Cloud Atlas
The high Arctic is dangerous in the dark of winter. Temperatures drop to–40 degrees. Ice cracks underfoot. Polar bears roam. Yet scientists on the Alfred Wegener Institute’s MOSAiC expedition braved these hazards so they could study the Arctic atmosphere for a full year. They have urgent questions about why the region is warming faster than elsewhere on Earth, and clouds may be key. “Clouds are one of the leading sources of uncertainty in our models,” says expedition co-coordinator Matthew Shupe with the University of Colorado and NOAA. So in October 2019 the Polarstern icebreaker was locked into the frozen ocean near the North Pole and left to drift as scientists sampled the sea, ice, and atmosphere. The data will yield insights into the Arctic’s cloud cycle and a sharper picture…