1. Ch. 24.1: Layers of the Atmosphere

2. Troposphere 0-12km Weather & Clouds Greatest air pressure & density (Gravity pulls air to surface) Temp. DECREASES with altitude WHY?

4. Stratosphere 12 km – 50 km, Temperatures WARM from -57C to 0C. Upper strat. is warmer than lower b/c of OZONE LAYER (This is unexpected)

5. OZONE LAYER Ozone absorbs UV that can be harmful to organisms. UV  Thermal Energy which warms strato. OZONE HOLE = Thinning of ozone layer) – Where: over poles – Cause: chemicals, CFCs (Chloroflourocarbons), used as coolants in refrigeration and aerosols, get into atmosphere and break apart ozone molecule … allowing more UV in.

6. Mesosphere 50-80 km, Temps decrease as altitude increases Top of Meso. is - 90 C Very thin air – moving VERY FAST. Windy (320 km/hr). This burns up meteoroids

8. Thermosphere OUTER MOST LAYER 80 km – outer space TEMP INCREASES w/ Alititude. ( - 90 C to more than 1000 C) B/C gas molecules in thermo. Absorb solar radiation – move fast – high temps

10. Ionosphere Part of THERMOSPHERE Region of charged particles (ions) that overlaps the lower thermoshere. Molecules absorb solar energy and b/cm (+) charged or IONS. Aurora – Charged particles are attracted to E’s mag. Poles – collide w/ ions & glow

11. Challenge Air exerts 14.7 pounds of pressure on each square in of Earth’s surface. Air Pressure = 14.7 lbs/in^2 How much would YOU have to weigh to exert the same pressure on Earth?