General Circulation of the Atmosphere| Class 11 Geography Notes

The General Circulation of the Atmosphere is a pattern that says about the wind movements across the Earth or a certain planet. In 1735; English meteorologist George Hadley proposed his modern theory based on the trade winds. The core idea of the General Circulation of the Atmosphere is that the circulation takes place majorly in the equatorial regions where the air density is relatively low. The warm air moves towards the Earth’s poles where it becomes cold and comes back to the equator again. The process is based on different factors like Pressure belts, ITCZ migration, and rotation of the Earth. Hadley cells are the global level scales that push the warm air to high altitudes and maintain the circulation of the Atmosphere.

In this article, we are going to discuss the General Circulation of the Atmosphere in detail.

The General Circulation of the Atmosphere

The General Circulation of the Atmosphere gives a proper explanation of how the thermal energy and storm system moves on the Earth’s surface. It also determines the regional patterns that are based on or affected by different factors like Pressure belts, ITCZ migration, and rotation of the Earth.

Here are the major factors that may effect The General Circulation of the Atmosphere as mentioned below.

Atmospheric Heating

Atmospheric heating tells about the variation of the heating process at different latitudes on the Earth. The heating process of the atmosphere is uneven. The heat makes the air warm and it rises upwards. This process creates a low pressure.

Pressure Belts

The pressure belts are the atmospheric circulation cells that are created due to the variation in heating. These belts play a major role in shaping the world’s weather patterns.

ITCZ Migration

The migration of the Inter-Tropical Convergence Zone (ITCZ) is another factor in the circulation of the atmosphere. Along with the apparent path of the sun, these zones create low pressure due to high insolation.

Earth’s Rotation

The Earth’s rotation changes the flow pattern and the path of hot air. It also affects the trade winds along the surface of the planet. This all happens due to the Coriolis effect.

Types Of General Circulation of the Atmosphere

There are two major types of the General circulation of the atmosphere including Latitudinal Atmospheric Circulation and Longitudinal Atmospheric Circulation. Let’s discuss.

Latitudinal Atmospheric Circulation

Latitudinal Atmospheric Circulation happens due to the uneven heating of the Earth and its surroundings. In the tropic region, Earth absorbs much solar radiation. After this, the tropic region transfers the heat to the latitude areas where the intensity is much more lower.

Longitudinal Atmospheric Circulation

Longitudinal Atmospheric Circulation happens due to the difference between the ocean’s temperature and the surface temperature. In this, water absorbs more heat than the water body. But the problem is, the temperature of the water body does not increase as same as the land. In the Longitudinal Atmospheric Circulation, the wind moves from the east side to the west side.

Difference Between Latitudinal Atmospheric Circulation and Longitudinal Atmospheric Circulation

Here are the major difference between Latitudinal Atmospheric Circulation and Longitudinal Atmospheric Circulation as mentioned below.

Aspect	Latitudinal Circulation	Longitudinal Circulation
Driving Force	Driven by differences in sunlight on Earth’s surface.	Driven by the changes in ocean temperatures, especially in the Pacific.
Heating Variation	Sunlight creates temperature differences across latitudes.	Ocean heat absorption evens out temperature variations.
Cell Structure	Creates specific wind patterns and pressure systems.	Lacks distinct pattern. It is characterized by events like El Niño.
Geographical Focus	Seen globally in Earth’s atmosphere.	Mainly affects weather in specific areas, especially the Pacific region.
Impact on Weather	Influences seasonal changes consistently.	Leads to sudden, local weather changes, especially during El Niño.
Forecasting Utility	Used for long-term weather predictions.	Used for short-term predictions, especially during El Niño events.

FAQs – Class 11 General Circulation of the Atmosphere

What is generalized circulation of the atmosphere?

The general circulation of the atmosphere. Hot air rises in the tropics, moves north or south, descends and returns in the equatorial “Hadley cells”. Its path along the surface is bent into the trade winds by the Earth’s rotation (Coriolis Effect). Two other cells in each hemisphere work similarly.

What is the general circulation model of the atmosphere?

General circulation models (GCMs) are mathematical models capable of representing physical processes of the atmosphere and ocean to simulate response of global climate to the increasing greenhouse gas emission (IPCC, 2013).

What are the general directions of atmospheric circulation?

As the air at the surface moves toward the equator, it deviates westwards, again as a result of the Coriolis effect. The air flows at the surface are called the polar easterlies, flowing from northeast to southwest near the north pole and from southeast to northwest near the south pole.

What causes general circulation of the atmosphere?

Atmospheric circulation happens because of the Earth’s surface is unevenly heated, there are big differences in air temperature from the equator to the poles and over different types of terrain. These temperature differences are what cause convection in the atmospheric and air to circulate over the globe.

What are the 3 types of atmospheric circulation called?

In each hemisphere there are three cells including Hadley cell, Ferrel cell and Polar cell in which air circulates through the entire depth of the troposphere.