These polar vortex stretches are happening more frequently as the world — and especially the Arctic — warms, a 2021 paper published in the journal Science, also co-authored by Cohen, demonstrated.

The polar vortex is usually “like an aircraft carrier, it doesn’t turn around quickly and isn’t very nimble,” Cohen said. “I’ve really never seen anything like it.” ...

One way to track the polar vortex is through potential vorticity, which describes the amount of rotational energy, or "spin," in a parcel of air. This animation shows daily potential vorticity in ...

These polar vortex stretches are happening more frequently as the world — and especially the Arctic — warms, a 2021 paper published in the journal Science, also co-authored by Cohen, demonstrated.

The polar vortex has taken on an unexpected pattern this winter — one that’s made part of the United States the most unusually cold place on the planet, at least so far this year.