Transcript Chapter 15 Atmosphere

Chapter 15
Atmosphere
15.1 Earth’s Atmosphere
Composition
1. Gas (78% N2, 21% O2)
2. Solids & Liquids
- Dust, salt and water
Structure
2 lower layers
1. Troposphere
- Closest to ground (~ 11 miles high)
- Contains most gas and water vapor
- Where weather occurs
2. Stratosphere
- 2nd layer (~21 miles high)
- Contains ozone layer
3 Upper layers
3. Mesosphere
- Coldest layer (~40 miles high)
- Meteors burn up (shooting star)
4. Thermosphere
- Hottest layer (~1,000-2,000 °F)
- Aurora occur here
- Contains Ionosphere (charged particles)
- ~ 430 miles high
- Space Shuttle & ISS orbit here
5. Exosphere
- Uppermost part of Earth
- Space is after
- ~ 6200 miles high
Atmospheric Pressure
- Most dense at sea level
- Barometer- Measures air pressure
Temperature
- Atmosphere divided into layers by temperature
Ozone layer
- Shield & absorbs UV rays
- CFC’s destroy ozone
15.2 Energy from Sun
Energy Transfer
Radiation
- Transfer energy by electromagnetic waves
- Light & heat Ex) Fire, Sun
Conduction
- Heat transfers as molecules collide
Convection
- Heat transfer through gas or liquid
Ex. Dryer, Oven
Water
Hydrosphere
- All water on Earth’s surface
- 97% is salt water
- Most fresh water is in polar ice caps
Water Cycle
- Movement of water between Earth & atmosphere
15.3 Air Movement
Wind Formation
- Uneven heating of Earth
Coriolis effect
http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/crls.rxml
http://www.classzone.com/books/earth_science/terc/content/visualizations/es1904/es1904page01.cfm?chapter_no=19
- Water & air move Right above equator & Left
below
Wind Systems
1. Jet stream- Belts of strong wind in upper
troposphere
2. Doldrums- Windless area at equator
3. Prevailing Westerlies- Move most weather in
USA- west to east
4. Sea breeze (Day) - Wind blowing from sea
to land
5. Land breeze (Night) - Wind blowing from
land to sea