Question

What is the main cause of wind movement?

Answer 1

There are two main reasons for the movement of wind:

1. Uneven heating of land and water:

• During the day, land heats up faster than water. This causes the air above land to be warmer than the air above water.
• As hot air from the land rises up as it is lighter and less dense, colder and denser air from the oceans and seas moves towards the land. This is known as sea breeze.
• During the night, land cools down faster than water. This causes air above water to be warmer than air above land.
• So hot air from the water rises up, and cold air from the land moves towards the water. This is known as land breeze.

2. Unequal heating between the equator and the poles:

• Regions near the equator get maximum heat from the Sun whereas regions near the poles don't get much heat.
• Therefore, regions near the equator are much warmer than those closer to the poles.
• This warm air rises, and the cooler air from the regions in the 0-30 degrees latitude belt on either side of the equator moves in.
• The winds blow from the North and the South towards the equator.
• At the poles, the air is colder than that at latitudes about 60 degrees. The warm air at these latitudes rises up and the cold wind from the polar regions rushes in, to take its place.
• Thus, wind circulation is set up from the poles to the warmer latitudes.