gas

aerosol

component

property

increases towards the ground as the gravitational attraction of the planet pulls the gases and aerosols inward

the air has weight and it presses against everything it touches

air molecules have weight and take up place

air pressure is caused by the weight of all the air molecules in the atmosphere pressure down on the earth

humans live in the troposphere

nearly all weather occurs in this layer

most clouds appear here

lots of human activities take place within this region

air pressure drops with increasing altitude

temperature drops with increasing altitude

thin layer with high density

air pollution mostly happens in this layer

little convection and mixing happen in the stratosphere

temperature increases with increasing altitude

ozone layer exists in the stratosphere

lower temperature with higher altitude which results in convection

thickest layer in the atmosphere

sun radiation causes particles to be electrically charged

all living need some of the gases for life support

without the atmosphere,Earth would likely be the moon

atmospheric gases,especially carbon dioxide and oxygen are extremely important for living organisms

the atmosphere keeps earth's temperature within an acceptable range

consists of chemicals,particulates,biological materials or other harmful materials in to the Earth's atmosphere

mobile sources

stationary sources

area sources

naturally occur in our environment

significant but do not create ongoing air pollution problems like other source types

primary pollutant

secondary pollutants

aerosol pollutants

gaseous pollutants