From White to Green - Greenland's Glaciers are History
Take a long hard look at Greenland's towering glacial caps - they may well already be history. That's according to a new paper out yesterday Nature Climate Change. Scientists have already seen the speed at which Greenland's glaciers are rushing into the sea accelerate. And they have long-feared that, without commitments to curb our greenhouse gas emissions, much of its ice cap will eventually disappear into the sea.
This new research suggests that threshold has already been passed. Previous models made some pretty simple assumptions about how the 2 mile-thick ice block, which is plastered over much of Greenland, will melt. And they gave some hope that the worst of the melting could still be avoided, if we pulled the plug on our emission.
A truly green land. With this new research, however, the physics of Greenland's ice-melting process have been painted out in finer detail. And if the authors are right, the amount of global warming we have stored up, from our emissions so far, may be enough to transform Greenland. The world's biggest island could shift from an icy whiteness to a truly green land.
The reason for the change in outlook? The simple realization that as the 2-mile high icy plateaus melt they get considerably lower. And the lower the ice surface, the warmer the air above them gets, pushing the pace of melt even faster – a positive feedback.
Positive feedbacks are the 'loaded dice' of the game of climate crap-shoot we're playing. They push the odds in favor of dangerous consequences, by accelerating the initial rates of change, kicked off by global warming. But how dangerous would it be, if Greenland were to disgorge it's entire ice sheet into the oceans, as this study suggests?Continued on the next page