The moving air in the atmosphere is called wind. The movement of air is caused due to the changes in temperature. When the temperature of air increases, it expands. This expansion makes the air lighter and the air rises. As the warm air rises, the empty place is filled by cooler air. This continuous movement of air is wind. The larger the differences in temperature, the more varying the wind speeds are. Mostly the wind flow originates from the equator to the Poles as the equator receives maximum heat.
Wind Direction: The direction in which the wind blows is called wind direction. For example, wind blowing from east to west is called easterly wind, while that blowing from west to east is westerly wind. The direction in which the wind flows affects the climate on daily basis. For example, if the wind blows from a warm place, it will be hot and if it blows from a cold place, it will be cool. The direction of the wind is measured with respect to the compass reading, which is in terms of 360° on the compass (North). The common types of wind observed across the planet are: polar high, polar easterlies, polar front, westerlies, horse latitudes, trade winds and doldrums.
