Solar Radiation Powers all life Albedo  The reflectance of solar energy off earth’s surface  Dark colors = low albedo  Forests and ocean  Light colors = high albedo  Ice caps o Sun provides energy for life, powers biogeochemical cycles, and determines climate

Weather and Climate Weather  The conditions in the atmosphere at a given place and time  Temperature, precipitation, cloudiness, etc. Climate  The average weather conditions that occur in a place over a period of years  2 most important factors: temperature and precipitation  Earth as many climates

Temperature Changes with Latitude Solar energy does not hit earth uniformly  Due to earth’s spherical shape and tilt Equator (a) High concentration Little Reflection High Temperature Closer to Poles (c) Low concentration Higher Reflection Low Temperature From (a) to (c) In diagram below

Temperature Changes with Season Seasons determined by earth’s tilt (23.5°) Causes each hemisphere to tilt toward the sun for half the year o Northern Hemisphere tilts towards the sun from March 21- September 22 (warm season)

Surface Winds Rotation of earth causes winds to be reflected Earth spins faster at the equator Winds are deflected— known as prevailing winds Northern Hemi—deflected right Southern Hemi-- left Low Low Low High High High High

Air circulation in the atmosphere Earth is warmest at its equator and its spins faster than poles This creates prevailing winds– belts of air that distribute heat and moisture—blow almost continuously

Well what is wind? Wind is formed by the movement of warm to areas of cooler air OR, can be said to be the movement of air from high pressure (warm air) to areas of low pressure (cooler air).

Convection currents (aka convection cell) As high pressure (warm air) is heated by sun Expands, becomes less dense, and rises These rising currents have ability to hold LOTS of moisture compared to surrounding air Warm air absorbs moisture begins to condense and cool (hence becoming going from high  to LOW pressure) Precipitation follows

Convection cell

Hadley cell Convection cells that can be found at 30 degrees north and south latitude from the equator Hot air rises are the equator, condenses and drops huge amounts of rain as it moves north or south Account for the rainforests of the world near the equator Account for the deserts little farther north or south of the cell

Tropical rainforests and deserts Note the rainforest s close to the equator, and deserts close to 30 degrees N latitude

Hadley Cells

Coriolis Effect The perceived deflection of moving objects “viewed from a turning frame of reference” Earth’s rotation influences direction of wind  Earth rotates from West to East  Deflects wind from straight-line path Coriolis Effect  Influence of the earth’s rotation on movement of air and fluids  Turns them Right in the Northern Hemisphere  Turns them Left in the Southern Hemisphere

Types of prevailing winds Remember—prevailing winds helps distribute air, heat, and moisture over the earth’s surface Tradewinds—exist between 30° N and S latitude Steady and strong—called “tradewinds” because steadily propelled trade ships Blow from the northeast in Northern Hemisphere Blow from southeast in Southern Hemisphere

 Remember WIND DIRECTION IS DEFINED BY THE DIRECTION IT IS COMING FROM NOT THE DIRECTION IT IS GOING!!  i.e. surfing– west wind– good! (wind comes from New Jersey land—blows towards the ocean, makes good waves

West wind waves Notice the direction of the spray…………… Wind blows from west—to—east, gives waves a “hollowness”

East wind waves Wind blows from the east—toward—west Wind knocks waves over, makes them floppy and flat

Doldrums Air near equator is stagnant b/c constantly rising Why?

Ocean currents Prevailing winds, differences in salinity, and Coriolis Effect create ocean currents Currents smack into continents and cause a roughly circular pattern N. hemi– clockwise direction S. hemi– counter clockwise direction

Vertical Mixing of Ocean

Gyres

Global Ocean Circulation Trade winds Westerlies

Layers of Earth’s Atmosphere

Atomosphere whatttt!!! Rippin up the troposphere.... Part II

So how does all this movement of air/water create climates? shadow One way….. Rain shadow effect Warm air from the coast is blown inland Travels up a mountainside– sucks up moisture from plants and soil below Air condenses, releases precipation Air falls to opposite side of mountain very hot, dry

El Niño What is El Niño? Nat geo El Nino-- good overall El Nino-- Telecom good animations El Nino-- Australia documentary, good biota