Tuesday, October 27, 2009
Reference: Melting glacier uncovers island, cnet news, April 28 2007
A well circulated article about global warming compares Landsat phtotos taken on 8/11/1985 and 9/5/2002 and claims that carbon dioxide from fossil fuels is melting the icesheet over Greenland and exposing rocky peninsulas previously covered by ice (Melting glacier uncovers island, April 28, 2007). Please note that a significant amount of summer melt takes place between these dates. The comparison does not yield trend information from year to year because it is confounded by seasonal changes. To draw conclusions about long run trends in ice mass once would have to compare the ice on the same date for more than just two arbitrary years neither of which is recent.