Above: Mt Erebus, Antarctica
picture by Sean Brocklesby
A press release today by the University of Washington makes a claim that Antarctica is warming and has been for the last 50 years:
“The study found that warming in West Antarctica exceeded one-tenth of a degree Celsius per decade for the last 50 years and more than offset the cooling in East Antarctica.”
…
“The researchers devised a statistical technique that uses data from satellites and from Antarctic weather stations to make a new estimate of temperature trends.”
…
“People were calculating with their heads instead of actually doing the math,” Steig said. “What we did is interpolate carefully instead of just using the back of an envelope. While other interpolations had been done previously, no one had really taken advantage of the satellite data, which provide crucial information about spatial patterns of temperature change.”
Satellites calculate the surface temperature by measuring the intensity of infrared light radiated by the snowpack, and they have the advantage of covering the entire continent. However, they have only been in operation for 25 years. On the other hand, a number of Antarctic weather stations have been in place since 1957, the International Geophysical Year, but virtually all of them are within a short distance of the coast and so provide no direct information about conditions in the continent’s interior.
The scientists found temperature measurements from weather stations corresponded closely with satellite data for overlapping time periods. That allowed them to use the satellite data as a guide to deduce temperatures in areas of the continent without weather stations.
…
Co-authors of the paper are David Schneider of the National Center for Atmospheric Research in Boulder, Colo., a former student of Steig’s; Scott Rutherford of Roger Williams University in Bristol, R.I.; Michael Mann of Pennsylvania State University; Josefino Comiso of NASA’s Goddard Space Flight Center in Greenbelt, Md.; and Drew Shindell of NASA’s Goddard Institute for Space Studies in New York City. The work was supported by grants from the National Science Foundation.
Anytime Michael Mann gets involved in a paper and something is “deduced” it makes me wary of the veracity of the methodology. Why? Mann can’t even correct simple faults like latitude-longitude errors in data used in previous papers he’s written.
But that’s not the focus of the moment. In that press release they cite NASA satellite imagery. Let’s take a look at how the imagery has changed in 5 years.
NASA’s viewpoint – 2004
Click for larger image
NASA’s Viewpoint 2007 (added 1/22)
NASA’s viewpoint – 2009
Earth’s viewpoint – map of Antarctic volcanoes
From the UW paper again:
“West Antarctica is a very different place than East Antarctica, and there is a physical barrier, the Transantarctic Mountains, that separates the two,” said Steig, lead author of a paper documenting the warming published in the Jan. 22 edition of Nature.
But no, it just couldn’t possibly have anything at all to do with the fact that the entire western side of the Antarctic continent and peninsula is dotted with volcanoes. Recent discovery of new volcanic activity isn’t mentioned in the paper at all.
From January 2008, the first evidence of a volcanic eruption from beneath Antarctica’s ice sheet has been discovered by members of the British Antarctic Survey.
The volcano on the West Antarctic Ice Sheet began erupting some 2,000 years ago and remains active to this day. Using airborne ice-sounding radar, scientists discovered a layer of ash produced by a ’subglacial’ volcano. It extends across an area larger than Wales. The volcano is located beneath the West Antarctic ice sheet in the Hudson Mountains at latitude 74.6°South, longitude 97°West.
UPDATE 1/22
In response to questions and challenges in comments, I’ve added imagery above and have a desire to further explain why this paper is problematic in my view.
The author of the paper himself (Steig) mentions the subglacial heat source in a response from “tallbloke” in comments. My issue is that they don’t even consider or investigate the possibility. Science is about testing and if possible, excluding all potential candidates that challenge your hypothesis, and given the geographic correlation between their output map and the volcanic map, it seems a reasonable theory to investigate. They didn’t.
But let’s put the volcanoes aside for a moment. Let’s look at the data error band. The UAH trend for Antarctica since 1978 is -0.77 degrees/century.
In a 2007 press release on Antarctica, NASA’s describes their measurement error at 2-3 degrees, making Steig’s conclusion of .25 degrees Celsius over 25 years statistically meaningless.
“Instead, the team checked the satellite records against ground-based weather station data to inter-calibrate them and make the 26-year satellite record. The scientists estimate the level of uncertainty in the measurements is between 2-3 degrees Celsius.”
That is from this 2007 NASA press release, third paragraph.
http://earthobservatory.nasa.gov/IOTD/view.php?id=8239
Also in that PR, NASA shows yet another satellite derived depiction which differs from the ones above. I’ve added it.
Saying you have a .25 deviation over 25 years (based on one-tenth of a degree Celsius per decade per Steig) with a previously established measurement uncertainty of 2-3 degrees means that the “deduced” value Steig obtained is not greater than the error bands previously cited on 2007, which would render it statistically meaningless.
In an AP story Kenneth Trenberth has the quote of the day:
http://news.yahoo.com/s/ap/20090121/ap_on_sc/sci_antarctica
“This looks like a pretty good analysis, but I have to say I remain somewhat skeptical,” Kevin Trenberth, climate analysis chief at the National Center for Atmospheric Research, said in an e-mail. “It is hard to make data where none exist.”
Hmmm…Well that sounds a lot like denying the evidence that goes against your pre-conceptions. I admit that more work needs to be done, and is being done, to understand and improve the proxy data…but to simply dismiss it out-of-hand is kind of ridiculous.
It’s a science vs. history kind of thing. Two different standards of proof. We do not require scientific proof that, say, George Washington, or Julius Caesar existed. Indeed, I would say it would be near impossible for science to prove it. But do you doubt it? And just about everywhere where they were capable of writing about it, the MWP existed. Is it therefore reasonable to presume that everywhere where there was no writing the MWP did not exist?
There’s an old saw told about Cordell Hull. He was traveling on a train with some colleagues and they looked out the window and saw a flock of sheep going by. Someone remarked, “Those sheep are shorn”. Hull is said to have replied, “At least on one side.”
Likewise, historical literature tells us there was an MWP. At least in one hemisphere . . .
So now the claim is that a third of the world stayed significantly warmer than the other two-thirds, for several hundred years.
What happened next? Did someone invent the jet stream and the Second Law of Thermodynamics?
evanjones says:
Even if we took your claim here on the historical record to be true (which I don’t without some real evidence to back it up), that still wouldn’t address the issue of whether the warm periods were synchronous or asynchronous. Are you saying that all this different places said specifically that the half-century period between, say, 1150 and 1200 was warm?
I would like to see before and after GISSification graphs of the temperatures from the stations used in this study.
The problem is that GISS never starts with raw data. They use NOAA-adjusted data and “unadjust it” (how, we do not know), then they readjust it.
So to compare, we would need either the “rawified” mess that GISS redjusts, or else NOAA raw data. (I would make that ‘semi-raw”, as the TOBS adjustment is valid.)
I don’t know about GHCN, but the USHCN-1 20th-century trend is adjusted 0.3C warmer and USHCN-2 is worse.
But it’s much harder to get the details on USHCN-2–they learned the hard way with USHCN-1 that it is politically unwise to make public even the amount of each adjustment step.
which I don’t without some real evidence to back it up
See the Harvard-Smithsonian study from 2003. It covers evidence from both eastern and western hemispheres.
The Loehle corrected reconstructions provide a scientific basis (via proxy), but the archaeological and literary record is separate from that.
Joel, I think you are quibbling. That would have to be the most lukewarm expression of confidence you could imagine any committee putting their name to even with their arms twisted behind their backs. It is far, far from supporting your claim that there was no world-wide concurrent medieval warm period.
Yes, CO2Science is about advocacy. Frankly and much less honestly, so are Mann and his cohorts. That doesn’t alter the fact that CO2Science has accumulated clear evidence that the MWP certainly did exist as a significant world-wide event.
Has anyone actually read Steig’s paper? I haven’t, but I would gladly read the comments of somebody who has read the article and can cogently and free from emotional rants critique Steig’s methodology. Any volunteers?
Re Michael Mann, the hockey stick and dendochronology:
Google the “Divergence Problem” to see how very unreliable tree rings are as a measure of temperature. Tree rings do not reflect the warming that occurred from ~1977 to ~1998 – they show cooling. So how can tree rings accurately assess the past?
http://www.climateaudit.org/?p=570
The discrepancy between the forecast and the actual caught Cuffey’s eye and he asked D’Arrigo about it. She said “Oh that’s the “Divergence Problem”. Cuffey wanted to know exactly how you could rely on tree ring proxies to register past warm periods if they weren’t picking up modern warmth “questions dear to the heart of any climateaudit reader. D’Arrigo explained that it had all been discussed by Briffa et al. I think that D’Arrigo said that the “divergence problem” only applied to a few sites.
I’ve discussed Briffa’s approch to the “Divergence Problem” before – see for example here – and we modified our presentation to respond to concerns about the “Divergence Problem”. First, we showed the following graphic, reporting that the “Divergence Problem” was not limited to a few sites, but applied to an entire network of 387 sites selected to be temperature-sensitive…
Domingo, it’s early days yet for proper analysis. In the meantime you could read Pielke Sr’s comments on Climate Science:
http://climatesci.org/2009/01/21/follow-up-on-todays-ap-article-by-seth-bornenstein-entitled-study-antarctica-joins-rest-of-globe-in-warming/
George E. Smith (18:16:06)
George, your post is a bit rantish! These issues can only be properly addressed with reference to what we know of the natural world from the science. I’m only going to address one of your points (your “set piece” rant against Gore’s ice core/CO2 correlation). You start this with:
Well fine, except what you say isn’t really true. I think we all know that Gore’s description was lacking in detail and could certainly have been described with more rigour. But we don’t need to stop at that point and “wheel out” the “Gore rant” whenever CO2 is brought into the conversation! We’d like to know what the science shows.
Here’s what Gore might say nowadays:
1. The atmospheric CO2 and temperature data in Gore’s presentation was from Antarctic ice cores, and these show that there is a lag (~800 +/- 200 or so years) between the onset of temperature rise and rising CO2.
2. While the CO2 rise lags the temperature rise in Antarctica during deglaciations, it likely leads the temperature rise in the tropics and certainly in Greenland; e.g. :
Caillon, N et al. (2003) Timing of atmospheric CO2 and Antarctic temperature changes across termination III. Science 299, 1728-1731
L. Stott et al. (2007) Southern Hemisphere and Deep-Sea Warming Led Deglacial Atmospheric CO2 Rise and Tropical Warming. Science 318, 435 – 438.
3. And very detailed analysis of cores is yielding more precise timing of temperature and greenhouse gas relationships between the polar regions.
EPICA community (2006) One-to-one coupling of glacial climate variability in Greenland and Antarctica. Nature 444, 195-198.
4. Al of these data are increasingly consistent with the conclusion that Milankovitch cycles that result in achingly slow variation of insolation patterns that drive ice age cycles (increased Spring insolation in the deep Southern hemisphere drives the glacial to interglacial transition) result in slow warming of the deep South which (with a lag) results in the onset of release of CO2 from the Southern oceans, and that the CO2 amplifies the warming, leading to delayed warming of the high Northern hemisphere as indicated in the temporal relationship between warming in Greenland cores and CO2 (warming in Greenland follows rising CO2).
Smokey (20:17:32) :
Sarcasm is fun but it doesn’ t really address the science!
Since the natural world is subject to radiative forcings and these have time-dependent amplitude variations, the Earth’s surface temperature distribution is always in a out-of-equilibrium state with rather complex temperature distributions and temperature gradients that vary temporally too. Just like our bodies, which are also maintained in an out-of-equilibrium during the course of our cheeky lives, these phenomena don’t disobey the 2nd Law of Thermodynamics.
Obviously it’s entirely possible for a redistribution of thermal energy (aka “heat”/”temperature”) to occur for all sorts of reasons. A good example that is pertinent to the Medieval Warm Period (MWP) and Little Ice Age (LIA) is the transport of heat to the high Northern latitudes by ocean currents (the Gulf Stream).
Thus there is evidence that during the Little Ice Age a reduced Gulf Stream flow reduced heat transport to the North Atlantic:
DC Lund et al. (2006) Gulf Stream density structure and transport during the past millenium. Nature 444, 601-604.
Of course there’s stronger evidence that solar effects and volcanic contributions were the main forcings for reduced temperatures during this period. However, changes in heat transfer by ocean currents provides a means by which the rather puny changes in solar irradiance might have been amplified in the high Northern latitudes. In a similar vein, the paleoevidence that the MWP was largely “focussed” in the Northern latitudes may well be understandable in relation to variations in heat transfer from the equator by the Gulf stream.
In other words regional and long lived changes in temperature may occur without very much <global warming. There’s evidence too that the tropical Pacific was in a cold La Nina-like state during the MWP (warm in the North, cooler in the South) and in a El Nino-like state during the LIA (warmer in the South, cool in the North). That’s what the paleodata tend to indicate:
Osborn TJ and Briffa KR (2006) The spatial extent of twentieth-century warming in the context of the past 1200 years. Science 311, 841-844.M/i>
And there’s very good evidence for a North-South “see-saw” from the analysis of timings of warm-cold proxies in ice-cores:
EPICA community (2006) One-to-one coupling of glacial climate variability in Greenland and Antarctica. Nature 444, 195-198.
So it’s certainly not unreasonable to consider that the MWP was somewhat localized in the highern Northern latitudes as a result of small redistributions of heat/changes in the Gulf Stream intensity and so on. Since that’s what the data indicate we should certainly not poo-poo the possibility!
Joel Shore (18:47:37) :
Here’s a quote from a 1998 paper by Spencer and Christy ( http://ams.allenpress.com/archive/1520-0442/11/8/pdf/i1520-0442-11-8-2016.pdf ) that gives us another couple of data points for my chart of how their trend has changed with time:
The combination of these changes causes the 18+ year trend of T2LT to be warmer by +0.03C / decade (-0.076 to -0.046 C /decade for January 1979–April 1997). We estimate the precision of the overall trend as +/- .05 C / decade.
So, in other words, before this 1998 paper their trend was -0.076 C / decade and after it, it was -0.046 C / decade.
And, note that their Aug. 2005 estimate of +0.123 C / decade lies well outside the +/- 0.05 C / decade error bars on that -0.046 C number (which, as per this paper has already been corrected at least once). [And, while some of this change could be due to the longer data series, from what I recall by some investigation of looking at the trends in their current data set out to various end-dates, I don’t think that much of it is. It would be easy enough to check this by computing the trend on their current data series restricted to that Jan 1979 – April 1997 time frame.]
************************************** [end of quote from Joel]
Sorry Joel,
You are wrong – virtually all of this effect is due to the longer data series.
From begin 1979 to mid-1997 there was essentially no warming in the LT, IF one chooses to measure warming by a linear best-fit to the global average LT anomaly.
In 1997-1998 there was the huge El Nino spike, that fell back to zero anomaly by mid 1999.
The only significant warming seen in the global average LT anomaly occurred from ~2001, followed by rapid cooling since January 2007.
Recently global average LT has bounced +/- 0.2 C around the zero anomaly.
Source of UAH LT data
http://www.atmos.uah.edu/data/msu/t2lt/tltglhmam_5.2
Linear trend begin 1979 to mid 1997 +0.0030C/year = +0.030C/decade
Linear trend begin 1979 to end 2008 +0.0127C/year = +0.127C/decade
Linear trend mid 1997 to end 2008 -0.0031C/year = -0.031C/decade
Using linear trends to measure segments of a naturally cyclical global temperature is not the best way to examine the data – better to just plot and examine it, or fit a polynomial.
If you want to predict future global temperature, throw out your linear best-fits, models and tree rings, as these are a waste of effort.
Instead, examine better proxies of climate history and natural cycles such as the PDO.
Smokey,
You say:
Your claim here seems to be that Mann hid the fact that his results depended strongly on a certain proxy (bristlecone pines from the Western U.S.). And, yet, here is what Mann et al. said in their 1999 paper (entitled, as foinavon has noted, “Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties, and Limitations”):
If you want to hide something, publishing it in Geophysical Research Letters is usually not the best strategy!
You say:
At any rate, I am not asking you to believe Michael Mann; I’m asking you to believe reputable sources like the NAS report rather than the politicized sources that your prefer.
Actually, what he said was that the computer code itself was his intellectual property, a claim that the agency that was funding him, the National Science Foundation strongly agreed with in a letter to Steve McIntyre (from http://www.realclimate.org/Mann_response_to_Barton.pdf ):
Nonetheless, Mann did eventually decide to release his computer code and, in their most recent work, they put the code and data up on a website simultaneously with the publication of the paper…a practice that, at least in the areas of physics that I have worked in, is almost unheard of. And, it is interesting to note that the one paper that McIntyre has actually published on the Mann work in a real peer-reviewed journal was prior to when Mann released his computer code … And, that other researchers were able to replicate Mann’s work prior to this release.
Actually, the National Academy of Sciences report that I linked to dealt with this claim directly:
(The report then goes on to note something that Mann et al. had essentially noted in their 1999 paper, which is that their reconstruction does strongly depend on that one particular data set from the southwestern U.S. I believe that addressing this deficiency has been at least one subject of other work, such as that of Osburn and Briffa and the latest Mann et al. work.)
First of all, the Wegman report was a report commissioned by the majority political party on the Congressional committee. Wegman and very narrow charge that he was given were no doubt chosen to obtain the result that they wanted. This whole witchhunt by the Barton’s committee was so repugnant that his fellow Republican Sherwood Boehlert, Chair of the House Science Committee, couldn’t stomach it and sent Barton a letter that you can read here: http://sciencepolicy.colorado.edu/prometheus/archives/climate_change/000497letter_from_boehlert.html
Second of all, given the narrow charge (and the statistics background of Wegman and the fellow committee members that he chose), the only scientific issue that Wegman could comment on the issue regarding the technique that Mann et al. used in their original paper, not on the broader issues, e.g., of what subsequent work done without Mann’s method showed. And, their conclusion that the method was problematic is not any different than what the NAS report concluded, but that report put things in a broader perspective. Mann et al. were pioneers in their field and it would not be the first time in science that the techniques used in the first paper of its kind in a field to obtain the results would be found to be problematic while at least the basic conclusions are verified by subsequent work. Spencer and Christy were pioneers in the satellite work…And, as foinavon and I have documented in this thread, not only were severe problems found with their techniques but it turned out that these problems significantly altered the conclusions. Yet, they have not been called “frauds” and hauled before Congressional committees and, in fact, in the skeptic community their more recent work, much of it with glaring errors, has been quite revered by that community.
Third of all, the overall bias of Wegman can be seen by the fact that, despite the fact that he is a statistician and not a climate scientist and, in fact, displayed quite a bit of ignorance of some basic facts of climate science when he appeared before Congress, he still apparently felt qualified about a year after his report to sign on to a letter to the Canadian Prime Minister that challenged the basic conclusions of scientists on climate change.
The question is not whether the MWP exists or not but how global a phenomenon it was and how its warmth compares to the late 20th centure warmth. Who exactly are these “mainstream climate scientists” who you speak of?
No, the question it comes down to whether you going to believe a group of people who have engaged in character assassination on a scientist or whether you are going to believe the views of the scientific community as expressed in the NAS and the latest IPCC report.
evanjones says:
By the Harvard-Smithsonian study, I assume you mean the one by Soon and Baliunas? When that study was published in a relatively small science journal, many of the editors (including the one who was going to become editor in chief) were so embarrassed by the fact that such a poor piece of work, whose conclusions apparently didn’t even follow from their data, was published that they quit. And, even the publisher admitted that the editorial review had failed in the case of that particular paper. (I.e., the only disagreement between the publisher and the editors that quit was in regard to whether the editorial process in that journal was generally problematic…or whether it just failed in that one case.)
As for Loehle, that was a study published in the journal Energy and Environment, which is not considered a serious peer-reviewed journal, received by only a handful of libraries around the world. (There used to be a good article about Energy and Environment available, I believe, from the American Chemical Society’s newsletter “Chemical and Engineering News” but alas they seem to have taken it offline…Or at least no longer freely available if you are not a member.)
Here is a discussion of some of the problems with that paper: http://www.realclimate.org/index.php/archives/2007/12/past-reconstructions/
John M (18:53:58) :
Although you don’t give any insight into your stance you seem to have a problem with the scientific literature. Some of the discussion on this thread highlights exactly why it’s vital for a dispassionate assessment of scientific issues.
The science indicates that since Mann et al’s 1998/9 paleoproxy analysis, the intervening years have seen around 10 subsequent paleoproxy analyses, that these are largely in accord with the original paleoproxy data, that a very detailed series of analyses demonstrates that the essential features of the original analyses are robust and internally consistent, that there are now over 1200 useful paleoproxy series and that these continue to grow and inform our understanding, that the paleoproxydata can be assessed without recourse to tree ring data and so on…
[snip, you are creating an image and label that is not acceptable. nor mentioned in this thread, stop it. – Anthony]
It really depends on whether one wants to understand the science on these issues (in which case look at the scientific literature), or to pursue an agenda(or some one else’s agenda, more likely).
Allen M R MacRae says:
You clearly missed my later post when I noted that a significant amount of it is due to the longer series. However, “virtually all” is demonstrably incorrect. Their pre-1998 analysis method gave a trend of -0.076 C / decade for the Jan 1979 – Apr 1997 data (as per their 1998 paper that I lined to); their current analysis gives +0.029 C / decade for that same data (a number that you have verified to 0.001 in your post). That is a change in trend of +0.105 C / decade due solely to changes in their analysis.
Since the trend for the full data set we now have through Dec 2008 is +0.127 C / decade, the change due to the longer time series is +0.098 C / decade.
Thus, counter to your claim, a tiny bit over half of the change in trend is due to changes in the analysis, not the longer data series.
Allen M R MacRae says:
Fitting to a polynomial is generally a horrible thing to do with noisy data. It results in overfitting, i.e., just fitting to the noise. That is easily verified if you actually make a computation of the errorbars in the parameters that you determine from your fit. In fact, with the 30 years of temperature data that we have, the only sort of fit that can be supported is a linear fit, even then, the error bars are still not that small…But the data is good enough to show that the linear trend has statistical significance.
Joel Shore (08:04:04) :
Allen M R MacRae says:
Using linear trends to measure segments of a naturally cyclical global temperature is not the best way to examine the data – better to just plot and examine it, or fit a polynomial.
Fitting to a polynomial is generally a horrible thing to do with noisy data. It results in overfitting, i.e., just fitting to the noise. That is easily verified if you actually make a computation of the errorbars in the parameters that you determine from your fit. In fact, with the 30 years of temperature data that we have, the only sort of fit that can be supported is a linear fit, even then, the error bars are still not that small…But the data is good enough to show that the linear trend has statistical significance.
**********************
Joel,
If your belief is that warming is linear and can be extrapolated, then use a linear fit. However, there is no evidence to support such a belief.
There is overwhelming evidence that climate is cyclical and natural – global temperatures have been warmer and cooler in the past than today.
The Mann hockey stick was completely discredited by Wegman’s non-partisan committee.
Modelers has shown no skill in prediction of global temperatures. Even hind-casting (history-matching) of models has required contortions such as invention of aerosol data.
Now, Earth has probably entered a cooling trend consistent with a negative PDO – time will tell…
Where is your evidence that we face a global warming crisis?
I suggest that such evidence does not exist.
Regards, Allan
Over ClimateAudit, Ron Cram asks:
Creationists believe in teleology while the team believes in teleconnection.
Allan M R MacRae says:
The issue is not whether one believes it is perfectly linear. The issue is one of not overfitting to data. All that we are able to do with the 30 years of satellite data is to look at the linear trend. That doesn’t mean the underlying warming is exactly linear but it simply gives us the first term in the series…and the only term we have any ability to compute with any sort of precision.
The House committee that appointed Wegman to write that report was so partisan that even fellow Republican Sherwood Boehlert, Chair of the House Science Committee, condemned their actions. And, Wegman looked at only a very narrow issue that everyone now agrees on…namely, that the particular way in which Mann et al. implemented their principle components analysis is not the recommended way to do it and one can manufacture datasets where it leads to spurious conclusions. Yes, Mann wasn’t perfect. But, the peer-reviewed work since then (including work using the same data but not doing the analysis that way) has largely confirmed his basic results. (There are some differences in regards to how “flat” the handle of the stick is but the different reconstructions generally show the late 20th century warmer than any time during the MWP…See here: http://en.wikipedia.org/wiki/File:1000_Year_Temperature_Comparison.png )
At any rate, the work on temperature reconstructions of the last millenium or so is only one piece of evidence…and the most circumstantial at that…in the argument for AGW.
Indeed it will. This is actually just the latest desperate hypothesis from those who want to ignore all the evidence going the other way.
Read the IPCC report. You are now taking this discussion far afield from where we started, presumably to distract from the fact that your claim that the corrections to the UAH data set were not significant has been shown to be utterly false.
foinavon (07:37:04) :
I accept the scientific literature for what it is: a flawed but perhaps best effort at communicating imperfect data. I do not view it with the reverance associated with stone tablets carried down from the mount.
I was responding to your apparent opinion that number of publications is what matters, which you have now repeated. It reminds me (sorry if you don’t like my rambling, but tuff) of a supposed statement by a young assistant professor referring to his latest work as he was seeking tenure: “This one’s for people who can count but can’t read.”
This peculiar area of paleoclimate reconstructions does not depend on the number of papers by “independent” researchers, but rather on whether the data treatment is correct. Most journals do not consider ongoing discussions about “data treatment” to be novel enough for publication, hence counting published papers may give a misleading representation. Also, critics tend not to have armies of post-docs and grad students, not to mention university and institutional staff to carry the water.
You are free to disagree, and you are free to continue to only value peer reviewed publications, but in my own experience, I don’t usually recognize the flaws or unanswered questions in published papers until I need to sit down and spend hours on one deep drilling every figure, table, and experimental procedure. Whether or not the paper is insightful or correct doesn’t depend on whether I can publish a rebuttal, but rather on whether the paper stands up to close, critical, evaluation.
The Steve McIntyre’s of the world are doing a service by providing a much more thorough vetting of published works than the refereeing process is capbable of. McIntyre has provided his analysis of most or all of the supporting information you cite. He has argued that the data are not independent or that there are other issues with the other proxies.
Perhaps you ought to confront him directly?
Allen: By the way, this statement you made deserves a little more comment:
First of all, while I agree with your trends for 1979-1997 and 1779-2008, I think you have made in error in the last trend (1997 – 2008). When I look at Apr 1997 to Dec 2008, I get a trend of + 0.004 C / decade. (I chose April to start here because that matches the two segments together so you are including the whole data range.)
Second of all, your statement that looking at segments is not a proper way to do things is an understatement. For one thing, the error bars on the trends over the segments will be considerably larger than for the trend over the entire record…so they might say very little about what the underlying trends actually are.
However, there is another even more severe and more subtle problem with the way you have done this here. It can be illustrated by the following paradox: If you consider two line segments representing the two linear fits of the two time periods and assume they join in Apr 1997, and then you consider a line connecting the two endpoints (Jan. 1979 and Dec 2008), it is clear that this longer line must have a slope intermediate between the slope of the two segments. However, if you look at the trends computed for Jan. 1979 – Apr 1997, Apr 1997 – Dec 2008, and Jan 1979 – Dec 2008, you will see that both of the trends for the shorter periods are smaller than the trend over the long period! How can this be the case?
The answer came to me after a little bit of thought: There is no guarantee that the linear fits over the two time periods (Jan 1979 – Apr 1997 and Apr 1997 – Dec 2008) actually meet in Apr 1997. And, in fact, in this case, they must not even come particularly close, with the line for the 1997-2008 period lying well above the line for the 1979-1997 period in Apr 1997. Fitting a trend over a longer period by two line segments determined from the trend over the shorter periods that you do not require to even have the same value at the meeting point of the data is, along with an opportune choose of where you break the data, a good way to make the trend over the longer period appear to substantially disappear (or, if you chose to break the data at another point, you could perhaps cause the trend to be exaggerated).
This is indeed a very unwise way to analyse the data over the full time period…In fact, I would say that it is essentially meaningless!
We live in a republic that has walls. And those walls have to be guarded by men with thermometers. Who’s gonna do it? You? You, Dr Hansen? I have a greater responsibility than you can possibly fathom. You weep for those Polar Bears and you curse the temperature takers. You have that luxury. You have the luxury of not knowing what I know. My existence, while grotesque and incomprehensible to you, saves useless expenditure of national treasure and retards the genocidal effects of the policies you implement.
You don’t want the truth. Deep down, in places you don’t talk about when your are sleeping alone late at night after those Georgetown cocktail parties after chowing down on limp quiche and swilling a third rate California Chardonnay devoid of pretension, you want me on that wall you need me on that wall. We use words like Little Ice Age, Medieval Warming Period, and Toga Parties …we use these words as the backbone to a life devoted to taking temperature.
Joel,
For my earlier post on UAH global average LT linear trends:
Linear trend begin 1979 to mid 1997 +0.0030C/year = +0.030C/decade
Linear trend begin 1979 to end 2008 +0.0127C/year = +0.127C/decade
Linear trend mid 1997 to end 2008 -0.0031C/year = -0.031C/decade
I suggest that these trends are, indeed, insignificant and extrapolating them is foolish. The 30-year trend since the satellites were first launched is only half of a PDO cycle – and it is the WARMING half.
Examining the data back to the beginning of the full PDO cycle in the 1940’s shows no net warming since that time, is spite of an increase in humanmade CO2 emissions of almost 800%.
Appeals to authority such as the IPCC do not impress. Neither do attempts at obfuscation and personal attacks. Wegman was clearly non-partisan – the committee you refer to is not relevant.
You are talking malicious nonsense and I’ve had enough of you (and Fiona too).
Joel,
My last response referred to your post of (09:45:18) :
Your most recent post (10:06:46) appeared after I made my submission.
I will not comment on your latest post – I have already commented on the fallacy of taking short linear segments of cyclical data and extrapolating them.