'Arctic wildfires increasing Greenland melting'

Researchers presented images from NASA's Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite, which captured smoke from Arctic fires billowing out over Greenland during the summer of 2012.

Jason Box, associate professor of geography at Ohio State, said that researchers have long been concerned with how the Greenland landscape is losing its sparkly reflective quality as temperatures rise.

The surface is darkening as ice melts away, and, since dark surfaces are less reflective than light ones, the surface captures more heat, which leads to stronger and more prolonged melting.

Researchers previously recorded a 6 per cent drop in reflectivity in Greenland over the last decade, which Box calculates will cause enough warming to bring the entire surface of the ice sheet to melting each summer, as it did in 2012.

But along with the melting, researchers believe that there is a second environmental effect that is darkening polar ice: soot from wildfires, which may be becoming more common in the Arctic.

"Soot is an extremely powerful light absorber. It settles over the ice and captures the Sun's heat. That's why increasing tundra wildfires have the potential to accelerate the melting in Greenland," Box said.

Box was inspired to investigate tundra fires after his home state of Colorado suffered devastating wildfires this past year. According to officials, those fires were driven in part by high temperatures.

To find evidence of soot deposition from these fires, Box and his team first used thermal images from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) to identify large fires in the region.

Then they used computer models to project possible smoke particle trajectories, which suggested that the smoke from various fires could indeed reach Greenland.

Finally, they used that information to examine the CALIPSO data, and pinpoint sooty aerosols