Friday, January 23, 2009

New Antarctic `Warming' study is a guesstimate that defies the known facts

The whole thing is based on "estimates" and "reconstructions" of Antarctic temperatures, not on actual measurements! How surprising that the authors come up with "estimates" that confirm their well-known beliefs! Excerpts from one commentary below. See the original for links. First however, see below an amusing graph taken from the home page of one of the authors of the new "study". It is a graph of actual warming and shows -- wait for it -- that Antarctica COOLED. These crooks cannot even keep their own story straight! I'm saving a copy of the graph in case they delete it



A new study on Antarctic temperatures - which is contrary to the findings of multiple previous studies - claims "that since 1957, the annual temperature for the entire continent of Antarctica has warmed by about 1 degree Fahrenheit, but still is 50 degrees below zero."

Despite the fact that the study was immediately viewed with major skepticism by scientists who are not skeptical of anthropogenic global warming claims, many in the media pounced on the study as a chance to attack those skeptical of man-made climate doom. According to the release of the study, "The researchers devised a statistical technique that uses data from satellites and from Antarctic weather stations to make a new estimate of temperature trends. [.] 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." (emphasis added)

Few media outlets noted that in 2007 Antarctic "sea ice coverage has grown to record levels since satellite monitoring began in the 1979, according to peer-reviewed studies and scientists who study the area."

The new Antarctic study was published in Thursday's issue of the journal Nature and the lead author of the study was Eric Steig, a University of Washington professor of Earth and Space Sciences. Other co-authors include: David Schneider of the National Center for Atmospheric Research in Boulder, Colorado, a former student of Steig's; Scott Rutherford of Roger Williams University in Bristol, RI; and Michael Mann of Pennsylvania State University.

UN IPCC lead author, Dr. Kevin Trenberth, who is not in any way a climate change skeptic, said of the study, "I remain somewhat skeptical. It is hard to make data where none exist." Echoing Trenberth's analysis were several other scientists.

Climatologist Dr. John Christy of the University of Alabama in Huntsville questioned the study. "One must be very cautious with such results because they have no real way to be validated," Christy told the AP. "In other words, we will never know what the temperature was over the very large missing areas that this technique attempts to fill in so that it can be tested back through time," Christy added.

Former Colorado State Climatologist Dr. Roger Pielke, Sr., senior scientist at the University of Colorado in Boulder said the authors of the Antarctic study "overstated" their results. "In terms of the significance of their paper, it overstates what they have obtained from their analysis," Pielke told the AP. "In the abstract they write, for example, `West Antarctic warming exceeds 0.1C per decade over the past 50 years.' However, even a cursory view of Figure 2 shows that since the late 1990s, the region has been cooling in their analysis in this region. The paper would be more balanced if they presented this result, even if they cannot explain why," Pielke wrote. Pielke also questioned how the authors "reconcile the conclusions in their paper with the cooler than average long term sea surface temperature anomalies off of the coast of Antarctica." Pielke added, "These cool anomalies have been there for at least several years. This cool region is also undoubtedly related to the above average Antarctic sea ice areal coverage that has been monitored over recent years."

A critical analysis of the paper from December 21, 2008, accused the authors of the Antarctic study of making questionable data "adjustments." (See: Scientist adjusts data -- presto, Antarctic cooling disappears - December 21, 2008) The analysis concluded, "Looks like [study author] Steig 'got rid of' Antarctic cooling the same way [Michael] Mann got rid of medieval warming. Why not just look at the station data instead of 'adjusting' it (graph above)? It shows a 50-year cooling trend," the analysis concluded.

The BBC's Richard Black filed a report on the new study that included this claim: "'It's hard to think of any situation where increased greenhouse gases would not lead to warming in Antarctica,' said Drew Shindell from NASA's Goddard Institute for Space Studies (GISS) in New York." Sadly, Black of the BBC does not report that the promoters of man-made global warming fears had already concocted explanations for the failure of Antarctica to warm as models predicted.

The warming partisans at RealClimate.org have claimed that a cooling Antarctica is just what the models predict! "A cold Antarctica is just what calculations predict," stated a February 12, 2008, post on Real Climate titled "Antarctica is Cold? Yeah, We Knew That." The website claimed "Despite the recent announcement that the discharge from some Antarctic glaciers is accelerating, we often hear people remarking that parts of Antarctica are getting colder, and indeed the ice pack in the Southern Ocean around Antarctica has actually been getting bigger. Doesn't this contradict the calculations that greenhouse gases are warming the globe? Not at all, because a cold Antarctica is just what calculations predict. and have predicted for the past quarter century."

So which is it? Models predict Antarctic cooling or do they predict warming? If Antarctica is now allegedly warming, why didn't the models predict that? The spin [more like a cartwheel] by Michael Mann of RealClimate.org and the media on this study is stunning.

Real Climate's logic was mocked by Professor Roger Pielke, Jr., professor in the environmental studies program at the University of Colorado. "So a warming Antarctica and a cooling Antarctica are both `consistent with' model projections of global warming. Our foray into the tortured logic of 'consistent with' in climate science raises the perennial question, what observations of the climate system would be inconsistent with the model predictions?" Pielke Jr. wrote on January 21.

Some more reactions to the New Study

Michael "Hockey Stick" Mann Touts Study as a Way to Refute Skeptics. Excerpt: "Contrarians have sometime grabbed on to this idea that the entire continent of Antarctica is cooling, so how could we be talking about global warming," said study co-author Michael Mann, director of the Earth System Science Center at Penn State University and Real Climate contributor. "Now we can say: no, it's not true ... It is not bucking the trend." [Note: For a reality check on Michael Mann's failed attempt to resurrect the "Hockey Stick," see this report.]

Meteorologist Anthony Watts who runs WattsUpWithThat.com also questioned Mann's involvement in the study. "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," Watts wrote on January 21.

Even Pro-AGW scientists wary of this new study! Kevin Trenberth says `I remain somewhat skeptical. It is hard to make data where none exist.' Excerpt: The researchers used satellite data and mathematical formulas to fill in missing information. That made outside scientists queasy about making large conclusions with such sparse information. "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." Shindell said it was more comprehensive than past studies and jibed with computer models.

Alabama State Climatologist Dr. John Christy of the University of Alabama in Huntsville slams new Antarctic study for using "best estimate of the continents temperature" Excerpt: Technique questioned: Researchers in this study developed a new technique that combined data from satellites and automated weather stations in Antarctica to make what they say is the best estimate of the continent's temperature so far. However, there are very few weather stations on Antarctica, and the satellite data have been available for only the past 25 years. This troubles some scientists. "One must be very cautious with such results because they have no real way to be validated," says atmospheric scientist John Christy of the University of Alabama-Huntsville, who was not part of the study. "In other words, we will never know what the temperature was over the very large missing areas that this technique attempts to fill in so that it can be tested back through time." Researchers had thought Antarctica was getting cooler in part because of the ozone hole over the South Pole. This break in the protective ozone layer brings cooling weather patterns across parts of Antarctica. Steig agrees that the ozone hole has contributed to cooling in East Antarctica. "However, it seems to have been assumed that the ozone hole was affecting the entire continent, when there wasn't any evidence to support that idea, or even any theory to support it," he adds.

Pielke Sr. Challenges New Antarctic Study - January 21, 2009. By Former Colorado State Climatologist Dr. Roger Pielke, Sr., senior scientist at the University of Colorado in Boulder. Excerpt: 3. How do the authors reconcile the conclusions in their paper with the cooler than average long term sea surface temperature anomalies off of the coast of Antarctica? [see: http://www.osdpd.noaa.gov/PSB/EPS/SST/data/anomnight.1.15.2009.gif]. These cool anomalies have been there for at least several years. This cool region is also undoubtedly related to the above average Antarctic sea ice areal coverage that has been monitored over recent years; see http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.south.jpg]. 4. In Figure 2 of their paper, much of their analyzed warming took place prior to 1980. For East Antarctica, the trend is essentially flat since 1980. The use of a linear fit for the entire period of the record produces a larger trend than has been seen in more recent years. In terms of the significance of their paper, it overstates what they have obtained from their analysis. In the abstract they write, for example, "West Antarctic warming exceeds 0.1C per decade over the past 50 years". However, even a cursory view of Figure 2 shows that since the late 1990s, the region has been cooling in their analysis in this region. The paper would be more balanced if they presented this result, even if they cannot explain why.

Scientist adjusts data -- presto, Antarctic cooling disappears - December 21, 2008: Abstract excerpt: "We use statistical climate field reconstruction techniques to determine monthly temperature anomalies for the near-surface of the Antarctic ice sheet since 1957. Two independent data sets are used to provide estimates of the spatial covariance patterns of temperature: automatic weather stations and thermal infrared satellite observations. Quality-controlled data from occupied instrumental weather stations are used to determine the amplitude of changes in those covariance patterns through time. We use a modified principal component analysis technique (Steig et al., in review, Nature) to optimize the combination of spatial and temporal information. Verification statistics obtained from subsets of the data demonstrate the resulting reconstructions represent improvements relative to climatological mean values." Mann's not the only one inventing his own "modified" PCA. Looks like Steig "got rid of" antarctic cooling the same way Mann got rid of medieval warming. Why not just look at the station data instead of "adjusting" it (graph above)? It shows a 50-year cooling trend.

More here (See the original for links, graphics etc.)

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