A NASA report describing an "unprecedented" instance of ice melting in Greenland has sparked a new debate about global warming and has elicited accusations that the space agency has become politicized where climate science is concerned.
97 percent of Greenland's ice sheet melted in July
According to the report, NASA satellite data suggests that at one time or another 97 percent of the ice sheet that covers Greenland had thawed due to the persistence of a warm air mass over that land mass. Ordinarily roughly half of Greenland's ice sheet melts at one time or another during the summer. Scientists are not certain whether the phenomenon will increase the overall loss of ice in Greenland and cause the surface levels of the ocean to rise. The ice appears to be refreezing, however.
Unprecedented except where it is not
The controversy that has arisen as a result of the report is due to the use of the word "unprecedented" in the title of the report. However, down toward the bottom of the NASA report, Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data suggested that events such as these occur naturally every 150 years. Ice core data seem to confirm this finding.
The question of climate change
The NASA findings have caused some speculation in the media whether the "unprecedented" ice sheet melt is being caused by climate change, or as it is sometimes called, global warming. While NASA itself has not suggested that the ice sheet melt was caused by man caused global warming, which is said to be caused when carbon dioxide pumped into the atmosphere by power plants and factories trap the heat of the sun, a story in NPR was not so coy. NPR quotes other news outlets such as Wired and the UK Guardian that the phenomenon is evidence of global warming.
Climate change skeptics pounce
Fox News, on the other hand, quotes a number of climate change skeptics who suggest that fears that the Greenland ice sheet is being melted by man-caused global warming over overblown. Patrick J. Michaels, a climatologist, suggests in his blog that NASA is guilty of illiteracy by misusing the term "unprecedented" for something shown to have occurred every 150 years. Anthony Watts, a climate skeptic who runs a blog called Watts Up With That, suggests that the notion that global warming is causing the ice sheet melt in Greenland is similar to claims that droughts in North American are being caused by the same phenomenon.
Temperatures rising in Greenland
Fox News also quotes NASA's chief cryospheric scientist H. Jay Zwally as suggesting that temperatures over Greenland are rising faster than over the rest of the globe, contributing to the ice sheet melt. This in itself is not proof of global warming, however, and may be part of the 150-year natural cycle.
Mark R. Whittington is the author of Children of Apollo and The Last Moonwalker. He has written on space subjects for a variety of periodicals, including The Houston Chronicle, The Washington Post, USA Today, the L.A. Times, and The Weekly Standard.
- Nature & Environment
- Science, Social Science, & Humanities
- global warming
- climate change
- Greenland ice sheet