Review for Midterm 1

* indicates material that is not necessarily covered in the textbook but was discussed in class and or lecture notes

Disclaimer: I cannot guarantee this review covers everything that will be on the test.


You will be given the following list of equations (with real symbols)

Feedback factor              f = Delta Teq / Delta To
Inverse Square Law       S = So (ro/r)2
Wien's law               lambda-max = 2898 / T
Stefan-Boltzmann Law      F = sigma T4
Planetary Energy Balance sigma T4 = S (1-A)/4
Climate sensitivity     lambda = Delta Teq / Delta F (different 
                           lambda than in Wien's law)


Chapter 1 (and/or lecture)

Definitions:
  1. Greenhouse effect (why is it not like a blanket or greenhouse)
  2. Global warming
  3. Climate Change
  4. Biodiversity
  5. K-T Boundary
  6. Faint Young Sun Hypothesis
  7. Gaia
Concepts:
  1. What are the anthropogenic sources of CO2 given in Ch 1
  2. For CO2, global temperature, and ozone (excluding ice cores records), know generally how they are measured, how long are the records, and what are the sources of error.
  3. Why is there a plateau in the global temperature from about 1940-1970?
  4. RE fig 1-9: Roughly when are the glacial periods and where are the interglacial periods? What is the relationship between T, CO2, and CH4 in the ice core? What does their relationship mean (eg T affects CO2 and CH4 and vice versa)? Know the explanation given in ch 1 for how the variables are measured in ice cores.
  5. What causes changes in solar luminosity? How has solar luminosity changed in the last 4 billion years?
  6. You do not need to memorize the geological time scale, just be aware that they are cataloged by Eon, Era, Period, and Epoch, with generally diminishing duration.
  7. Know that the continents drifted. Usually it takes about at least 50 million years to notice much difference (for climate purposes).
  8. *What is the difference between weather and climate?
  9. *What are sources of uncertainty in predicting climate?
Chapter 2 (and/or lecture)

Definitions:
  1. Systems approach
  2. *Reductionists approach
  3. Component
  4. Coupling
  5. Feedback loop
  6. Thermal equilibrium
  7. Planetary albedo
  8. Surface albedo
  9. Self-regulating
  10. Optimum temperature
Concepts:
  1. Know how system diagrams work, using the methods of Ch 2. Do not indicate a sense of change in the components.
  2. Know how to use a system diagram to describe how each component will respond (ie increase or decrease) to a perturbation or force.
  3. Be able to graph A versus B, given the coupling relationship of A and B. For example if you were told an increase (or decrease) in daisy coverage causes a temperature decrease (or increase), you should be able to draw fig 2-7.
  4. Know that when the slope of a curve changes from positive to negative, the coupling must also change sign (see fig 2-9)
  5. Given figure 2-10a (not necessarily with part b attached), be able to identify the stable/unstable intersections and explain why they are stable/unstable (which has negative/positive net feedback).
  6. *Understand concept of a feedback factor using the revised definition given in class for Delta To
Chapter 3  (and/or lecture)

Definitions:
  1. Electromagnetic radiation
  2. Wavelength and frequency
  3. Flux
  4. Astronomical Unit AU
  5. Kelvin scale
  6. Blackbody radiation
  7. Effective radiating temperature
  8. Troposphere
  9. Stratosphere
  10. Convection
  11. Conduction
  12. latent heat
  13. sensible heat
  14. Atmospheric window
  15. Saturation vapor pressure (discussed in Chap 4, but belongs here)
Concepts:
  1. Wavelength is inversely proportional to frequency and frequency is proportional to energy
  2. The relative wavelength of the radiation we talked about are:
  3. UV < Visible < IR ( < = "is less than")
  4. Know how to use the inverse square law to compute the solar flux at some distance away from the sun
  5. The flux of radiation emitted by a blackbody reaches its peak radiation at a wavelength that depends on it temperature. Hence the sun emits at a lower peak wavelength than Earth
  6. The energy flux of radiation emitted by a blackbody is related to the fourth power of the temperature
  7. From the previous statement, we know that the sun emits a whole lot more energy than Earth. Why don't we fry?
  8. What is FIN-FOUT = ?, averaged globally when a planet's energy budget at the top of the atmosphere is in balance?
  9. Explain the factor of 4 on the r.h.s. of the equation for planetary energy balance
  10. Know how to use planetary energy balance to compute TE
  11. The magnitude of Earth's greenhouse effect is 33 C
  12. The major greenhouse gases
  13. The major atmospheric constituents
  14. Pressure depends on the mass of the atmosphere above it, so naturally it decreases with height.
  15. Why does Fig 3-9b exhibit all those curves? Or rather where is Earth's atmosphere heated most by the sun and why?
  16. *How do clouds form?
  17. Why are clouds important?
  18. Know the competing effect of clouds in terms of LW and SW radiation
  19. Which of the competing effects dominates for low stratus clouds and for high cirrus clouds?
  20. Which clouds (low or high) have a greater warming effect at night, compared to a cloud-free night?
  21. Scientists aren't sure about the sign of the cloud-temperature feedback loop yet.
  22. *How does the feedback factor (and stability) depends on the sum of feedbacks
  23. Know how to diagram the feedback loops in Fig 3-20, 3-21, and 3-22
  24. *At present the Earth is not in perfect radiative balance, planetary energy balance is off by about 1 W/m2. The consequence of this imbalance is that we are due for about another 1 deg C of warming if we emit no more greenhouse gases. We call this warming in the "pipeline" or warming "commitment".
Chapter 4  (and/or lecture)

Definitions
  1. Buoyancy
  2. Convergence/Divergence
  3. ITCZ
  4. Coriolis Effect/Force
  5. Continentality
  6. Advection
Concepts:
  1. Variations of incoming solar radiation with latitude Fig 4-1
  2. What latitudes receive a net radiation deficit/surplus? What compensates for the deficit/surplus to maintain thermal equilibrium?
  3. What drives the Hadley circulation and what are its characteristic features? How does latent heat release boost the circulation?
  4. Explain the Coriolis effect for motions that are initiated in north or south direction (not east-west)
  5. Describe the polar front zone and explain its slope
  6. Describe the source of the jet stream and geostrophic winds. Why is the jet stream where it is? On a day-to-day basis it is wavy because of atmospheric waves (I know that is redundant, but its good enough).
  7. What causes the seasons? Where is the greatest range in seasons? Why?
  8. How different is the solar flux at perihelion and aphelion? Why is this variation in solar flux not the cause of seasons in the northern hemisphere?
  9. What are the land-ocean contrasts in thermal inertia and albedo? What are the consequences for temperature and circulation on the diurnal and seasonal cycles?
  10. Where does it rain most? Where are Earth's deserts?

Chapter 5  (and/or lecture)

Definitions:
  1. Ekman spiral
  2. gyre
  3. pycnocline
  4. thermocline
  5. halocline
Concepts:
  1. What causes oceans to circulate? Where is the driving source? What are the consequences of heating the ocean from above?
  2. How do gyres get their shape? Answer at the level given in lecture notes and class. (Reading p 89-90 is only for those who enjoy suffering and is not recommended) Know the consequences of the gyre distortion.
  3. How do gyres transfer heat in the horizontal direction?
  4. What is an Ekman spiral? There is net transport to the right of the wind
  5. Ekman transport in the gyres distorts the surface height and creates a secondary circulation with upwelling/downwelling. The variation in surface height produces a pressure gradient force under the surface, which when balanced by the Coriolis force creates a gyre circulation beneath the surface in the same direction as the surface winds
  6. How does Ekman transport affect coastal upwelling and downwelling? What about upwelling along the equator?
  7. How is upwelling and downwelling related to the nutrient supply? What is the role of phytoplankton?
  8. The polar oceans are known to be sights of downwelling, which does not supply nutrients to the surface. However, they also experience relatively deep mixing which is a source of nutrients.
  9. What are the major ways the ocean affects climate?
  10. Know the general shapes of the curves in fig 5-6 (don't worry about numbers, instead you should know for example that the density increases with depth, a lot near the surface and less so with depth)
  11. What would happen to the ocean temperature at depth if all vertical circulation in the ocean ceased?
  12. *How does sea ice influence the ocean?
  13. Where and how are the major sources of deep/bottom water formed? In this class, we won't differentiate between bottom water and deep water. (Oceanographers would be scandalized, so don't tell any)
  14. Know how the major atmospheric and oceanic circulations contribute to heat transport