geol midterm 1

  1. The earth formed approximately
    4.5 billion years ago
  2. The solar system formed approximately
    4.6 bya
  3. the atmosphere formed primarily
    by degassing of earth's mantle
  4. which 3 gases constitute most of the atmosphere near earth's surface?
    nitrogen, oxygen, argon
  5. where does the atmosphere's dioxygen come from?
  6. residence time is
    the time it takes to fill a reservoir, once emptied
  7. what is the residence time of CO2 in earth's atmosphere?
    400 yrs
  8. What is the residence time of H2O vapor?
    10 days
  9. What is the defining characteristic of of GHG?
    absorbs long wavelength radiation from earth's surface
  10. what are 3 most important GHG?
    water vapor, ozone, methane
  11. in a closed system, energy is always
  12. heat is
    the process of transferring energy through thermal contact
  13. which of the following modes of heat transfer requires physical medium?
    convection and conduction
  14. the moisture content of the atmosphere
    increases sharply with temperature
  15. why does anthropogenic CO2 matter for climate?
    it absorbs longwave radiation and has a long residence time in the atmosphere
  16. climate change always results from
    any long-term imbalance between incoming and outgoing radiation
  17. Stefan-Boltzman's law states that a physical body above the temperature of 0K emits an energy flux whose intensity varies
    as the fourth power of temperature
  18. Wien's displacement law states that
    hotter objects radiate at shorter wavelengths
  19. the earth receives ___ radiation from the sun, emits ___ radiation
    • shortwave
    • longwave
  20. which of these is not present in a beam of sunlight?
    near-infrared radiation
    long-wave radiation
    short-wave radiation
    electromagnetic radiation
  21. the planetary albedo is defined as
    the fraction of solar radiation reflected by the earth
  22. the poles are colder than the equator because
    the earth's curvature leads to beam spreading
  23. as the earth revolves around the sun, it experiences seasons because
    the earth's axis is tilted
  24. when are latitudinal insulation contrasts the greatest?
  25. the greenhouse effect is a popular term for
    the trapping of earth's outgoing longwave radiation due to GHGs
  26. what avg temp would earth be w/o an atmosphere?
  27. What is the earth's average temp?
  28. what planet is a dramatic example of "runaway greenhouse effect"?
  29. which process primarily explains the "runaway greenhouse effect"?
    water vapor feedback
  30. specific heat is defined as
    the quantity of energy required to raise 1kg of a substance's temp by 1K
  31. why is the ocean able to store so much heat?
    • 300x mass of the atmosphere
    • specific heat 4x dry air's
  32. in the climate system, thermal energy is defined as the sum of
    latent and sensible energies
  33. energy is measured in
  34. when do clouds form?
    • when a large amount of water vapor is added to an air parcel
    • when cooling lowers the saturation vapor pressure to the point where air parcels become saturated
  35. the pressure gradient force pushes air
    from regions of high pressure to regions of low pressure
  36. in the northern hemisphere, Coriolis force
    deviates air parcels to the right
  37. the unit measuring force named after which scientist?
  38. atmospheric pressure is a measure of the atmosphere's
  39. what is the effect of clouds on climate?
    it depends on the ratio from low vs high clouds
  40. what is the ultimate cause of the general circulation of the atmosphere?
    radiation imbalances b/w the tropics and high latitude
  41. on average, hadley cell best described
    • ascending motion near equator
    • descending motion near 30 degrees
    • surface easterlies
  42. poleward heat transport is accomplished by
    • hadley cell
    • wind-driven oceanic circulation
    • thermohaline circulation
  43. without poleward heat transport, the equator-to-pole temperature gradient would be
  44. what are the drivers of oceanic circulation?
    • density differences
    • wind stress
  45. why are the world oceans important to understand climate?
    • heat transport
    • heat storage
  46. what is the Ekman transport?
    wind-driven mass transport in upper ocean
  47. how is Ekman transport oriented with respect to wind (in southern hemisphere)?
    • 90 degrees
    • to the left
  48. what is thermohaline circulation?
    ocean circulation due to lateral differences in temperature and salinity
  49. why is thermohaline circulation important for climate?
    • it transports heat northward to the nordic seas, explaining why norway's coast is free of permanent sea-ice cover
    • it can play a role in abrupt climate change because of its sensitivity to freshening
    • it also carries CO2 into the deep, sequestering it from the atmosphere
  50. polewards of 20 degrees latitude, most of the heat transport is accomplished by the
Card Set
geol midterm 1