Evaporation mechanism Evaporation by natural convection:

The thin layer of air in contact with the water surface quickly becoming saturated with water vapor, due to the movement of water molecules in the air at the interface, is then lighter. It moves upward carrying the water vapor with it.This movement is compensated by a movement in direction. reverse (down) by the drier ambient air, therefore also heavier and which takes its place. perpetually. If there is no air current at all the evaporation thus occurring by molecular diffusion is a very slow process. It is evaporation by natural convection.

Evaporation by forced convection:

If there is air movement on the surface the displacement of the thin saturated air layer is accelerated by it. The thin air layer is replaced by drier ambient air which is quickly saturated again The process continues and evaporation takes place rapidly Air movement can be caused by:
-The ventilation system for an indoor swimming pool
-By the wind for an outdoor pool.