Transcript AIR PRESSURE

Chapter 18
Test 5 material
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AIR EXERTS A FORCE ON THE SURFACE OF
OBJECTS THAT IT CONTACTS.
AIR PRESSURE IS A MEASURE OF THAT FORCE
PER UNIT OF SURFACE AREA
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WITH FEWER AIR MOLECULES IN THE UPPER
ATMOSPHERE, THE PRESSURE DECREASES AS
WE RISE IN THE ATMOSPHERE
IT DECREASES AT AN INCREASING RATE
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MOUNTAIN SICKNESS
DIZZY
HEADACHE
SHORTNESS OF BREATH
RED BLOOD CELL COUNT NEEDS TO INCREASE
THINK CUBS WILL WIN IT ALL
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AIR PRESSURE DIFFERS FROM ONE PLACE TO
ANOTHER AND THESE MIGHT NOT BE FROM
ELEVATION DIFFERENCES ALONE
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HUGE VOLUME OF AIR THAT IS RELATIVELY
UNIFORM IN TEMPERATURE, DENSITY, AND
WATER VAPOR CONTENT
AS AIR MASS MOVES ACROSS THE EARTH’S
SURFACE THE PRESSURE FALLS OR RISES
BASED UPON QUALITY OF THE AIR MASS
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RISING PRESSURE = IMPROVING WEATHER
FALLING PRESSURE = STORM Y WEATHER
STEADY PRESSURE = WEATHER STAYS THE
SAME
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COLD OR WARM AIR?
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DRY OR MOIST AIR?
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WHEN MOISTURE IS ADDED TO THE AIR, A
HEAVIER GAS IS REPLACED BY THE WATER
VAPOR SO MOIST AIR IS LIGHTER THAN DRY
AIR
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DIVERGENCE OF AIR
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ANTICYCLONE
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CONVERGANCE OF AIR
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CYCLONE
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MILLIBARS = 1014 MB AT SEA LEVEL
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INCHES = 29.92 INCHES AT SEA LEVEL
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BAROMETER - MERCURY OR ANEROID (
LEGENDS ON THE DIAL)
BAROGRAPH
ALTIMETER
◦ Chapter 18
◦ Test 5 Material
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PRESSURE GRADIENTS
CORIOLIS EFFECT
FRICTION
CENTRIPETAL AND CENTRIFUGAL FORCE
GRAVITY
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A GRADIENT IS SIMPLY A CHANGE IN SOME
PROPERTY WITH DISTANCE. PRESSURE
GRADIENT IS DIFFERENCE IN AIR PRESSURE
FROM ONE PLACE TO ANOTHER.
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A GRADIENT IS SIMPLY A CHANGE IN SOME
PROPERTY WITH DISTANCE. PRESSURE
GRADIENT IS DIFFERENCE IN AIR PRESSURE
FROM ONE PLACE TO ANOTHER.
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AN ISOBAR IS A LINE THAT CONNECTS POINTS
OF EQUAL AIR PRESSURE.
WHEN ISOBARS ARE CLOSELY SPACED, WE
HAVE A STRONG PRESSURE GRADIENT AND
HIGH WINDS.
WHEN THE ISOBARS ARE FAR APART, THE
GRADIENT IS WEAK AND WINDS ARE LIGHT.
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EARTH’S ROTATION IS RESPONSIBLE FOR THE
CORIOLIS EFFECT WHICH IS A DEFLECTION OF
THE WINDS.
IN THE NORTHERN HEMISPHERE, WINDS ARE
DEFLECTED TO THE RIGHT;
IN THE SOUTHERN HEMISPHERE TO THE LEFT.
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AN INWARD PULLING FORCE
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AN OUTWARD PULLING FORCE
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CENTRIPETAL AND CENTRIFUGAL FORCE
TOGETHER PRODUCE A CIRCULAR PATTERN
OF WINDS AROUND HIGH AND LOW PRESSURE
SYSTEMS