Projected sea level rise is twice previous estimates

Researchers said yesterday that the potential rise in global sea level by the year 2100 could be almost double the previous estimates. A rise of this magnitude could affect a tenth of the world’s population.

At the International Scientific Congress on Climate Change in Copenhagen, Denmark this week, Konrad Steffen of the University of Colorado at Boulder chaired a session on sea level rise. He said that the upper range of sea level rise by 2100 might be one meter or more on a global average, with large regional differences based on factors like sea ice melting.

Current estimates from the 2007 Intergovernmental Panel on Climate Change report project average sea level rises of 18-59 centimeters.  This report, however, had insufficient data about how melting ice sheets contribute to sea level rise.  Eric Rignot of the University of California Irvine and NASA’s Jet Propulsion Laboratory said that results from the last two to three years give a clearer picture of ice sheets’ effects on sea levels. The ice sheets in Greenland and Antarctica are already contributing more and faster to sea level rise than anticipated, he said, stating that if the trend continues, sea level could rise by a meter by 2100.

Previous studies have shown that about a tenth of the world’s population lives in low-lying areas that could be affected by such a drastic rise in sea levels. John Church of the Centre for Australian Weather and Climate Research said that in Australia, coastal flooding events that currently occur once every hundred years could happen several times a year by 2100.

The International Scientific Congress on Climate Change is taking place yesterday, today and tomorrow. Results from the meeting will be developed in a synthesis report to be published later this year and given to all participants at the United Nations Climate Change Conference (COP15)  in December in Copenhagen.

Read more about the Congress here.