Layers of the Atmosphere Flashcards
What is the atmosphere?
The layers of gases that surround Earth
Why is the atmosphere helpful?
- Allows us to breathe
- Holds in heat
- Protects us from harmful solar radiation, solar winds, meteros
What is the composition of air?
- Nitrogen = 78%
- Oxygen = 21%
- Other gases = 1%
What determines the layers of the atmosphere?
Tempeture
What is the troposphere?
- Contains all of the weather
- The sphere we live in - Dominated by convection cells and atmospheric pressure
What is air pressure?
Weight of the atmosphere pressing down on the surface
Why are there different pressures?
Different pressures are because of rising and falling air
What causes low pressure?
- Rising air
- Lower density
What causes high pressure?
- Sinking air
- High density
What happens when there is high pressure?
- Sinking air (more dense)
- Clouds cannot form
What happens when there is low pressure?
- Rising air (less dense)
- Clouds can form
What 3 factors affect air pressure?
- Elevation
- Temperature
- Humidity
What does elevation do to affect air pressure?
- The higher we go, the thinner the air gets
- Less air to assert weight
What does temperature do to affect air pressure?
- At the surface, high temperatures cause low pressure
What does humidity do to affect air pressure?
- Water vapor in the air can either increase or decrease air pressure
What is wind?
Air movement between one place to another (high to low)
What is land breeze?
- At night time
- Wind coming from the land
- Warm air rises (above water)
- Cool sinks (above land)
- Heat capacity holds onto heat all day long
What is sea breeze?
- Day time
- Wind coming from the water
- Warm air rises (above land)
- Cool air sinks (above sea)
- High heat capacity means water takes longer to heat up
