The fate of FL and LA if we’re myopic and greedy enough to let the West Antarctic Ice Sheet (WAIS) collapse [click to see entire SE coast].
A new study in Science finds that sea level rise from a collapse of the WAIS would likely be 25% higher for North America than previously estimated:
The catastrophic increase in sea level, already projected to average between 16 and 17 feet around the world, would be almost 21 feet in such places as Washington, D.C., scientists say, putting it largely underwater. Many coastal areas would be devastated. Much of Southern Florida would disappear.
This article has already started to make news around the globe (Reuters story here). But, frankly, divining the difference between a rise of 16.5 feet (an incalculably devastating catastrophe) and 21 feet (an incalculably devastating catastrophe) is like trying to count the number of devils on a pin.
Nonetheless, WAIS collapse is all but inevitable given business-as-usual warming of 5-7°C. As I explained in my book:
Perhaps the most important, and worrisome, fact about the WAIS is that it is fundamentally far less stable than the Greenland ice sheet because most of it is grounded far below sea level.
For a longer discussion of WAIS and its unique instability, see “Antarctica has warmed significantly over past 50 years.”
So what is new in the Science article, “The Sea-Level Fingerprint of West Antarctic Collapse” (subs. req’d)? Study coauthor and geophysicist Jerry X. Mitrovica, director of the Earth System Evolution Program at the Canadian Institute for Advanced Research, explains: