1. the result of the weight of a column of air pushing down on an area
2. air pressure is greatest at earth's surface because of gravity
1. a mixture of gases that surrounds the earth
2. contains oxygen, protects us from the sun and is always changing
1. coldest layer
2. temperature decrease as altitude increase
1.layered gases, thin air
2. ozone is in this layer
2. particles move fast and are far apart
3. temperatures can reach 1000 degrees Celsius
1. densest layer
2. 90% of atmosphere's mass
3. closest to earth - layer we live in
4 layers of atmosphere from lowest to highest:
What causes different temperatures at different altitudes?
the temperature is warm if the air contains gases that absorb solar energy
the temperature is colder if there are fewer of these gases
What is the atmosphere made up of?
the transfer of thermal energy by the circulation or movement of a liquid or gas
the transfer of energy by electromagnetic waves
the transfer of energy as heat through material.
it is absorbed by Earths surface
What happens to most of the energy from the sun?
What may cause global warming?
increase of greenhouse gases in the atmosphere
3 states of matter
solid, liquid, gas
a gradual increase in average global temperature
How are convection currents created?
warm air rises, cool air sinks
1. move short distances
2. caused by temperature differences
global winds blowing from the poles to 60 degrees latitude
winds that blow from 30 degrees latitude almost to the equator
blow toward the poles and carry moist air over the US
movement of air caused by differences in air pressure
The apparent curving of the path of winds and ocean currents due to the earth's rotation
separate bands of high and low pressure, found about every 30 degrees of latitude
the contamination of the atmosphere by the introduction of pollutants from human and natural sources.
1. pollutants that are put directly into the air by human or natural activity
2. examples: carbon monoxide, dust, smoke, chemicals
1. pollutants tht form when primary pollutants react with other primary pollutants or with naturally occurring substances such as water vapor
2. examples: ozone and smog
human-caused air pollution sources
1. transportation (largest source)
a. this could be reduced by driving hybrid cars that run
on both electricity and gasoline
2. industrial plants/power plants
3. indoor air pollution
Rain, sleet, or snow that contains a high concentration of acids
1. caused by CFCs
2. allows more UV radiation to reach Earth (this can cause skin cancer)