Wind and Moisture Belts:

This is the 'Planetary Wind and Moisture Belts' graphic from page 14 of the ESRT. There seems to be very many things going on all at once and it looks extremely complicated. But if we dissect it into separate parts then each piece should be easier to understand.

Both of these frames (right)show the wind belts in the northern hemisphere. Notice that if you look in the direction that the winds are blowing, they curve to the right. This is because of Coriolis forces caused by the Earth's rotation.

Northern Hemisphere = Right

These frames (left) show the wind belts in the southern hemisphere. If you look in the direction that the winds are blowing, they curve to the left. Again, this shift in direction is due to the Coriolis effect caused by Earth's rotation.

Southern Hemisphere = Left

The arrows here (right) show the movement of air in the troposphere. This is what happens:
> The insolation on the equator (blue zone) is intense which is why the equator is hot. The air near the surface (A) is heated by the warm earth and as the heated air expands and becomes less dense, it rises.
> As the air rises towards location B it cools to the dew point and it rains. It rains almost every day on the equator which is why the blue zone is wet. This process removes almost all the moisture from the air which is now very dry.
> As the dry air descends from B to C it warms and reaches the Earth's surface in two regions (orange zones) at 30N and 30S of the equator. These regions are very warm and dry and many of the world's great deserts are found there.  

You should recognize this kind of movement. It is a  classic convection current.

The same kinds of convection currents are occurring at the poles. Here (relatively) warm air at location(s) A is rising. As it rises towards location B, it cools and reaches the dew point. Water vapor in the air condenses and it rains which leaves the air very dry and cool. This cool, dry, very dense air located at C begins to sink towards the poles.

Both poles, north and south, are classified as deserts. They receive very little moisture but since what does fall remains frozen (especially at the south pole) it piles up year after year creating ice shelves and glaciers.

Jet streams are high speed air currents flowing west to east around the planet. They are found at the tropopause. These currents meander north and south bringing warm or cold air masses with them.

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