The Project

Descent Into the Icehouse

Transitions between greenhouse and icehouse states tend to be rapid, with dramatic consequences for life on Earth. The most recent of these fundamental climate transitions began around 50 million years ago and culminated at ~34 million years ago at the Eocene/Oligocene boundary with the rapid growth of the Antarctic Ice Sheet. Due to the nature of the rock record, this most recent transition is the best studied and most well documented of the greenhouse to icehouse switches, but nonetheless the processes responsible are still much debated. The most popular, but not the only, hypothesis is that it was caused by a decline in the atmospheric CO2 – an important greenhouse gas.

By burning fossil fuels, CO2 concentrations may reach values typical of the greenhouse world of the Eocene by the end of this century. It is therefore becoming imperative to better understand the role of CO2 in driving these natural cycles of Earth’s climate. Consequently, the principal aim of this project is to determine the main driver of this most recent and dramatic switch in climate state.

Climate is very complex; therefore, to achieve our goal, we are using a multidisciplinary approach that has aspects of both new data collection and sophisticated computer models. By combining computer simulations of the past with the generated new data we will be able to isolate which of the myriad of potential processes was responsible for triggering this fundamental shift in climate and better determine how they impacted the evolution of life.