0-17 km above Earth's surface, site of weather, organisms, contains most atmospheric water vapor. (temperature decreases with increasing altitude, pressure decreases);contains 75% of atmospheric gases
stratosphere
12 to 50 km above Earth's surface,: contains ozone layer; absorbs UV ; temperature increases in this layer; weather balloons in this layer
mesosphere
50 to 100 km above Earth's surface; meteors burn up in this layer due to friction; temperature decreases in this layer; coldest layer; very few gas molecules
thermosphere
100-550 km above Earth's surface ; auroras occur here; temperature increases in this layer
exosphere
> 600 km above the Earth's surface; the outermost region of Earth's atmosphere; some hydrogen and helium; space; satellites found in this region
ozone
a gas molecule that is made up of three oxygen atoms
ozone layer
a layer in the stratosphere (at approximately 20 miles) that contains a concentration of ozone sufficient to block most ultraviolet radiation from the sun
UV radiation
energy from the sun that damages DNA structure, increases mutation rate, and causes skin cancer
aurora
an atmospheric phenomenon consisting of bands of light caused by charged solar particles following the earth's magnetic lines of force
air pressure
the force caused by the weight of a column of air pushing down on an area; decreases with altitude
altitude
elevation above sea level
nitrogen
the most abundant gas in Earth's atmosphere
acid precipitation
conversion of sulfur oxides and nitrogen oxides to acids that return to Earth as rain, snow, or fog; main cause burning fossil fuels especially coal-fired electric plants
greenhouse effect
natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases
global warming
an increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)
greenhouse gases
gases such as carbon dioxide, methane, nitrous oxide, water vapor, and ozone in the atmosphere which are involved in the greenhouse effect;
chlorofluorocarbons
group of chemical compounds used in refrigerators, air conditioners, foam packaging, and aerosol sprays that may enter the atmosphere and destroy ozone
50%
amount of Sun's energy that reaches Earth's surface
78%
nitrogen gas makes up this much of Earth's atmosphere
radiation
the transfer of energy by electromagnetic waves; travels through space
convection
the transfer of thermal energy by the circulation or movement of a liquid or gas
conduction
the direct transfer of heat from one substance to another substance that it is touching; contact