Integrated Assessment

• methane ch4
• nitrous oxide
• halocarbons 
• ozone o3
• aerosols 

• direct: cooling effect by breaking O2
• indirect effect: depletes stratospheric ozone (o3)

• chlorine as catalyst, destroys next O3 in O2 
• long lasting process destroying ozone shell 

• direct effect: scattering and absorption of solar and infrared radiation
• indirect effect: changes cloud properties 
• net cooling effect 

release of stored enery by oxidation of glucose

input: sugar, water, co2

output: energy 

carbon initially accumulated through photosynthesis minus plant respiration 

when there is more CO2 there is more pressure in the air

the stomatal pores of the plan will get smaller, so less warer esapces through evaporation

• heterothrophic (vs autotrophic): other organisms breathe out co2 taken in by the plant
• comes from organisms eating dead plants and releasing co2
• global warming: more decay of organic material, more flow of co2 to atmosphere 

• rising co2 concentrations = higher NPP because
  • inreased water used efficiency
  • increased photosynthesis
• compensated by 
  • saturation effect 
  • counter effect of heterotrophic respiration

Vegetation goes from carbon sink to carbon source 

• gas exchange in surface layer of ocean 
• atmospheric co2 pressure
  • low: ocean outgases co2
  • high: ocean dissolves co2 

• ocean as 
  • co2 source: warm ascending water
  • co2 sink: cold saline and descending water 

• temperature (bigger take up in low t°)
• salinity
• air pressure
• wind-induced mixing
• chemical reactivity 

• after physical dissolving, co2 removed by chemical process
• dissolved co2 reacting w water = carbonic acid
• carbonic acid dissociates in carbonate ion and hydrogen 
• once co2 dissolved, makes space for further co2 in surface 

co2 intake reduces concentration of carbonate ion bc uses them out, makes it harder to dissolve more co2 

less intake of co2 from atmosphere 

organisms use co2 for photosynthesis and release it w respiration 

dead organisms are decomposed in deeper ocean, releasing carbon

some sedimentation 

• carbon reservoirs are divided in 3 different stocks 
  • atmosphere
  • ocean
  • biosphere 

• reflected by clouds abd ground 
• absorbed by dark clouds or transferred into heat
• rest hits earth surface and is absorbed 

• blocked by ghg
• constantly absorbed and re-emitted 
• goes from earth to atmosphere and back 

• accumulation of radiation stops once re-emissions triggered a warner ground delivering outgoing infrared radiation equal to incoming solar radiation 
• as long as we add ghg, the t° will increase to catch up and achieve equilibrium 

• molecules of ghg atoms move : bond strectching and bond bending 
• radiation energy motivates this movement 
• when movement stops, energy leaves molecule, released via infrared radiation in all directions 
• absorptivity of radiation from diff ghg is unequally distributed along frequency wavelenght spectrum of radiation 

quantity of energy going through the gas 

0% = total absorption / 100% = no absorption 

• change in the net vertical irradiance at the top of the troposphere due to internal or external change 
  • ex change in concentrations of co2 (internal) or output of sun (external) 
• initial perturbation in earth's radiative energy budget, without allowing climate feedbacks to change troposphere t°
  • all properties of troposphere held fixed at unperturbated values 

• change in balance between 
  • radiation coming in atmosphere
  • radiation coming out of atmosphere 
• -> change in equilibrium 
  • negative: cooling effect
  • positive: warms atmosphere 

• most focring agents: co2, ch4, n2o
• albedo changes due to land use changes
• ozone depletion cooling effect
• sulfate aerosols
• ground change and surface dust 

concentration of co2 that would cause the same amount of radiative forcing as a given mixture of co2 and other ghg 

ratio of radiative forcing from release of 1kg of a substance relative to 1kg of co2 

• water vapor feedback: co2 increase = t° increase = water vapor increase = t° increase
• cloud radiation feedback: co2 increase = t° increase  = water vapor increase = cloud increase 
• cloud cover feedback
  • uncertain: t° increase or decrease 

surface t° increase = sea ice decrease = albedo decrease = surface t° increase 

sea ice decrease = open ocean increase = evaporation increase = low clouds increase = albedo increase 

equilibirum change in global mean temperature following doubling of the atmospheric equiv CO2 

considers processes on earth 

3d grid to describe local processes from bottom ocean to top atmosphere, lagitude and longitude 

• parts 
  • single atmospheric box
  • surface layer (land and ocean)
  • deep ocean
• influence
  • of solar and infrared radiation 
  • air-sea heat exchange
  • deep ocean mixing (upwelling)
  • + sinking of cold water (pumping mechanism) 

• more simplified approach
• considers
  • mean temperature
  • ocean heat capacity
  • perturbation of radiation energy balance 
  • feedback summarized by t° response parameters