The collapse of Atlantic circulation – what role for Greenland ice sheet melting?

One of the most pressing concerns for humanity is the potential imminent crossing of climate tipping points under a warmer climate. These tipping points include the rapid melting of Arctic sea-ice and the Greenland ice sheet, which in turn may trigger a collapse in the North Atlantic subpolar gyre (SPG) and the Atlantic meridional overturning circulation (AMOC). Current climate models do not simulate key processes accurately enough for us to have confidence in future projections of the SPG and AMOC. It is essential we obtain real-world empirical constraints on changes in the SPG and AMOC, and the associated forcing, from time periods most relevant to our future, i.e. from warm climate intervals. This PhD project will develop world-leading bench-mark records of the possible role of freshwater forcing in past changes in the AMOC and SPG during interglacial climates, including past abrupt interglacial events, changes during the industrial era, and comparison to ongoing present-day changes.  You will be trained in advanced geochemical methods including biogenic carbonate and sediment geochemistry (stable isotopes, minor/trace element ratios, rare earth element analysis), sedimentology, as well as analysing climate model outputs (option to explore running new simulations). Fieldwork opportunities include conducting sampling at international core-repositories, and likely opportunity to participate in an oceanographic cruise in the North Atlantic.