Our quickly warming world is losing many signs of winter—once snowy mountain tops aren’t as frosty tipped, glaciers are disappearing, and sea ice at the poles is melting at alarming rates. But new research outlines a small reason for optimism. Scientists project that even though climate change will make the world hotter, snow may actually become brighter and whiter.
“There’s clean snow and there’s dirty snow, and how they respond to sunlight is very different.” Pollution particles settle on top of the snowpack, making it darker. Darker snow absorbs sunlight, which makes snow melt faster. Cleaner snow is whiter and reflects sunlight back into space, helping regulate temperatures and maintain the snowpack for longer during the winter. Clean snowmelt is also important for the many people who rely on snowmelt to replenish waterways that supply drinking water.