Mechanisms of Past Climate Change
3 credits

Mondays and Wednesdays, 2:15-3:35 PM
Room 334, ENRS Building, Cook Campus

Course description
Learning goals
Class schedule

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 sensitive is Earth’s climate to radiative forcing?
2)   How are periodic fluctuations in Earth’s climate related to slow changes in the shape of Earth’s orbit?    
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.

Learning goals

1)  To improve critical thinking skills by carefully reading and evaluating peer-reviewed research papers.
2)  To improve scientific writing skills by summarizing and synthesizing the content of research papers discussed in class.
3)  To improve public speaking and presentation skills by presenting results from a course project.
4)  To develop a conceptual understanding of the mechanisms thathave been involved in past changes in climate.


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

January 23 Course overview
January 28 Lecture: Estimating climate sensitivity from past climates
January 30                (continued)
February 4 Discussion:  Lea (2004)
February 6 Discussion:  Kohler et al. (2010)
February 11 Discussion:  Schmittner et al. (2011)
February 13 Discussion:  Rohling et al. (2012)
February 18 Lecture: Orbital forcing of climate
February 20                (continued)
February 25 Discussion:  Hays et al. (1976) Synthesis paper 1 due
February 27 No class
March 4 Discussion:  Wang et al. (2008)
March 6 Discussion:  Raymo and Nisancioglu (2003)
March 11 Discussion:  Huybers and Wunsch (2005)
March 13 Discussion:  Marcott et al. (2013)
March 25 Lectures: Climate variability on millennial time scales
March 27      (continued) Synthesis paper 2 due
April 1 Discussion:  Broecker et al. (1985)
April 3 Discussion:  Zhang and Delworth (2005)
April 8 Discussion:  Alley et al. (2001)
April 10 Lecture: Tropical Pacific variability
April 15                (continued) Synthesis paper 3 due
April 17 Discussion of final presentations
April 22 Discussion: Clement et al. (2000)
April 24 Discussion:  Stott et al. (2002)
April 29 Discussion:  Koutavas+Joanides (2012)
May 1 Discussion:  DiNezio et al. (2009)
May 6 Oral presentations of final projects Synthesis paper 4 due

Online essays on reading scientific papers

John W. Little and Roy Parker, University of Arizona, “How To Read A Scientific Paper”
(life sciences perspective; good section on evaluating a paper)

Elizabeth Willott, University of Arizona, “Reading a Scientific Paper”
(good section on how to read papers for different purposes)


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.