1. 1 Global Changes in the Atmosphere Global Warming and Ozone Depletion msnbcmedia.msn.com/j/msnbc/Components/Photos/...

2. 2 Global Warming Over the last 120 years, the average temperature of the troposphere( the layer of the atmosphere closest to Earth) has risen by 0.5° Celsius Over the last 120 years, the average temperature of the troposphere( the layer of the atmosphere closest to Earth) has risen by 0.5° Celsius Global Warming is the gradual increase in the temperature of Earth’s atmosphere Global Warming is the gradual increase in the temperature of Earth’s atmosphere The Greenhouse Effect is a natural process by which heat is trapped in the atmosphere by water vapor, carbon dioxide, methane and other gases that form a “blanket” around the Earth. The Greenhouse Effect is a natural process by which heat is trapped in the atmosphere by water vapor, carbon dioxide, methane and other gases that form a “blanket” around the Earth.

3. 3 Global Warming The gases that trap solar energy are called greenhouse gases. The greenhouse effect helps life to exist on Earth. The gases that trap solar energy are called greenhouse gases. The greenhouse effect helps life to exist on Earth. Human activities that add greenhouse gases to the atmosphere may be warming Earth’s atmosphere. Human activities that add greenhouse gases to the atmosphere may be warming Earth’s atmosphere. Burning wood, coal, oil, and natural gas adds carbon dioxide to the atmosphere. Burning wood, coal, oil, and natural gas adds carbon dioxide to the atmosphere.

4. 4 Ozone Depletion Ozone is a gas in the stratosphere, a high layer of the atmosphere, that absorbs most of the ultraviolet radiation that strikes Earth from the sun. Ozone is a gas in the stratosphere, a high layer of the atmosphere, that absorbs most of the ultraviolet radiation that strikes Earth from the sun. Chemicals produced by humans have been damaging the ozone layer, chloroflourocarbons (CFC’s) are the main cause Chemicals produced by humans have been damaging the ozone layer, chloroflourocarbons (CFC’s) are the main cause

5. 5 Ozone Depletion A decrease of ozone in the stratosphere means more ultraviolet radiation strikes Earth’s surface, and us. Ultraviolet radiation can cause A decrease of ozone in the stratosphere means more ultraviolet radiation strikes Earth’s surface, and us. Ultraviolet radiation can cause - sunburns -eye damage - skin cancer

6. 6 Melting Glaciers/ Ice Caps http://msnbcmedia.msn.com/j/msnbc/Components/Photos/060619/060619_parks1_glacier_hlrg_9a.hlarge.jpg http:// www.explorersweb.com/sitemedia/TSthumbs/everest/kili3.jpg www.earthman.tv/.../MeltingGlacier2.jpg

7. 7 Melting Glaciers/ Ice Caps http://www.savebiogems.org/images/polar/map.gif

8. 8 http://ozonewatch.gsfc.nasa.gov/facts/images/ozone_hole.jpg