Everyone agrees that if the ice-caps on Greenland and Antarctica melt, the seas will rise. What is difficult is to estimate how fast this may happen, with the ongoing rise in global temperature. Recent measurements of sea-level rise hover about 3.5 mm/year—or about a foot and a half by the end of the century. The highest estimates puts the rate of rise at about twice that fast.
We know that these polar ice packs have waxed and waned in the past, especially at the beginning and end of glacial epochs. What do past fluctuations in the ice tell us?
A recent study, published in the journal, Nature, should give us pause. First, the scientists found that there is a rapid coupling between temperature changes and the mass of ice at the poles. We can expect a response of Greenland and Antarctica to rising temperature during this century.
Second, and perhaps more sobering, is the observation that sea level has risen as fast as 4 feet per century during warm intervals of the past 150,000 years. Our current estimates of sea-level rise may be very conservative.
This is not welcome news to those who live near coastal areas, to residents who strive to rebuild on Staten Island and the coast of New Jersey, nor to condominium dwellers in Miami. We can, of course, fight back against the sea, but only with enormous cost and the likelihood of long-term failure. It’s time to move away from the coast and get serious about global climate change.
Photo, taken on March 16, 2009, courtesy of Avery Studio via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY, with partial support from the Field Day Foundation.