Conceptual Models of Global Climate for the Mid-Pleistocene Transition

Felix Pollak

Research Areas

Glaciology, Paleoclimatology

Project Brief

In the context of the ongoing greenhouse gas emissions in the atmosphere, it is of uppermost importance to examine the past in order to understand the behaviour of the climate system. An intriguing issue is the change in Earth’s climate response to orbital forcing during the ‘Mid-Pleistocene Transition’ (MPT), approximately 1 million years ago, when the dominant glacial/interglacial periodicity shifted from 40,000 years to 100,000 years. Various hypotheses have been proposed to explain this MPT, with one specifically focusing on the long-term cycle of CO2 in the atmosphere.

This PhD project aims to utilize conceptual models to simulate and explain the global climate evolution over the past 2 million years. These models are zero-dimensional representations of Earth’s climate system, which do not incorporate spatial representations based on the fundamental laws of physics, but instead include only a few variables that represent the most significant mathematical aspects of the global climate. Multiple formulations will be tested and the resulting models will be tuned onto observations, such as the global ice volume or atmospheric CO2 concentrations derived from paleoclimatic records.

The outcomes of this project will include:
1) a better understanding of the most important mathematical features driving the global climate evolution;
2) a better understanding of the causes of the MPT;
3) a deeper understanding of the mechanisms responsible for glacial-interglacial cycles, particularly the role of atmospheric CO2 variations;
4) a comprehensive curve depicting CO2 variations prior to the ice core era of the past 800,000 years.