UCAR logo

UCAR Office of Education and Outreach

Dr. Randy M. Russell

Randy Russell

Paleoclimate Proxies

Although we don't have any direct means for measuring, for example, the mean annual temperatures at various places in North America two million years ago, we do have indirect methods for estimating climatic conditions of the distant past. Such indirect clues about past climates are know as paleoclimate proxies, or proxy records. Just as Sherlock Holmes might infer the height, weight, and other telltale features of a suspect from a series of footprints, paleoclimatologists infer the climatic conditions of the past from tree rings, ice cores, layers of ocean sediments, and similar proxy evidence.

This course has several pages devoted to most of the major types of proxies commonly studied. As you read these pages, don't worry too much about specific details of each of the proxies. Instead, look for overarching trends and commonalities between the different types of records. Here are a few "study guide" pointers to keep in mind as you survey the types of proxy records:

The main types of proxies used to "measure" past climates are briefly described below. Click on each proxy to go to a page with a more in-depth treatment.

Last modified: 11 October 2010
Created: 6 October 2010