Download 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
Washington, IL tornado 11/17/13
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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 = STORMY 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 /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
LAND BREEZE***
OCCURS AS A LOW PRESSURE
SYSTEM DEVELOPS OVER WATER
AT NIGHT DUE TO SPECIFIC HEAT
DIFFERENCES. GOES FROM THE
LAND OUT TO THE WATER
SEA BREEZE*
OCCURS AS LOW PRESSURE AREA
DEVELOPS OVER LAND DURING
HEAT OF DAY. AIR FLOWS FROM
OCEAN TO LAND BRINGING IN
COOLING WINDS.
KATABATIC WIND
COLD DRY MOUNTAIN WIND
ALSO KNOWN AS MISTRAL & BORA
CAN CAUSE EXTREMELY COLD
TEMPERATURES IN A RELATIVELY
SHORT PERIOD OF TIME.
CHINOOK WINDS
WARM AND DRY MOUNTAIN WIND
BRINGING RAPID TEMPERATURE
INCREASES
ALSO KNOWN AS ZONDA, FOEHN, &
SANTA ANA
MONSOON*
SEASONAL REVERSAL OF WIND
DRY MONSOON OCCURS IN WINTER
WITH LOW PRESSURE OVER
WATER
WET MONSOON OCCURS IN
SUMMER WITH LOW PRESSURE
OVER LAND
AIR MASSES & FRONTS
Chapter 19
AIR MASS
A LARGE BODY OF AIR THAT IS
CHARACTERIZED BY THE
SAMENESS OF TEMPERATURE &
HUMIDITY
SOURCE REGION******
THE AREA WHERE AN AIR MASS
ACQUIRES ITS PROPERTIES OF
TEMPERATURE AND MOISTURE
CONTINENTAL – LAND [DRY]
MARITIME OR MARINE – WATER
[MOIST]
AIR MASSES*********
FRONTS********
BOUNDARIES THAT SEPARATE AIR
MASSES OF DIFFERENT DENSITIES
WARM – OVER RUNNING
COLD
OCCLUDED - PINCHING
STATIONARY
WARM FRONT
COLD FRONT
OCCLUDED
STATIONARY FRONT
MID-LATITUDE
CYCLONES***
PRIMARY WEATHER PRODUCERS IN
MID- LATITUDES [30 –60 DEGREES]
LARGE CENTERS OF LOW
PRESSURE THAT GENERALLY
TRAVEL FROM WEST TO EAST
LASTING FROM A FEW DAYS TO
MORE THAN A WEEK
COUNTERCLOCKWISE MOTION