Transcript Weather 2 notes

HOW DOES ENERGY GET INTO
THE ATMOSPHERE?
-THE SUN IS THE MAJOR SOURCE
OF ENERGY FOR THE EARTH
THE ELECTROMAGNETIC SPECTRUM
-THE SUN AND OTHER STARS GIVE
OFF ENERGY IN A WIDE RANGE OF
WAVELENGTHS THAT MAKE UP THE
ELECTROMAGNETIC SPECTRUM
*SHORT WAVES:
GAMMA, X-RAYS AND ULTRAVIOLET
-THE EARTH’S ATMOSPHERE
FILTERS OUT MOST OF THE
DANGEROUS SHORT WAVE
RADIATION
*LONG WAVES
-INFARED AND RADIO WAVES
-MOST OF THE OUTPUT THAT
REACHES THE EARTH’S SURFACE
IS
VISIBLE LIGHT
THE EARTH INTERCEPTS ONLY A
SMALL FRACTION OF THE ENERGY
RADIATED FROM THE SUN!
-APPROXIMATELY ¾ OF THIS
ENERGY IS USED TO EVAPORATE
WATER FROM THE OCEANS
EVAPORATION:
-CHANGE OF STATE FROM LIQUID
TO GAS
-ADDS ENERGY AND MATTER TO
THE ATMOSPHERE
FACTORS THAT INCREASE THE
RATE OF EVAPORATION
1) WATER IS UNCOVERED
2) THE WATER IS HEATED
3) WHEN WIND BLOWS OVER IT
*THE THREE STATES OF WATER*
FIGURE 7-4 IN REVIEW BOOK
HEAT OF FUSION:
-THE ENERGY NEEDED TO MELT
ONE GRAM OF A SUBSTANCE AT
ITS MELTING POINT
-THE HEAT OF FUSION OF ICE IS
80 CALORIES PER GRAM
HEAT OF VAPORIZATION:
-THE ENERGY NECESSARY TO
CHANGE ONE GRAM OF A SUBSTANCE
FROM LIQUID TO VAPOR
STATE.OCURRS AT 100Oc
-HEAT OF VAPORIZATION OF
WATER IS 540 CAL/G
-IF WATER VAPOR IS COOLED TO
100Oc, IT WILL CONDENSE AND
RELEASE 540 CLAORIES OF LATENT
HEAT (KINETIC ENERGY)
ENERGY IN THE ATMOSPHERE:
*RELEASE ENERGY:
-CONDENSATION AND FREEZING
*ABSORB ENERGY:
-MELTING AND EVAPORATION
-WATER VAPOR HOLDS AN
ENORMOUS AMOUNT OF ENERGY AND
IS THE MAIN RESOURCE OF ENERGY
SYNOPTIC WEATHER MAP
-WEATHER MAPS THAT SHOW A
VARIETY OF ATMOSPHERIC FIELD
QUANTITIES
-SHOW INFORMATION ABOUT
TEMPERATURE,AIR PRESSURE,
PRECIPITATION, AND OTHER
CONDITIONS OVER A LARGE
GEOGRAPHIC AREA.
STATION MODELS
-USED TO REPRESENT VARIOUS
WEATHER CONDITIONS IN
DIFFERENT LOCATIONS
- STATION MODELS ARE IN
ABBREVIATED FORM BECAUSE OF
THE LARGE AMOUNT OF
INFORMATION THEY CONTAIN
A STATION MODEL
TEMPERATURE
PRESENT
WEATHER
DEW POINT
PRESSURE
PRECIPTATION
.25
CLOUD
COVER
WIND
DIRECTION
WIND SPEED
DECODING PRESSURE ON A
STATION MODEL
EXAMPLE:
121
1) PLACE A DECIMAL POINT BETWEEN
THE 2ND AND 3RD DIGITS
12.1
2) IF THE FIRST NUMBER IS LESS
THAN 5, PLACE A 10 BEFORE THE
FIRST NUMBER
1012.1
EXAMPLE:
856
STEP 1:(DECIMAL POINT)
85.6
STEP 2: IF THE FIRST NUMBER IS 5
OR GREATER, PLACE A 9 IN FRONT OF
THE FIRST DIGIT
985.6
-WEATHER MAPS ARE USEFULL TO
IDENTIFY BODIES OF AIR WITH
UNIFORM TEMPERATURE, PRESSURE
AND HUMIDITY CALLED AIR MASSES.
-IT IS THE MOVEMENT OF AIR
MASSES THAT BRINGS CHANGES IN
THE WEATHER
-THE CHARACTER OF AN AIR MASS
DEPENDS ON ITS GEOGRAPHIC
ORIGIN
* CONTINETAL AIR IS DRY
* MARITIME AIR IS MOIST
*TROPICAL AIR IS WARM
*POLAR AIR IS COLD
cA
* ARCTIC AIR IS EVEN COLDER
CONTINENTAL ARCITC: AN
UNUSUALLY COLD AND DRY
AIR MASS FROM CANADA
cP
CONTINENTAL POLAR: A COLD,
DRY AIR MAS THAT MAY HAVE
ORIGINATED OVER CENTRAL
CANADA
cT
CONTINENTAL TROPICAL: A
WARM, DRY AIR MASS, THAT
MAY HAVE ORIGINATED OVER
MEXICO OR THE AMERICAN
SOUTHWEST DESERT REGION
mT MARITIME TROPICAL: A WARM,
MOIST AIR MASS, THAT MAY
HAVE ORIGINATED OVER THE
GULF OF MEXICO
mP: MARITIME POLAR: A COLD,
MOIST AIR MASS THAT MAY
HAVE ORIGINATED OVER THE
NORTH ATLANTIC OR NORTH
PACIFIC OCEAN
HOW CAN WE PREDICT THE
WEATHER?
-WEATHER SYSTEMS USUALLY MOVE
ACROSS THE UNITED STATES FROM
WEST TO NORTH-EAST
-IF WE KNOW THE WEATHER IN
CHICAGO, YOU HAVE A ROUGH
INDICATION OF NEW YORK A DAY
OR TWO LATER
HIGHS AND LOWS
HIGH PRESURE CENTERS:
-REPRESENTED BY A LARGE “H”
ON A WEATHER MAP
-“ANTICYCLONE”. WINDS MOVE IN
A CLOCKWISE DIRECTION
-ZONES OF DIVERGENCE, WHERE
SINKING AIR AT THE CENTER
CAUSES AIR TO BLOW OUTWARD
-BRING COOL DRY AIR WITH
CLEAR SKIES AND STABLE
CONDITIONS
LOW PRESSURE CENTERS
-REPRESENTED BY A LARGE “L” ON A
WEATHER MAP
-”CYCLONE”: WINDS MOVE IN A
COUNTER-CLOCKWISE DIRECTION
-GENERALLY AREAS OF WARM
MOIST WEATHER
-RISING AIR AT THE CENTER OF
THE LOW DRAWS IN CONTRASTING
AIR MASSES ALONG WITH THEIR
ASSOCIATED FRONTS
-ASSOCIATED WITH CHANGEABLE
WEATHER, CLOUDY SKIES AND
PRECIPIATION
FRONTS:
-SHOWN BY LINES THAT SEPARATE
TWO AIR MASSES
-OFTEN FOUND IN LOW PRESSURE
SYSTEMS BECAUSE OF THE DIFFERENT
AIR MASSES THAT CONVERGE TO
FORM A CYCLONE
-UNSTABLE CONDITIONS ALONG
THE FRONT BOUNDARY
SYMBOLS FOR FRONTS
-SYMBOLS POINT IN THE DIRECTION
THE FRONT IS MOVING
COLD FRONT
LEADING EDGE OF COOL AIR
COMES IN AND REPLACES WARM
AIR
WARM FRONT
LEADING EDGE OF WARM AIR COMES
IN TO REPLACE COOLER AIR
OCCLUDED FRONT
A COLD FRONT CATCHES UP TO A
WARM FRONT
STATIONARY FRONT
-CREATES STABLE CONDITIONS
March 14
MARCH 15
-STORMS ARE DESTRUCTIVE
MAINLY AS A CONSEQUENCE OF
THEIR ENERGY
-THE ENERGY BECOMES AVAILABLE
THROUGH THE PROCESS OF
CONDENSATION, WHICH OCCURS
WHEN CLOUDS FORM WITHIN THESE
STORMS
-VIOLENT STORMS CAUSE PROPERTY
DAMAGE AND OFTEN TIMES LOSS OF
LIFE!
THUNDERSTORMS
-MOST OCCUR IN THE SUMMER WHEN
THE AIR IS WARM AND MOIST.
-COLD AIR PUSHES INTO WARM AIR
FORCING THE WARM AIR UP QUICKLY
CAUSING GIANT CLOUDS AND LARGE
AMOUNTS OF PRECIPITATION
-USUALLY OVER IN LESS THAN AN
HOUR
TORNADOES
-MOST COMMON IN CENTRAL
UNITED STATES DURING SPRING
AND EARLY SUMMER
-MARITIME TROPICAL AIR FROM
THE GULF OF MEXICO COLLIDES
WITH COLDER AIR FROM THE
NORTH
-USUALLY LESS THAN O.3 MILES
IN DIAMETER
-WINDS ARE FASTER THAN
HURRICANES BUT DIFFICULT TO
MEASURE BECAUSE THEY ARE SO
SHORT LIVED (USUALLY MINUTES OR
LESS)
-WINDS IN SOME TORNADOES
WERE CLOCKED AT 280 MILES PER
HOUR BEFORE THE RECORDER BROKE
HURRICANES
-USUALLY DEVELOP IN LATE
SUMMER AND EARLY AUTUMN IN
THE ATLANTIC OCEAN BETWEEN
SOUTH AMERICA AND AFRICA
THE REGION HAS AN ABUNDANCE OF
SOALR ENERGY AND WARM TROPICAL
WATER
-THEY GATHER STRENGTH AS THE
DRIFT ACROSS THE ATLANTIC OCEAN
-GROW INTO HUGE ROTATING
SYSTEMS, WHICH AVERAGE 400
MILES ACROSS
-AT THE CENTER OF THE
HURRICANE, PRESSURE IS
EXTREMELY LOW.
THIS ALLOWS FOR A LARGE
PRESSURE GRADIENT TO DEVELOP
(HIGHER AND LOW PRESSURE ARE
VER CLOSE TOGETHER CAUSING
WIND TO BLOW FAST
-WHEN THE STORM MOVES INLAND
IT IS DEPRIVED OF ITS ENERGY
SOURCE; WARM, TROPICAL OCEAN
WATER
-IN A MATTER OF DAYS IT BECOMES
A MID-LATITUDE CYCLONE WITH THE
FRACTION OF THE POWER THAT IT
HAD AS A HURRICANE
Tornadoes
Likely area of formation
Area of U.S. most likely to
receive damage from
Size
Duration(How long they last)
Wind speed
Appearance
Time of year they are most
likely to form
Precautions
Hurricanes