1. Case Studies of Important Scientific and Technological Issues Nature and Development of Science and Technology

2. Global Warming Introduction Greenhouse Effect and

3. Composition of the Earth’s Atmosphere (Gases – Percent by Volume) Other – 1.4% Oxygen – 20.6% Nitrogen – 78% Argon (0.934%) Water Vapor (0.4%) * Carbon Dioxide (0.035%) Neon (0.00182%) Hellum (0.000524%) * Methane (0.00015%) Krypton (0.000114%) Hydrogen (0.00005%) * N 2 O (0.00003%) * Ozone (0.000005%) * CFC S (0.0000001%) * Known Greenhouse Gas 78% nitrogen 20.6% oxygen < 1% argon 0.4% water vapor 0.036% carbon dioxide traces gases: Ne, He, Kr, H, O3 Methane, Nitrous Oxide

4. Burning of fossil fuels Source: OSTP

5. Deforestation Source: OSTP

6. Greenhouse Effect

7. The Greenhouse Effect Some solar radiation is reflected by the Earth and the atmosphere. SUN Solar radiation pass through the clear atmosphere. ATMOSPHERE EARTH Some of the infrared radiation passes through the atmosphere, and some is atmosphere and re-emitted in all directions by greenhouse gas molecules. The effect of this is to warm the Earth’s surface and the lower atmosphere. Most radiation is absorbed by the Earth’s surface and warms it. Most radiation is absorbed by the Earth’s surface and warms it. Infrared radiation is emitted from the Earth’s surface. Infrared radiation is emitted from the Earth’s surface.

8. Greenhouse Effect & Global Warming The “greenhouse effect” & global warming are not the same thing. Global warming refers to a rise in the temperature of the surface of the earth An increase in the concentration of greenhouse gases leads to an increase in the the magnitude of the greenhouse effect. (Called enhanced greenhouse effect) This results in global warming

9. Is Global Warming occurring?

10. Global warming doesn’t exist! Okey, it exists, but it isn’t man-made! 1990 1995 20002005 OK, so It’s man- made, but it’s effects aren’t all bad It’s effects will be really bad, but not until after I’m dead.