Twitter button

Thursday, May 31, 2012

More eye-popping Greenland data

Over at Weather Underground, meteorologist Dr. Jeff Masters has a new post on Greenland, including some recent temperature records and a look at the melting of the giant island's ice cap during 2011:

"The record books for Greenland's climate were re-written on Tuesday, when the mercury hit 24.8°C (76.6°F) at Narsarsuaq, Greenland, on the southern coast. According to weather records researcher Maximiliano Herrera, this is the hottest temperature on record in Greenland for May, and is just 0.7°C (1.3°F) below the hottest temperature ever measured in Greenland. The previous May record was 22.4°C (72.3°F) at Kangerlussuaq (called Sondre Stormfjord in Danish) on May 31, 1991. ...

"Between 2003 - 2009, Greenland lost an average of 250 gigatons [billion tons] of ice per year. In 2011, the loss was 70% greater than that." (This is accompanied by a seriously scary graph showing ice loss from 2003 to 2011.)

To briefly recap the nature of the problem:

- The Greenland ice cap is one of the world's two major land-based ice accumulations along with Antarctica.  "Land-based" is key because when land-based ice melts, it adds to sea level rise. (The Arctic ice cap floats on the ocean, so while it is melting too, that doesn't change sea level.)

- There is enough ice in Greenland's mile-high ice cap to raise global sea levels by 7 meters (23 feet) if it all melts (although that's expected to take hundreds of years to happen).

- Many millions of people live in low-lying coastal areas around the world that will have to be abandoned if sea level continues to rise.

Dr. Masters cites studies that estimate Greenland's current contribution to sea level rise at just 0.7 mm (.03 inches) per year, and expect that rate to double over the next decade.

So, nothing urgent here, just another trend that is headed in the wrong direction and accelerating.  On the other hand, it's also a process that may not be entirely predictable.  See Science News, April 16, 2012, "Greenland may be slip-sliding away due to surface lake melting."

No comments:

Post a Comment