UN Study Erred on Glacier Size, Melting Rate, Scientists Say
By Alex Morales
Jan. 21 (Bloomberg) -- A single paragraph in the United Nations’ most comprehensive report on climate change contains three factual errors, scientists said.
The UN Intergovernmental Panel on Climate Change, or IPCC, said in the 2007 report that Himalayan glaciers are receding faster than elsewhere when they are not, overestimated the area covered by the Asian ice masses by a factor of 15 and said they may shrink four-fifths by 2035 rather than 2350, four researchers said in a letter to the journal Science.
“These errors could have been avoided had the norms of scientific publication, including peer review and concentration upon peer-reviewed work, been respected,” the researchers based in the U.S., Canada and Austria wrote.
The Nobel Prize-winning IPCC has come under fire from global-warming skeptics for exaggerating glacier melt, prompting its chief, Rajendra Pachauri, to say the panel will re-examine the findings. India Prime Minister Manmohan Singh’s special envoy on climate change, Shyam Saran, said yesterday that his country plans a comprehensive study of glacial melt.
“In drafting the paragraph in question, the clear and well-established standards of evidence, required by the IPCC procedures, were not applied properly,” the UN panel said late yesterday in a statement posted on its Web site.
The researchers who wrote to Science are Georg Kaser, professor of glaciology at the University of Innsbruck, Austria; Graham Cogley, a professor of geography at Trent University in Peterborough, Canada; Jeffrey Kargel, a researcher at the University of Arizona in Tucson; and Cornelis van der Veen, a professor of geography at the University of Kansas in Lawrence.
Kaser, who contributed to the 2007 report though not the chapter in question, said today in a telephone interview that glaciers are “dramatically melting around the world” and that the errors will be welcomed by climate-change skeptics. He also said his confidence in the IPCC’s work is “unbroken.”
“Compare it with a huge buffet, and a lot of cooks have contributed, and when it came to this little bit of mayonnaise something went wrong but the rest of the buffet is perfect,” Kaser said.
The passage under debate is attributed to a 2005 report by the environmental group WWF and states:
“Glaciers in the Himalaya are receding faster than in any other part of the world and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate. Its total area will likely shrink from the present 500,000 to 100,000 km2 by the year 2035.” A half-million square kilometers is about 200,000 square miles.
The 2035 date has already been subject to criticism amid claims it stemmed from a 1999 article in the New Scientist magazine, which the WWF report cited. Syed Iqbal Hasnain, the Indian researcher quoted in the New Scientist piece, told Bloomberg in a Jan. 19 interview that he was “misquoted.” The article’s author, Fred Pearce, said he stands by his report.
“I stand by my report of what Hasnain told me 11 years ago,” Pearce said today in an e-mail. “I have been in touch with him since, including last week, and he has never complained to me about it.”
The letter to Science said that the extent given for Himalayan glaciers in the IPCC report of 500,000 square kilometers may refer instead to the global total area of glaciers and ice caps because the Asian mountain range contains only about 33,000 square kilometers of glaciers.
Another error identified by the researchers is the claim that Himalayan glaciers are receding faster than those elsewhere. The rate of retreat isn’t “exceptional,” they wrote, citing a study of melt from 2000 through 2005 by the World Glacier Monitoring service in Switzerland.
The researchers said that rather than the New Scientist piece, the source of the 2035 date may be a transposition of numbers from a 1996 study that said the global extent of glaciers may shrink to 100,000 square kilometers by 2350.
“This number is so entirely wrong” that it would entail raising the level at which summer temperatures are at freezing point from about 5,000 meters (16,000 feet) to the summit of Mount Everest, which stands at 8,850 meters, Kaser said. “That would require a warming of 18 degrees Celsius (32 Fahrenheit).”