Glacier melting stories defy science

Glacier melting stories defy science
April 1, 2001

There's been a spate of stories--by Reuters, Associated Press, BBC, the London Times, and The Washington Post, among others--that report receding ice in the remote Antarctic Pine Island glacier.

Despite protests by Andrew Shepard, who is senior author of an article in the February 2 edition of Science upon which these reports are based, each and every story either links his findings to global warming or suggests a possible relationship. "We don't have any evidence to suggest change of climate," Shepard told Reuters. Nevertheless, the media insist on guilt by implication, imputing something when there are no facts to support it and despite expert testimony to the contrary.

Coverage of climate change issues by the media seizes upon any scientific finding that seems to be consistent with warming and automatically assumes a relationship. Thus, after quoting Shepard, Reuters reports just one paragraph later, "Researchers say large chunks are breaking off of Antarctica for several reasons, some due to global warming . . . if the ice melts it could not only raise ocean levels but could shift ocean circulation and weather patterns, bringing drought, severe storms, and the wider spread of tropical diseases."

AP's coverage quotes Jane Ferrigno of the U.S. Geological Survey as saying this is "a yellow warning flag." Having manufactured that fear, AP concludes, "Melting all the Antarctica ice would cause a global sea level rise of 240 feet." Thus, the scientific equivalent of a snow flurry is hyped into something like an Ice Age.

The fact is, the Science article's authors conclude that if the entire Pine Island system (which isn't anchored on land) melts, the rise in sea level would be 1/4 inch!

How does AP manage to magnify potential for sea level rise by a factor of 12,000? By virtue of a nonsense calculation that assumes a complete Antarctic meltdown-- something that would require at least 100,000 years and which is impossible within the time frame of the Fossil Fuel Age.

One could argue that what is going on at Pine Island is happening all over Antarctica, and possibly is symptomatic of global warming. It's pretty easy to check that premise, but it proved too difficult for the reporters involved . . . or the outcome proved to be inconsistent with the gloom-and-doom patina they preferred to apply to Shepard's study.

Two independently collated studies of the entire Antarctic temperature record--one by renowned NASA scientist James Hansen and the other by the UN's Intergovernmental Panel on Climate Change (IPCC)--show identical results: No Antarctic warming in the last 40 years. In fact, as shown in the figure below, since 1979 there has been a statistically significant decline in Antarctic average temperature. Go figure (or don't, depending upon your predisposition).

The soon-to-be-released Third Scientific Assessment of the IPCC notes:

Some important aspects of climate appear not to have changed.

  • A few areas of the globe have not warmed in recent decades, mainly over some parts of the Southern Hemisphere oceans and parts of Antarctica.

  • No significant trends of Antarctic sea-ice extent are apparent since 1978, the period of reliable satellite measurements.

Figure 1. Annual temperatures averaged over the region from 64 S to 90 S latitude, which wholly encompasses Antarctica, shows that there has been a statistically significant decline in temperatures since 1979 (data from Goddard Institute for Space studies, http://www.giss.nasa.gov/data/update/gistemp/).