What exactly is wind and where does it come from?

Answer 1

Wind is air in motion. Air moves because it reacts to a force. Most of the time the force is caused by differences in air pressure over the territory the air resides. These differences can be as small as unequal heating along a seashore resulting in differences in surface air pressure resulting in sea breezes, unequal heating along a mountain slope causing warm air to rise and causing mountain breezes or as large as large as continents. An example of the latter is the monsoon winds of Asia where differences in air pressure over Asia and the western oceans causes the air to move. In between are the differences in air pressure between high pressure systems and low pressure systems (storms). In all cases, air moves (wind) from higher pressures to lower pressures.

Another force that causes air to move is gravity. This is best illustrated when air is cooled by water evaporating in it as happens during rain showers and thunderstorms. As the air cools, it becomes heavier than the surrounding air and sinks. It picks up speed until it hits the ground and spreads out causing gustiness. Another example of gravity causing wind is along the lee of mountain ranges. When conditions are right, gravity waves set up causing the higher velocity wind at higher altitude to descend to the surface causing damage.

As you can tell, there are many causes of wind. But the one common cause is a force acting on the air to set it in motion.

Answer 2

This is very simplified, but wind is caused by many different reasons, all of which have been already stated, however the main reason for strong winds is the difference in atmospheric pressure. The simplest way I can describe this is by thinking about when you open a door and all of sudden you feel a breeze. This is the air flowing from the higher pressure area in the building to the lower pressure outside or vise a versa, depending on conditions.

Answer 3

In a very simple form, wind is the result of uneven heating of the earths surface. Different surfaces heat at different rates, the oceans not as much as dark forest. High pressure and low pressure are all the result of this basic fact. Warm air rises (low pressure) and cold air sinks (high pressure). Wind is the result of air moving between hign and low pressure and areas of uneven heating.

Answer 4

Wind is caused by differing pressure between air masses. Air will move from areas of higher pressure to areas of lower pressure.

Answer 5

To put it simply, it is simply a difference between higher and lower pressures. To put it in easier terms: http://simple.wikipedia.org/wiki/Wind

Answer 6

Pressure differences or, in the case of storms, air hitting the ground and spreading out.