Translations:AY Honors/Weather/Answer Key/83/en
From Pathfinder Wiki
A rising body of air typically loses heat because it radiates heat. At some point the air becomes denser than the air underneath it, which is still rising. Since it cannot descend through the rising air, it moves to one side. At some distance its downward force overcomes the rising force beneath it and the air begins to descend. As it descends, it warms again through surface contact, conductivity, or compression, and the cycle repeats itself. (The heating through compression of descending air is what is responsible for such welcome winter phenomena as what is known in Western North America as a Chinook wind or in the Alps as a Föhn wind.)