Global air circulation Notes for Grade 12

Global air circulation Notes for Grade 12 with Questions and Answers: Did you know that global air circulation winds cover large areas over the Earth’s surface? Global air circulation are also referred to as planetary winds.

Winds related to global air circulation

There are three global wind systems that are related to the global circulation:

• The tropical easterlies
• The westerlies
• The polar easterlies

What causes the circulation of air in the atmosphere

A force called Coriolis force causes global winds to move to the left in the southern hemisphere and to the right in the northern hemisphere. The tri-cellular arrangement, the pressure belts and the global winds together form the global air circulation.

The global air circulation diagram

Below is the global air circulation diagram

What are the 3 types of atmospheric circulation cells called?

The 3 types of atmospheric circulation cells called:

• Polar cell – The smallest and weakest cells are the Polar cells, which extend from between 60 and 70 degrees north and south, to the poles.
• Ferrel cell – Ferrel cell refers to a model that belongs to the mid-latitude region of the Earth’s wind flow
• Hadley cell – low-latitude overturning circulations that have air rising at the equator and air sinking at roughly 30° latitude.

Sources

https://www.metoffice.gov.uk/weather/learn-about/weather/atmosphere/global-circulation-patterns#:~:text=over%20the%20UK.-,Polar%20cell,lower%20latitudes%20at%20the%20surface.

https://groups.seas.harvard.edu/climate/eli/research/equable/hadley.html#:~:text=Hadley%20Cells%20are%20the%20low,control%20low%2Dlatitude%20weather%20patterns.