(2)
Each hemisphere has three basic wind systems. The first, at 30( latitude north and south,
is known as the (3).
There, air sinks, warms, and moves toward the
equator from northeast to southwest in the northern hemisphere and from southeast to
northwest in the southern hemisphere. When the air reaches the equator, it rises, then moves
back toward 30( to start the cycle again. These winds from both hemispheres converge at the
equator. They are forced upward, creating an area of (4)
This area
near the equator is called the (5).
The second wind system, called the (6)
flows between 300 and
60 Latitude north and south of the equator. Its circulation pattern is opposite that of the
wind system discussed above. These winds are responsible for the movement of many
weather systems across much of (7)
The third wind system, the (8).
Latitude. In the northern hemisphere, these winds flow from the (9)
to the (10)
lies between the poles and 60(
They flow in the opposite direction in the southern
hemisphere.
Narrow bands of fast, high-altitude, westerly winds called (11)
flow at the boundaries between wind zones in the middle latitudes. These bands of
wind steer weather systems in the middle latitudes. The most important one, the
(12)
separates the polar easterlies from the prevailing westerlies.