Faster Rising Antarctic Waters: A Fresh Problem

The global sea level is rising, and waters around Antarctica are rising even faster. That is, according to a recent study that has found that Antarctic ice melt is causing coastal waters of the White Continent to rise at an unprecedented rate.

The study was recently published in the peer-reviewed journal Nature Geoscience, and includes satellite data from the last 19 years. Careful data analysis conducted by researchers at the University of Southampton has revealed that the sea-level around the coast of Antarctica has risen by a total of about two centimeters - more than the global average of six centimeters.

Two extra centimeters over nearly 20 years may not seem like much, but the study authors say that those centimeters are part of an excess of 350 gigatonness of freshwater that can be found in surrounding oceans.

"Freshwater is less dense than salt water and so in regions where an excess of freshwater has accumulated we expect a localized rise in sea level," Craig Rye, lead author of the study, explained in a recent statement.

According to Rye and his team, the satellite observations and computer modeling found that coastal waters in the immediate Southern Ocean are rising by an additional two millimeters each year. Some have previously argued that this apparent "rise" is actually caused by the coastal waters and icy shorelines being affected by the pressures of the White Continent's intense winds, but the new modeling claims differently.

"We can estimate the amount of water that wind is pushing on to the continental shelf, and show with some certainty that it is very unlikely that this wind forcing is causing the sea level rise," Rye told BBC News.

"The computer model supports our theory that the sea-level rise we see in our satellite data is almost entirely caused by freshening (a reduction in the salinity of the water) from the melting of the ice sheet and its fringing ice shelves," he added in a release.

"The interaction between air, sea and ice in these seas is central to the stability of the Antarctic Ice Sheet and global sea levels, as well as other environmental processes."

The study was published in Nature Geoscience on August 31.