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b. The form of circulation that would occur in theory (as shown in figure 1) is greatly modified

by many forces, one being the rotation of the earth. In the northern hemisphere, this rotation causes

air to In the southern hemisphere, air flow to the right of its normal path. This action caused by the
earth's flows to the left of its normal path. We will only rotation is called the Coriolis force. talk about

the movement of the air in the northern hemisphere.

C. As the air rises and moves northward from the equator, it is deflected toward the east, and
by the time it has traveled about a third of the distance to the pole it is no longer moving northward,

but eastward. This causes the air to accumulate in a belt and creates an area of high pressure. Some

of this air is then forced down to the th's surface, where part flows southward, returning to th
and part flows northward along the surface. The remaining portion of s air aloft continues its journey

northward. As it moves it is cooled, and finally descends near the pole, where it begins a return trip to

the equator. Before it moves very far southward it comes conflict with the warmer air, that had
descended in the fi and flowed northward on the surface. The warmer air moves up over the

air and continues northward, producing an accumulation hemisphere. the northern part of the As it

becomes cooled and denser, it flows southward.

The general circulation. The Coriolis force deflects high level winds from the south to the east. Low

level north Between winds from the pole are deflected to the west. these two movements is a large

mixing zone. The warm air masses slide over the cold air masses as t they migrate between the equator
and the poles.

Figure 2