concept

Orographic lift

Air forced upward by the shape of the land itself: wind meeting a mountain flank or a cliff cannot go through it and must climb, so an enormous mass of air is lifted for no reason other than terrain. For soaring animals and for human gliders this is the most dependable gift in the sky — the updraft hugs the slope and is there all day as long as the wind blows, unlike thermals, which only appear once the ground has heated. The price is rain: climbing air cools, its vapour condenses, and the windward slope stays drenched while the far side goes dry.