2010 Diary week 26
Global warming, climate change and weather extremes
Book Review
Part II of the review of Hell and High Water: Global Warming – the Solution and the Politics – and What We Should Do by Joseph J. Romm will be posted shortly. These are some snippets: “Sea-level rise of 20 to 80 feet will be all but unstoppable by mid-century if current emissions trends continue. The first few feet of sea-level rise alone will displace more than 100 million people worldwide and turn all of our major Gulf and Atlantic coast cities into pre-Katrina New Orleans – below sea level and facing super-hurricanes.” “Global warming tends to occur faster at high latitudes, especially in the Arctic. This leads to more snow and ice melting, further decreasing Earth’s reflectivity (albedo), causing more heating. At the North Pole the summer ice cap has shrunk more than 25% from 1978 to 2005, a loss of 500,000 square miles of ice, an area twice the size of Texas.” “Jakobshavn Isbrae is Greenland’s largest outlet glacier, draining 6.5% of the entire ice sheet’s area. From 1950 to 1996, the glacier’s terminal point, or calving front, was stable, fluctuating about 2.5 kilometers back and forth around its seasonal average.” “Satellite images found that in October 2000, this pattern of stability changed when a progressive retreat began that resulted in nearly complete disintegration of the ice shelf by May 2003.” “A 2006 study found a similar change in two East Greenland outlet glaciers – Kangerdlugssuaq and Helheim. The top surface of Helheim dropped more than 150 feet in two years. The surface of Kangerdlugssuaq dropped more than 250 feet. The two glaciers together drain about 8% of Greenland’s ice sheet.” “A 2004 study noted that over the previous decade the grounded Amundsen Sea portion of the West Antarctic Ice Sheet has been losing 50 cubic kilometers of volume each year and that ice shelves in Pine Island Bay have been thinning by up to 5.5 meters per year. The reason appears to be ocean currents averaging 0.5°C warmer than freezing.”