earth sun relationships. climate and weather how do the relationships btwn earth and the sun affect...

EARTH SUN RELATIONSHIPS

CLIMATE AND WEATHERHow do the relationships btwn Earth and the sun affect climate?

WEATHER• Def: condition of the

atmosphere in one place during a short period of the time

• How do you tell what the weather is like?----Look out the window

CLIMATE• Def: weather patterns typical

for an area over a long period of time

• Directly affected by Earth/Sun relationships

EARTH’S TILT AND ROTATION• AXIS: imaginary line; runs

through center of Earth btwn N and S Poles

• Earth tilts on the axis at 23.5°

• Affects amount of direct sunlight, which affects temperature

• Our rotation takes 24 hours

EARTH’S REVOLUTION• REVOLUTION: in astronomy,

the Earth’s yearly trip around the sun

• 365 ¼ days

• Tilt and revolution affect amt of sunlight that hits the Earth

EQUINOX• Def: one of 2 days on which

the sun is directly above the Equator, making day and night equal in length

• Around March 21 and September 23

• Mark the shift in seasons

SOLSTICE• Def: one of 2 days on which

the sun’s rays strike directly on the Tropic of Cancer or the Tropic of Capricorn

• June 21: Summer Solstice---longest day in N. hemisphere

• December 22: Winter Solstice---shortest day

MIDNIGHT SUN• C. March 20-September 23

• North of Arctic Circle (66 1/2°N) has continuous daylight

• South Pole for the other 6 months

GREENHOUSE EFFECT• Radiation from sun heats the

Earth

• Water vapor, methane, and CO2 trap some of the radiation

• This causes temps to rise

FACTORS AFFECTING CLIMATEHow are climate patterns related to each zone of latitude?

LATITUDE AND CLIMATE• Low latitudes: btwn 30°S and

30°N---get direct sun rays year-round; warm to hot climates

• High latitudes: 60°N to 90°N and 60°S to 90°S---the Poles; get continuous, but indirect sun

• Midlatitudes: btwn 30°N and 60°N (vice versa for S)---most variable weather

ELEVATION AND CLIMATE• Earth’s atmosphere thins as

altitude increases

• Retains less heat

• Temp decreases 3.5°F for every 1000 ft. up

WINDS• Wind is air moving across

surface of Earth

• Sunlight heats atmosphere unevenly

• Warm air rises, creating areas of low pressure

• Cool air sinks, causing high pressure

• Air moves along the warm and cold, distributing the sun’s energy around the planet

WIND PATTERNS• PREVAILING WINDS: wind in

a region that blows in a fairly constant directional pattern

• Determined by latitude and Earth’s movement

• CORIOLIS EFFECT: resulting deflection of prevailing winds caused by Earth’s rotation

• DOLDRUMS: a frequently windless area near the Equator

OCEAN CURRENTS• Def: cold or warm stream of

seawater that flows in the oceans, generally in a circular pattern

• Cold water from Poles move toward Equator

• Warm water from Equator moves toward Poles

INFLUENCES ON WEATHER• Climate affected by recurring

events

• EL NIÑO: periodic reversal of the pattern of ocean currents and water temperatures in the mid-Pacific region

LANDFORMS AND CLIMATE• Large bodies of water keep

temps moderate

• Mountain ranges push wind up, creating precipitation

• Rain falls on WINDWARD side

• Winds then move down the LEEWARD side

• Creates a RAIN SHADOW: dry areas on the leeward side of mtns

WORLD CLIMATE PATTERNSWhy is climate important to life on Earth?

CLIMATE ZONES• 4 types:

• 1: Tropical Climate

• Avg daily temp: 80°F

• Rains almost daily (avg rainfall: 50-260 inches annually)

• Thick vegetation

• Abundant wildlife

CLIMATE ZONES CONTINUED• 2: Dry Climates

• 2 main types

• A: Semi-arid (steppe) : located away from oceans

• Avg rainfall: 10-30 inches

• Warm summers, harsh winters

• B: Desert: avg rainfall---10 inches

• Very little plant/animal life

STILL MORE CLIMATE ZONES• 3: Midlatitude climate:

• Includes: a) Humid subtropical—high humidity; mild winters; year-round rain

• Vegetation: prairies

• --Coniferous trees: cone-bearing; needle shaped leaves

• --Deciduous trees: broad leaf

MIDLATITUDES CONTINUED• B) Marine west coast climate

• Cool summers; cool, damp winters

• Abundant rainfall

• Mixed forests

• C) Mediterranean climate

• Mild, rainy winters; hot, dry summers

• Vegetation: woody bushes and short trees

MIDLATITUDES CONTINUED• D) Humid continental

• Inland, so not affected by ocean winds

• Farther north, harsher winters and cooler summers

• Vegetation: mixed

HIGH-LATITUDE CLIMATES• Freezing temps year-round

• Includes:

• A) Subarctic climates

• Has PERMAFROST: permanently frozen layer of soil

• B) Tundra climate

• Very limited heat

• Vegetation: low bushes, moss, lichen

CLIMATE CHANGE• Major changes in climates over

extended periods of time

• Global temps have increased 1.4°F over last 100 years

• Causes severe weather changes

• Earth does have natural cycles of climate change

• Increased greenhouse gas emission creates acid rain

• Acid rain kills trees

• Fewer trees to scrub the air