Monday, April 16, 2012

Lopsided melting discovered along Himalayan glaciers

Jennifer Welsh in LiveScience: Glaciers and sea ice around the world are melting at unprecedented rates, but new data indicates that this phenomenon may be lopsided. It seems that some areas of the Himalayan mountain range are melting faster than others, which aren't melting at all, a new study indicates.

Specifically, the Karakoram mountain range is holding steady, and may even be growing in size, the study, published in the April 2012 issue of the journal Nature Geoscience, suggests. "The rest of the glaciers in the Himalayas are mostly melting, in that they have negative mass balance, here we found that glaciers aren't," study researcher Julie Gardelle, of CNRS-Université Grenoble, France, told LiveScience. "This is an anomalous behavior."

The Karakoram mountain range spans the India-China-Pakistan border. It is home to the world's second highest peak, K2, and has the highest concentration of peaks over 5 miles (8 kilometers) high in the world. It is home to about half of the volume of the Himalayan glaciers.

...The researchers used satellite photos to analyze the extent of the ice in about a quarter of the total range — about 2,167 square miles (5,615 square kilometers). The photos were taken in 1999 and 2008. The researchers used two computer models to translate the images, revealing the elevation of the glaciers and estimating the extent of the ice.

They found that the glaciers are holding steady and based on the numbers might actually be gaining mass. But Gardelle warns this doesn't mean global warming and glacier melt isn't happening elsewhere. "We don't want this study to be seen as questioning the planet's global warming," she told LiveScience. "With global warming we can get higher precipitation at high altitudes and latitudes, so thickening isn't out of the question."...

Snow Lake, the glacial basin at the head of Biafo and Hispar glaciers in Pakistan's portion of the Karakoram range. Shot by Dave Hancock (http://www.fieldtouring.com), Wikimedia Commons, under the Creative Commons Attribution-Share Alike 2.5 Generic license

No comments: