Climate ChangeGreenhouse Effect

Mechanisms Affecting the Greenhouse

Evidence for Climate Change

Myth Busters Question

http://upload.wikimedia.org/wikipedia/commons/8/8e/Earth%27s_greenhouse_effect_%28US_EPA%2C_2012%29.png

NASA GREENHOUSE EFFECT

I. Greenhouse Effect1. Radiation from Sun enters atmosphere

a. Reflection (clouds, ice, water) b. Absorption by Surface

2. Earth’s surface creates infrared radiation a. Greenhouse gases trap infrared radiation b. CO2, H20, CH4

Greenhouse Simulator

II. Mechanisms Decreasing Greenhouse Temps

1. Increased Solar Reflection a. Volcanic ash, impact ash, glaciers b. Plate tectonics /ocean currents/ice caps

2. Less solar radiation from Sun (orbit/tilt)3. Less greenhouse gases (cycles)

Eruptions and Temperature

II. Mechanisms Increasing Greenhouse Temps

1. More greenhouse gasesa. Changes in cycles that recycle gasesb. Burning of fossil fuelsc. Volcanic gases

2. More solar radiation a. Changes in Earth’s tilt and orbit b. Positive feedback loops

Evidence for Climate Change

PAST PRESENTNorth America Ice

AgeGlacial material &

landforms, lakes, sea levels, extinctions

• Retreating Glaciers (melting)

• North pole ice sheet shrinking

Eocene Thermal Maximum

Sea levels, ocean core samples, extinctions

• Changing migrations • Species moving

northward

• Average global temps• Ocean temps• Sea Levels