Sizing up Rising Sea Levels

Measuring ice sheet melt helps to forecast when and by how much sea level is to rise.

Climate change scientists are starting to generate hard evidence that will help policy and decision-makers worldwide take effective action against rising sea levels. At the forefront of this work, Living With Environmental Change-accredited research led by the British Antarctic Survey is now developing a clearer picture of how melting ice sheets and glaciers will affect the size and timescale of the rises.

“Over the next 30 years, an annual increase of 3-4mm is inevitable,” says Professor David Vaughan of the British Antarctic Survey, who is leading the Ice Sheets and Sea Level Rise Programme. “But we’re also zeroing in on specific locations in Antarctica which will tell us what’s likely to happen on a timeframe of 100 to 150 years. That data will be critical to future decisions on investment in stronger sea defences and adaptation strategies.”

Particular attention is focusing on the Amundsen Sea embayment. On-site surveys, satellite studies and computer models have revealed that this location is losing ice faster than anywhere else on Earth. The probable cause is ocean water, warmed by climate change, feeding into the area through channels in the continental shelf. Better understanding of processes like this is crucial to producing more robust estimates of long-term ice melt.

The data emerging will constitute vital input to the Fifth Assessment of the Intergovernmental Panel on Climate Change, due for publication in 2013. “Ten years ago we knew very little, but that’s no longer the case,” Professor Vaughan comments. “Combating rising sea levels will mean doing the right thing at the right time. Our work is providing the platform to make it possible.”