In recent years there has actually been more rain and snow in this region than a couple of decades ago.
But because of global warming, the summers are warmer, so the ponds are losing more water to evaporation—greater than the gain from the extra precipitation.
So like a pot of simmering stew, the ponds are becoming smaller and saltier.
Of the 24 or so ponds that Smol and Douglas were tracking, all were drying and shrinking, and two or three went completely dry in the summers of 2005 and 2006.
"We've seen, in our lifetime, in front of our eyes, some of these ponds dry up," Smol said. "It is quite striking."
In wetter years the now-dry ponds may again fill with water, Smol said.
But they won't be the same again, he says, since many of the organisms that once lived in the ponds have probably died.
More to Come
"The disappearance of lakes is occurring widely across the Canadian, Alaskan, and Siberian Arctic," said Larry Hinzman of the University of Alaska at Fairbanks.
A 2005 study by Hinzman and his colleagues showed lakes are also disappearing in Siberia, just south of the Arctic Circle.
Scientists speculate that there the permafrost beneath the lakes has been melting, draining the water like pulling the plug on a bathtub.
Another study last year used satellite photos to show that lakes in Alaska were also shrinking.
"These shrinking lakes will have a drastic ecological impact, which will reverberate through the northern life cycle," Hinzman said.
It will hurt migratory waterfowl and the people who depend on the lakes for subsistence hunting and fishing, he pointed out.
And there's more drying in store, he said.
"This will certainly continue, and probably accelerate for the foreseeable future."
The Arctic ponds in the new study "are like the miners' canaries of the planet," study leader Smol added, "showing the first signs of warming."
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