Mechanisms of Past Climate Change
16:375:553
3 credits

Wednesdays and Fridays, 9:15-10:35 AM
Room 223, ENRS Building, Cook Campus

Course description
Grading
Class schedule
Papers to be discussed

Online essays on reading scientific papers
Final projects

Course Description

The geological record contains evidence of substantial changes in climate during Earth’s distant past. Identifying the mechanisms responsible for these changes can provide insights into fundamental climate system processes. This course will focus on four questions, each of which is at the forefront of contemporary climate research:

1)     How are periodic fluctuations in Earth’s climate related to slow changes in the shape of Earth’s orbit?
2)    How sensitive is Earth’s climate to radiative forcing?
3)     Did changes in the ocean’s overturning circulation cause millennial-scale climate variability?
4)     Was tropical Pacific climate variability (e.g., El Nino) different in Earth’s past?

Each of these questions will be addressed through a combination of traditional lectures, readings from the scientific literature, and group discussion. There are no formal prerequisites for the course, but some preparation in atmospheric science, physical oceanography, paleoceanography, physical geography, or geology is strongly recommended.

Grading

An important objective of this course is the development of critical thinking. Your grades will be determined by how well you can convince me of (1) your ability to think critically and (2) your ability to communicate your ideas to others, both in speaking and in writing. Your success will be evaluated based on your performance in the following categories:

Class participation
    Discussion leader: 20%
    Open discussion: 20%
Synthesis papers (for each of four topics): 40%
Oral presentation of final project: 20%

Class and assignment schedule

September 5 Course overview
September 7, 12 Lectures: Orbital forcing of climate
September 14 Discussion: Raymo and Nisancioglu (2003)
September 19 Discussion: Huybers and Wunsch (2005)
September 21 Discussion: Kawamura et al. (2007)
September 26 Discussion: Muller and MacDonald (1997)
September 28, October 3 Lectures: Estimating climate sensitivity from past climates
October 3 Synthesis paper 1 due
October 5 Discussion: Hoffert and Covey (1992)
October 10 Discussion: Lea (2004)
October 12 Discussion: Crowley (2000)
October 17 Discussion: Oerlemans (2005)
October 19, 24 Lectures: Climate variability on millennial time scales
October 26 Synthesis paper 2 due
October 26 Discussion: Zhang and Delworth (2005)
October 31 Discussion: Weaver et al. (2003)
November 2 Discussion: Alley et al. (2001)
November 7 Discussion: Rohling et al. (2004)
November 9, 14 Lecture: Tropical Pacific variability
November 14 Synthesis paper 3 due
November 16 Discussion: Clement et al. (2000)
November 21 Discussion: Wara et al. (2005)
November 28 Discussion: Koutavas et al. (2002)
November 30 Discussion: Stott et al. (2002)
December 5 No class today
December 7 (note: class starts at 8:20) Synthesis paper 4 due; Oral presentations of final projects
December 12 Extra meeting time (in case we need it)

Papers to be discussed

Most of the papers to be discussed are available online through the Electronic Journals web page maintained by the Rutgers University Libraries. The Resources web page of the Center for Environmental Prediction is a good place to start for information about the RU library system. Not all journals are available electronically; more specifically, AGU journals are not available through the Rutgers system. (AGU members can access papers from AGU journals published prior to the current year by following the link for that journal from the AGU Publications web page.) In a small number of cases, you may have to resort to using the library the old-fashioned way. (Sorry!)

Alley, R. B., S. Anandakrishnan, and P. Jung, 2001: Stochastic resonance in the North Atlantic. Paleoceanography, 16, 190-198.

Clement, A. C., R. Seager, and M. A. Cane, 2000: Suppression of El Niño during the mid-Holocene by changes in the Earth's orbit. Paleoceanography, 15, 731-737.

Crowley, T.J., 2000: Causes of climate change over the past 1000 years. Science, 289, 270–277.

Hoffert, M.I. and C. Covey, 1992: Deriving global climate sensitivity from paleoclimate reconstructions. Nature, 360, 573-576.

Huybers, P., and C. Wunsch, 2005: Obliquity pacing of the late Pleistocene glacial terminations. Nature, 434, 491-494.

Kawamura, K., et al., 2007: Northern Hemisphere forcing of climatic cycles in Antarctica over the past 360,000 years. Nature, 448, 912-916.

Koutavas, A., J. Lynch-Stieglitz, T. M. Marchitto, Jr., and J. P. Sachs, 2002: El Niño-like pattern in ice age tropical Pacific sea surface temperature. Science, 297, 226-230.

Lea, D.W., 2004: The 100,000-yr cycle in tropical SST, greenhouse forcing, and climate sensitivity. J. Climate, 17, 2170-2179.

Muller, R. A., and G. J. MacDonald, 1997: Glacial cycles and astronomical forcing. Science, 277, 215-218.

Oerlemans, J., 2005: Extracting a climate signal from 169 glacier records. Science, 308, 675-677.

Peterson, L. C., G. H. Haug, K. A. Hughen, and U. Röhl, 2000: Rapid changes in the hydrologic cycle of the tropical Atlantic during the last glacial. Science, 290, 1947-1951.

Raymo, M. E., and K. Nisancioglu, 2003: The 41 kyr world: Milankovitch's other unsolved mystery. Paleoceanography, 18, doi:10.1029/2002PA000791.

Rohling, E.J., et al., 2004: Similar meltwater contributions to glacial sea level changes from Antarctic and northern ice sheets. Nature, 430, 1016-1021.

Stott, L., C. Poulsen, S. Lund, and R. Thunell, 2002: Super ENSO and global climate oscillations at millennial time scales. Science, 297, 222-226.

Wara, M.W., A.C. Ravelo, and M.L. Delaney, Permanent El Niño-Like Conditions During the Pliocene Warm Period. Science, 309, 758-761.

Weaver, A. J., O. A. Saenko, P. U. Clark, and J. X. Mitrovica, 2003: Meltwater pulse 1A from Antarctica as a trigger of the Bølling-Allerød warm interval. Science, 299, 1709-1713.

Zhang, R., and T. L. Delworth, 2005: Simulated tropical response to a substantial weakening of the Atlantic thermohaline circulation. J. Climate, 18, 1853-1860.

 

Online essays on reading scientific papers

Simon Hunt, University of Oxford, “Reading Scientific Papers” (based on PowerPoint talk)
http://users.path.ox.ac.uk/~svhunt/internal/Grads/Reading_Scientific_Papers_files/frame.htm

John W. Little and Roy Parker, University of Arizona, “How To Read A Scientific Paper”
(life sciences perspective; good section on evaluating a paper)
http://www.biochem.arizona.edu/classes/bioc568/papers.htm

Elizabeth Willott, University of Arizona, “Reading a Scientific Paper”
(good section on how to read papers for different purposes)
http://research.biology.arizona.edu/mosquito/willott/proj/Survive/paper.html

 

Final projects

The final project will consist of a 15-minute presentation that discusses and critically evaluates a particular mechanism of past climate change. The mechanism that you choose to evaluate should be one that we have discussed in class (or one that is closely related). Time limits will be strictly enforced! These presentations will be similar in length to those typically given at large national meetings (e.g., American Geophysical Union, American Meteorological Society), so it will be good experience to learn how to organize your thoughts in a concise manner.

Student Topic Presentation Date