About the project
Polar amplification where enhanced warming in polar regions outpaces global temperature change is poorly understood. Using geological evidence, climate models and theory, this project will explore why past polar amplification sometimes affects the Arctic, sometimes the Antarctic and sometimes both poles. Projections of polar amplification for future climate change will be made.
Over the last century climate change has been fastest in polar regions, with warming in the Arctic occurring three times faster than the global average. This phenomenon, termed polar amplification, is also a robust feature during periods of climate change in the geological past, although the relative amounts of polar amplification in the northern and southern poles has varied. The Arctic and Antarctic regions are particularly susceptible to climate change, and the consequences of either polar ice melt, permafrost melting, or polar ecosystem reorganisation have global repercussions.
However, we still do not know which processes contribute most to polar amplification, or why it affects the northern and southern hemispheres differently during different geological periods. Processes including increased local climate feedbacks in polar regions, ocean and atmospheric circulation, and the increasing fraction of poleward heat transported through water vapour in a warming world may all have contributed to polar amplification in different relative amounts at different times.
In this project, the successful candidate will interpret geological archives using numerical climate models (e.g., Goodwin and Williams, 2023) and theory to quantify which processes dominate polar amplification, explain why the Arctic and Antarctic respond differently during different geological eras and make future projections. Several geological events will be explored, such as: the causes of Antarctic glacial onset; polar responses during Palaeocene-Eocene Thermal Maximum warming; Pleistocene glacial-interglacial cycles; continental uplift (Gernon et al., 2024); and the potential for snowball Earth inception. Future polar responses during the Anthropocene will also be explored over many timescales.