1. The Air Around You Notes
Chapter 1.1 pgs 6-9

2. Weather
Weather – the condition of the Earth’s atmosphere (temp, precipitation, humidity, wind, clouds) at a particular time and place.
Weather is different everywhere you go, and it is always changing!
Climate – the average conditions of the Earth’s atmosphere (temp, precipitation, humidity, wind, clouds) in an area

3. Atmosphere
Atmosphere – the envelope of gases that surround and protect the Earth.
The atmosphere appears to be very thick from our perspective, but is actually quite thin.
Atmosphere = avg 500 km
Earth’s radius (core to surface) = avg 6,000 km

4. Atmosphere Composition of Atmosphere Nitrogen (N2) – 78%
Oxygen (O2) – 21%
Carbon Dioxide (CO2) – 0.038%
Plus other trace gases
gases in very small amounts (argon, neon, helium, methane, krypton, hydrogen)
Can still have an important effect on Earth’s climate and human health!
Water vapor – water is gaseous form
Solid & liquid particles of dust, smoke, salt, and other chemicals

5. Composition of Atmosphere
Nitrogen (N2) – important to plant growth
Oxygen (O2) – important to animal life, we need to breathe oxygen!
Ozone (O3) – a form of oxygen
Pollutant in troposphere (poisonous)
Ozone Layer in stratosphere traps heat and protects against ultraviolet solar radiation

6. Composition of Atmosphere
Carbon Dioxide (CO2)
important to plants, necessary for photosynthesis
Traps heat in atmosphere
Too much CO2 is driving rapid climate change (global warming)
Water Vapor (H2O) – water in gas form
Causes clouds and precipitation (rain, snow)
Steam – tiny liquid water drops in the air

7. Composition of Atmosphere
Trace Gases – tiny amounts of different gases, but can still be important
Methane ( %) – a powerful “greenhouse gas” that traps heat in the atmosphere
Particles – tiny solid and liquid particles of dust, smoke, salt, and other chemicals
Can be serious pollutants
Can be added to atmosphere by nature or by man

8. Atmosphere Our atmosphere is important because
Provides oxygen, and other necessary gases, for life to survive
Traps heat to keep us from freezing, and to keep water liquid
Protects the surface from meteors and dangerous solar radiation