The peer-reviewed study, funded by the National Science Foundation is the first to attribute a specific proportion of the ice melt to greenhouse gases and particulates from pollution.
The study used supercomputers and one of the world's most sophisticated climate models to reach its conclusions, said lead author Jennifer Kay, a staff scientist at the National Center for Atmospheric Research in Boulder, Colo. The paper was published last week in the scientific journal Geophysical Research Letters.
Kay said her study was an attempt to learn how much Arctic Ocean melting can be attributed to "natural variability" - complex changes wrought by nonhuman forces - and how much has been caused by greenhouse gases such as carbon dioxide and by atmospheric particulates.
In doing so, she was also able to look ahead to future annual and decade-long fluctuations. She and the other authors said conditions will become more volatile from year to year. That means there will be years and perhaps decades when the ice pack expands. But the trend is in the other direction.
"There's no doubt about it - sea ice is going away," she said. "What we found was that about half of that trend is related to the increasing greenhouse gases." The other half of the sea-ice loss, as observed over the late 20th century, was "just related to variability in the system." Read the full report here.
Source: by Richard Mauer, Anchorage Daily News, Miami Herald.com.
