ENVIRONMENT - Greenland Ice Sheet Melts in 4 Days

"Greenland Goes Green: Ice Sheet Melted in Four Days" PBS Newshour 7/25/2012

Excerpt

SUMMARY: On July 8, NASA satellite imagery showed about 40 percent of Greenland's top ice layer intact. By July 12, only four days later, 97 percent of the ice had melted. Margaret Warner asks NASA's Thomas Wagner for scientific explanation of the massive thaw.

Significant excerpt

MARGARET WARNER: So, you're basically talking about the weather?

THOMAS WAGNER, NASA: Yes, and that is one way to thing about it. Climate is sort of long-term weather. But short term, you can get extreme variations. And we're seeing an extreme variation in Greenland.

MARGARET WARNER: So, you're saying you can't really attribute this to climate change?

THOMAS WAGNER: No.

And that's one of the things. We spent a long time trying to word the document that we put out describing it. And we said, look, there is evidence that this has happened before. Now, that doesn't mean -- we really don't know the explanation for this one. If it happens again, if it starts to happen repeatedly, then we have an indication that there might be a real shift going on in the Arctic system there.

NASA Images

CLIMATE - Ice Sheets Melting Much Faster

"No Dice for Greenland Ice" by Phil Berardelli, ScienceNOW Daily News

Something ominous may be happening beneath Greenland's vast ice sheet. For nearly 50 years, the world's second largest ice cap has inched inexorably downhill toward the ocean, but at a stable rate. Now, the sheet seems to be melting and sliding seaward much faster, and the rate seems to be accelerating--a condition that could eventually endanger coastal populations and affect Earth's climate.

When glaciers begin to melt, water works its way down to the bottom of the ice. There it lubricates the glacier, which will pick up its downhill pace. Why worry? Greenland holds about 10% of the world's ice, so if it melts completely--though an unlikely prospect--it would raise global sea level about 6.5 meters. That's enough to flood all of the planet's coastal cities and displace billions of people.