considerably from year to year, and from decade to decade. “Our most likely contribution to the global warming debate is to emphasize the role of clouds in climate change must be accounted for, illustrating that we still lack the detailed understanding of our present and past climate system to confidently model future changes,” said Enric Palle, a postdoctoral associate at NJIT, lead author of the paper. Pilar Montan~es-Rodriguez, a postdoctoral associate at NJIT, is another co-author.

    http://www.nasa.gov/centers/goddard/news/topstory/2004/0528earthshine.html

  147. George E. Smith (14:52:55) :

    Your comments as written as they are have made all the time I’ve spent on this blog well spent.

    Thank you for a fine line of reasoning and concise summary of water’s role as a GHG.

    Marvelous.

    Thank you.

  148. Dr. Meier is to be commended for his willingness to walk into the lion’s den so to speak, as well as his respectful approach to addressing the skeptics that make up the majority of WUWT readers. Even so, the information he offers is nothing more than the arm waving “there’s a scientific consensus so shut up” babble that we’re all used to by now.

    I read his responses and followed every link he offered:

    Grist: It can… (waving arms in a threatening way)

    CA: It’s got… (putting two fingers in front of the mouth like fangs)

    Look at the bones Dr. Meier!

    Sorry, I’ve got a teenager that can recite Monty Python and the Holy Grail verbatim :-)

    OA

  149. “Jack Simmons (22:30:32) :

    George E. Smith (14:52:55) :

    Your comments as written as they are have made all the time I’ve spent on this blog well spent.

    Thank you for a fine line of reasoning and concise summary of water’s role as a GHG.

    Marvelous.

    Thank you.”

    I would like to second that one. A very well written and explicit explanation. I have a feeling that Mr. George Smith didn’t need a team to help him write it. Thanks Mr. Smith. I believe you may BE the elephant in the room.
    Mike Bryant

  150. Dr Meier, Anthony,

    It is always desirable to rush to get comments in. However, I am sure you will read all comments, so I am adding a comment following further reflection of your answers, Dr Meier.

    We are all scientist so we all undestand that the basis of science is the falsifiability of theory. So, looking at the two theories that we have:

    Theory 1: Within the Holocene and previous interglacials of the current ice age, natural effects have caused the climate to be as warm as, or warmer than, the current climate.

    This theory has not been falsified.

    Theory 2: The current warming is not natural but is human-caused.

    The two theories are mutually exclusive. Since Theory 1 has not been falsified, Theory 2 must be false. You need to falsify Theory 1 in order for Theory 2 not to be false.

    Dr Meier, you have argued this the wrong way round when you state “Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate.” Natural causes of climate change are a fact; one therefore does not need to explain what the causes are (although one would like to know). On the other hand, it is human-caused climate change which is a theory which must be explained and accompanied by evidence (which can be falsified).

  151. Thank you all for the polite discussions. A few additional points:

    1. Long-term is a relative measure. Let us look at the last million years, consisting of 10 glaciations punctuated by regular, (relatively) short-lived interglacials. That pattern has been regular like clockwork, is correlated with orbital eccentricities, and most certainly has not been anthropogenic.

    2. The warm periods have been the periods of the greatest biological production and diversity, whereas the glaciations have produced lifeless icesheets and nearly lifeless tundra over vast areas that are now green. Polar bears, whales, humans, trees, and various other animals and plants are more numerous, productive, and diverse when there is less ice in the Arctic and Boreal regions.

    I don’t have a problem with a decline in Arctic ice. In fact, I’m in favor of it. I don’t care if it is human-induced or not. In fact, I hope it is.

    The “debate,” such as it is, seems to hinge on questions of alleged warming, anthropogenesis, and the assumed travails of global warming. I find the first two interesting from an intellectual point-of-view, but I think the third question (more like an assumption) is kind of dumb-assed. I mean that in the politest way possible.

  152. George – The result is that cosmic ray flux on earth varies with the sunspot numbers being least at sunspot maxima, and greatest at sunspot minima. the charged particle showers in the upper atmosphere dure to cosmic rays and solar particles are a significant source of cloud nucleation; the Wilson cloud chamber relies on that mechaism to display charged particle tracks in water droplets.

    Except that cloud nucleation by cosmic rays has only been observed in the laboratory, and so far in a highly un-Earthlike atmosphere. The CLOUD experiment at CERN is investigating further but has yet to report. Also the correlation evidence that should support the cosmic ray hypothesis in fact contradicts it. For example, Professor Mike Lockwood examined the cosmic ray flux intensity over the period of recent rapid warming and found that the trend was actually the opposite of that required to support the hypothesis -the conclusion:-

    ‘There are many interesting palaeoclimate studies that suggest that solar variability had an influence on pre-industrial climate. There are also some detection–attribution studies using global climate models that suggest there was a detectable influence of solar variability in the first half of the twentieth century and that the solar radiative forcing variations were amplified by some mechanism that is, as yet, unknown. However, these findings are not relevant to any debates about modern climate change. Our results show that the observed rapid rise in global mean temperatures seen after 1985 cannot be ascribed to solar variability, whichever of the mechanisms is invoked and no matter how much the solar variation is amplified.’

    So the cosmic ray influence on clouds is as yet unproven and if it exists is minor compared to other climatic influences. This is why the Royal Society labels it misleading argument No 7.

    The idea that water vapour and clouds alone are the controller of climate bemuses me. Observations show that relative humidity tends to remain constant – at a given temperature, any increase in humidity simply precipitates out in a matter of days. This is why water vapour is a feedback and not a driver of climate – an increase in temperature increases the capacity of the atmosphere to hold water vapour, which gives a higher greenhouse effect and so forth. And indeed specific humidity does correlate well with surface temperature, particularly over the oceans. But we are left with the need for some external forcing to produce the initial warming.

  153. Correction to my post of 00:36:03 of 18th Oct 2008.

    Theory 1 should be:

    “Theory 1: Within the Holocene and previous interglacials of the current ice age, natural effects have caused the climate to be as warm as, or warmer than, the current climate and thus natural effects can explain the current warm climate.”

    Sorry for this error.

    Phillip Bratby

  154. I’m glad at least Anthony has been kind, respectful and gracious with Dr Meier.
    As host, that’s his obligation.
    No one else here has shown much respect for Dr Meier’s position here in this forum. What’s the reason for this?
    It’s quite simple:
    Taxpayers don’t enjoy paying their hard-earned money to an organisation that is bent on fooling the public, and working against what’s in their best interest.

  155. John Philip (13:31:49) :

    Lansner, Frank (14:40:52) :

    I imagine that there can be a distinction between trends in local humidity and overall atmospheric humidity. With changes in land use patterns, we would expect to see increased local humidity – irrigation, lawns & golf courses, water features, and such. In fact, many years ago, John Christy pointed to temperature trends in a major California valley. In the valley where irrigation had been introduced, temperatures had increased (as well as humidity), but higher on the mountains – where GCMs would forecast increased temperatures – the temperatures had actually trended down.
    Increased local surface humidity may indeed be anthropengic and it would not be surprising for such to contirubute to increased temperatures, but the cause of increased local surface humidity is NOT necessarily induced by more CO2. In many cases, we know the culprit is land use changes.

  156. It occurs to me that every AGW proponent with credentials should be begging Anthony to let him/her participate in a post like this one. I believe that Dr. Meier has been treated well here. This type of discussion can only strengthen an AGW proponent. The weaknesses of the theory are exposed in excruciating detail, which can also help to sharpen their arguments. I look forward to posts from a long list of AGW proponents. Who will answer questions from the people? Al Gore, are you next?

  157. An interesting comment from DeWitt Payne on Climate Audit:

    “CT has (finally) updated their seasonal average extents through Summer 2008. Steve Mosher won that brownie bet. I’m now convinced that CT changed their extent algorithm at the end of 2006 in a way that makes the extent loss trend look much worse. Here’s my evidence, the year to year difference in extent for Summer average extent (July, August and September)

    year… JAXA….. CT…. UH (km2)
    2003 178104 157760 146137
    2004 -21795 -137900 27088
    2005 -543877 -383990 -544048
    2006 106515 46030 134330
    2007 -1003957 -2210700 -1072133
    2008 615274 642400 549470

    The difference in the CT extent from 2006 to 2007 is completely out of line with all the other data including the difference from 2007 to 2008, which is again comparable to the JAXA and Uni-Hamburg differences. You can see the same problem in the other CT seasonal averages as well as the annual average. There is a step change in 2007 that does not show up in JAXA or Uni-Hamburg data. For the Summer average, extent went from being about 1 Mm2 larger than JAXA in 2002 to 2006 to 0.22 Mm2 less than JAXA in 2007 and 2008.”

  158. George:
    “So long as we have oceans, we couldn’t change the temperature of this planet, either up or down, if we wanted to. Besides, what mean global temperature would you set it to, if you could.”

    Thank you for this great post. I found it very educational, and very logical.
    I particularly like the summary section, as it presents “the NEXT question”.

    Stated a different way…

    Let’s assume for a moment that everyone agrees that AGW exists. This then means that we CAN exert influence over the temperature, and therefor the environment, of the planet.
    Who gets to choose the temperature?…the faction that says in order to support the global population, we NEED more warmth to increase crop production, etc?…
    What a political hot potato THAT discussion point is.

    This will be MUCH fun :*)

    Thanks again, George.

    Jim

  159. Kum Dollison (21:06:25) :

    Indeed you found a link, but look at the date:

    “May 27, 2004 – (date of web publication)”.

    This seems to be another story like the AIRS CO2, where information was stalled for many years. Note that it speaks of the great importance of clouds and albedo.

    We have to search for a more recent work, and a plot of albedo as derived from the moon proxy.

  160. George E. Smith (14:52:55) :
    discount the effect of solar variance, since the peak to peak range of the solar constant only varies by about 0.1% with the solar sunspot cycles[...] The result is that cosmic ray flux on earth varies with the sunspot numbers being least at sunspot maxima, and greatest at sunspot minima. the charged particle showers in the upper atmosphere dure to cosmic rays and solar particles are a significant source of cloud nucleation[...]

    So the effect of solar variance is much greater than the 0.1% change in the solar constant over sunspot cycles.

    I caution against hitching anti-AGW arguments to the solar/cosmic rays. Should the cosmic ray connection be falsified, the AGW-crowd will take that as a significant boost for their ideas. And so far, the relation does not look good. There has been significant variation of cloud cover [ http://www.leif.org/research/cloud-cover.png ] and albedo [ http://www.leif.org/research/albedo.png ] since 1980, changes that match the temperature changes [as they must - flip the figures over to gauge the match]. However, the cosmic ray flux has not varied like this at all. For example there is no solar cycle signal in the cloud/albedo data.

  161. Re: Lag Between temperature rise and CO2.
    Dr. Meier’s assertion that the lag between changes in temperature and changes in CO2 are irrelevant is a prime example of proving “facts ” by assertion rather than research. Since Jame’s Hanson’s assertion of high sensitivity to CO2 because of positive feedback is based on the 1984 state of knowledge about the Vostoc ice cores that suggested that temperature and CO2 rose together, the assumption of positive feed back and high sensitivity should have been re-examined as soon as the data about the CO2 levels following temperatures became known. Instead the AGW true believers came up with “something”starts the warming and then CO2 drives it. All three examples of proof given by Dr Meier’s are rationalizations that have never been subjected to the cold hard light of scientific research. When the question is asked “Why does CO2 stay high for up to 2000 years after temperatures go down”, the response is a thudding silence. Also the Greenland ice cores and Bond’s ocean cores show that warming is not a smooth 5000 year warm-up but a roller coaster that if anything, is based on a 1500 year cycle. The more I read the AGW literature, the more obvious that it mostly consists of computer models that can only respond to the suppositions that are fed into them, and “thought experiments” (like the 2005 Hanson, Reudy, Sato paper). What ever became of putting the suppositions and rationalizations to the test of scientific experiment? This has actually been done to test the feedback of water vapor (e.g. Douglass and Christy, Hu, Lindzen, Spencer) and in each case, water vapor and clouds were found to show a negative feedback or no feedback. Dr. Meier, why do the rationalizations about CO2 driving the warming trump the real world data that show either a negative feedback or no feedback?
    Suzanne

  162. Phillip Bratby (00:36:03) :
    You are giving AGW a boost by faulty logic:

    Theory 1: Within the Holocene and previous interglacials of the current ice age, natural effects have caused the climate to be as warm as, or warmer than, the current climate.
    This theory has not been falsified.

    Theory 2: The current warming is not natural but is human-caused.

    The two theories are mutually exclusive. Since Theory 1 has not been falsified, Theory 2 must be false. You need to falsify Theory 1 in order for Theory 2 not to be false.

    The two theories are not mutually exclusive. We could [hypothetically] right now have been at a later phase within the Milankovich cycle such that the temperature from that cause was already down quite a bit. It is not logically excluded that there at this point could be a temporary minor warming [that did not attain the much warmer temperatures of long before]. That warming could well be AGW without any logical inconsistency.

    So, if we want to mount a credible attack on AGW, we should not stoop to their level and use faulty logic.

  163. I’m still trying to get my head around:

    “…Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate. This, again, has not been addressed in a reasonable way….”

    As far as I know, no one ever spent a lot of time determining in detail how ‘natural’ CO2 affected climate. I have seen lots of simple Arrhenius-type statements of how it ‘keeps us hot’, but little detail, until the IPCC burst on the scene, with the ’1.6 watts extra’ climate forcing figure.

    Now, I understood that this figure was not proven from first principles, but rather taken from observation, and found to fit when used in computer models. Essentially the models said: the temperature is going up, CO2 is going up, and if the CO2 is the sole cause of the temperature rise, it must have ‘this’ forcing effect.

    What Dr. Meier seems to be saying here is that this forcing is now assumed to be a priori correct, so anyone who suggests that something else is causing the warming must also explain how the CO2 isn’t causing it. I thought that the proposed forcing figure was still a matter for considerable debate – indeed papers are now coming out suggesting that the CO2 forcing contribution is very low. What is wrong with saying that the cause of the 1980-2000 warming trend was an unknown natural cyclic one, and that now we are back in a cooling trend, and that CO2 is of relatively minor importance?

  164. George and Jim B:

    You have pointed out an exciting next question.

    Who gets to set the temperature?

    Apparently ALL AGW alamists want the temp to stay where it was in the 80′s (otherwise they wouldn’t care about warming or cooling). I would suspect that those who live in norhern latitudes and are happy with colder temps would like it set to their liking. I and millions of others who have migrated to the warmer latitudes would like it a little warmer. I am pretty sure tropical islanders don’t want it any colder and perhaps all living animals in the tropics would rather be warm than cold. However, since there really is no “average temperatre” that can be set we must first learn to control local temperatures. Perhaps we could legislate that Florida must remain warm all year and Minnesota must remain cold. Each Country around the world could set their own temperature according to their desires. Perhaps we could force it to rain in the desert and not rain on sporting events. The UN could even erect and patrol barriers between countries that had different temperature settings. What a truly wonderful world this would be.

  165. John Philip (02:49:39) :

    [Attributed to Lockwood]: “Our results show that the observed rapid rise in global mean temperatures seen after 1985 cannot be ascribed to solar variability, whichever of the mechanisms is invoked and no matter how much the solar variation is amplified.’ ”

    “So the cosmic ray influence on clouds is as yet unproven and if it exists is minor compared to other climatic influences. This is why the Royal Society labels it misleading argument No 7.”

    Do you actually read the crap you put out?

    From the Royal Society:

    http://royalsociety.org/page.asp?tip=1&id=6234

    “Even if cosmic rays were shown to have a more substantial impact, the level of solar activity has changed so little over the last few decades the process could not explain the recent rises in temperature that we have seen.”

  166. Glenn (10:29:35) :
    [Attributed to Lockwood]: “Our results show that the observed rapid rise in global mean temperatures seen after 1985 cannot be ascribed to solar variability, whichever of the mechanisms is invoked and no matter how much the solar variation is amplified.’
    Do you actually read the crap you put out?

    First, go and wash your mouth out with soap. Contrast your tone with the polite discourse that has characterized Dr. Meier’s contribution and the discussion so far.

    Second, Lockwood’s analysis is almost certainly correct. Notice that this in no means support for AGW, as there could be so many other [specified :-) ] natural causes: PDO, ocean currents, etc.

  167. Kim,

    What a hoax this Arrhenius hatched. He thought it was a hummingbird and it’s been exaggerated into a condor.

    Don’t be too hard on Arrhenius. As I understand it he thought increased CO2 would be a beneficial thing :-)

  168. Glenn

    Your point escapes me. Please explain which part of my ‘crap’ is giving you a problem?

    JP.

  169. A preprint with the moonshine albedo, from 2004

    http://solar.njit.edu/preprints/palle1266.pdf,

    and also Leif’s link http://www.leif.org/research/albedo.png

    show that the percentage error in the albedo can be fairly high. This, in my books, translates into a systematic error if the assumption in the models is that the albedo is fixed to its average value.

    This means that the models, if they truly calculated their error bands correctly would be so wide as to be meaningless.

  170. JimB (14:24:47) : “I, like several others on this site, am not a scientist. That being said, I am also not devoid of a somewhat logical thought process.”
    You may not think it Jim but you ARE a scientist, you think & question, that is science!
    Well done :-)
    Dave.

  171. Glenn (10:29:35) :

    Oh my giddy aunt. I just read that mess and now know why many of my closest associates claim that the RS is purely political, a spin machine and an arm of the UK government’s propaganda machine.

    It is simply staggering that people claiming credentials can “endorse” the exact opposite of investigation, discovery and enlightenment.

  172. BTW, the poll is flawed — linear is not the same as man made, cyclical is not the same as natural.


    Many natural explanations for the current observed warming have been suggested:”it’s just natural variability,” “it’s the sun,” “it’s cosmic rays,” etc. However, these have all been investigated and evidence is simply lacking.

    Everyone is looking for causes, but what if there isn’t one? We’ve moved away from predestination, but we haven’t moved away from determinism yet. We cannot yet accept that seemingly random change is actually random variation. Chaos even…


    In addition to these possibilities there is also the likelihood that oscillations of climate can occur even if there were absolutely no variations of external forcing of this kind, purely by internal oscillations involving feedbacks among all of the components of the Earth-air-sea system included within the main internal construct. That is, it is possible that the swings in climate are the consequence of a steady forcing of an inherently unstable system that never achieves a true equilibrium.

    (Barry Saltzman, “Dynamical Paleoclimatology”, 2002, p.45)

    This natural explanation has not been proved false.

  173. Thanks to the AGW skeptics we are learning more and more about how the earth’s atmosphere,etc. behave. In my opinion, we don’t learn anything if the scientists just attribute everything to AGW.
    By the way, it must be nice to do science in a climatically controlled environment instead of freezing your tail off actually doing research in the Arctic.Thank you scientists who actually do that work!
    To say after observing only 30 years of data that the only trend possible is linear is nonsense. Why this old rock is several billion years old give or take a several hundred million years. Dang, if I didn’t loose my gardening records in a blizzard,possibly due to the dreaded global warming, I would have longer times series than that.
    I think whoever stated that AGW alarmism bugs the mathematicians and statistician the most is correct.

  174. Mr Tom in sunny & warm Florida said (10:10:36) :
    “Apparently ALL AGW alarmists want the temp to stay where it was in the 80’s (otherwise they wouldn’t care about warming or cooling).”

    I’ve always thought of most of them as being stuck in the 1960s-1970s hippy movement, but that is by-the-by.

    A lot of comments on this thread have, I think, gone too far in their criticisms of Dr Meier’s approach. I do not claim to speak for him, but I do claim to detect an underlying compelling logic to his position. Indeed, I believe it is a line of argument many find utterly persuasive. It is this.

    If we accept that gases in the atmosphere cause the greenhouse effect, it is entirely logical that a decrease in the overall volume of such gases might diminish the greenhouse effect and an increase the overall volume of such gases might enhance the greenhouse effect. Our cars, power stations and flatulent cows pump greenhouse gases into the atmosphere. Without our activities those greenhouse gases would not be created (OK, so maybe the tree I burn on my fire might be struck by lightning and burn anyway, but you know what I mean).

    As a matter of simple logic there is nothing objectionable about the theory that additional greenhouse gases created by human activity are likely to enhance the greenhouse effect and, thereby, cause temperatures to rise somewhere on the surface of the plant by some amount.

    I do not understand Dr Meier’s starting position to be anything other than a recognition of that (entirely rational) proposition. So, when he asserts that it is for those arguing against AGW to prove their case he is saying: “Look chaps, we know we are putting more of the heat-making stuff up there so you tell me why our extra heat-making stuff isn’t making extra heat.”

    To (what I laughably call) my mind, that is an entirely rational, a-political, non-hysterical, commonsensical and logical position for anyone to adopt.

    There might, for all I know, be reasons why the stuff we pump into the atmosphere makes absolutely no difference to anything, but I have always accepted that it probably does make a difference. The question is whether it makes a sufficient difference to justify claims that polar bears are eating each other to stay cold and demands that we must close down our industries.

    This is not the first time comments here have conflated AGW with hysterical AGW Armageddon theories. It seems to me that it is just as difficult to make a case for a total absence of AGW as it is to make the case for imminent melt-down.

    It may be that AGW is so small as to be insignificant, but that is a world away from saying it does not exist at all.

    Methinks some have been keeping their eye on the ball with insufficient assiduity (that is usually my job and I guard it jealously).

  175. Leif Svalgaard (04:17:40) You have written an extension here, Leif, in response to my STAY WARM, WORLD… Roger Carr « Stay Warm, World… (00:24:03) which appears to indicate you did not realise that by clicking on either my name or the title you would have gone to the full story?

    Tom in sunny & warm Florida (10:10:36) writes: “Apparently ALL AGW alamists want the temp to stay where it was in the 80’s…”
    I opt for the climate c.1952, Tom. Perfect!
    Or is that just because I was young and fit then…

  176. FatBigot (19:20:39) Well of course you are right, and I don’t think many skeptics argue that the primary forcing of CO2 is not real. The real question is the magnitude, and possibly even the sign, of the feedbacks which modify that intial forcing. You are correct, though, that most skeptics suspect that the total of CO2 forcings and the feedbacks should not be enough to stampede the herd into wrenching social change.

    Then again, from the ice core data, a rise in CO2 always follows a rise in temperature, followed at a later date by falling temperatures. I’m waiting for the researcher to claim that the rise in CO2 halts the rise in temperature and helps cause the subsequent fall in temperature. Temporally, the correlation is there; we just need a mechanism.
    ===================================

  177. Leif Svalgaard (16:36:51) :

    ” anna v (11:54:01) :
    show that the percentage error in the albedo can be fairly high.
    Perhaps you mean ‘variation’ rather than ‘error’ …”

    True, he variation can be fairly high, but when a model uses a constant average albedo, this variation becomes a systematic error that has to be summed linearly , in computing total error. At least that is standard practice in high energy physics. though we usually give both errors, statistical and systematic.

  178. I know this will be very simplistic, but I don’t understand the whole argument about “first year ice.”

    Last year, a lot of ice melted. I think we all agree on that. But then a strange thing happened… a cold winter froze a lot of ice and ice levels recovered. The argument was that this “first year ice” would melt quicker and that this was a bad thing. Now, they were correct that it melted quicker. There was alarmism regarding the speed of melt early in the summer. But simple physics tells us that more ice takes more energy to melt, and thus will keep water temps cooler for a longer period of time and all that. So, even though 2007 ended up with a deep minimum by historical standards, it spent more time hanging about recent previous levels, stayed above 2008, and the water likely stayed cooler than 2007, which means that as soon as the energy dissipates, a quicker freeze is expected.

    It’s simply unrealistic to expect an immediate leap to ice levels of 20 years ago, just like it’s unrealistic to expect an immediate severe drop in temperatures in the event of a trend to cooling. What we can expect, if indeed the cycle has turned, is a continuing overall increase from the 2007 minimum, where each year we have a little bit more multi-year ice and somewhat thicker “first-year” ice.

    I just find the whole argument regarding the amount of “first-year” ice to be indicative of nothing more than the current state of things rather than any kind of reasonable argument or explanation either for or against future ice levels.

    I fully understand the concern with putting too much credibility into short-term trends. But it’s somewhat maddening to constantly see recent reversals in data completely ignored because there is this unrelenting need to only compare to historical bases, with little to no recognition that if a reversal is afoot, it will take time to completely manifest itself in terms of those historical averages.

  179. Stef (10:44:36) :
    So CO2 lags by 800 years in the ice cores, and the current theory is:

    Nice strawman!

    1) Due to orbital changes and increased insolation, the temperature started to rise.
    2) As the oceans warm up CO2 starts to outgas.
    3) Due to orbital changes, the temperature rise stops, and CO2 continues the warming, which produces more CO2 (See 2) which scontinues warming.
    4) Further orbital changes cause the temperature to drop, even while CO2 is high.
    5) Obeying Henry’s Law the CO2 drops in response to the dropping temperature.

  180. FatBigot (19:20:39) :
    A lot of comments on this thread have, I think, gone too far in their criticisms of Dr Meier’s approach. I do not claim to speak for him, but I do claim to detect an underlying compelling logic to his position. Indeed, I believe it is a line of argument many find utterly persuasive. It is this.

    If we accept that gases in the atmosphere cause the greenhouse effect, it is entirely logical that a decrease in the overall volume of such gases might diminish the greenhouse effect and an increase the overall volume of such gases might enhance the greenhouse effect.

    Dr. Meier’s position assumes that our environment is static and that things like trees don’t respond to the increases in CO2.

    Gilbert

  181. Phil. (23:56:12) :

    “3) Due to orbital changes, the temperature rise stops, and CO2 continues the warming, which produces more CO2 (See 2) which continues warming.”
    4) Further orbital changes cause the temperature to drop, even while CO2 is high.”

    A good use of what the ancients called “deus ex machina”. Not science though.

    There is no proof that CO2 continues the warming. It is a hypothesis that there are further orbital changes. Any links to a study of orbital changes in addition to the ones that started the warming, and CO2? And why after 800 or 2000 years, when the AGW crowd is shouting about 30 years of CO2 tiny anthropogenic excess? 30 years would not show on the plots and CO2 would be concurrent with the rise in temperature.

  182. Fatbigot – a nice summary of the theoretical case for AGW. However one could come away with the impression that the amount of expected warming is vague – we know we have increased GHGs and therefore expect some unquantified warming.

    In fact Dr Meier will be well aware of estimates in the peer-reviewed literature of the size of the forcing effect e.g. (Myhre 1998) and the predicted temperature rise due to that forcing, summarised in IPCC AR4 WG1 Section 9.6 which give an expected increase in temperature, after a doubling of CO2e, in the range 2-4.5C. As this is consistent with recent observations, his point is that the onus is on those who propose a purely natural and alternative explanation to provide a mechanism (solar, ocean circulation changes, or Factor X) that would explain the warming, and explain why the radiative forcing of the increased GHGs is not having the predicted effect.

    We await such an explanation.

  183. Phil. (23:56:12) Speaking of straw, Phil., you don’t know how CO2 interacts with climate so stop pretending as if you do.
    =========================================

  184. Phil. (23:56:12) It’s just as likely if not more so, that orbital changes and insolation are the whole ball of wax, and CO2 only a trailing indicator. Stop making stuff up.
    ===========================================

  185. John Philip (01:35:58) Consistent with recent observations? Please. That is the problem, recent observations are busily disconfirming the idea of high sensitivity of climate to CO2.
    ===========================================

  186. anna v. (01:08:52) Thanks for the Deus ex Machina. I’ve been lying in wait for the chance to tell Phil. to ‘stop making stuff up’.
    =======================================

  187. Kim

    I am using the climatological definition of ‘recent’. The IPCC projected that temperatures would rise at an average of around 0.175C / decade from 1990-2010. According to the UAH satellite record the actual rate was 0.174C /decade.

    regards

    JP.

  188. I really liked the summary Phil. Now all we have to do is cause that “orbital change” thing to bring the temperatures back down! Of course when it gets too cold that orbital thing is ready to go again. Now I understand everything. Thank you.

  189. John (08:07:47) And you still don’t see the problem with your definition?

    lucia’s Blackboard at rankexploits.com for the truthseekers out there.
    ===============================================

  190. kim (07:43:11) I might add I’ve been waiting for months because he doesn’t do it very often.
    ======================================

  191. kim (10:25:08) Furthermore, he might be dead right. He’s just not convincing and isn’t very forthcoming about how speculative it is.
    ==========================================

  192. (John Philip) “The IPCC projected that temperatures would rise at an average of around 0.175C / decade from 1990-2010. According to the UAH satellite record the actual rate was 0.174C /decade.”

    Is that right?! According to UAH, global temperature from Jan 1990 to Jun 1991, i.e. the month Pinatubo erupted, averaged +0.12C. (Average Oceanic Nino Index +0.3)
    Whereas temperature from Jan 2006 to Jun 2007 averaged +0.29C (Average Oceanic Nino Index +0.3)

    http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt

    http://www.cpc.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf [ONI data on pages 25-6]

    That’s 0.106C / decade. (Or would you prefer to skew the 1990-1991 starting point downwards by adding a couple of the ensuing Pinatubo cool years?)

    Of course, this episode of global warming also coincided with an AMO shift to warm phase.

    http://en.wikipedia.org/wiki/Image:Amo_timeseries_1856-present.svg

    The onus is on you to explain why this 0.106C /decade should accelerate dramatically and imminently to a minimum of 0.3C /decade, which even if it happened from 2010 for the rest of the century would only produce a rise of 2.7C by 2100, still well below the mid-point of the IPCC range you quote.

  193. The plot given in answer to Q7, “September Monthly Arctic Sea Ice Extent and Trend” is quite different from the plot I get when I use the data from http://www.ijis.iarc.uaf.edu/seaice/extent/plot.csv — my plot does not look nearly as alarming. It shows the minimums since 2002 have been rather consistent, except for 2007 and 2008. Moreover, it show the maximums slowing declining from 2003 to 2006 and then slowly increasing from 2006 to 2008. If anyone wanted to claim there was a trend for max ice, it would be up, not down.

  194. Anthony, I think the post I just made was eaten by the spam filter. Could you look for it? Perhaps the problem was that I had a URL for the data source of the graph at the top of “Ice Reality Check” but I didn’t make it into an HTML link.

  195. Phil:

    3) Due to orbital changes, the temperature rise stops, and CO2 continues the warming , which produces more CO2 (See 2) which continues warming.”
    4) Further orbital changes cause the temperature to drop, even while CO2 is high.”

    “the temperature rise stops, and CO2 continues the warming ”

    Aerm come again?

    In general your hypothesis also seems to have a fundamental problem .

    Both the rise and the fall of temp/CO2 is initiated by a short orbital change? When this orbital interaction is over, then the temp/CO2 interacts so that we get a further rise or fall in temp/CO2?

    So.

    When there is no outside orbital interaction,
    1) during the rise this temp/CO2 system tends to rise all by itself?
    2) during the fall this temp/CO2 system tends to fall all by itself?

    I believe this earth system without an external interaction should seek ONE equilibrium and one only.

    Dont believe all you hear from IPCC. :-)
    This hypothsis is totaly NOT likely and NOT proved in any way!

  196. Chris – According to UAH, global temperature from Jan 1990 to Jun 1991, i.e. the month Pinatubo erupted, averaged +0.12C.

    Hmmm, The effects of Pinatubo would not be evident immediately in the global mean so I wonder why you chose a rather unusual 18-month mean, rather than say,the average for 1990? 1990 starts at month 132 here. Ah now it becomes clearer. Naughty.

    One does not measure a trend in a noisy signal by examining just the start and end, a least squares fit of all the UAH monthly data points from Jan 1990 gives a trend of 0.17C to 2 dp, right on the IPCC money.

    As to the near future, well that is weather rather than climate, however the IPCC projection would give average UAH anomalies for 2010 of around 0.42C, an increase of 0.26C over the most recent monthly figure. A tall order, possibly, until one remembers that in the 2 years leading up to the 1998 El Nino, UAH temperatures trended up at 0.26C a month.

    Fun with numbers!

  197. Kim lucia’s Blackboard at rankexploits.com for the truthseekers out there.

    Lucia examines the IPCC projections vs observations over a clmatically-significant period here

    From the intro .. What’s the best way to convince skeptics warming is real?

    Visiting may blogs and forums, I have developed an impression some believe the best way is to snark, scream, and throw tantrums, deny anything could look the slightest bit contrary to any consensus warming claim for even a mili-second.

    I think a better way is to show data over time and let people watch how things evolve. I think it’s paticulary important to admit that some claims aren’t currently supported with any great confidence and to show that occasionals outliers arise. In that light, I compare IPCC projections to data, and will continue to do so. The fact is, I’m confident we will see warming. I seriously doubt it will be 2C/century between now and 2030. But who knows? I could be wrong. If so, I’ll be posting regularly, and people will see the temperatures turn.

    cheers,

    JP.

  198. John Philip.

    Are you simply trying to be provocative. I’ll try and reply simply and to the point without a rant.
    You are the one who picked the 1990 starting point:
    ““The IPCC projected that temperatures would rise at an average of around 0.175C / decade from 1990-2010. According to the UAH satellite record the actual rate was 0.174C /decade.”
    In order to compare like with like, you have to adjust for ENSO as I did.
    I went as far as I could from Jan 1990 before I got to the Pinatubo eruption.
    Look at the UAH figures from Jul 1991: 0.20, 0.22, 0.07, -0.04, -0.10 and so on, eventually down to a low of -0.39 in Aug 1992. And what state was ENSO in during that time? El Nino! (Peaking from Oct 91 to Jun 92)

    Your reference to El Nino 1998 is irrelevant because it was in the middle of the 16-year period which we’ve already established had a (UAH) trend of 0.106C / decade, adjusted for ENSO and Pinatubo. This would suggest that if we have an equivalent El Nino in say 2010, the 16-year trend from 2004-2020 should be similar. What you need is a Super El Nino+++ to achieve the acceleration in trend you require. And where do you suppose all that triple-hot water is currently hiding?

    I can’t believe I even wasted my time replying to this. Sorry, it’s late and I’m in a bad mood. And you seem like the type to play clever games so you’ll probably try and confuse the issue or provoke some more. Fine. What are you trying to prove. Convince people that the properly adjusted trend is nearly twice what it actually is. Fine. Does the truth matter? Maybe it doesn’t if global warming really is soon to triple in speed and people need convincing of it at all costs. Or does the truth always matter…..

    Well I did rant in the end.

    Actually, just thought, to be fair, maybe you don’t understand ONI (re: your strange “naughty” comment. Go and look it up.

  199. Since Dr. Meier mentions elephants, here’s an elephant we should watch out for:


    The mathematical physicist v. Neumann once said to his young collaborators: “If you allow me four free parameters I can build a mathematical model that describes exactly everything that an elephant can do. If you allow me a fifth free parameter, the model I build will forecast that the elephant will fly.”

    from “Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame of Physics” by Gerlich and Tscheuschner,
    http://arxiv.org/PS_cache/arxiv/pdf/0707/0707.1161v3.pdf

  200. O.M.G…. I CANNOT believe this assertion:

    “Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate.”

    Was he serious? Is he really a scientist? One must disprove everyone else’s theories before promulgating or proving their own?

    OK….. by that logic, here’s my tongue-firmly-in-cheek assertion ….
    ANY EXPLANATION THAT AGW IS CAUSED BY ANYTHING OTHER THAN WHATEVER CAUSED THE MWP MUST FIRST INCLUDE AN ARGUMENT FOR WHY AND HOW THAT WHATEVER CAUSED THE MWP IS NOT AFFECTTING THE CLIMATE THE WAY THAT IT AFFECTED THE CLIMATE LAST TIME.

  201. O.M.G…. I CANNOT believe this assertion:

    “Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate.”

    Was he serious? Is he really a scientist? One must disprove everyone else’s theories before promulgating or proving their own?

    OK….. by that logic, here’s my tongue-firmly-in-cheek assertion ….
    ANY EXPLANATION THAT AGW IS CAUSED BY ANYTHING OTHER THAN WHATEVER CAUSED THE MWP MUST FIRST INCLUDE AN ARGUMENT FOR WHY AND HOW THAT WHATEVER CAUSED THE MWP IS NOT AFFECTTING THE CLIMATE THE WAY THAT IT AFFECTED THE CLIMATE LAST TIME.

  202. John Philip says

    “The effects of Pinatubo would not be evident immediately in the global mean…”

    I dont agree, check this:

  203. Chris, No, I did not pick the 1990 start point – that was the IPCC baseline. The IPCC made several projections, clustered around an increase of around 0.35C by 2010, a linear trend of approx 0.175.C/decade.

    Fitting a linear trend to the actual data 1990-now using OLS gives 0.17C .decade. No need to ‘adjust’ for anything. This uses all the available data rather than (carefully) selected groups of points at the start and end of the period and so gives a statistically superior estimate of the actual trend. Sorry, but there it is.

    JP.

  204. John Philip (08:07:47) :

    I am using the climatological definition of ‘recent’. The IPCC projected that temperatures would rise at an average of around 0.175C / decade from 1990-2010. According to the UAH satellite record the actual rate was 0.174C /decade.

    What’s that definition?

    I see about 0.17 K/decade between 1990 and 2000, much less since 2000.

    http://woodfortrees.org/plot/uah/from:1990/plot/uah/from:2000/trend/plot/uah/from:1990/to:2000/trend

  205. John Philip (16:09:46) Particularly note “I think it’s particularly important to admit that some claims aren’t currently supported with any great confidence”

    And I agree with lucia, time and data will tell. What are they telling us now?
    ========================================

  206. I concur with many of the above posters. Dr. Meier, your explanations are very well put, and you have good points, but your primary premise is faulty because it is based on the post-hoc and the negative proof logical falacies.

    The problem is that there is no evidence that CO2 is responsible for the warming. Previous warming anomalies show that natural variability exists on the same scale as current warming, so we cannot eliminate natural causes as the source of current warming. More importantly, the southern hemisphere has shown no warming at all. As greenhouse gas warming is a global phenomenon that should be more-or-less even planetwide, this is a very large piece of evidence that the warming is not caused by greenhouse gases.

    Finally, the fact that we cannot prove that it is natural does not mean that it is man made. As a scientist you must know that in a situation without conclusive evidence, no conclusion can be drawn. Whether the uncertainty merits action on climate change legislation is a matter of debate, but do not foist a negative proof on us as evidence.

  207. I noticed that several people have cautioned that the “Csomic Ray influence, on cloud formation ; has not been proven; has only worked in the laboratory; etc etc.

    Well “global warming” by CO2 has NEVER been proven, in fact all the long historic “data” says that global warming causes atmosperic CO2 to change and not the reverse.

    The cosmic ray/charged particle “effect” is a lot more compolicated than just being the sole cause of cloud formation.

    A result of the solar magnetic flux changes, that accompany sun spot cycles is more than just the global flux of such particles.

    The magnetic fields that accompany sun spots reverse every 11 1/2 years,sp the magnetic cycle is 23 years. So far as I know, the earth magnetic field does not reverse in synchronism with the sunspots, so in one sunspot cycle the vector sum of the solar magnetic field, and the earth magnetic field, is quite different, and a 23 year climat/sunspor linkage has been observed, but not an 11 year effect.

    In addition to just the total cosmic rays striking the earth, a significant effect of the local magnetic field, is that cosmic ray and solar charged particles are steered selectively by the fields. Particularly the lower energy charged particles lock onto the local magnetic field and spiral around the field lines to end up striking the atmopshere, in the regions of the magnetic poles; which is well known as the origin of aurorae in the polar regions. So what ?!.
    Well as everybody knows, the polar regions are cold, and the tropical regions are hot, so water vapor in the atmopshere tends to be concentrated in the warmer regions, and scarce in the polar regions. So anything that steers charged particles around alters the cloud formation, because in the tropics, there’s much more water to nucleate. Cosmic rays concentrating near the poles have little water vapor to work with, and lower relative humidities too.

    Don’t look for a bold effect that stands out like a sore thumb like the Mauna Loa annual CO2 6 ppm amplitude cycle.

    Global cloud cover has only been observable since the first polar orbit satellites went up circa 1979, so albedo effects of clouds, and the growth and loss of polar ice sheets, it a relatively young quantitative study. And I can’t imaging how ground based global cloud studies can even be conducted.

    But Wentz et al showed that a one degree C rise in global surface mean temperature (whatever that is) causes about a 7% rise in global evaporation, and a 7% rise in total atmospheric water vapor; and also a 7% rise in global precipitation. Of course precipitation tends to happen somewhere else from where the evaporation happens, and at some other time, but they have to equalize; and precipitation means DARK clouds, that can’t really be studies quantitatively from satellites, although albedo effects can.

    So I take statements that there is no link between cloud cover and global temperatures with a grain of salt.

    No, I am not a researcher in this field, and I have to take the reported data that others gather, and try to find some sense in it. You might have noticed I try to find some way of explaining it in temrs that any 8th grade high school science student can grasp. Doesn’t matter if scientists can understand it; if the public, and the politicians can’t understand it, then they will believe any story the AGWers give them. I don’t have any axes to grind; I don’t and never have worked for any energy/resource development company, nor do I invest directly in their stocks or their products. So I buy gasoline, and maybe my 401K fund, invests in energy behind my back.
    Neither do I swill at the public trough and constantly beat up on the tax payers to keep funding my research. Have you noticed the government generally doesn’t fund studies to show ansolutely nothing untoward is happening; so researchers know that is not a fruitful line of research. I have a friend lawyer, whose specialty is defending doctors against medical mal practice suits; and he makes good money at it. His clients are well heeled insurance companies who can afford his fees; and his experience is that a very large fraction of malpractice suits are simply fraudulent; which is not to say malpractice doesn’t occur. He doesn’t take those cases.
    Bank robbers rob banks, because that is where the money is.

    So all I care about is that we get the science correct, and we do so, before we actually destroy this planet, both ecologically, and economically.

    No cosmic rays/solar particles are not the be all and end all of climate; but they do amplify the effect of solar activity, as it manifests in sunspot cycles; and anything including dust, that enhances cloud nucleation leads to cooling, and anything that inhibits cloud formation leads to warming.

    I leave it to those wh do do field research in these areas to put some meat on the bones.

    But frankly, as a physicist and mathematician, I would not want to have to try to defend the AGW climate thesisi.

    When I went to school, any thesis that claimed the cause (CO2) of some effect (global warming), actuaally happend as much as 800 years after the effect has happened, would be a statutory bar to that theory. Today in this internet blog world it is just a ho hum. Yes I do understand the infra-red spectroscopy mechanism of molecular absorption as in the CO2 molecule; and I understand how that can result in heating of the very surface of the planet; which is 73% water; and at that point the water cycle takes over. The exact quantitative aspects of that relationship, I will leave to thiose in the field; but the mechanismis unavoidable.
    I’m also an analog circuit designer of long standing, so I understand exactly how feedback works; and it is physically impossible for the input signal (cause), to happen after the output signal (effect); if for no other reason, that energy processing systems must have a propagation delay.

    The claimed CO2/ water feedback system is in my view just nonsense; bcause feedback systems, actually have a time response as well, and the delays in climate systems are such, that these feedback systems would oscillate wildly, if these feedback were really there. Feedback amplifiers tend to go into limit cycle rail to rail oscillations, if the delays are excessive for the amount of feedback; and you don’t see too many climate systems that are in oscillation. The Mauna Loa CO2 signal is not an oscillation, but a clear result of the driving input signal that is linked to the rotation of the earth, and its orbit around the sun.

    I’ve seen a lot of “climate papers” that talk about “forcings” and “feedbacks”, but I’m still waiting for such an analytical paper that includes the time response of that system.

    Well the trouble with computer “GCMs”, is that they may be climate models; but they certainly aren’t models of the climate of any planet in our neighborhood. The idea that a mean global temperature exists all over the world, instead of a daily temperature spread that can be as much as 150 deg C, and that the earth radiates at a constant 390 Watts per square meter, from pole to pole 24/7, per the official NOAA energy budget diagram is just silly.
    Averaging the measured temperatures at various points on earth at various times, makes almost as much sense as averaging all the telephone numbers in the Manhattan phone book, and claiming that is the mean NYC telephone number. those temperatures are all differnt, because they are supposed to be; and their average has no scientific meaning or validity whatsoever.

    Dr James Hansen’s GISStemp anomaly plot, is a graph of the GISStemp anomaly; and nothing else. Every point plotted on that graph, was measured nowhere at any point in time, by anybody; it is simply the manufactured output of applying some unknown algorithm, to some unknown and closely guarded secret set of raw data; whose long term history integrity is highly suspect.

    Likewise HADcrut, and RSS, and UAH, are simply plots of other algorithmic outputs from other raw data sets done by other people. All of them are interesting relative to other data points on the same page; but they don’t agree with each other, which is all the proof that you need, that none of them is likely to be an accurate measure of anything like a mean global surface temperature. they don’t have any meaning at all other than on that page they are plotted on.

    We don’t have any sound practical method to measure a real global mean surface temperature; and in the unlikely event we came up with a method; the result would still be meaningless, because energy gains and losses from the earth have no simple relationship to any such number. Just the radiative losses from the earth are more related to the fourth power of temperature; so even the mean 4th power of temperature would be more meaningful; but still useless because each differnt terrain type, has totally different thermal processes.

    The John Q Citizen public takes GISStemp as the gospel truth mean global surface temperature, even though it is labelled an anomaly, which presumably means it is always wrong if it isn’t zero. They can’t even give it a real temperature scale value, because it is referred to some other mean number over some period of time, during which they were also unable to measure the mean temperature of the earth.

    That is not my idea of science, when we discard the Newtonian theory of gravity, in favor of Einstein, all because we found that the precession of the perihelion of Mercury was off by 43 lousy seconds of arc per century, from what Newton said it should be. We don’t abide physical theories that have glaring discrepancies between theoretical (modelled) predictions, and actual experimentally observed data.

  208. I’m still having trouble understanding these positions:

    “…I do not understand Dr Meier’s starting position to be anything other than a recognition of that (entirely rational) proposition. So, when he asserts that it is for those arguing against AGW to prove their case he is saying: “Look chaps, we know we are putting more of the heat-making stuff up there so you tell me why our extra heat-making stuff isn’t making extra heat.”..”

    As I said earlier, we don’t know how strong the ‘heat-making’ (sic) stuff is. A major plank of the warmers argument is that it’s strong – the deniers say it’s weak. With that as the point at issue, you can’t just assume it’s strong and then say to your opponent “Where’s the extra heat? “. The deniers argument is that there ISN’t any….

    “It may be that AGW is so small as to be insignificant, but that is a world away from saying it does not exist at all.”

    Ummm. In theory you are right. Something that is insignificant still theoretically exists. But in terms of the AGW argument something that provides an insignificant rise in temperature, which is too small to be measured, does NOT exist in any practical sense, and it is a reasonable comment to say this. Otherwise we will have to keep on referring to the extra global warming we cause on the soles of out feet when we walk across the room…

    “…the predicted temperature rise due to that forcing, summarised in IPCC AR4 WG1 Section 9.6 which give an expected increase in temperature, after a doubling of CO2e, in the range 2-4.5C. As this is consistent with recent observations, his point is that the onus is on those who propose a purely natural and alternative explanation to provide a mechanism (solar, ocean circulation changes, or Factor X) that would explain the warming, and explain why the radiative forcing of the increased GHGs is not having the predicted effect…”

    Again, the hidden assumption here is that because I can correlate CO2 increase with temperature in a model, the one must be causing the other. The correlation falls down in recent years, so most appropriate thing to say is that it must not have been an accurate assumption to start with. Instead, this strange position takes the 20 years of correlation as proof that this is a causual relationship, and then tries to defend the relationship when it fails by saying that since some heat is missing, your opponents must find it before they can continue the discussion.

    It’s NOT there! And the fact that it’s not there is the fact that breaks the concept of AGW.

  209. George E. Smith (12:19:31) :
    The magnetic fields that accompany sun spots reverse every 11 1/2 years,so the magnetic cycle is 23 years. So far as I know, the earth magnetic field does not reverse in synchronism with the sunspots, so in one sunspot cycle the vector sum of the solar magnetic field, and the earth magnetic field, is quite different, and a 23 year climate/sunspot linkage has been observed, but not an 11 year effect.
    Except that is not the way it works. The solar magnetic field is drawn out in interplanetary space by the solar wind, but the field there [the IMF - interplanetary magnetic field] changes polarity [into the Sun or away from the Sun] every 7 days on average. The north-south part of the IMF changes every few hours. None of these changes have anything to to with any climate/sunspot linkage on the the timescale of decades or years.

    Global cloud cover has only been observable since the first polar orbit satellites went up circa 1979, so albedo effects of clouds, and the growth and loss of polar ice sheets, it a relatively young quantitative study
    Cosmic rays and solar wind particles to first other do not change on a 23-year cycle, but on an 11-year cycle. The cloud cover http://www.leif.org/research/cloud-cover.png and albedo http://www.leif.org/research/albedo.png do not show any 11-year period.

    And I can’t imaging how ground based global cloud studies can even be conducted.
    Well, other people can. The cloud cover and the resulting albedo are closely related. There are observational programs running right now that measure the Earth’s albedo by measuring how bright the Earthshine on the Moon is.

    So I take statements that there is no link between cloud cover and global temperatures with a grain of salt.
    And to accept that there is a link requires not just a grain but a whole bag of salt.

    cosmic rays/solar particles are not the be all and end all of climate; [...]I leave it to those wh do do field research in these areas to put some meat on the bones.
    So far, the bones have been hard to come by.

    I do share your frustration, but one does not combat bad science with worse science.

  210. @Ron:

    O.M.G…. I CANNOT believe this assertion:

    “Any natural-causes explanation must be accompanied by an argument for why and how human-caused greenhouse gases (GHGs) are not affecting climate in the same way that natural GHGs affect climate.”

    Was he serious? Is he really a scientist? One must disprove everyone else’s theories before promulgating or proving their own?

    I think you did not understand Dr. Meier. He did not mean that you must disprove his hypothesis to to prove your own.

    He ment that in order to prove your own hypothesis about climate change, you must take ALL known and relevant physics into consideration. The IR absorption of CO2 is relevant to any hypothesis concerning climate change. This is even more true if this hypothesis sets out to disprove the rising CO2 level as the cause of climate change! Physics do not take sides.

  211. @George E. Smith,

    Your posts are very long and hard for me to follow, so I will not react to everything in them. But this has me puzzled:

    I’m also an analog circuit designer of long standing, so I understand exactly how feedback works; and it is physically impossible for the input signal (cause), to happen after the output signal (effect); if for no other reason, that energy processing systems must have a propagation delay.

    I think you forget that there is a third element involved: orbital changes. This triggers the increase of temperature, which increases the amount of CO2, causing the temperature to rise more. In the context of this mechanism CO2 is a feedback.

  212. Leif (15:45:33) on 20/10. Do you have any idea what causes the shape of solar cosmic rays around maximum to alternate solar cycles from peaked to rounded? Also, have Bill Livingston’s measurements of the magnetism of the last few spots fallen within the range of the decline curve to 2015?
    =============================================

  213. I think I’ve never heard so loud
    The quiet message in a cloud.

    Still louder, now, but still and all
    Still ’tis shadows on a wall.
    ============================

  214. I am looking at the FAQ 2.1 Figure 2 from IPCC Working Group I Fourth Assessment Report, 2007 that Dr. Meier referenced for Radiative Forcing of Climate between 1750 and 2005. Am I reading this graph correctly? — we would still be in the Little Ice Age if not for the anthropogenic contributions to warm up the planet starting in 1750! Natural variations are insignificant in relationship to what humans have done, so when glaciers started to retreat in the 18th century, that was due to human burning of fossil fuels. There might have been variations in climate before 1750 (as evidenced by what retreating glaciers uncover), but since 1750, it has been humans that have caused climate change. On another blog, a pro-AGWer confirmed the intepretation of the graph that humans have driven climate for the past 260 years.

  215. A question for Dr. Meier:
    In pre -000 pictures of Arctic ice cover, snow is not part of the picture and we see ice area extending into fjords, etc. In the pictures of the the last few years, we do not see this ice cover, rather the area shows up as snow. Did previous years’ ice area (and extent) get credited with ice-covered fjords while current year’s ice are (and extent) not get credited? Or has this issue been taken care of?

  216. An Inquirer (12:52:26) :
    Natural variations are insignificant in relationship to what humans have done, so when glaciers started to retreat in the 18th century, that was due to human burning of fossil fuels.

    Anthony – This post is a joke, right? Or, do people post on old blogs in an attempt to get the last word in?

  217. Tim Clark:
    Actually not a joke. This blog had the FAQ 2.1 Figure 2 from IPCC Working Group I Fourth Assessment Report. How else do you interpret the message of human vs. natural impact on climate on that Figure? Perhaps one can challenge the data on Figure 2 — but who has done that? Or, one can wonder if climatologists are missing key pieces to the climate puzzle (such as reality) by their Radiative Forcing of Climate.

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