Chapter 19: Air Pressure and Wind
Air Pressure Defined
Air pressure is ______________________________________________________________________________
Air pressure is exerted in _____________________________________________________________________
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Measuring Air Pressure
A ____________________ is a device used for measuring air pressure.
When air pressure ____________________, the mercury in the tube ____________________. When air
pressure ____________________, so does the height of the mercury column.
Factors Affecting Wind
Wind is the result of _____________________________________________ in air pressure. Air flows from
areas of _________________________ to areas of _________________________.
The unequal heading of Earth’s surface generates pressure differences. _______________________________
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Three factors combine to control wind: __________________________________________________________
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Pressure Differences
A _________________________ is the amount of pressure change occurring over a given distance.
Closely spaced isobars - ______________________________________________________________________
- indicate a steep pressure gradient and high winds. Widely spaced isobars indicate a weak pressure gradient
and light winds.
The Coriolis effect ___________________________________________________________________________
In the Northern Hemisphere, all free-moving objects or fluids, including the wind, are deflected to the
____________________ of their path of motion. In the Southern Hemisphere, they are deflected to the
____________________.
Highs and Lows
Cyclones are centers of ______________________________________
Anticyclones are centers of ___________________________________
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Cyclonic and Anticyclonic Winds
When the pressure gradient and the Coriolis effect are applied to pressure centers in the Northern Hemisphere,
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Weather and Air Pressure
Rising air is associated with __________________________________________________________, where as sinking air
produces ________________________________________
Weather Forecasting
Weather reports emphasize the locations and possible paths of cyclones and anticyclones.
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Local Winds
The local winds are caused either by ____________________________________________________________________
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Sea and Land Breezes
__________________________________________________________________________________________
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Valley and Mountain Breezes
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How Wind Is Measured
Wind Direction
The ___________________________________ is the wind that blows more often from one direction than
from any other.
In the United States, the _________________________ consistently move weather from west to east across
the continent.
An anemometer is __________________________________________________________________________
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