Clues to Past Climate

Clues to Past Climate

leaves-somata-reichgelt-2016

This close-up of a Litsea calicarioides leaf’s stomata speaks to atmospheric carbon dioxide levels 23 million years ago. A new study authored by Lamont-Doherty Earth Observatory postdoctoral researcher Tammo Reichgelt and assistant research professor Billy D’Andrea used the ancient fossilized leaf, retrieved from a lake bed in New Zealand, to show for the first time that during this time, carbon dioxide levels increased dramatically over a relatively short period of time as Antarctic ice sheet began to deteriorate. The findings raise new questions about the stability of the Antarctic ice sheet today as atmospheric carbon dioxide concentrations rise to levels never before experienced by humans.

Photo: Tammo Reichgelt/Lamont-Doherty Earth Observatory