The West Antarctic Ice Sheet: Five Million Years of History
31.08.2009 - Other
The current melting of the great polar ice sheets and the resulting rise in global sea level underline the fragility of the West Antarctic Ice Sheet (WAIS). If floating ice shelves attached to the WAIS were to melt sufficiently, the grounded ice upstream would flow faster and drain the ice from the interior of the ice sheet, eventually causing the collapse of the entire ice sheet on the Pacific side of Antarctica.
With their computer model of the WAIS over the last 5 million years, David Pollard, a senior research scientist at Penn State, and Robert M. DeConto, professor of climatology at the University of Massachusetts, have been able to show that the West Antarctic Ice Sheet has varied a lot over time. These changes, however, appear to have been due to temperature changes in the oceans and were more likely to take place when atmospheric carbon dioxide levels were at about 400 parts per million.
Furthermore, in comparing their model to the early results of the ANtarctic geological DRILLing project (ANDRILL), the scientists extended the reach of the existing data from the drilling site to the entire West Antarctic area.
The next steps to be taken in research will be aimed at determining whether human activity will make it warm enough to trigger the collapse.
