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This research is conducted in association with the��program in Toolik Lake, Alaska, which is directed by �������� Ecosystems Center scientist Ed Rastetter and includes ecologists from �������� and 21 other institutions.

Winter ice deposits that form on top of Arctic rivers and provide crucial water for ecosystems in the summer are melting far earlier with each successive year.

These arctic river icings, which can be up to 33 feet thick, multiple kilometers wide and stretch tens of kilometers in length, disappeared on average 26 days earlier in 2015 than they did in 2000, according to a study��.

“The average trend in disappearance date is more than a day per year. That’s really fast. These changes are not subtle,” said Tamlin Pavelsky, a hydrologist at the University of North Carolina Chapel Hill and the study’s co-author.

Climate change research tends to focus on glaciers, which provide a continuous source of meltwater for rivers, at least until they disappear completely. Arctic river icings create less continuous and more fluctuating sources of meltwater, but cover a larger total area than glaciers do.��

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