Chapter 18Test 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

WITH FEWER AIR MOLECULES IN THE UPPER ATMOSPHERE, THE PRESSURE DECREASES AS WE RISE IN THE ATMOSPHERE

IT DECREASES AT AN INCREASING RATE

MOUNTAIN SICKNESS DIZZY HEADACHE SHORTNESS OF BREATH RED BLOOD CELL COUNT NEEDS TO

INCREASE THINK CUBS WILL WIN IT ALL

AIR PRESSURE DIFFERS FROM ONE PLACE TO ANOTHER AND THESE MIGHT NOT BE FROM ELEVATION DIFFERENCES ALONE

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

RISING PRESSURE = IMPROVING WEATHER FALLING PRESSURE = STORMY WEATHER STEADY PRESSURE = WEATHER STAYS THE

SAME

COLD OR WARM AIR?

DRY OR MOIST AIR?

WHEN MOISTURE IS ADDED TO THE AIR, A HEAVIER GAS IS REPLACED BY THE WATER VAPOR SO MOIST AIR IS LIGHTER THAN DRY AIR

DIVERGENCE OF AIR

ANTICYCLONE

CONVERGANCE OF AIR

CYCLONE

MILLIBARS = 1014 MB AT SEA LEVEL

INCHES = 29.92 INCHES AT SEA LEVEL

BAROMETER - MERCURY /ANEROID ( LEGENDS ON THE DIAL)

BAROGRAPH ALTIMETER

◦ Chapter 18◦ Test 5 Material

PRESSURE GRADIENTS CORIOLIS EFFECT FRICTION CENTRIPETAL AND CENTRIFUGAL FORCE GRAVITY

A GRADIENT IS SIMPLY A CHANGE IN SOME PROPERTY WITH DISTANCE. PRESSURE GRADIENT IS DIFFERENCE IN AIR PRESSURE FROM ONE PLACE TO ANOTHER.

A GRADIENT IS SIMPLY A CHANGE IN SOME PROPERTY WITH DISTANCE. PRESSURE GRADIENT IS DIFFERENCE IN AIR PRESSURE FROM ONE PLACE TO ANOTHER.

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.

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.

AN INWARD PULLING FORCE

AN OUTWARD PULLING FORCE

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 WEEKCOUNTERCLOCKWISE MOTION