Abrupt climate and sea level change

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This PhD project will use numerical modelling to examine the causes and consequences of rapid climate and sea level change. Case studies from past deglaciations will be utilised to reach a new level of understanding for the link between ice sheet melting and sea level rise, rapid cooling, abrupt warming and the complete reorganisation of Atlantic Ocean circulation.At the Last Glacial Maximum (21,000 years ago), vast ice sheets stretched across much of the Northern Hemisphere. As climate warmed and the ice began melting, an intriguing and catastrophic chain of events was triggered: Largescale ocean circulation slowed, climate cooled, armadas of icebergs were released, sea level rose at an unprecedented rate, ocean circulation rapidly strengthened, temperatures suddenly increased by several degrees in a few decades...and then it all happened again just a few centuries later. Although well documented individually, we still do not know precisely how and even if these events are linked. Perhaps even more intriguingly, we know that many of the events have occurred repeatedly in Earth's past, suggesting there are consistent but currently unknown mechanisms in the Earth System for triggering abrupt climate change.The scientific community remains divided on the cause of the events, but there is consensus that the mechanisms are important to understand in order to predict when they will occur. As atmospheric CO2 rises in the coming years, and the Greenland and Antarctic ice sheets continue to melt, could these catastrophic events be triggered again?This exciting project will tackle this challenge directly, testing ice-ocean-atmosphere interactions that take place during deglaciations in order to produce seminal new knowledge on our climate. You will be at the heart of two international projects producing new model simulations and observational records of past abrupt climate change: The Paleoclimate Model Intercomparison Project (PMIP) Deglaciations Working Group and The International Union for Quaternary Research Focus Group on Deglaciations, both coordinated by Dr. Ruza Ivanovic. Thus, you will be granted access to the latest results and thinking from world-leading scientists, and, positioned at the forefront of international research into past warming climates, you will have the opportunity to feed into the global research agenda.PROJECT AIMYou will run and analyse complex numerical earth system models to examine the interplay between climate, ice sheets, icebergs and ocean circulation. You will compare the results from these simulations to observational records to evaluate model performance, verify/refute existing explanations for the events, and build and test new hypotheses. The overall aim is to establish the mechanisms that link ice, atmosphere and ocean in the Earth System, then explore the possibility that such rapid and catastrophic events as we know have occurred in the past will occur again in the future.