Is declining sea ice changing the atmosphere?

Although Arctic sea ice extent did not set a low record this year, it’s still clear that there is less sea ice than there used to be. Scientists are keeping a close eye not only on the dwindling ice, but also on the ripple effect its loss might have on the rest of the Arctic environment. A big question involves the exchange of heat between ocean and air—and the weather patterns that result.  What does current research say about how floating ice—or the lack of it—might be changing the Arctic atmosphere? Continue reading

Are we cooling?

After a cool Arctic summer, sea ice at the North Pole has recovered somewhat from last year’s record low extent. While this is a welcome pause in the downward trend of sea ice extent, some are taking it a step further and hailing this rebound as evidence that the Arctic is no longer warming. But does the recent uptick mean that we have entered a period of global cooling? NSIDC scientists point out why we shouldn’t be reading too much into one summer of less sea ice decline. Continue reading

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?

Continue reading

Are we in a snow drought?

The central and southwestern portions of the United States have experienced drought for the past several years. This photograph was taken in mid-February, 2010. By that point in winter, these rows would normally have been fully covered in snow. Photograph credit: Kristy Johnson (http://www.flickr.com/photos/kayaker1204/4359744393/)

In spite of the massive blizzards that have slammed parts of the northeastern United States, much of the country is experiencing a pronounced lack of snow. And where there is snow, it is less than usual. It follows a very low snow year from the previous season, causing people to worry if low snowfall is the new normal.

A previous Icelights post, Arctic sea ice and U.S. weather, discussed possible causes behind the changes in winter weather, trying to see if there are correlations to larger climate changes. Researchers like Jennifer Francis of Rutgers University are exploring the possibility that declining sea ice in the Arctic is altering atmospheric temperatures and weakening the jet stream. This change may shift the Northern Hemisphere storm track, leaving some places unusually snowy, or leaving normally snowy locations dry. Can a few good blizzards help reverse the snow drought across parts of the United States? Or is this string of dry winters yet another symptom of climate change? Continue reading