Katabatic winds
From open-encyclopedia.com - the free encyclopedia.
A katabatic wind is a wind blowing down a gradient caused by buoyancy forces - ie the air is cool. Over the major Ice sheets of Antarctica and Greenland katabatic winds blow with great constancy particularly during the polar night, when heat loss by radiation from the surface cools the overlying air.
On a smaller scale, katabatic winds blow in mountain valleys.
