Tuesday, January 18, 2011;
This story may be a little hard to believe, especially a day after most kids had a day off from school because of ice, but here goes:
Scientists are reporting that the shrinking ice and snow cover in the Northern Hemisphere is adding to the problem of global warming in a way that they had not anticipated. Arctic sea ice, glaciers and snow are reflecting less energy back to space than they were 30 years ago, according to a University of Michigan study.
Scientists say that what was once covered in ice and snow is now land and water, which are darker and absorb more heat than the white ice. As a result, the amount of solar energy being reflected to the Earth's upper atmosphere has decreased since the late 1970s.
Scientists add that other factors could be causing the decrease but that the decline is more than they had expected.
Temperatures in the Northern Hemisphere have risen by about 0.75 degrees Celsius in the past three decades. The study did not look at the Southern Hemisphere, where Antarctica has far more ice, is much colder and shows fewer signs of warming.