Dirty snow a culprit in Arctic warming?
snow in the Arctic
Photo:
Carol Walker
Research suggests that dirty snow is warming the Arctic, and could have consequences for our global climate.
Airborne particles – soot from industrial smokestacks, car exhaust, dust and forest fires – can darken Arctic snow. Darker snow causes it to absorb sunlight.
It’s the same as when you wear a dark shirt on a sunny day. Many studies point to greenhouse gas emissions as the cause of Earth’s warming climate over the past two centuries.
Charlie Zender: Surprisingly, dirty snow plays a role comparable to the role of greenhouse gases in causing polar climate warming.
That’s Charlie Zender of the University of California, co-author of the darkened snow study, published in June 2007. The study indicated that up to 19% of Earth’s total warming over the past two centuries could be caused by darkened snow. And Zender’s worried that darker snow is causing glaciers and sea ice to retreat.
Zender: And when those glaciers or summer sea ice cover disappear they reveal darker land underneath which causes a very strong climate response.
Our thanks today to NASA: explore, discover, understand.
Our thanks to:
Charlie Zender
Associate Professor of Earth System Science
University of California
