Where there is more evapuration, the air rises in the form of convectional currents.
Convection currents transfer heat from one place to another by mass motion of a fluid such as water, air or molten rock. The heat transfer function of convection currents drives the earth’s ocean currents, atmospheric weather and geology. Convection is different from conduction, which is a transfer of heat between substances in direct contact with each other.
TL;DR (Too Long; Didn't Read)
Convection currents rely on the constant cyclical motion of air, water and other substances to distribute heat. As heated air rises, for example, it pulls cooler air into its place -- where it can be heated, rise, and pull in more cool air.
How Convection Works
Convection currents form because a heated fluid expands, becoming less dense. The less-dense heated fluid rises away from the heat source. As it rises, it pulls cooler fluid down to replace it. This fluid in turn is heated, rises and pulls down more cool fluid. This cycle establishes a circular current that stops only when heat is evenly distributed throughout the fluid. For instance, a hot radiator heats the air immediately around it. The air rises toward the ceiling, pulling cooler air down from the ceiling into the radiator to be heated. This process repeats until the air in the room is evenly heated.
Ocean Convection
Convection drives the Gulf Stream and other currents that turn over and mix up the waters in the world’s oceans. Cold polar water is drawn down from higher latitudes and sinks to the ocean bottom, pulled down toward the equator as lighter, warmer water rises to the ocean’s surface. The warmer water is pulled northward to replace the cold water that’s been pulled southward. This process distributes heat and soluble nutrients around the world.