A katabatic wind, from the Greek word katabatikos meaning "going downhill", is a wind that blows down a topographic incline such as a hill, mountain, or glacier.
The cold form of katabatic wind originates in a cooling, either radiatively or through vertical motion, of air at the top of the mountain, glacier, or hill. Since the density of air increases with lower temperature, the air will flow downwards, warming adiabatically as it descends, but still remaining relatively cold.
Cold katabatic winds are frequently found in the early hours of the night when the solar heating has ceased and the ground cools by emitting infrared radiation. Cold air from extratropical cyclones may contribute to this effect.
Such winds, particularly when they occur over a wide area, are sometimes called fall winds.EP and buttons available via myspace or [email protected]
