Cover Photo

Modeling Earth's Climate

Alan S. Thorndike and Casey J. Wall


Richard Feynman famously said that he did not fully understand the behavior of spin one-half particles because he could not communicate the ideas to freshman physics students. Like particle physics, you can learn a lot about the climate system by representing important physical processes as simply as possible. The goal of this workbook is to help students build intuition about climate using a series of ten simple models. The models were developed, by one of us, as part of a course, taken by the other, about climate and climate modeling at the University of Puget Sound. The models are kept as simple as possible, but their significance should not be overlooked. Many of the models are based on publications that are considered seminal works in climate science.

For each model, there is a description of the theory (PDF links) and example code (Excel links). To make the material accessible to as many students as possible, we use Excel for the example code. Of course, the models can also be written in a program other than Excel. For most models, the PDF file also shows observational data for comparison. All of the observational data are available for free download online, and links for data access are provided.

The progression of models in this workbook is such that only a few physical processes are treated at a time, but each model builds on ideas from previous ones. Model 1 introduces box models, Models 2-5 focus on the role of radiation in the climate system, and Models 6-10 include other important physical processes. With this being said, it is not necessary to work through the models in order. In fact, many will find it useful to pick a model or two to include in an introductory climate course as a supplement for pencil-and-paper problems. Those who jump into Models 6-10 may wish to reference Models 2-5.

Thanks for checking out this book. Please consider sending feedback to the contact address at the bottom of the page.


  1. Introduction to Box Models   PDF   Excel
  2. Black-body Radiation   PDF   Excel
  3. Distribution of Solar Radiation   PDF   Excel
  4. Zero-dimensional Model of Earth's Temperature   PDF   Excel
  5. One-dimensional Radiative Transfer in the Atmosphere   PDF   Excel
  6. Budkyo's Model   PDF   Excel
  7. A Minimal Model of Ice and Climate   PDF   Excel
  8. The Seasonal Cycle of Arctic Sea Ice   PDF   Excel
  9. Daisy World   PDF   Excel
  10. The Saltzman-Lorenz Equations   PDF   Excel

This work is licensed under a GNU Free Documentation License. This means that you are free to download, modify and distribute this work as much as you like. The one caveat is that if you modify the work and distribute the modified version, then you must apply the GNU Free Documentation License to the modified version so that others can benefit from your work.

Contact: caseyw8 at atmos dot washington dot edu

Cover photo: Clouds and sea ice over the Sea of Okhotsk in February, 2016 as observed by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Aqua satellite.

page last updated on 2016-11-25