A U.S. climatologist says earth would be better off if the Arctic was declared a no-fly zone. From CBC News :
In a new report, Mark Jacobson, a professor of civil engineering at Stanford University in California, says black soot from commercial jets is attracting heat from the sun.... More than 50,000 planes fly through the Arctic Circle every year. Jacobson says that could be a major cause of Arctic melting.
And a researcher at Ohio State University says dark soot from Arctic tundra fires could be responsible for the decrease in reflectivity of the Greenland ice cap. From Phys.org :
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.