4 December 2012

New Science On Sea Level Rise Indicates Greenland And Antarctic Ice Melt Increasing.

Posted by Dan Satterfield

Ross Island Antarctica. Dan's Picture.

Superstorm Sandy was a devastating tragedy, but if something like that could have a silver lining then the new public awareness of sea level rise is perhaps it. Just weeks after Sandy, comes a major paper in Science. The paper is the result of a collaboration by the top experts studying the mass balance of polar glaciers. If you get a chance, pick up a copy of Science and read Richard Kerr’s summary of the paper (as well as the paper itself actually).

While there has been a lot of disagreement among the different methods of measuring the ice loss in polar regions, it now looks as if there has been real progress. The project was called IMBIE or Ice sheet Mass Balance Inter-comparison Excercise. In short all the researchers got together and reconciled their data.

The result:

Ice regions at the poles are losing  344 billion tons of ice every year. 263 billion tons of that melt is in Greenland, and all that melting ice is responsible for 20% of the observed sea level rise. The rest is from thermal expansion of seawater (around 70 centimeters per degree C) as the oceans warm and also from melting glaciers on mountains. Researchers are finally gaining an understanding of the sensitivity of the ice melt to rising temperatures and the news is not good. There is now solid evidence that a rise in sea level of a meter is very likely in the next century and this means events like Sandy will no longer be once in a century events.

Last month, I did an on air report on what just 70 cm of sea level rise will do here on Delmarva at Assateague Island National Seashore. The SLAMM model data is below and it speaks for itself. Keep in mind that a 70 cm rise is considered TOO LOW by nearly every researcher in the field.

SLAMM Model showing the effects of a modest rise in sea level at Assateague Seashore in Maryland.

Keep in mind that once sea level rises just 30 CM, it will only take a much weaker version of  a Hurricane Sandy to cause the same damage. Sea level rise is not something that will sneak up on us, instead It will be felt all at once on, a dark stormy night when a hurricane or nor’easter hits the coast. The damage will be blamed on the storm, but the rising seas will be the hidden culprit. Just like they were in Sandy.