But bright surfaces, such as sea ice or snow, reflect as much as 88 percent of that light back into the atmosphere, experts say.
When the surface is obscured by clouds, sunlight is blocked, cooling the region underneath.
In recent years sea ice has been retreating and snow is melting earlier each year across much of the Arctic, which means that more dark surfaces become exposed to the sun, Stone explained.
"But then you bring in the smoke and it [absorbs more] over those dark surfaces. This represents a negative feedback in a warming world," he said.
Another factor to consider is the so-called dirty snow effect, according to Alan Robock of Rutgers University.
Ice and snow will become darker and melt faster if smoke particles settle on those surfaces.
"So it's not clear that the effects of the smoke are good anyway, as people and animals breathe the smoke. And the net effects on the climate system are still not well quantified," said Robock, who was not involved in the study.
Additionally, it's important to note that smoke absorbs sunlight to warm the atmosphere.
"If the atmosphere is heated by the aerosols, some of that energy also heats the surface," Robock said.
Carbon Dioxide Impact
The study authors did not quantify carbon dioxide—a leading greenhouse gas—released as a result of the fires.
"There is probably some counterbalance," study author Stone said. "The aerosol [from smoke] has a very significant short-term effect on the region where smoke is dispersed, while emitted [carbon dioxide] is more widely dispersed over time and can persist for years."
Carbon dioxide most likely has a negligible short-term effect in the Arctic, he added.
Rutgers' Robock agrees.
"This was carbon that was taken out of the atmosphere when the trees grew, and so if forests are in balance there's no net effect on carbon dioxide."
"After the fires burn there will be more trees growing there taking the [carbon dioxide] back out of the atmosphere," he said. "So that's not really a concern."
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