Field Notes: The Polar Field Services Newsletter

In The News

A supraglacial lake on the western margin of the Greenland Ice Sheet. Photo: Laura A. Stevens

A supraglacial lake on the western margin of the Greenland Ice Sheet.
Photo: Laura A. Stevens

Geoscientists Solve “Disappearing Lake” Mystery

The Christian Science Monitor reports the findings of a study published June 3 in Nature that investigates how large glacial lakes in Greenland can completely drain billions of gallons of water in a matter of hours. The story begins with an eye-popping anecdote: “In 2006, Greenland’s North Lake, a 2.2 square-mile (5.6 square kilometers) supraglacial meltwater lake, drained almost 12 billion gallons of water in less than two hours. In a study published two years later, researchers determined that this astonishing phenomenon is possible because giant hydro-fractures (water-driven cracks) can form directly beneath the lake basin and stretch down to the bed of the ice sheet, emptying the lake of water. But just how these fractures developed has been unknown — until now.”

The cause of the fractures, according to the study, is tension related stress caused by movements of the ice sheet that are triggered by trickling meltwater. Click here for the entire story.

Everest Glaciers Predicted to Melt by 2100

The New York Times reports that climate models show the Everest region of Nepal could lose most of its glaciers by the end of this century, according to a study published in the journal The Cryosphere. The scientists’ computer model accounted for glacier melt, accumulation and redistribution and was customized with data on temperature and precipitation, measurements from the field and remote-sensing observations collected over 50 years from the Dudh Koshi basin, which includes Mount Everest and several of the world’s other highest peaks. Read the entire story here.

Alaska’s Hubbard Glacier Advancing

Not all glaciers are shrinking. Part of Alaska’s Hubbard Glacier has been advancing into Disenchantment Bay for more than 100 years, according to NASA’s Earth Observatory. In addition to its movement, the glacier has been thickening as well, bucking the worldwide trend of thinning, shrinking glaciers, reports weather.com.

This image was captured on July 22, 2014, by the Operational Land Imager (OLI) on Landsat 8. Then, yellow lines were placed over the current image to show where the terminus, or lowest point on a glacier, was located in 1978 and 2002, demonstrating the glacier is creeping further into Disenchantment Bay. Photo: NASA Earth Observatory

This image was captured on July 22, 2014, by the Operational Land Imager (OLI) on Landsat 8. Then, yellow lines were placed over the current image to show where the terminus, or lowest point on a glacier, was located in 1978 and 2002, demonstrating the glacier is creeping further into Disenchantment Bay. Photo: NASA Earth Observatory

Sea Ice Update

The National Snow and Ice Data Center (NSIDC) reports that melt season is underway, and sea ice in the Arctic is retreating rapidly. At the end of May, ice extent was at daily record low levels. By sharp contrast, sea ice extent in the Southern Hemisphere continues to track at daily record high levels.