1. Chapter 11 - Atmosphere

2. Atmospheric Conditions
About 99% of the Earth’s atmosphere is composed of nitrogen and oxygen
The remaining 1% consists of argon, hydrogen, carbon dioxide, water vapor and gases

3. Key Atmospheric Gases
The amount of water vapor and carbon dioxide in the atmosphere depending on location
Water vapor is the source of clouds, rain, and snow
Water is the only substance that exists in 3 states
The atmosphere also contains tiny solids
Dust is carried there by wind, salt is picked up from ocean spray (these play a role in cloud formation)

4. Ozone
Ozone (O3) exists in small quantities in a layer well above Earth’s surface
It absorbs UV radiation