MT552 tasks for Physics of Climate

Term Paper

BACKGROUND

This paper should be a critical review of some topic involving climate modeling using simplified climate models. Here "simplified" means that the model used has averaging over at least one spatial dimension, such as the 0-D, 1-D (latitude) and 1-D (height) models studied in class. Other examples include zonally averaged latitude-height models and vertically averaged models with some degree of (perhaps crude) longitudinal as well as latitudinal variation. The latter, for example, might have land and ocean fractions at each latitude. Some of these models are often called Intermediate Models, since they are more complex than a 0-D model, but not so much as a full-blown GCM based on the primitive equations.

The virtue of these simpler models is that one might be able to examine process interactions in more detail and with greater control than in a GCM. They also tend to run much faster, allowing one to do more experimentation. They are, however, subject to limitations based on the assumptions used for formulate them.

TASK

You need to write a report giving a critical review of some usage of simplified models. Unless directed otherwise, you should focus on 2-4 papers by an author or group of authors that used (and perhaps developed) one of these model. The paper should be about 5 pages of text - that is about a GRL-length paper. By "critical", I do not mean that you simply attack assumptions and shortcomings, but demonstrate an understanding of what the paper contributed to the overall goal of understanding the climate system.

The paper should be structured like a published scientific paper (e.g., clear line of development, motivation and conclusions, citation of work by others, etc.) Among other things the report should include:

1. Introduction motivating the topic.
   • What is the climate issue the authors are exploring in this set of papers?
   • Why did the authors feel that this was a topic worth exploring?
   • Why was a simplified climate model appropriate or perhaps necessary (as opposed to a GCM)?

2. Description of the model, especially its assumptions
   • How did these assumptions limit what could be studied?
   • How did these assumptions make it easier to understand behavior of the model?
   • What methods were used to arrive at climate states studied (i.e., solutions) and to study the results (e.g., statistics, analytical manipulation of equations, graphics, etc.)

3. Discussion of the results produced
   • How was the model applied? Under what conditions (e.g., boundary conditions) was it used?
   • Since your evaluation covers more than one paper, what variations on a central theme were covered? How did assumptions change and what was gained or lost by changing assumptions?
   • What behavior emerged from the model?
   • What features of the behavior did the authors emphasize and what conclusions for the climate system did they draw from the behavior?
4. Intrepretation of results
   • This is where the "critical" aspect of the review is especially prominent. To what extent were the authors able to meet the goals (stated or implied) based on their motivations for doing the work?
   • Are there other ways they could have satisfied their motivations? For example, were all assumptions necessary?
   • Does the work set a foundation for further usage of this model (or some variant of it)?
   • How would you use results from this work to evaluate behavior of a more complex model, like a GCM?

Papers are due the last day of classes.

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