ROSSETTA is a large multi-disciplinary and multi-institutional proj
Twenty-three million years ago, the Antarctic Ice Sheet began to shrink, going from an expanse larger than today’s to one about half its modern size. Computer models suggested a spike in carbon dioxide levels as the cause, but the evidence was elusive – until now. Ancient fossilized leaves retrieved from a lake bed in New Zealand now show for the first time that carbon dioxide levels increased dramatically over a relatively short period of time as the ice sheet began to deteriorate. The findings raise new questions about the stability of the Antarctic Ice Sheet today as atmospheric CO2 concentrations rise to levels never before experienced by humans.