Welcome to ClimatePhys. Please see the Introduction and Blog Rules for an expanded version of the site’s purpose and intended readership. The goal of this site is to provide a technical forum for discussions of planetary climate, climate change, and the governing dynamics that ultimately dictates the behavior of atmospheres. Some attention will be given to the issue of modern-day climate change, although my mission is to focus on a broader class of issues that can be generalized to any time period or even some hypothetical planet. There are, however, a number of key events in Earth’s past that are worth mentioning specifically and I will do so when appropriate.