Guest post by Bob Tisdale
OVERVIEW
This post compares satellite-based Sea Surface Temperature (SST) anomalies to the hindcasts and projections of the multi-model mean of CMIP3 models. CMIP3 is the archive the IPCC used as the source of their models for AR4. The period being discussed runs from November 1981 to November 2011. This covers most of the recent warming period that began in the mid-1970s.
There are two modes of natural climate variability discussed in this post: the El Niño-Southern Oscillation (ENSO) and the Atlantic Multidecadal Oscillation (AMO). For those new to ENSO, refer to An Introduction To ENSO, AMO, and PDO – Part 1. And for those new to the AMO, refer to An Introduction To ENSO, AMO, and PDO — Part 2.
This post also illustrates the multiyear aftereffects of the 1986/87/88 and 1997/98 El Niño events on the Sea Surface Temperature anomalies of the Atlantic, Indian, and West Pacific Oceans. Those oceans cover approximately 67% of the surface area of the global oceans. I have presented the processes that cause the multiyear aftereffects of those ENSO events in numerous posts over the past few years, so they will not be discussed in detail in this post. For those interested in learning about those processes, I discussed them and illustrated them with time-series graphs and with animated maps of sea surface temperature anomalies and other variables, most recently, in a two-part series: ENSO Indices Do Not Represent The Process Of ENSO Or Its Impact On Global Temperature and Supplement To “ENSO Indices Do Not Represent The Process Of ENSO Or Its Impact On Global Temperature”.
NOTE: The data in this post have been adjusted for the effects of volcanic aerosols.
INTRODUCTION
In the recent series of posts that compare the IPCC hindcasts for 20th Century surface temperatures to observed surface temperatures (see here, here, here, and here), the only time period when models consistently agreed with observations was the late warming period, from 1976 to 2000. But even that is misleading, because it gives the incorrect impression that anthropogenic forcings such as Carbon Dioxide were responsible for the rise in surface temperatures. Illustrating the error in that assumption is relatively easy when Sea Surface Temperature anomaly data is adjusted for the impacts of major volcanic eruptions and when the global data is divided into two subsets: the East Pacific (coordinates of 90S-90N, 180-80W) and the Rest-Of-The-World (90S-90N, 80W-180). Refer to the map in Figure 1 for an illustration of those areas. And Figure 2 is a comparison of the Sea Surface Temperature anomalies for those two subsets.
Figure 1
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Figure 2
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DATA
The Sea Surface Temperature anomaly data used in this post is Reynolds OI.v2. It combines bias-corrected satellite observations for more complete coverage and in situ observations from buoys and ships. The Reynolds OI.v2 Sea Surface Temperature data covers the period of November 1981 to November 2011, or 30 years. The Reynolds OI.v2 data is available through the NOAA NOMADS website here. There is another reason why the Reynolds OI.v2 data is used in this post: Smith and Reynolds (2004) Improved Extended Reconstruction of SST (1854-1997)stated about the Reynolds OI.v2 data:
“Although the NOAA OI analysis contains some noise due to its use of different data types and bias corrections for satellite data, it is dominated by satellite data and gives a good estimate of the truth.”
The truth is a good thing.
We’ll also be using the multi-model mean of the Sea Surface Temperature data that was produced by the climate models in the CMIP3 archive, where CMIP3 stands for Phase 3 of the Coupled Model Intercomparison Project. CMIP3 is the archive the IPCC used as the source of climate model data for its 4th Assessment Report. The CMIP3 Sea Surface Temperature data, identified as TOS, is available through the Royal Netherlands Meteorological Institute (KNMI) Climate Explorer website, specifically at their Monthly CMIP3+ scenario runswebpage. We have discussed in the recent posts that the multi-model mean represents the natural and anthropogenic forced component of the IPCC’s climate model outputs. And during the period we’ll be evaluating, it is the IPCC’s contention that anthropogenic forcings are the cause of the rise in surface temperatures.
The last discussion about the data is how the adjustments were made to account for the volcanic aerosols. The observational and model mean data are adjusted for the effects of volcanic aerosols, which would have major impacts on how the data was perceived during and for a few years after the explosive volcanic eruptions of El Chichon (1982) and Mount Pinatubo (1991). To determine the scaling factor for the volcanic aerosol proxy, I used a linear regression software tool (Analyse-it for Excel) with global Sea Surface Temperature anomalies as the dependent variable and GISS Stratospheric Aerosol Optical Thickness data (Source ) as the independent variable. The scaling factor determined was 1.431. This equals a global SST anomaly impact of approximately 0.2 deg C for the 1991 Mount Pinatubo eruption. To simplify and standardize the adjustments I’ve applied the same scaling factor to both the observed Sea Surface Temperature data and the model outputs. And I used the same adjustments for all subsets. As you will see, it slightly overcorrects in some instances and under-corrects a little in others. But since the adjustments are the same for the model outputs and instrument-based observations, they have no impact on the trend comparisons.
EAST PACIFIC SEA SURFACE TEMPERATURE COMPARISON
Figure 3 compares the Sea Surface Temperature anomalies of the East Pacific Ocean (90S-90N, 180-80W) to the scaled Sea Surface Temperature anomalies of the NINO3.4 region of the equatorial Pacific (5S-5N, 170W-120W). NINO3.4 Sea Surface Temperature anomalies are a commonly used index of the frequency and magnitude of El Niño and La Niña events, and I’ve scaled them (multiplied them by a factor of 0.22) because the variations in Sea Surface Temperature in that area of the equatorial Pacific are about 4.5 times greater than those of the East Pacific Ocean. As illustrated, the Sea Surface Temperature anomalies of the East Pacific mimic the NINO3.4 Sea Surface Temperature anomalies.
Figure 3
Figure 4 compares the observed Sea Surface Temperature anomalies of the East Pacific to the CMIP3 Multi-Model Mean for the same coordinates. The first thing that stands out is the difference in the year-to-year variability. The observed variations in Sea Surface Temperature due to the ENSO events are much greater than those of the Multi-Model Mean. Keep in mind when viewing the model-observations comparisons in this post that the model mean is the average of all of the ensemble members. And since the variations in the individual ensemble members are basically random, they will smooth out with the averaging. The average, therefore, represents the forced component (from natural and anthropogenic forcings) of the models. And it’s the forced component of the model data we’re interested in illustrating and comparing with the observations in this post, not the big wiggles associated with ENSO.
Figure 4
The difference in the linear trends between the Multi-Model Mean and the observations is also extremely significant. That is the focus of this post. The linear trend of the Multi-Model Mean is 0.114 deg C per decade for the East Pacific Ocean. This means, based on the linear trend of the Multi-Model Mean, that anthropogenic forcings should have raised the East Pacific Sea Surface Temperature anomalies, from pole to pole, by more than 0.34 deg C over the past 30 years. But the observed Sea Surface Temperature anomalies have actually declined. The East Pacific Ocean dataset represents about 33% of the surface area of the global oceans, and the Sea Surface Temperature anomalies there have not risen in response to the forcings of anthropogenic greenhouse gases.
THE REST-OF-THE-WORLD COMPARISON
The Sea Surface Temperature anomalies and Multi-Model Mean for the Rest-Of-The-World (Atlantic, Indian, and West Pacific Oceans) from pole to pole are shown in Figure 5. The linear trend of the multi-model mean shows that the models have overestimated the warming by about 23%.
Figure 5
But even that is misleading, because the observed Sea Surface Temperature anomalies only rose in response to significant El Niño-La Nina events, and during the 9- and 11-year periods between those ENSO events, the observed Sea Surface Temperatures are remarkably flat. This is illustrated first in Figure 6, using the period average Sea Surface Temperature anomalies between the significant El Niño events, and second, in Figure 7, by showing the linear trends of the instrument-based observations data between the 1986/87/88 and 1997/98 El Niño events and between the 1997/98 and 2009/10 El Niño events.
Figure 6
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Figure 7
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As you will note, I’ve isolated the significant El Niño events of 1982/83, 1986/87/88, 1997/98, and 2009/10. To accomplish this, I used the NOAA Oceanic Nino Index (ONI) to determine the official months of those El Niño events. There is a 6-month lag between NINO3.4 SST anomalies and the response of the Rest-Of-The-World SST anomalies during the evolution phase of the 1997/98 El Niño. So I lagged the ONI data by six months and deleted the Rest-Of-The-World SST data that corresponded to the 1982/83, 1986/87/88, 1998/98, and 2009/10 El Niño events. All other months of data remain.
Note: The El Niño event of 1982/83 was counteracted by the volcanic eruption of El Chichon, so its apparent role in the long-term warming is minimal.
And what do the climate models show should have taken place during the periods between those ENSO events?
For the period between the 1986/87/88 and the 1997/98 El Niño events, Figure 8, the model mean shows a positive linear trend of 0.044 deg C per decade, while the observed linear trend is negative, at -0.01 deg C per decade. The difference of 0.054 deg C per decade is significant.
Figure 8
The difference between the linear trends is even more significant between the El Niño events of 1997/98 and 2009/10, as shown in Figure 9. The linear trend of the observations is basically flat, while trend of the models is relatively high at 0.16 deg C per decade.
Figure 9
Keep in mind that the model mean, according to the IPCC, represents the anthropogenically forced component of the climate models during the period of 1981 to 2011. Unfortunately for the models, there is no evidence of anthropogenic forcing in the East Pacific Ocean Sea Surface Temperature data or in the Sea Surface Temperature data for the Rest Of The World.
Let’s subdivide the Rest-Of-The-World data even more. This will illustrate why the Sea Surface Temperature anomalies between the significant ENSO events are flat.
THE NORTH ATLANTIC AND THE SOUTH ATLANTIC-INDIAN-WEST PACIFIC SEA SURFACE TEMPERATURE ANOMALY DATA
Figure 10 is a map that shows how the data for the additional discussions were subdivided. Basically, this was done to isolate the North Atlantic from the additional ocean basins in the Rest-Of-The-World data. And the observed Sea Surface Temperature anomalies for those two subsets are shown in Figure 11. As illustrated, the linear trend of the North Atlantic Sea Surface Temperature anomalies is significantly higher than the linear trend of the South Atlantic-Indian-West Pacific subset. This higher trend in the North Atlantic data is caused by the additional mode of natural variability known as the Atlantic Multidecadal Oscillation. And as we will see, the forced component of the models (the model mean) does not account for the additional variability in the North Atlantic attributable to the Atlantic Multidecadal Oscillation.
Figure 10
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Figure 11
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Note: The North Atlantic Sea Surface Temperature anomalies for datasets like the Atlantic Multidecadal Oscillation data are normally depicted by the coordinates of 0-70N, 80W-0. Here they include 0-90N, 80W-40E to capture the Mediterranean Sea and corresponding portion of the Arctic Ocean leftover from the other subsets. The additional surface area has little impacton the North Atlantic Sea Surface Temperature anomaly data presented here. But to differentiate it from the other versions of the North Atlantic data, I’ve called it “North Atlantic Plus” in the graphs.
“NORTH ATLANTIC PLUS” COMPARISON
The North Atlantic is the only ocean basin where the models underestimate the long-term trend of the satellite-era Sea Surface Temperature data. See Figure 12. (Also refer to Part 1 and Part 2of an earlier two-part post comparing the Reynolds OI.v2 Sea Surface Temperature dataset to the same CMIP3 Multi-Model Mean, but note that the data in those posts have not been adjusted for volcanic aerosols.) Based on the linear trends, the models have underestimated the warming of the North Atlantic by nearly 35%. Again, the North Atlantic has an additional mode of natural variability called the Atlantic Multidecadal Oscillation or AMO. It seems very obvious that the multi-model mean fails to hindcast and project this additional variability.
Figure 12
And for those interested, I’ve also provided graphs that compare the model mean and observed trends between the significant El Niño events. As shown in Figure 13, the models underestimate the warming that took place between the El Niño events of 1986/87/88 and 1997/98. And as illustrated in Figure 14, the models overestimated the rise in North Atlantic Sea Surface Temperatures between the 1997/98 and 2009/10 El Niño events.
Figure 13
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Figure 14
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Let’s take a look at the South Pacific, Indian, and West Pacific comparison. As many of you are aware, I like to save the best for last.
SOUTH ATLANTIC-INDIAN-WEST PACIFIC COMPARISON
Figure 15 compares long-term observed Sea Surface Temperature anomalies and the Multi-Model Mean for the South Atlantic, Indian, and West Pacific Oceans. This is basically the portion of the “Rest-Of-The-World” dataset that is not included in the “North Atlantic Plus” data. As illustrated, the trend of the Multi-Model Mean is about 62% higher than the trend of the observed data. That is, the forced component of the models has over predicted the rise in Sea Surface Temperature anomalies for this subset by a substantial amount.
Figure 15
But the long-term trends are again misleading. The South Atlantic-Indian-West Pacific Sea Surface Temperature anomalies only rise during the significant El Niño events of 1986/87, 1997/98, and 2009/10. Between those events, the Sea Surface Temperature anomalies drop.
Figure 16 compares the observed South Atlantic-Indian-West Pacific Sea Surface Temperature anomalies to the Multi-Model Mean between the 1986/87/88 and 1997/98 El Niño events. The anthropogenic forcings have driven the model-mean upwards during this period, but the linear trend of the observations show that Sea Surface Temperatures declined. And the difference of 0.093 deg C per decade is a major difference. But that’s small compared to the difference between the linear trends of the observations and the model mean for the period between the El Niño events of 1997/98 and 2009/10. That difference is almost 0.18 deg C per decade.
Figure 16
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Figure 17
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CLOSING COMMENT
As illustrated in the two earlier posts that use these same datasets (see here and here), the Multi-Model Mean of the CMIP3 coupled ocean-atmosphere climate models do not hindcast and project the Sea Surface Temperature anomalies in any ocean basin, when the data is presented on times-series basis and on a zonal mean (latitude-based) basis. (The model mean of the West Pacific subset may look good on a time-series basis, but not on a zonal mean basis.)
This post confirms the Multi-Model Mean (the forced component of the climate models) does a poor job of hindcasting and projecting the actual rise in global Sea Surface Temperature anomalies, when the data is broken down into two logical subsets: the East Pacific Ocean and the Rest-Of-The-World. The post also illustrates the very basic reasons for that rise.
The models used by the IPCC for their hindcasts and projections assume that anthropogenic greenhouse gases drove the rise in Sea Surface Temperature anomalies from November 1981 to present. This is illustrated by the model mean, which represents the forced component of the models.
But the Sea Surface Temperature anomalies of the East Pacific Ocean (90S-90N, 180-80W) have not risen in 30 years. Refer to Figure 18.
Figure 18
And for the Rest-Of-The-World (90S-90N, 80W-180), Figure 19, the Sea Surface Temperature anomalies only rose during, and in response to, the 1986/87/88, 1997/98, and 2009/10 El Niño events.
Figure 19
There is no evidence that anthropogenic greenhouse gases have had any impact on the East Pacific Sea Surface Temperature anomalies (90S-90N, 180-80W) or on the Sea Surface Temperature anomalies for the Rest Of The World (90S-90N, 80W-180).
ABOUT: Bob Tisdale – Climate Observations
SOURCES
The model mean data is found at the KNMI Climate Explorer Monthly CMIP3+ scenario runs webpage. The Reynolds OI.v2 Sea Surface Temperature anomaly data is available through the NOAA NOMADS website here. And the GISS aerosol optical depth data used to make the adjustments for volcanic aerosols can be found at the Stratospheric Aerosol Optical Thickness webpage, specifically this data.
Dennis Ray Wingo says: “I know that this is asking for rank speculation but here goes. After the MWP and the transition to LIA conditions, what would you expect this step function to look like?”
Sorry, I don’t speculate about these effects. I use satellite-era Sea Surface Temperature data (1981 to now) to illustrate them because it is as close to being sptially complete are we’re likely to see.
Regards and enjoy your holidays
Solomon Green says: “Why eliminate volcanic activity? (Is there any reason to suppose that volcanic activity will not continue or does is the noise prvided by volcanoes too great and too erratic)? ”
For this post, the volcano adjustment, primarily, reduces the dip and rebound in the Sea Surface Temperature data (observed and modeled) that occurred in response to the 1991 eruption of Mount Pinatubo. It impacts the appearance of the data very strongly then. Compare Figure 7 above with a graph of the same data without the volcano adjustments:
http://i43.tinypic.com/2prw61e.jpg
The adjustment also has a small impact on the linear trend analyses between the 1986/87/88 and 1997/98 El Niño events. The observed trend for that period with the adjustments (Figure 7) is -0.01 deg C per decade, while the trend without them (link above) is slightly positive at 0.02 deg C per decade. (As noted in the post, since the models and observations are adjusted by the same amount, those are a wash.) The eruption of El Chichon also impacts the data from 1982 to 1985. And the adjustments also correct for it, but we’re not doing any short-term trend analyses during those years, because the period from the 1982/83 El Nino to the 1986/87/88 El Nino was just too short.
You asked, “Also how is subsea volcanic activity eliminated – particularky that of so far undetected volcanoes?”
Sorry for not being clearer on that. The volcano adjustments use stratospheric aerosol optical thickness data, because those volcanic aerosols reduce the amount of sunlight that reaches the Earth’s surface, thereby cooling the planet for a couple of years. There are no adjustments for subsea volcanoes.
Regards and enjoy the holidays.
Solomon;
The general principle would be that you “correct” for all known factors in order to find out how much variation is left which may be (or may not be) attributed to the phenomena you’re exploring. Volcanic events have the advantage of being “events”, so it is feasible to look for and remove their specific signals.
Bob Tisdale says:
December 19, 2011 at 4:44 pm
John B says: “The is no rationale behind the assumption that El Nino events cause a trend. For the opposite take on this, that a look at…”
Your statement indicates YOU do not understand ENSO, and that’s why I included links to the introductory post at the beginning:
http://bobtisdale.wordpress.com/2010/08/08/an-introduction-to-enso-amo-and-pdo-%e2%80%93-part-1/
…
And please don’t come back here with links to the nonsensical SkepticalScience posts that say that ENSO is a cycle and as such cannot contribute to a positive trend.
…
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Well Bob, it’s you against the rest of the world on that. The “O” does stand for “oscillation”, does it not?
To quote your introductory post:
“Many climate scientists treat the ENSO phenomenon as noise and assume that its signal can be easily removed from the global temperature record. I have written numerous posts about how and why this is incorrect.”
Yep, that’s what they think. If you think differently, you need to make a case for it, not just assert it.
This is good stuff Bob.
I think the Volcano-adjusted charts is the way to go. It is merely reflecting reality after all.
I more-or-less replicated your analysis and have done the same for the Lower Troposphere Satellite Temperatures. The linear trend then drops to 0.095C per decade (probably similar to your global SST value). The volcano-adjusted LT temperature trend would only be 40% of the climate model trend.
Bob T said:
“If and when I prepare an OHC model-observations post similar to this, then OHC would be the appropriate topic of conversation on that thread.
Now do you understand, what you called, my “insistence”?
_______
Your point has been made, but readers should understand that SST’s are a measure of heat flux in and out of the ocean, not a measure of the amount of energy the ocean is storing over a given period of time. If and when you want to engage in a discussion of OHC, I would welcome it.
Bob Tisdale says:
December 20, 2011 at 4:32 am
long pig says: “The observation of rest-of-world flatness between ENSO events is intriguing, though it would need more time to confirm. However – if it were the reality – the implications are profound.”
If there’s a question in your mind whether or not those upward shifts exist, please confirm them. The sources of the data are listed at the end of the post.
The data are fine, its just that this instrumental record is short, we have only 3-4 steps. Just being cautious – since this is a game-changer.
Not yours, I love your posts and I check it for new content every so often.
Stephen Wilde says:
December 20, 2011 at 6:33 am
“The key point here is that SST’s are not the key indicator for anthropogenic warming of the oceans, but rather OHC is, and is continues to rise throughout the full ENSO cycle over the long-term, and this is most certainly not a misleading trend.”
That assumes no variability in solar input to the oceans as a result of global cloudiness and albedo changes.
_________
Stephen, the fact that OHC has continued to rise across multiple ENSO cycles over 30+ years is not an “assumption”, and doesn’t presume anything about solar influences at all. It is a simple fact, without presumption as to cause. My entire reason for bringing up OHC is that is a much better metric for the heat being stored in the oceans than SST’s. SST’s measure heat flux or heat moving in and out of the oceans. When the SST’s are high, net heat is moving out of the oceans, and when SST’s are low, there is more net heat moving into the oceans. I always find it funny when people talk about the “cool oceans” during La Ninas, as in fact, all this means is that there is less heat at the surving moving out of the oceans into the atmosphere and this is actually the time when the oceans are absorbing more net heat.
If there is anything to Svensmark, I would be really interested to see how cloud cover might impact these events. For example, an El Nino during an active sun (as we had in 1998) vs an El Nino with a quiet sun (2010) what were the differences in cloud cover. Same with La Nina events. If we were to get a La Nina with more clouds we should get an even colder event (2008?).
@crosspatch says:
December 20, 2011 at 5:02 pm
“… an El Nino during an active sun (as we had in 1998) vs an El Nino with a quiet sun (2010)..”
`97/98 and `09/10 El Nino`s were both brought on by months of declining solar wind speeds:
http://omniweb.gsfc.nasa.gov/tmp/images/ret_13923.gif
@Dennis Ray Wingo says:
December 20, 2011 at 7:42 am
” After the MWP and the transition to LIA conditions, what would you expect this step function to look like? Fewer El-Nino’s with longer La Nina’s dragging the temps down more than an El Nino could overcome?”
Colder periods show an increase in the frequency of El Nino events.
Furthermore, the more important metric of energy in the oceans, Ocean Heat Content, shows large increases during the last decade when atmospheric temps have been flat. This of course makes sense, as La Nina’s have been more dominant over the past decade and it is during such periods that the oceans as a whole, retain more heat than they release to the atmosphere.
The argo OHC data doesn’t show large increases. The Argo OHC data shows limited ocean warming over the last 8 to 9 years.
Pre-argo data is of questionable value with very limited geographic sampling and known instrumentation issues.
It’s well accepted by climate scientists that there is not enough heat in the oceans to account for the supposed warming. Hence the ‘missing heat’ debate.
More importantly, the lack of ocean heat gain during La Ninas indicates La Ninas are driven in part by reduced heat entering the oceans.
R Gates what you need to explain is why the limited OHC gain during a period when La Ninas predominate?
R Gates;
You seem to be implying, without stating it specifically, that the air is warming the oceans. Do you really ‘believe’ that?
Philip Bradley said:
More importantly, the lack of ocean heat gain during La Ninas indicates La Ninas are driven in part by reduced heat entering the oceans.
——
There is no lack of heat gain to the oceans during La Ninas…quite the opposite. Remember the metric for measuring heat gain to the oceans is OHC, not SST’s. SST’s measure heat flux between ocean and atmosphere. Heat transfers out of the ocean to atmosphere during El Ninos, and that exactly what the higher SSTs are telling you.
———
Philip Bradley also said:
R Gates what you need to explain is why the limited OHC gain during a period when La Ninas predominate?
——-
Depends on what you mean by “limited”. Line up a chart showing OHC and ENSO over the past 30+ years and note the periods that OHC increases. It is during the La Nina periods or ENSO neutral, and the recent La Nina is no exception. But OHC has increased over this period as more heat has been gained by the oceans during La Ninas than lost during El Ninos.
Brian H says:
December 20, 2011 at 7:36 pm
R Gates;
You seem to be implying, without stating it specifically, that the air is warming the oceans. Do you really ‘believe’ that?
———-
Your next step I suppose will be to lecture me about LW radiation from the atmosphere not being able to penetrate the skin layer of the ocean. But to answer your question– no I do not believe that the atmosphere is warming the ocean, as that most certainly does not happen. The ocean is a far better energy sink than the atmosphere, and the direction of energy flow is predominantly from ocean to atmosphere, hence the reason that the atmosphere warms so nicely during s strong El Nino. The vast majority of energy on the ocean certainly comes directly or indirectly from the sun. But the issue with greenhouse gases and the oceans retention of energy is not about the excess heat in the atmosphere entering the ocean, but rather, the ability of the ocean to get rid of the excess heat it has. It is all about thermal gradients. When the atmosphere has a bit more heat in it, the the thermal gradient is a bit less steep, and so a bit less heat will leave the ocean and enter the atmosphere. Over time, the ocean heat content will gradually increase because of this lessening of the thermal gradient, and the OHC will increase. This is precisely what we’ve seen over the past 30+ years.
RG;
I think you’d have a hard time balancing a thermal flow equation for that process. The atmosphere’s specific heat and the “AHC” are trivial compared to the ocean’s specific heat and OHC. If anything, an acceleration of the evaporation/convection processes involving H2O seems like the only sufficiently robust and potent mechanism for removing “excess heat”. Completely aside from the issue of just where all that “excess heat” came from, and when, to begin with.
R. Gates says in reply to Pamela Gray: “Actually, this is completely backward. All things being equal, a period dominated by neutral to El Nino conditions should see a decrease in OHC, with a warming of the atmosphere as that heat is transferred there.”
And R. Gates says in reply to me: “The problem with this notion is that globally, oceans absorb more heat then they release during La Nina’s, thus OHC will increase during such a ‘step down’ cycle.”
Even though you have hijacked this thread with your OHC discussions, apparently because you did not want to discuss THIS post, I will reply ONE LAST TIME to your OHC comments:
Since all El Nino events are not equal, and since La Nina events are not the opposite of El Nino events, blanket “all things being equal” statements such as yours are likely to be wrong.
Actually, Pamela Gray did not have it completely backward, as you claim. It depends on the subset one looks at and a multitude of additional factors. Overlooking those additional factors for the sake of example, during a period when El Nino events dominate, tropical Pacific OHC would decrease. But the warm water that is released from below the surface of the Pacific Warm Pool and transported east along the equatorial Pacific during the El Nino, and that is not “consumed” by the El Nino, is then redistributed poleward in the Pacific and distributed into the Indian Ocean by the Indonesian Throughflow. This additional influx of warm waters into those basins would obviously raise OHC there.
Of course, your generalizations overlook the apparent impacts of the AMO/AMOC and of shifts in Sea Level Pressure on North Atlantic OHC, both of which had major impacts on the additional rise in the OHC there. Keep in mind that the North Atlantic contributes 40% to the long-term rise in Global OHC, even though it represents less than 15% of the surface area of the Global Oceans. Also keep in mind North Atlantic OHC has been dropping quite significantly over the past 5-6 years. And of course, your generalizations overlook the very obvious upward shift in North Pacific OHC caused by the late 1980s shift in Sea Level Pressure there. Prior to that change in SLP, the long-term trends of North Pacific OHC were negative. (There’s not a lot of AGW apparent when OHC is dropping, R. Gates.) These natural causes of the long-term rise in OHC are why I repeatedly link for you the following posts during discussions of OHC:
http://bobtisdale.wordpress.com/2009/09/05/enso-dominates-nodc-ocean-heat-content-0-700-meters-data/
And:
http://bobtisdale.wordpress.com/2009/12/30/north-pacific-ocean-heat-content-shift-in-the-late-1980s/
And:
http://bobtisdale.wordpress.com/2009/10/04/north-atlantic-ocean-heat-content-0-700-meters-is-governed-by-natural-variables/
Your persistent efforts to hijack this thread, steering the discussion away from the subject matter of this post (with your continued off-topic comments to Brian H, Philip Bradley, Stephen Wilde, Pamela Gray, and others), is very obvious to all who are reading your comments. The fact is, R.Gates, the coupled ocean-atmosphere climate models, upon which the IPCC and AGW proponents rely to confirm the impacts of the hypothesis of AGW, have no skill at hindcasting surface temperatures over the 20th Century (as shown in my recent series of posts), and no skill at determining the actual cause of the rise in SST over the past 30 years, as shown in this post. In other words, climate models to a very poor job of confirming the hypothesis of AGW. And without climate models, whatcha got?
Enjoy your holidays, R.Gates.
RockyRoad says:
December 20, 2011 at 8:36 am
Wait for the Warmistas to switch from “CO2 is causing Global Warming/Climate Wierding” to “CO2 is causing Global Cooling”, thereby taking another route to force reduction of CO2 worldwide.
Actually Rocky, this is already happening. I wrote about it recently at
http://wattsupwiththat.com/2011/12/10/last-minute-durbal-deal-reached-extends-kyoto-protocol/#comment-826281
…
Earth has already entered a natural cooling cycle, or soon will. The technical argument for cooling is receiving early-stage support from atmospheric and ocean temperature data. We will soon know if multi-decadal natural cooling has commenced. (BTW, I predicted such natural global cooling in an article published in 2003.)
There is also significant sociological support for global cooling. The global warming extremists are already scrambling to revise their manmade-fossil-fuel-burning-causes-runaway-global-warming hypotheses.
Some are saying that increased CO2 actually causes global cooling, not warming. Quelle surprise! Others are blaming humanmade aerosols for the lack of global warming – but they had to fabricate the aerosol data to support their case!
Both arguments are utterly specious. No matter – anything for The Cause!
…
Remember good people: Atmospheric CO2 LAGS temperature at all measured time scales.
Good work Bob. Thank you, and Merry Christmas to all!
R.Gates…
Appreciate your reply…its to your credit you did not ignore my question. Your answer though…bit of a half way step, and you then did a load of hand waving to imply that the hockey stick was not really important..but..er…it is important. It was so important it became the poster child for the IPCC and every other ‘alarmist’ for quite a while.
You see…without Manns hockey stick – and may I tweak your words to say you do actually agree with us that it was bogus science yes (despite your ‘error bars’ caveat!!!) – the question is….if it was warmer/as warm in the MWP, and we do not know why, should we not be a little cautious in assuming that poor old Sidney Poitier is the villain of the piece, just because he got off the train at the same time? And unless I’m mistaken, I don;’t know of any other reconstructions that are really valid (ie circular referencing the debunked Mannian stuff) that suggest there is any hockey stick at all? So……nothing to say what we have now is unusual at all, do you agree?
Whilst your theory of CO2 as a potent greenhouse gas is interesting and worth looking at, I would say that by now observational evidence would suggest that its role is minor, if not totally irrelevant.
Your theory states that we should by now have seen the hot spot over the tropics, we have not. Your theory states we should see quite a rise in OHC, but we have not (see Pielke Sn on his regular updates of where we should be regarding Hansons predictions of this). Have we seen anything worth looking at? Is it even of a significant value at all ? (Leaving Trenbeth to speculate that it somehow dodged the ohc temp capturing measurements on the way down to the deep deep..clutching at straws?). The only thing you still have going for your theory still is a drop in strato temps (but the science on that is vague..is it possible without the corresponding hot spot over the tropics? You have 2 contradicting statements there yes?)
That leaves us with thinning ice in the acrtic….thats really the only part of your theory that one could say is an observable fact. But of course….we also know the arctic varies, there is too much detail of drops in ice cover in living memory let alone distant past – is arctic ice just poor old Sydney getting thrown in jail again?
Anyway…glad to see you acknowledge that the temps we have now are not unusual. Now we can discuss other reasons for the temps, such as Bob suggests, and why CO2 may not be the driver you think it is?
“Something caused Sea Surface Temperature anomalies to drop significantly from the 1870s until 1910…
http://bobtisdale.files.wordpress.com/2011/12/figure-143.png
…and it wasn’t volcanic eruptions or solar according to the IPCC’s climate models”
The trend is there in the aa index: http://www.appinsys.com/GlobalWarming/AAIndex_files/image003.png
Bob Tisdale said:
” Is it? It has been a one-way street for a few recent decades. However, from the 1940s to the late 1970s, the frequency and magnitudes of El Nino and La Nina events were such that La Nina events dominated by a slight margin. Global surface temperatures did not rise.”
The cooling during that period was caused by anthropogenic aerosol: sulphates an incredible amount of SO2 was blown into the air. Once these emission started declining (because of regulations in Europe and US to stop the acidification processes) the temperatures started rising, as many West-European countries have experienced. (Even in this very year 2011: Austria has in 2011 it hottest year for the mountain regions on record, but on this website only a short spell of one-day snow in the middle of September was big news: a tiny cold spell in too hot months August -September. Belgium wil get its hottest year as well, and so other European areas will have)
From 2000 aerosol production world wide is rising again by the economic boom of Asia. Ignoring these influences on temperature development – and actually radiation budget – and claiming the rise and flattening has only to do with El Nino is pretty shortsighted. Although preparing the graphs seems to be nice work i must admit (with pleasure) the explanations need somewhat more balanced considerations.
Aerosol was not only spread by Pinatubo!!!
You could also – as some others bring up too – expect that after El Nino events the temperature should slowly drop back to its starting point, with eventually also some bigger steps caaused by La Nina. A bit strange that only El Nino’s would make steps and La Nina’s don’t. May be it is woven in the flattening after these El Nino’s.
Last point: ice,
Ice is disappearing and that takes energy, warmth. Northpole ice is not only loosing extent but also volume (as well as Greenland Ice sheet does). Temperature rise partly disappeared by the melt of a vast mass of ice. I don’t know how much energy it took in the equivalent of nonrising temperatures, maybe it is minor but then it would be nice to have stated that too in the analyses of the temperature trends.
I wish you all very warm feelings in 2012, alarming denial or not.
p.s. In Holland we will have the first December ever without one day of frost in the (normally) coldest part of the country even, CO2 + rest GHG or El Nino or one enhanced by the other, who will tell us in 2012?
Sorry fot the “Al Nino’s” if someone can correct these….
[REPLY: OK, zijn de AL Nino’s gezorgd, evenals een paar andere kleine fouten. Mijn Nederlands moet zo goed zijn. -REP]
Looking back to pre-satellite times, perhaps the best indicator of sea surface temperatures can be gauged from records kept for small islands in the middle of oceans, as these are strongly influenced by the surrounding sea surface temperatures.
According to IPCC projections, the Arctic is supposed to suffer the greatest warming – up to 8 degrees by 2100. That is why this Arctic Island* data is so interesting as it bears absolutely no resemblance to trends in carbons dioxide levels. http://climate-change-theory.com/JanMayen.jpg Notice the warmer period in the 1930’s.
There is also confirmation of the above warm period in this plot of general Arctic data since 1880 http://climate-change-theory.com/arctic1880.jpg Note the huge 4 degree rise from 1919 and 1939 – before WWII when carbon dioxide levels started to take off. For more detail see this web page http://www.warwickhughes.com/cool/cool13.htm
None of this is new data. It would have been available at the very time the IPCC was publishing their predictions that the Arctic would be affected more than any other place in the world. If ever there has been data to hit the AGW hypothesis hard on the head it would seem to be this.
* Jan Mayen Island is located here: http://www.climate-change-theory.com/JanMayenEarth.jpg
Scorle: You refer to ice melting in the Arctic. In fact the amount of melting (and reformation) of ice there appears to be determined by natural cycles in the North Atlantic, similar to the ENSO cycles. What happens is that the North Atlantic is of course the main “entrance” to the Arctic Ocean. Currents entering the Arctic region vary naturally in both temperature and rate of flow. (Ice melts more when the flow is faster.) It is these waters under the ice that contribute most to melting and reformation, not solar radiation which meets the ice at an acute angle and is mostly reflected. Least of all does it have anything to do with carbon dioxide for reasons outlined in my other posts.
Please see my post above and the links therein, where you will note that the Arctic was in fact warmer in the 1930’s.