©2002 Donald Kahn
University of Minnesota
School of Mathematics


Richard McGehee





PaleoBudyko is a MATLAB program allowing the user to investigate the last five million years of climate data and Earth orbital parameters and compare them to the output of the Budyko model. The program consists of a MATLAB GUI (PaleoBudyko.m) and a data file (data.mat).

You can download the files here:


To run the program, type 'PaleoBudyko' at the MATLAB command line. Make sure that both files are in the MATHLAB path, preferably in the current directory.


Computation of the Milankovitch Cycles are due to Laskar et al, "A long-term numerical solution for the insolation quantities of the Earth," Astronomy & Astrophysics 428 (2004), 261–285.
The computations are posted on the Web at

Climate data are due to Lisiecki and Raymo, "A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records," Paleoceanography 20 (2005), PA1003.
The data are posted on the Web at

A description of Budyko's model and the computation of its stable equilibria can be found in McGehee & Lehman, "A Paleoclimate Model of Ice-Albedo Feedback Forced by Variations in Earth's Orbit," SIAM J. Applied Dynamical Systems 11 (2012), 684-707.
DOI 10.1137/10079879X

Last update: July 28, 2013 ©2013 Richard McGehee