AP Environmental Study Session 2

Tuesday March 22, 2011

Rock Cycle

Youtube Video 1: http://www.youtube.com/watch?v=F-h7G0h9Ip0&NR=1

Types of Rock

• Define– Igneous– Sedimentary– Metamorphic

Soil

• The crucial link between biotic and abiotic– What is found in soil?

• 3 constituents in differing percentages (%):– Clay• Smallest particle, <.002mm

– Silt• .002 - .05mm

– Sand• Largest particle, .05 – 2.0mm

pH and Soil

• pH Scale

• Acidic vs. Alkalinity

• Most soils are pH 4 – 8

• Importance of pH?– pH determines the availability of nutrients in the soil

Where does soil come from?• Weathering– Physical / Mechanical• Don’t change chem of the rocks• Wind and water

– Chemical• Do change chem of the rocks• Interactions between atmosphere, water, and rocks

– Biological• Activities by living organisms

Soil Layers

Human Caused Soil Problems

• Farming– Monoculture– Crop Rotation– Green Revolution– Salinization– Erosion – Dust Bowl

• Add nutrients to the soil in the form of fertilizers– What is all in fertilizers?

• To grow food we need arable land– Land we can grow stuff in

Soil Conservation• Recent efforts have been made to naturally

increase the productivity of farms via:– Using natural fertilizer….AKA ________– Modify tilling to not break-up the land as much to

decrease erosion– Create buffer zones using trees to decrease wind

erosion• Legislation– 1977: Soil and Water Conservation Ace– 1985: Food Security Act

Moving from the Lithosphere to the Atmosphere

Atmosphere

• Define• What’s in it?– Oxygen (21%)– Water Vapor– Nitrogen (78%)– Carbon Dioxide (.037%)– Argon (.9%)– Layers

• What layer do we live in?– Troposphere (surface - 20km)

Layers of the Atmosphere

Layers of the Atmosphere

• Troposphere– Where all weather occurs– Contains all water vapor and clouds– Well mixed and temp decreases as altitude increases

• Tropopause– Buffer zone between the troposphere and the stratosphere– Temp begins to increases as altitude increases

• Stratosphere– 20km – 50km– Gases not mixed, arranged according to density– Temp increases as altitude increases – due to Ozone layer

Greenhouse Effect

• Occurs primarily in the Troposphere

• http://www.youtube.com/watch?v=PC0VeBPasgQ&feature=related

• http://www.youtube.com/watch?v=CxUK2TizQ4g&feature=related

Ozone and why its important

• Found at the top of the stratosphere

• http://www.youtube.com/watch?v=WE3y1Gj2dec

• Ozone Depletion– http://www.youtube.com/watch?v=I1wrEvc2URE

&feature=related

Layers of the Atmosphere

• Mesosphere– 50km – 80km above the surface– Layer where meteors typically burn up

• Thermosphere / Ionosphere– 80km – 110km above the surface– Layer where auroras occur, space shuttles orbit,

and where radio waves reflect– Energy from the solar winds are absorbed here

Aurora - Ionosphere

• http://www.youtube.com/watch?v=YJBrMXSn-hU

• http://www.youtube.com/watch?v=PaSFAbATPvk&feature=related

Connecting Atmosphere and Climate

• Climate is created by the atmosphere• Weather is the daily fluctuations of:– Temperature– Sunlight– Air pressure– Winds– humidity

• Then what is climate and who studies it?** The climate and weather is caused by the unequal heating of the Earth’s atmosphere by the sun**

3 reasons Earth is unevenly heated

• More rays strike the Equator than anywhere else

• Tilt of the axis causes regions to receive more of less sunlight

• Surface is rotating faster at the equator than at the poles

http://www.youtube.com/watch?v=DHrapzHPCSA&feature=related