Card Set Information
Atmosphere is a thin layer of gas held to the planet by gravity.
composed of mainly nitrogen 78%, 21% oxygen, argon, and water.
Change in net(down minus up) atmospheric radiation at the top of the troposphere.
amount that earth is out of energy balance.
Greenhouse gasses increase longwave trapping by?
energy balance gets restored in outgoing longwave radiation through stefan boltzmann feedback.
Radiative forcing facts:
-GHG have positive radiative forcing
-CO2 has the largest radiative forcing of the anthropogenic GHGs
-Radiative forcing ΔTs= λΔF
What determines effectiveness of a GHG?
-concentration of gas in atmosphere
-frequency os absorption band relative to blackbody spectrum for earth
Carbon Cycle changes
-prior to the pre industrial revolution, a steady state was maintained.
-carbon cycle was balanced such that the distribution of carbon between reservoirs was not undergoing large changes.
-emission of CO2 by humans disrupted that balance
The amount of carbon released to the atmosphere has been increasing (1.9 ppmv/yr)
Anthropogenic emissions are 130x greater than volcanic emissions:
Natural sources and anthropogenic sources of carbon emissions
N = Forest fires, volcanic eruptions
An = combustion of fossil fuels, deforestation
-clearance of forests by logging and burning
-releases C stored in above and below ground biomass and in soils
-undisturbed forests hold 20-50 x more C than ecosystems that replace them
Forests cover what percent of land surface
-13 million hectares per year, equivalent to area of costa rica.
-20-25% of GHG emissions more than transportation emissions.
Fossil Fuel Combustion:
burning of fossilized organic matter to produce energy
Fossil Fuel combustion products /// sources
water, energy, carbon dioxide
electricity generation, transportation, industrial
exchange of carbon between earth's atmosphere, ocean, vegetation, and soil that occurs over days to thousands of years.
- carbon is not destroyed, but redistributed, on human timescales
conversion by plants of inorganic carbon to organic carbon
conversion by life of organic carbon to inorganic carbon.
incorporation of litter(dead plant leaves and roots) to soils.
escape of CO2 into the atmosphere through respiration/fermentation by plant roots, bacteria, fungi and soil animals.
Ocean atmosphere gas exchange
Exchange is driven by differences in co2
-co2 dissolves in water
-For every 10% increas in atmospheric co2 ,the surface ocean co2 will increase by 1%
co2 exchange b/t surface ocean and atmosphere is fast(~1 year)
physical and chemical processes that transport inorganic carbon from the ocean surface to interior
physical and biological process that transport organic carbon from the surface to interior.