The atmosphere Flashcards
(74 cards)
CO2 composition
0.04%
Oxygen composition
21%
Ozone composition
0.000007%
Rare gases composition
1%
Nitrogen composition
78%
Thermal stratification
-The troposphere is warmed by the absorption of infrared energy emitted by the Earth. Temps normally
greatest near the surface, declining with altitude.
-The stratosphere is warmed by the absorption of UV light from the Sun. The temperature is lowest at the bottom of
the stratosphere, increasing with altitude.
Absorption of UV
Ozone layer (monatomic, diatomic, triatomic)
Delaying the escape of infrared energy
visible light -> heat -> emitted as infrared
Raises temps by:
-warm atmosphere emitting IR absorbed by earths surface
-warm atmosphere reduces heat loss by conduction from lands and oceans.
Ocean currents
wind blows over oceans -> creates currents -> distributes heat -> warm water to higher latitudes
Heat distribution
most suns energy absorbed at tropical regions -> warm surface heats atmosphere above -> heat distributed to higher latitudes by warm winds
Transport of water vapor
Winds transport water vapor to areas with little to no precipitation
Structure of the atmosphere
Thermosphere (highest altitude, lowest atmospheric pressure)
–Mesopause
Mesosphere
–Stratopause
Stratosphere
–Tropopause
Troposphere (lowest altitude, highest atmospheric pressure)
CO2 human activity
-combustion of fossil fuels
-drainage of marshes and bogs
-ploughing of soils
CO2 relative effects per molecule
1
Chlorofluorocarbons (CFCs) human activity
-Aerosol propellants
-refrigerants
-solvents
-expanded foam plastics
CFCs relative effect per molecule
25000
Tropospheric ozone human activity
-photochemical breakdown of NO2 and reactions with oxygen
Tropospheric ozone relative effects per molecule
2000
Oxides of nitrogen human activity
-Reacts at high temps in vehicle engines or power stations
-Fertiliser use
Oxides of nitrogen relative effects per molecule
160
Methane human activity
-Anaerobic respiration of microbes (paddy field, landfill, intestines of livestock)
-Formation of fossil fuels
Methane relative effects per molecule
25
Sea level rise
-Thermal expansion of water (expansion of water by heating is slow process due to high specific heat capacity of water and as the ocean is large and only surface layer is heated)
-Melting ice (only land ice adds to sea level rise as sea ice occupies the same volume when melted.
What are ocean currents caused by
-wind
-evaporation
-heating and cooling of water changes density
-changes in salinity