Review Sheet for Exam 2, Ice Ages Past and Present

This review sheet should not be taken as a complete review of the materials in this course.

Questions inspired by student E-mails:

1)Explain what a mass spectrometer does?

2) What is SMOW? What is it used for?

3)What is a dell number ( ), i.e. define it? What is it used for?

4)What is fractionation? How does fractionation of hydrogen and oxygen occur on earth?

5) What is the meteroic water line (i.e. Craig, 1961)?

6)What are the implications of the fact that the dell number ( ) for 018 is linearly related to mean surface air temperature (i.e.Dansgaard, 1964)?

7)What is the pelagic ooze (plankton scum) made of? What do plankton make that gets deposited on the seafloor?

8) What was the main difference between Dansgaard and Tauber/Shackleton/Craig/Olausson versus Emiliani on interpreting the ocean sediment isotopic record? [ You do not need to know these names, but I refer you to a table on page 9 of Dawson (class handout to be inserted between p. 123 and 124 of coursepack due to its unfortunate omission) ]

9)Why is PeeDee Belemnite (PDB) used as the standard for looking at O18 in ocean sediment cores and rock

formations?

10) How does weathering remove CO2 from the atmosphere? Does silicate weathering add or remove CO2 from the atmosphere? Does carbonate weathering add or remove CO2 from the atmosphere?

11) Explain how the development of the Himalayas (40 m.y.) may have caused global cooling leading to a glaciation? How does the Tibetan Plateau affect atmospheric circulation?

12) Explain how the burying of coal forests (300 to 340 m.y. ) might have induced a glaciation?

Some other questions (inspired by random, free association of the professor's brain):

13. How many neutrons does 18O have? 16O? How many protons?

14. Are glaciations common in Earth history?

15. What does the "sawtooth" pattern on ice cores and sediment cores indicate about climate?

16. Do glacial climates develop quickly or slowly? Do glacial climates end quickly or slowly?

17. Generally, where is air rising? falling? Where are the doldrums and horse latitudes? Is wind fast or slow there? Is it wet or dry there? Where are the trade winds? What direction do they blow? What latitudes are the "westerlies"? Which direction do they blow?

18. Lots of ocean currents, but to climate, the most important are the Gulf Stream and the Antarctic Circumpolar current. Which direction do they go and why? How might they impact climate?

19. What is the Coriolis force? What does it do?

20. How do continents affect atmosphere/ocean circulation? Why is the closing of the Isthmus of Panama (4 MA) significant? Why is the uplift of the Himalayas (40 MA) significant? (We only touched briefly on this in lecture, so I won't "hammer" these points, but think and learn about this one with respects to #17 and #18. Berner chapters are a great source of info.

21. What is the effect of an increase in CO2 in the Earth's atmosphere?

22. What is albedo? What volcanic substance contributes to changes in albedo?

23. Where is ozone helpful? harmful? (which "spheres")

24. Where is the best place to take an ice core? Why?

25. What does planktonic mean? Benthonic (a.k.a. Benthic)?

26. What are foraminifera?

27. What is vapor pressure? Relative humidity? Which has a higher vapor pressure, 18O or 16O?

28. What does Planck's law indicate? i.e. Which has higher energy, short wave (high frequency) or long wave (low frequency) electromagnetic radiation? Is incoming solar radiation principally higher or lower energy than outgoing terrestrial radiation?

29. What do snowlines (modern and paleo) indicate about climate?

30. Do all volcanic eruptions affect albedo? What is CCN?

31. What does "precession of the equinoxes" mean?

32. What are the "facts" that need to be explained in any theory about climate change and glaciation as evidenced from the rock record? the Ice core data? the Sediment core data? Snowline data?

33. What are the hypotheses for the facts (I wouldn't elevate any of them to theory status yet)? How good of a job do they do in explaining the facts?

34. What are the 3 cycles that make up a Milankovitch cycle (a.k.a. Milankovitch orbital process)?

35. What is eccentricity?

36. Does the earth's tilt vary with time?

37. What is thermohaline circulation (a.k.a. Wally Broecker's conveyor belt)? What change (i.e. at what time scale?) in climate may be controlled by themohaline circulation?

38. What is insolation? What solar phenomena is known to affect insolation?

39. Who do you trust that you're getting legitimate scientific information, Willi Dansgaard or Rush Limbaugh?