Friday, April 22, 2016

Fate of World’s Coastlines Rests on Melting Antarctic Ice

Scientists are trying to figure out how Antarctica will respond to warming temperatures. (Credit: Michael Studinger, NASA/Flickr) Click to Enlarge.
Instead of the anticipated several feet of sea level rise this century if current pollution rates continue, the latest modeling-based science warns that melting could lead to twice that amount.  That sobering estimate is a rough one.

If the Paris agreement fails to substantially curb global warming, the latest projections suggest places like Tybee Island, which has an average elevation of less than 8 feet, could effectively be doomed.
Rising seas wouldn’t be the only consequences of extensive ice sheet melting, which can also pour cold water on influential ocean currents, profoundly changing them. A lengthy hypothesis published in a scientific journal by former NASA climate scientist-turned-climate activist James Hansen last month speculated that rapid Antarctic melting would lead to superstorms, weather changes and “practically incalculable” flood damages.

The oceans are rising globally by about an inch per decade — and that rate is hastening as carbon dioxide, methane and other greenhouse gases continue to warm the planet’s surface. Global temperature records were set in 2014 and again in 2015, and in each of the first three months of 2016 due to global warming and a strong El Niño.

East Coast sea level rise has recently been worse than elsewhere, amplified by natural geological processes and by regional changes to ocean currents.
The latest Antarctic ice sheet modeling research suggests the problem of sea level rise this century could be twice as severe as previously anticipated, fueled by the collapse of eroding cliffs of Antarctic ice.

In that paper, published last month in Nature, UMass professor Rob DeConto and Penn State scientist David Pollard developed an ice sheet model and used it simulate the effects of two processes they think could be crucial. Meltwater seeped into the ice sheet in the model and cracked it, exposing towering cliffs of ice that toppled under their own weight into the Southern Ocean.

Read more at Fate of World’s Coastlines Rests on Melting Antarctic Ice

No comments:

Post a Comment