Climate Change through Geologic Time

Bob Raynolds
Denver Museum, Denver, CO

The Earth's climate has always changed and it continues to change. This set of graphs presents data obtained from a variety of climate proxies to illustrate climate changes over geologic time. Older data sets are derived from sedimentary rocks, younger data sets from ice cores, tree rings and finally, instrumental data. The data sets are presented as a sequential series of curves blown up by factors of ten; thus we can examine patterns over 100's of million years, over 10's of millions of years and so forth down to a decadal level. While we cannot use the past to predict the future, we can use the past to place the present in context. As geologists we hold the rear-view mirror depicting Earth's changing conditions. This marvelous perspective allows us to comment cogently on our current circumstance.

AAPG Search and Discovery Article #90092©2009 AAPG Rocky Mountain Section, July 9-11, 2008, Denver, Colorado