Global Change, fall 2010
Graduate level homework assignments
Grad Assignment 1. Assigned Aug. 31, due Sept 14: click here
Links to cited references:
Lean and Rind 2008, 2009
Keenlyside et al. 2008
Smith et al. 2007
Breakout Discussion 1, September 16
I'd like us to use this period to talk about short-term climate projections and their usability. This will key off of the assignment you did this past week - I'm expecting those papers will inform the discussion as well as the assigned reading.
Please read at least one of the following papers. These are both about the same level of difficulty.
Diffenbaugh and Ashfaq 2010: a climate modeling paper about future heat extremes in the west
Lemos and Rood 2010: A social science take on the usefulness of climate projections and the role of uncertainty
In preparation for the discussions, please prepare a brief (0.5-1 page) writeup of the paper you read that includes the following: (you should do this even if you are not attending the discussion - thanks).
1. What is the main point of the paper? What is its significance for the "big picture"?
2. What are the strengths of the paper? What are its weaknesses?
3. Provide 2 questions for further discussion in class.
GRAD Assignment 2. Due Oct. 5: click here
Links to cited references:
Davis et al. 2010
Hoffert 2010
Breakout Discussion 2, October 7
Let's use this period to talk about a key question in carbon-cycle climate studies: whether tropical forests (and in particular, the Amazon) are a net source or sink for atmospheric CO2. As we will review in the land-use change drivers lecture coming up, deforestation causes a source to the atmosphere. But could a small sink across the broad areas of primary forest integrate to balance this out? We will discuss the Houghton et al (2009) review of this question. Background reading on two different methods is also provided: tree inventories in forest plots (Gloor et al., 2009), and atmospheric measurements (Gatti et al., in review)
ASSIGNMENT: Houghton et al. (2009) The Regional Carbon Budget
BACKGROUND:
Gloor et al. (2009) Does the disturbance hypothesis explain the biomass
increase in basin-wide Amazon forest plot data?
Gatti et al. Vertical profiles of CO2 above eastern Amazonia suggest a
near neutral carbon balance between 2000 and 2009
As with the first breakout, to prepare for the discussions, please prepare a brief (0.5-1 page) writeup of one of these three papers that you read that includes the following: (you should do this even if you are not attending the discussion).
1. What is the main point of the paper? What is its significance for the "big picture"?
2. What are the strengths of the paper? What are its weaknesses?
3. Provide 2 questions for further discussion in class.
GRAD Assignment 3 . Due Oct. 26: click here
Links to cited references:
Breshears et al. 2005
Adams et al., 2009
Adams.09_exchange_PNAS.pdf (contains Leuzinger et al and Sala 2009).
Breakout Discussion 3, October 28
In this breakout we will continue to discuss the carbon sink question, but shift the focus from the terrestrial Amazon to the southern ocean, which has been approximately 40% of the ocean sink for anthropogenic CO2. The question is: has this sink been diminishing in recent years, and what will be its fate in the future?
We are privileged to be joined in this discussion by Assistant Professor of Geosciences Joellen Russell, whose research includes a focus on this interesting question.
ASSIGNMENT: LeQuere et al. (2007) Saturation of the Southern Ocean CO2 Sink Due to Recent Climate Change
Exchange between LeQuere et al and two sets of critics (Law et al. and Zickfeld et al)
Prepare a 1 page write-up summarizing:
(1) (first 0.5 page) the findings of LeQuere et al, which include two parts: (a) a kind of observation; and (b) a proposed mechanism to explain the observation (make sure to say where their inference about mechanism comes from).
(2) (second 0.5 page): the claims made by the critics, and LeQuere et al's response, focusing first on the issue raised by Law et al (pertaining primarily to the observation part of LeQuere et al.) and second, on that raised by Zickfeld et al (pertaining to inferences made about the mechanism and how it might change in the future).
Note: these papers include some fairly technical details about "inverse methods" for detecting carbon sinks and sources at the ocean's surface. If you find this part opaque or confusing, don't get bogged down, just focus on understanding the findings that are claimed to follow from the method.
FURTHER BACKGROUND
For more detail and background on the interesting question of mechanisms driving potential changes in the southern ocean carbon sink (touched on by the LeQuere et al exchange with Zickfeld et al.), see Russell et al (2006).
GRAD Assignment 4. Due November 23, 2010. Click here.
"Anticipating changes in Colorado River flow"
Grad breakout #4, Nov. 18.