What are global atmospheric circulations and how do they occur in the atmosphere of the planet Earth?
as you know :
Global atmospheric circulation is the movement of air around the planet. It explains how thermal energy and storm systems move over the Earth's surface.
Without the rotation of the earth, the tilt of the sun and the surface waters, global circulation would be simple. With the sun directly over the equator, the Earth and atmosphere there heat up more than the rest of the planet. This area gets very hot and warm air rises to the atmosphere. This creates a stable belt of low pressure around the equator. That warm air then moves directly north toward the poles, where it cools and sinks, creating a large area of high pressure. The difference in temperature and pressure pushes cold air back south to the equator (top right), creating a simple global circulation.
However, the Earth's tilt means that the Sun is not always directly above the equator, and so the exact location where the most solar radiation is received is constantly changing. The rotation of the Earth causes the air to move eastward, which is called the Coriolis effect (this is explained in more detail in the next section, the jet stream). The uneven distribution of land and water across the globe further disrupts the uniformity of air movement, with larger amounts of land in the Northern Hemisphere creating semi-permanent lows and highs. As a result, the actual global pattern of atmospheric circulation is much more complex than a direct flow between the equator and the poles.
Hadley Cell - At low latitudes, air moves toward the equator, where it warms and rises vertically. In the upper atmosphere, the air moves towards the pole. It forms a convective cell covering tropical and subtropical climates. This cell is named after the English physicist and meteorologist George Hadley, who in 1735 proposed a single blood circulation for each hemisphere.
Ferrell Cell - In this mid-latitude atmospheric circulation cell, near-surface air flows poleward and eastward, while air higher in the atmosphere moves equatorward and westward. These winds, proposed by William Ferrell in 1856, were the first to account for the westerly winds between 35 and 60 degrees north-east, which are caused by friction, not the heat difference between the equator and the poles.
Polar cell - At higher latitudes, air rises and moves toward the poles. When over the poles, the air sinks and forms areas of high atmospheric pressure called polar highs. At the surface, air moves outward from the polar highs, creating an easterly surface wind called the polar easterly. It is the smallest and weakest cell.
rotation of the earth
Due to the Earth's rotation, there are three main circulations between the equator and the poles.
These cells describe the circulation in both the Northern and Southern Hemispheres, although differences in land masses result in varying degrees of uniformity.
Between each of these circulating cells are surface bands of high and low pressure. The high pressure belt is located at about 30 degrees northeast latitude and at each pole. Low pressure bands are found at the equator and 50-60 degrees north east.
Dry and warm weather is usually associated with high pressure, while rainy and stormy weather is associated with low pressure. You can see the results of these rotations on a globe. Look at the number of deserts located along 30°N latitude around the world (including the American Southwest and Mexico, North Africa, and Australia). Then look at the area between 50° and 60° N latitude (including Canada, Alaska, the British Isles, and Russia in the Northern Hemisphere). These latitudes, especially on the western coasts of the continents, tend to have more precipitation due to the movement of more storms around the Earth.
Abbas,
You seem to have answered your own question - was there a reason to post this?
Dear James Garry
Certified Physicist, Ph.D Design and Development Manager at Red Core Consulting ltd.
Vancouver, Canada
Hello dear teacher, thank you for your kind reminder. I just wanted to know your opinion and maybe my scientific knowledge is not enough and I wanted to benefit scientifically from your existence. I am sorry that I wrote your name wrong and this was due to Google translation and it was not my intention. God willing, I will be able to take advantage of your existence, dear professor. thank you . Thank you Abbas