Chapter 18 Test 5 material Begin

 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 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 = 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.

 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 BREEZESEA BREEZE* OCCURS AS LOW PRESSURE AREA DEVELOPS OVER LAND DURING HEAT OF DAY. AIR FLOWS FROM OCEAN TO LAND BRINGING IN COOLING WINDS.

KATABATICKATABATIC WIND COLD DRY MOUNTAIN WIND ALSO KNOWN AS MISTRAL & BORA CAN CAUSE EXTREMELY COLD TEMPERATURES IN A RELATIVELY SHORT PERIOD OF TIME.

CHINOOKCHINOOK 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 WATERMONSOON 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