Climate Change in the Wild West Fifty Million Years Ago
Approximately 55 million years ago, the Earth experienced a massive, abrupt climate warming. A huge amount of gaseous carbon was released into the atmosphere, an amount approximately equal to what would be released if humans burned all the Earth’s known fossil fuel reserves. This event, named the Paleocene Eocene Thermal Maximum (PETM), raised global temperatures by up to nine degrees Celsius over a period of less than ten thousand years. Sea level rose, crocodiles lived in the Arctic, and there were palm trees in Wyoming (McInerney and Wing, 2011).