The ebb and flow of glacial lakes

800px-Quelccaya_Glacier

The Quelccaya Glacier in Peru is the largest glacier in the tropics. This glacier provides water to the city of Lima and contributes to hydroelectric power. In the last fifteen years, it has retreated nearly 195 feet per year. The increasing presence of glacial lakes around it reflects its unprecedented recession. Photo credit: Edu Bucher (http://en.wikipedia.org/wiki/File:Quelccaya_Glacier.jpg)

People sometimes ask us what it means if the world’s glaciers melt because of warmer temperatures. As Earth’s climate warms, the fate of the world’s shrinking glaciers matters to people who depend on them for meltwater. An increase in glacial lakes may mean more water for the present but leaves many to wonder how reliable this source of water will be if glaciers continue to recede. But what are glacial lakes and how do they form? Are they a part of a normal, healthy glacier, or evidence of glacier decline? Continue reading

A thawing, rotting Arctic?

Permafrost thaw causes the ground to become unstable as the soil collapses. This can damage building and roads built on permafrost. Cracks also expose the carbon stored within to sunlight, which may speed the release of carbon dioxide, a greenhouse gas. Photo credit: Dentren (http://upload.wikimedia.org/wikipedia/commons/a/ac/Storflaket.JPG)

Permafrost thaw causes the ground to become unstable as the soil collapses. This can damage building and roads built on permafrost. Cracks also expose the carbon stored within to sunlight, which may speed the release of carbon dioxide, a greenhouse gas.
Photo credit: Dentren (http://upload.wikimedia.org/wikipedia/commons/a/ac/Storflaket.JPG)

As greenhouse gas emissions continue to rise, researchers are looking at a source of even more carbon emissions: thawing permafrost. A warming Arctic may cause significant amounts of dead, organic material currently frozen in permafrost to thaw out and decay, releasing more carbon into the atmosphere. How exactly does permafrost store carbon? And what are the consequences if the permafrost thaws?

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