Both polar vortexes are present year-round, but they weaken in the summer and strengthen in the winter, governed by rising and falling seasonal temperatures. South of the Arctic’s polar vortex ...

The National Weather Service (NWS) has issued winter storm warnings as a powerful polar vortex is set to drop ... lulls ...

(See "Cold Fires Up Arctic Adventurer," fall 2007.) Amundsen is one of my heroes. In many ways he embodied the self-critical, humble approach of living with nature that has made Norway the world ...