1. The Atmosphere Without the atmosphere, life would not exist. –Animals need oxygen to breathe. –The atmosphere is part of the carbon and nitrogen cycles which are necessary to bring vital nutrients to living things. –The atmosphere shields animals and plants from the harmful solar radiation. –Greenhouse gases (carbon dioxide, water vapor, and methane) help to warm Earth to temperatures suited for life. Air pollution – airborne particles and gases that occur in concentrations large enough to endanger the health of organisms.

2. Greenhouse Effect Short-wave solar radiation Greenhouse gases –Carbon dioxide –Water vapor –Methane –Nitrous oxide –CFC’s – chlorofluorocarbons

3. Measuring Global Warming Scientists first warning – 1896 First measurements confirming global warming – 1957 at Mauna Loa volcano in Hawaii Global air temperature – increased 0.6 o C between 1861 and 1988 Predicted average global air temperature will rise 1.4-5.8 o C by 2100

4. Causes of Global Warming

5. Potential Impact on Climate of Global Warming Northern regions of the Northern Hemisphere will heat up more Northern and mountain glaciers will shrink Less ice floating in northern oceans Regions with light winters  no snow Snowline in mountains will be higher and melt earlier Growing seasons will increase Winter and nighttime temperatures will rise more than summer and daytime temperatures More humidity and increased rainfall More frequent and intense storms Dry regions become drier