Monday, January 18, 2012 CC-BY-NC
L3 - alternate

Maintainer: admin

Jan 18


-weather over time
-tropical: hot, humid
-poles: dry and cold

2Earth System

  • atmosphere - warm fronts, cold fronts, jetstreams, changes in precipitation
  • hydrosphere -- water from oceans: rain, snow, ice
  • biosphere -- living system, plants absorb co2, release water, oxygen. animals consume oxygen, release co2.

3stefan-boltzmann law

  • blackbody objects - hotter objects emit more radiation: $$ F, energy flux = a T^4 $$
  • i.e. if earth was twice as hot, it releases 16 times more energy

4energy balance - green house effect

  • green house gases - atmosphere absorbs most of the energy emitted by earth and that energy is radiated back down

5green house gases

  • make up a very small amount of atmosphere. most atmosphere is nitrogen and oxygen
  • water vapor, co2, methane, nitrous oxide, ozone in that order

6why are tropics warmer?

angle that the sunlight hits the earth - over poles, the same amount of energy is spread out over a larger distance


  • temperatures want to equilibrate - we have a series of cells
  • i.e. inner tropical divergence zone, is where two cells meet
  • understand how the precipitation works.

8coreoulius effect

  • the spinning earth creates drag that causes circulation of water and air
  • there are a lot of coupling between sea surface and coupling - strongest in tropics

9land vs ocean

  • they heat differently.
  • sun heats just the surface area of land - very little mass being heated
  • sun penetrates the water, a larger area. + there is mixing. slow heating, slow cooling (high 'inertia')

10conveyor belt effect

  • warm waters evaporate, caries of moisture and cools it, the salinity increases, the water becomes denser, and then sinks, and travels around the world, and then it comes up, due to some complicated factors (this circulation takes 500-1000 years).
  • it sinks around iceland
  • important because as greenland's ice sheet melts, the salty changes, which will fuck up some stuff

11orthographic precipitation

  • something about mountains

12new material

13System theory

  • system has sources, stocks, and sinks
  • amount in the reservoir is equal to the difference of the rate of change between the source and the sink

14example of how energy is transferred through the biosphere

  • 99.25% of energy of sun goes into heat and evaporation
  • 0.75% goes into 'gross primary production'
    • about a 3rd of that is used in plant respiring
  • some energy goes to roots, some amount goes to leaves

  • soil organisms receave a piece
  • insects mostly eat green stuff

15global carbon cycle/budget

  • carbon: second most common
  • most important: since human actives don't change amount of water vapor
  • mega, giga, tera, peda: peda = 10^15. measure things in peda grams of carbon/year
  • atmosphere: 590 (i think) pedagrams/year
  • atmosphere, oceans, lands all absorb carbon - check numbers
  • oceans are the largest store of carbon
  • marine biota: 3 pedagrams/year: but release and absorb 39 (storing: absorbing, dying, and settling to the bottom of the ocean)

16human impact of carbon budget

  • land use
  • net change: 3.3 pedagrams carbon/year added

17terrestrial carbon cycle

17.1carbon budget of photosynthesis

  • chlorophyll
  • create sugars
  • at night, absorbing water, realizing co2

18looking at changes over time and space: Equilibrium

  • balanced system

19Dynamic equilibrium

  • cold winter, hot summer

20dynamic dis-equilibrium

  • dynamic behavior over some other function. sine wave over a linear function