Introduction

About Lesson 5

In this lesson, we will continue with our investigation of climate models. We will investigate more complex models of the climate system than in the previous lesson. We will first investigate a slightly more complex version of the EBM encountered in Lesson 4, where we explicitly insert an atmospheric layer above the Earth's surface. We will consider models that represent the full three-dimensional geometry of the Earth system, and model atmospheric winds and ocean currents, patterns of rainfall, and drought, and other key attributes of the climate system. We will also explore the concept of 'fingerprint detection'—a method that allows us to compare model predictions against observations to discern whether or not the signal of anthropogenic climate change can already be detected.

What will we learn in Lesson 5?

By the end of Lesson 5, you should be able to:

• Describe the hierarchy of theoretical climate models, the underlying assumptions, caveats, and strengths and weaknesses of various climate modeling approaches;
• Discuss both the strengths and limitations of current-generation climate models;
• Speak to the issue of how climate models have been 'validated';
• Assess the relative roles of human vs. natural impacts on climate, based on experiments with climate models;
• Assess the state of our current knowledge regarding the equilibrium climate sensitivity of Earth.

What will be due for Lesson 5?

Please refer to the Syllabus for specific time frames and due dates.

The following is an overview of the required activities for Lesson 5. Detailed directions and submission instructions are located within this lesson.

• Read:
  • IPCC Sixth Assessment Report, Working Group 1 --  Summary for Policy Makers (link is external)
    • Possible Climate Futures: p. 12-23
  • Dire Predictions, v.2: p. 36-37, 100-101, 110-111, 148-149
• Problem Set #4

Questions?

If you have any questions, please post them to our Questions? discussion forum (not e-mail), located under the Home tab in Canvas. The instructor will check that discussion forum daily to respond. Also, please feel free to post your own responses if you can help with any of the posted questions.