Wind

Synonyms

Breeze; Draft; Gale; Gust; Velocity; Whirlwind

Definition

Wind in its simplest form is the movement of air flow within Earth’s atmosphere. The Greek word for wind is anemos.

Basics of Wind

Wind exists because of gradients in atmospheric pressure that arise from differential heating between lower and higher latitudes. In an inertial (nonaccelerating) frame of reference, motion of air can be explained by Newton’s second law of motion, which states that the acceleration of an object depends directly upon the resultant force acting upon the object and inversely upon the mass of the object (Wallace and Hobbs 2006).

There are several apparent and real forces that act together on molecules of air to generate wind. Starting from ground level, when a fluid is in an equilibrium state, atmospheric pressure decreases with increasing altitude. There is a net upward force due to pressure decreasing with increasing height (i.e., the pressure gradient force) as well as a net downward force...