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CHAPTER VI

THE AIR: MAJOR CIRCULATION: LOCAL WINDS

The convectional or vertical movements of the air have been mentioned incidentally as affecting the diffusion of warmth. They are considered in detail in succeeding chapters. The horizontal movements constitute the winds. So far as human

Redway’s Physical Geography.

General movements of the atmosphere.

activities are concerned, the general horizontal movements consist of a broad tropical belt of easterly winds flanked on the north and on the south by a broad belt of westerly winds. The three belts move northward with the apparent motion of the sun northward in June, and southward in December. The yearly oscillation covers about 120 degrees of latitude, a total of about 7200 nautical miles.

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