Factors Affecting Climate• Divide your paper into 4 squares.• Label them the following (4 front, 4 back):

1. Low Latitudes 5. Wind Patterns2. High Latitudes 6. Ocean Currents3. Mid-Latitudes 7. El Niño4. Elevation 8. Landforms

• Use Ch. 3 Sec. 2• You will write at least 3 main points for each IN

YOUR OWN WORDS!• Draw a colored Illustration for each! • Leave room for extra notes I may have!

LACEMOPLACEMOPFactors that shape

Weather and Climate

LatitudeLatitudeEarth-Sun Relationships — seasons and atmospheric scattering and energy spreading.

Low LatitudesLow Latitudes Between the Tropic of Cancer and Tropic of

Capricorn (includes Equator); the “Tropics” Low numbers in latitude value

Receive direct rays from Sun Equator: 6 mos. a yr. Each Tropic: 3 mos. a yr.

Receive indirect rays from Sun Equator: 6 mos. a yr. Each Tropic: 6 mos. a yr.

Warm to hot climates year round

Mid LatitudesMid Latitudes Most variable weather on Earth Between Tropic of Cancer & Arctic Circle;

between Tropic of Capricorn & Antarctic Circle

Ranges from fairly hot to fairly cold (temperate), dramatic changes, but moderate

Summer gets warm air from tropics, winter gets cold air from high-latitudes

High Latitudes

Polar areas= N of Arctic Circle and S of Antarctic Circle (high numbers in latitude value)

Receives constant sunlight for 6 months when pole faces Sun March-Sept: North has constant daylight,

South is in dark (switches for next 6 mos.) Arctic & Antarctic Circles are last point

to receive indirect rays (during summer or winter)

Air MassesAir MassesAir masses take on the “weather” of the place from which they came.

The meeting of two air masses is a front.

Air MassesAir Masses

Convectional Precipitation:Typical of hot climates; convection occurs after morning sunshine heats warm moist air. Clouds form in the afternoon and the rain falls.

Near Equator

Convectional PrecipitationConvectional Precipitation

Frontal Precipitation — when 2 fronts of different temperatures meet.

Warm air forced upward by heavier, cool air.

Rising warm air cools = precipitation--Most common type

Mid-Latitudes

a) summer—warm masses of air from the Tropics

b) winter– cold masses of air from the high latitudes

ElevationElevation

a)Height above sea level

b) Temperature decreases as elevation increases

ElevationElevation At any latitude, anywhere on Earth,

elevation influences climate If high enough in elevation, can have

snow on the Equator As altitude increases, the air thins which

absorbs less heat As elevation increases, temperature

decreases

MMountain Barriersountain Barriers•Blocks air masses and causes precipitation.

• Orographic Precipitation: warm moist air forced upward when passing over a mountain. Warm winds cool as they rise over the mountains and clouds form

• Air is warm and dry on the other side

• Windward: mountain side which faces the ocean

• Leeward: mountain side which is in a “rain shadow” (no precipitation received)

Ganges Plain in India Himalaya Arid Tibetan Plateau

OOcean Currentscean Currents• Help to distribute heat

• Carry warm water from tropics to poles and return cold water to the Equator

• Winds affect current movement

• Air masses take on water temperature

PPressure & Windressure & Wind•Rising warm air = low pressure

•Falling cool air = high pressure

•Wind moves high to low

•Movement from equator to poles and back

•Coriolis Effect: rotation of the earth bends the patterns of the wind

Winds blow in constant patterns and are called prevailing winds.

Historical Fact:Historical Fact: Many were named for the direction they blew…some were even given names because they were used by trading ships through the region…

Trade winds -- blow from the northeast toward the Equator and from the southeast toward the equator

Westerlies – prevailing winds in the mid-latitudes blow diagonally west to east

Polar Easterlies – blow diagonally in the high latitudes east to west—pushing the cold air toward the mid latitudes

Doldrums: windless area near the equator

Horse Latitudes: Historically, ships would lighten their loads in order to take advantage of the slightest wind such as cargo, excess supplies and livestock…this also included horses.

Move clockwise in N. Hem. and counterclockwise in S. Hem. (Coriolis Effect)

Cool air flows in to replace rising warm air (Polar front), distributing Sun’s heat

Switches direction in each latitude zone Low latitudes have trade winds (northeasterly/southeasterly) Mid-latitudes have westerlies High latitudes have polar easterlies

*(named for direction they come FROM) Windless bands

Doldrums @ Equator Horse Latitudes @ Tropics

LandformsLandforms Landforms affect climates of places at the same latitude Bodies of water moderate temps. b/c they take a long time

to change temp. Gulf of MX is warm water keeps Houston warmer

Continentality– absence of lg. body of water means more drastic weather changes Nebraska can have hot summers and receive snow in the

winters (4 seasons instead of 2 ) Rainshadow effect

Cool air releases moisture on windward side of mountain; then hot, dry air moves to leeward side creating deserts

El Nino

Periodic change in currents & water temps. in mid-Pacific region No known cause

Reversal of atmospheric pressures reduce or reverse wind patterns brings warm water from Asia to South America

Domino effect: Precipitation increases, flooding in S.

America Or droughts and fires in SE Asia/Australia

•http://www.teachersdomain.org/resource/ess05.sci.ess.watcyc.eselnino/