Download Introduction to Weather PPT

INTRODUCTION TO WEATHER
Sketch:
ATMOSPHERE
• ALL THE LAYERS OF AIR THAT SURROUND EARTH
• TROPOSPHERE:
• LAYER WHERE ALL WEATHER OCCURS, CLOUDS FORM
• WHERE WE LIVE
• 1ST LAYER, EXTENDS FROM THE SURFACE OF THE EARTH UP TO 620 KM HIGH
• WATER VAPOR & CARBON DIOXIDE FOUND HERE
• AS ALTITUDE INCREASES, TEMPERATURE DECREASES
• AIR PRESSURE = FORCE OF AIR PUSHING ON THE EARTH
• AS ALTITUDE INCREASES, AIR PRESSURE DECREASES
WATER CYCLE
• PROCESS IN WHICH WATER
CONTINUOUSLY CYCLES
BETWEEN THE TROPOSPHERE,
LAND, AND OCEAN
• CAUSED BY SUNLIGHT AND
GRAVITY
• SUNLIGHT- CAUSES
EVAPORATION (WATER TURNS
INTO A GAS)
• GRAVITY- PULLS WATER
DOWN DURING RAIN AND
HELPS CARRY WATER
DOWNHILL TO LARGE BODIES
OF WATER
PRECIPITATION
• OCCURS AFTER CONDENSATION
• PULLED DOWN BY GRAVITY
• RAIN, SNOW, SLEET, HAIL, FREEZING RAIN –
DEPENDS ON WEATHER CONDITIONS
(TEMPERATURE)
• TEMPERATURE VARIATIONS IN CLOUDS AND
BETWEEN CLOUDS & GROUND DETERMINE
THE TYPE OF PRECIPITATION
• EX:
• WARM AIR = RAIN
• FREEZING CLOUDS + WARM GROUND = RAIN
EVAPORATION/TRANSPIRATION
• WATERS ENTERS THE ATMOSPHERE IN THE FORM OF
WATER VAPOR
• CHANGE FROM LIQUID TO GAS
• THERMAL ENERGY FROM THE SUN CAUSES WATER TO
EVAPORATE OR TRANSPIRE
• EVAPORATION = ANY BODY OF WATER
• TRANSPIRATION = WATER ESCAPING THROUGH
PLANT LEAVES
CONDENSATION/CRYSTALLIZATION
• WATER VAPOR RISES IN THE
ATMOSPHERE
• TURNS INTO WATER DROPLETS OR
ICE CRYSTALS
• MUST OCCUR ON A SURFACE
• DUST PARTICLES SERVE AS A
“SURFACE” IN THE AIR
• FORMS CLOUDS
• WARM, MOIST AIR “HUDDLE”
TOGETHER IN THE COOL
TEMPERATURES OF THE TOP OF THE
TROPOSPHERE
EXAMPLES OF
CONDENSATION & CRYSTALLIZATION
• DEW = FORMS WHEN WATER VAPOR CONDENSES DIRECTLY ONTO A SURFACE
• WATER ON THE GRASS IN THE MORNING
• FROST = FORMS WHEN WATER VAPOR CHANGES FROM GAS INTO ICE CRYSTALS ON A
SURFACE
• TEMPERATURE MUST BE FREEZING (32OF OR BELOW)
• INCREASING THERMAL ENERGY = EVAPORATION
• DECREASING THERMAL ENERGY = CONDENSATION (CLOUDS, DEW, FROST)
DOWNHILL FLOW OF WATER ON LAND
• PRECIPITATION MAY OFTEN FALL ON LAND
• WATER RUSHES TO SEA LEVEL- PULLED BY
GRAVITY
• SURFACE-WATER FLOW: WATER RUNS ON TOP
OF LAND TOWARDS SEA LEVEL
• RIVERS, STREAMS, ETC.
• GROUND IS NOT POROUS (SOAKS UP WATER)
AND TOO MUCH WATER STAYS ON TOP
• GROUND-WATER FLOW: WATER SINKS INTO
THE GROUND AND GETS PULLED TOWARDS
SEA LEVEL
• GROUND IS POROUS AND THE SOIL SOAKS UP
THE WATER
MEASURING WEATHER
• METEOROLOGIST USE SPECIFIC TOOLS TO
MEASURE DIFFERENT WEATHER PHENOMENON
(THINGS THAT HAPPEN IN NATURE)
• CAN BE USED TO REPORT WEATHER, MAKE MAPS,
ETC.
WIND SPEED
• MEASURED USING AN ANEMOMETER
• WIND MAKES THE CUPS SPIN
• ANEMOMETER COUNTS THE
NUMBER OF TIMES IT SPINS IN A
CERTAIN AMOUNT OF TIME
• MORE TURNS = FASTER WIND
SPEED
• UNIT OF MEASURE = MILES PER
HOUR (MPH)
WIND DIRECTION
• MEASURED USING A WIND VANE
• DIRECTION OF THE WIND = DIRECTION FROM WHICH THE WIND IS BLOWING
PRECIPITATION
• MEASURED USING A RAIN GAUGE
• MARKINGS SHOW HOW MUCH RAIN HAS
FALLEN
• UNIT OF MEASURE = INCHES
TEMPERATURE
• MEASURED USING A THERMOMETER
• SCALE MAY BE READ IN CELSIUS OR
FAHRENHEIT
•
OC
OR OF
AIR PRESSURE
• MEASURED USING A BAROMETER
• UNIT OF MEASURE = INCHES OF
MERCURY OR MILLIBARS
HUMIDITY
• MEASURED USING A SLING
PSYCHROMETER
• USES 2 THERMOMETERS
• WET/DRY BULB TO MEASURE HUMIDITY
IN THE AIR
• HUMIDITY = HOW MUCH WATER
VAPOR IS IN THE AIR
• TEMPERATURE READINGS ARE
CONVERTED USING A RELATIVE
HUMIDITY TABLE