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.”
Here’s a link to R&D magazine’s report on this. You can comment, so please do.. 🙂
http://abrd-media.com/portal/wts/ccmc7iaVq7aqrErqEzixcr8ijCj
From the first line of their publication (i.e. the title) it is clear that it was all for good AGW PR exercise.
I have serious doughts as to if really it is warming but one thing is certain, warm air picks up more moisture and increases precipitation in the area. That leads to a lowering of sea levels and not an increase.
This is from Google Earth. It is interesting how they give other logical explanations… other than AGW for the break down of the ice shelves!
“Scientists have observed the ice along the Antarctic Peninsula disappearing in a series of retreats over the past 30 years. The climate in this area is warming at approximately 0.5 degrees Celsius per year following a trend that is believed to have been occurring for at least the past 50 years (NASA, 2006). Generally this retreat has occurred as icebergs break away from the oceanward edge of the ice. More recently a new pattern has been observed.
Scientists have been closely monitoring the Larsen Ice Shelf since 1995 when a large portion of it (Larsen A) dramatically disintegrated. In 2002 another similar event occurred at Larsen B which is captured in this remarkable series of MODIS images. In contrast to the slower pattern of calving – where pieces of ice break away at the edge of the shelf – these two events occurred over a large area and in a relatively short period of time. In the case of Larsen B 3,250 square kilometers of the ice shelf shattered into a plume of 1000s of icebergs in a little over a month. Over the last 5 years approximately 40 per cent of Larsen B has disintegrated – 5,700 square kilometers. Larsen A is believed to have been in place for over 2000 years at the time of its collapse and Larsen B is thought to have been still older (Portland State University, 2002).
Scientists have developed theories to explain Larsen B’s catastrophic collapse, linking it to summertime warming and the pooling of melted water on the surface of the ice (Scambos et al., 2000) as well as differences in the rates of movements of the several glaciers feeding into the ice shelf (Glasser and Scambos, 2008). The pooling water is believed to accelerate the expansion of crevasses and lead to the breakdown of the ice shelves. In addition, the differences in the rates of flow from various glaciers are believed to have created structural weakness in the ice shelf (Glasser and Scambos, 2008). In the case of Larsen B, ponds of melt water can be seen in the remote sensing images taken shortly before the collapse occurs (January 2002 image), lending credence to this theory. Melt water ponds have been seen forming on Larsen C in more recent images, however there appears to be less of the structural weakening from glacier flow on Larsen C and this may make it less vulnerable to catastrophic collapse.”
Anthony et al,
When I read these stories in the press (like the New York Times, today, or the San Diego papers yesterday), I often wonder if any one of you skeptics out there actually contact the press articles and point them to WUWT or junkscience or McIntyre’s blog to have the mindless reporters read the opposing viewpoint on each and overy one of these papers with “new evidence” of climate change and global warming? We can blog all we want among ourselves as skeptics, but we need to ACTIVELY provide some retort and opposing view to educate the very-uninformed-press reporters, who often have little or no scientific training or experience. The only way to counter the IPCC, Al Gore and Hansen is to use the same techniques they do: i.e. press conferences, press releases, lobbying, open letters in the N.Y. Times, etc. We all sit here piling-on counter-evidence or skeptical dissent, but the real battle is winning over the media and the politicians, to stop the hype so I don’t get taxed for pouring a concrete driveway, burning wood in my fireplace or breathing to heavily. Again today, my governor (Arnold), in order to deflect the disaster here in California over the budget, deflected the financial crisis once again by mentioning he will lobby President Obama to consider giving the power back to the States on Carbon emissions limits to override the EPA’s regulations.
Old-Growth Forests Dying Off in U.S. West
I saw this in the Washington Post, you guessed it. Global warming is killing them and once they die, even more global warming will happen.
http://www.washingtonpost.com/wp-dyn/content/article/2009/01/22/AR2009012202203.html
[snip- sorry can’t allow this, even though humorous, it opens too many doors to similar use of language we generally don’t tolerate here]
Gary Plyler (11:49:02) :
Really? Since the numerous plaeoproxy temperature analyses of the last 10 years are essentially compatible with Manns 1998 study, one would surely conclude that the original rather tentative study has been reinforced by a very large amount of new analysis in the intervening years:
http://www.ncdc.noaa.gov/paleo/recons.html
Mann and coworkers have recently published a very extensive analysis comprising more than 1200 proxy series. Not a huge amount has changed other than that we’re rather more confident that late 20th century and current warming is anomalous in the context of the past 100-plus years.
M. E. Mann et al. (2008) Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia
Proc. Natl. Acad. Sci. 105:13252-13257
If the radiosonde data has well characterized spurious artefacts we’d be very silly indeed not to take these into account.
S. C. Sherwood et al. (2005) Radiosonde Daytime Biases and Late-20th Century Warming Science 309, 1556 – 1559.
We’re not really expecting that much Antarctic warming yet (see my post 11.54.32). The fact that there might be some warming in the (non-peninsular) vast regions of Antarctica is interesting and useful to know.
More science, happily! We certainly want to find out as well as we can what’s occurring in response to extraordinary enhancement of the atmospheric greenhouse gas concentrations.
whoops! two typos:
foinavon (12:34:29)
“Steitz” should read “Seitz”
foinavon (13:31:48)
“anomalous in the context of the past 100-plus years” should read anomalous in the context of the past 1000-plus years”
An Inquirer (07:26:50) : Steig explains that they established a relationship between two sets of variables in the last twenty five years and then based on that relationship estimated temperatures in areas of the continent without weather stations for the previous 25 years. That is extrapolation which is more prone to error than interpolation.
And even easier to pollute. OK, so they have (biased IMHO) GISS and now they can give the same ‘lift’ to 25 years worth of satellite data via extrapolation of the ‘relationship’… Nicely done.
Mann gets to say “See my technique is sound” since the ‘cheat’ is in the GISS data, others get to wring their hands over the ‘proven’ warming and apply for grants, Hansen gets to say GISS is the best around, the satellite folks get to claim they are Of The Body and contributing to The Canon of Received Science now. Everybody wins. And you can not detect the ‘fraud’ unless you deconstruct the GISS data manipulation, which they won’t let you do.
More and more this all looks to hinge on what GISS is doing to the raw data to turn it into pasteurized processed data food product…
(For those not in the USA: Cheese here comes in many strange and wondrous types. Real cheese is labeled ‘cheese’. As it gets adulterated with more and more non-cheese, additional qualifiers are added. The ‘bottom rung’ may be stored near cheese, but the actual relationship to cows and milk was lost long ago. That is “pasteurized processed cheese food product” and sometimes comes in aerosol cans, at others as slices that don’t melt when cooked on a burger…)
“” foinavon (11:54:32) :
George E. Smith (10:45:01) :
Conventional wisdom suggests that the polar regions are supposed to warm at a FASTER rate than the planet as a whole.
and:
So bottom line is, if GHG effects based on CO2 are warming the planet, and for other reasons, the polar regions ought to warm FASTER that the rest of the earth.
That may be “conventional wisdom” but it’s not what the science has shown! It’s been known for 25 years that the expectation for polar warming in response to an enhanced greenhouse effect due to raised greenhouse gas concentrations, is for a strong warming in the high Northern latitudes with a reduced/delayed warming in the deep Southern latitudes particularly in Antarctica. “”
Well when I said “Conventional wisdom”, I was referring to what the general public have beed told constantly via the lay media..
As to why the northern hemisphere should warm faster than the southern; that does not compute in my book.
Since the southern hemisphere is mostly oceans, which have almost total black body absorption for solar eenergy (maybe 97%), then the southern hemisphere wouldn’t contribute very much to the earth albedo, compared to what the Northern hemisphere contributes. also earth is further from sun during Antarctic winter, hence closer to sun during southern hemisphere summer; so total irradiance of the southern hemisphere is greater than for northern hemisphere.
All the land area in the northern hemisphere contibutes a much higher albedo component, than does the black southern hemisphere oceans, and with all that higher elevation land in the north, I would venture that there is more cloud cover in the northern hemisphere than in the southern, further increasing the albedo bias towards the northern hemisphere.
So I would say it is a slam dunk, that the southern hemisphere collects more solar energy than the northern hemisphere.
And since the surface temperatures of the land can get much higher than the surface temperatures of the ocean, then the radiative cooling of the northern hemisphere, is much greater than the radiative cooling of the southern hemisphere.
Well if you measure “warming” solely in terms of temperature; then oyu would favor the northern hemisphere; but if you measure warming in terms of retained energy from the sun, then that would favor the southern hemisphere.
If you put out two objects in the sun, and one has a much higher “heat capacity than the other then the one with the lower heat capacity will reach the higher temperature, but it won’t contain as much thermal energy as the other one.
George
Disclaimer, I have not read the comments above, but I did read this yesterday on Science Daily. Lets be clear “interpolate carefully” means that they made certain assumptions, possibly linear between points or perhaps they assumed some kind of non-linear realtionship. In my business we interpolate crap all the time. You’re a damn fool if you assign it more value than it deserves. Apparently, if you read the fine print, they have assigned statistical probabilities which, lo and behold, still allow that the bulk of the continent might have cooled.
No new data here, it’s just been massaged to get a headline.
“Simon:
I’m rather puzzled as to why some here did not make the same point when previous analyses have suggested Antarctic cooling? It does seem to me that the accuracy of measurements, whether surface-based or satellite, only comes into question here when they are suggestive of warming.”
I have a different opinion. I believe that what gets questioned here is poor science, not just accuracy of measurements.
“Hmm, well there’s long history here of people objecting to efforts that have been made to take account of, and adjust for, observational inadequacies,…”
Again, I beg to differ. The objection to those efforts have centered on the fact that the adjustors refuse to release the means of the adjustment so that the means/methods can be understood, challenged, authenticated, or tossed.
Certainly you know this…so I don’t understand the swipe? Do you not believe that the work of publicly funded scientists should be released to the public?…or that other scientists should be given the opportunity to analyze methods and attempt to reproduce/recreate results of various experiments as a point of validation?
JimB
Per ‘the volcano did it’, will Harvard and NASA do?
http://adsabs.harvard.edu/abs/2003ESASP.535..393S
States that there is a well demonstrated correlation of more volcanism with solar minima and less with solar maxima. Given that there are volcanos under the ice down there, the heat output ought to cycle somewhat with solar periods of longer duration. Did the Mann paper allow for that?
I think there is at least a plausible confounder of their western heating by CO2 thesis…
Oh, and notice as we enter this Modern Minimum volcanos are starting to light up all over the place? I have a chart somewhere I can’t find right now that shows a significant ramp up in volcanism lately world wide. I doubt that the Antarctic would be immune…
Now if only there was a reasonable way to connect volcanism, crustal deformation, sunspot minima, earthquakes, et. al. without resorting to planetary orbit-spin coupling and solar barycentric orbits …
Hmmm, some possible warming in West Antarctic with volcanic ash (not usually as high an albedo as snow/ice) being produced just to the west (also known as upwind).
Maybe, just maybe, there is a reason that only West Antarctic is exhibiting some of the same behavior as the Arctic…they actually do have something in common. A source of non-white aerosols.
Stephen Hill, just wanted to add that Andrew Weaver is a climate modeler and has refused to debate the subject in an open forum.
NPR has their take up now:
http://www.npr.org/templates/story/story.php?storyId=99681830&ps=bb4
Some excerpts:
“It’s like having data in San Francisco and New York and trying to say something about Arizona,” says Steig. “You really need some more information if you’re going to say anything reasonable about Arizona.”
…
“Temperatures have risen by about 1 degree near the equator to more than 5 degrees near the North Pole.
‘It’s much less than Arctic warming but it pretty much is on par with global average warming,’ Steig says.”
…
“Re-Assuring Discovery
Previous studies have not found a warming trend in Antarctica. Steig’s conclusion is therefore a shift, but it’s not a total surprise.
“This one study should not cause anyone to suddenly get more worried. If they are taking it seriously already, then this should not make them change their view particularly,” he says.
In fact, Arctic scientist Richard Alley at Penn State University says he finds the new information reassuring — in a way.
“The world looks a little more sensible to me than it did before,” he says.”
My favorite bit of alarmism:
“…the coastlines of the world would be obliterated if Antarctic ice melted away and raised global sea level.”
The coastlines of the world are, of course, obliterated every day by the tides.
The MSUlt data is pure fiction over the Antarctic. The surface ice sits far above the peak in the weighting function.
Oh, you mean these “independent” studies?: http://www.climateaudit.org/?p=4866
foinavon (12:06:17) :
John Galt (10:57:12) :
Why don’t people like Mann and Hansen attend and debate the issues publicly? I’m sure that since the science is clearly on their side, they’ll have no trouble persuading the deniers to get on board before it’s too late.
Unfortunately that tends to be a particularly fruitless and unsatisfactory activity. Far better for scientists to publish their work in the scientific literature, attend scientific meetings and engage directly with other scientists and policymakers. These requests for “debate” tend to politicise/factionalise what are scientific issues…
I’m not asking them to debate me, but to engage their peers who are skeptical of AGW. Public debate with (or between) laymen might be entertaining but it rarely solves anything. Just look at some of the internet sites where people can post their views. Nobody ever seems to be open-minded enough to really consider the other side’s arguments.
What I would really like all the climate modelers to do is release their input data and their source code for everybody to see. Hansen is a public servant. GISS is support by my tax dollars and short of national security issues, everything should be available to the public.
Do you suppose I could sue under the FOIA to get a full release of all of GISS notes, their inputs, the adjusts and the source code used to create their models?
Ray,
Here is another excerpt from the NPR antarcticle for you:
“Forecast: More Snow
Up to a point, Antarctic warming can actually reduce sea level. Warming there can take water out of the ocean and deposit it on the continent, in the form of increased snowfall.
‘West Antarctica should be getting more precipitation along with this increased temperature. But I think the data to demonstrate that are not really available,’ Steig says.
In fact, the best data from Antarctica show that the continent is putting slightly more water into the ocean than it’s taking out.”
Bob Tisdale (02:53:41) :
Anthony: I’m going to try to post on the Antarctic TLT sometime today or tomorrow as part of the series I was doing on the effects of ENSO and volcanic eruptions on TLT. Here are a few preview graphs of Antarctic temperatures from that future post.
I wouldn’t waste your time, MSU isn’t useful over Antarctica.
The following are graphs of Antarctic and Southern Ocean TLT [AHU MSU] created from data available through the KNMI Climate Explorer Website. Keep in mind that the MSU satellite data does not reach the entire Antarctic, which is something I found curious about the use of satellite data for the University of Washington study. (They must be supplementing the sparse surface measurements with it.) In fact, RSS only lists data as far South as 70S.
MSU is not the only satellite available, as clearly stated in the paper they used AVHRR to measure surface temperature!
http://wdc.dlr.de/sensors/avhrr3/
Neil Hampshire (00:45:54) :
Does this mean that the satellite data is now considered to be a valid measurement of global temperature trends or is it only valid in Antartica?
In this case mainly the latter, read the paper and you’ll find out why.
George E. Smith (13:54:37) :
really? I can’t say I’ve noticed! In any case we shouldn’t be listening to “conventional wisdom”…we should be following the science. And the science has long predicted (for 25 years or more) that the high Northern latitudes should warm earlier and faster than the deep Southern Circumpolar latitudes (see citations to early work on this issue in my post 11:54:32).
How else does one measure warming? Clearly the parameter of interest to our selves, our agricultural production, the terrestrial biosphere and so on, is the surface temperature. As has been predicted for 25 years or so, enhanced greenhouse warming should result in an earlier and larger surface warming of the high Northern latitudes compared to the deep southern (especially Circumpolar/Antarctic) latitudes (see citations in my post 11:54:32, for example).
As for “retained heat”, yes the expectation is that the greatest amount of thermal energy will be retained in the Southern Oceans. That’s essentially what the papers cited in my post above 11:54:32 state. As I said:
Foinavon 13.31.48
You linked to a long list of paleo proxies to support Dr Mann. Did you actually read them?
http://www.ncdc.noaa.gov/paleo/recons.html
“ABSTRACT:
The precisely dated isotopic composition of a stalagmite from Spannagel Cave
in the Central Alps is translated into a highly resolved record of temperature
at high elevation during the past 2000 yr. Temperature maxima during the
Medieval Warm Period between 800 and 1300 AD are in average about 1.7°C higher
than the minima in the Little Ice Age and similar to present-day values.
The high correlation of this record to d14C suggests that solar variability
was a major driver of climate in Central Europe”
Similar to present day values and the sun is the major driver. Thanks for this gold mine, I am still digging through it.
TonyB
Senator Inhofe’s site gathers together a lot of the material debunking this report at http://epw.senate.gov/public/index.cfm?FuseAction=Minority.Blogs&ContentRecord_id=fc7db6ad-802a-23ad-43d1-2651eb2297d6&Issue_id=
Of course, the media darlings have swarmed all over this in the hight of a SH Summer – perfect for photo ops of “melting ice”.
Deducing data? Result wiped by the margins of error? – just how will this result be tested? Where’s the science?
Scandalous.