A COLOUMN OF AIR THAT STRETCHES FROM THE TOP OF THE ATMOSPHERE TO SEA LEVEL WAS A WEIGHT OF 14.7 POUNDS.
AIR PRSSURE IS THE WEIGHT OF THE ATMOSPHERE AS IT PUSHES DOWN UPON EARTH’S SURFACE. (THE WEIGHT OF THE ATMOSPHERE AS IT PUSHES DOWN UPON EARTHS SURFACE)
AIR PRESSURE IS EXERTED IN ALLL DIRECTIONS BC AIR MOLECULES MOVE IN ALL DIRECTIONS.
AIR PRSSSURE DECREASES AS ELEVATION INCREASES.
THE INSTRUMENT USED TO MEASURE AIR PRESSURE IS THE BAROMETER.
THERE ARE TWO MAIN TYPES OF BAROMETERS: MERCURY AND ANEROID
MERCURY: A GLASS TUBE FILLED W MERUCRY IS INVERTED AND PLACED UPRIGHT IN A DISH OF MERCURY. THE MERCURY FLOWS FROM THE TUBE INTO THE DISH UNTIL THE WEIGHT OF THE MERCURY COLOUMN IS EQUIVALENT TO THE AIR PRESSURE ON THE MERCURY ON THE DISH.
WIND IS GENERATED BECAUSE THE WIDNS TRY TO BALANCE OUT THE HIGHS AND LOWS OF AIR PRESSURE AND THEIR DIFFERENCES. SOLAR RADITIAION IS THE ULTIMATE ENERGY SOURCE OF MOST WIND. ALSO, PRESSURE GRADIENT, CORIOLIS EFFECT AND FRCITION AFFECT WINDS.
PRESSURE GRADIENT IS THE AMOUNT OF PRESSURE CHANGE (WHAT DIRECTION AND RATE). High pressure is centered at Wichita, and low pressure is centered at Columbus.
THINGS THAT AFFECT AIR PRESSURE:
ALTITUDE, TEMPERATURE, HUMIDITY
ALTITUDE: THE HIGHHER THE ALTITUDE, THE LOWER THE AIR PRESSURE
THE LOWER THE ALTITUDE, THE MORE AIR PRESSURE
AS TEMPERATURE GOES UP, AIR PRESSURE GOES DOWN
THAT’S WHY HOT MOLECULES ARE LESS CONDENSED THAN COLD ONES (LESS DENSE)
AS THE