PhD position: How do atmospheric fluctuations stir the Atlantic Meridional Overturning Circulation?

This vacancy is the result of the collaboration between Utrecht University and NIOZ. The Department of Ocean Systems (OCS) at NIOZ (Texel) and the Institute for Marine and Atmospheric research, Utrecht University (UU) are looking for a PhD candidate with a strong interest in oceanographic measurements and modelling. The candidate should hold a master degree in climate science or a related subject. Experience with climate modelling and data analysis is a plus.

The project
The large-scale Atlantic Ocean circulation, also known as the Atlantic Meridional Overturning Circulation (AMOC), is a key component of the climate system. In the upper ocean the AMOC transports warm, saline tropical waters northward. At higher latitudes these waters are transformed to dense waters, which return southward in the deep ocean. Amongst other things, the AMOC plays a role in oceanic CO2 uptake and ensures that Northern Europe has a mild climate. There are concerns that the AMOC may weaken or collapse under global warming as a result of reduced water mass transformation.
However, the AMOC also shows considerable variability at time scales of weeks to years, which is assumed to be largely driven by atmospheric forcing fluctuations (wind, heat flux, freshwater flux). If large enough, these fluctuations can potentially “kick” the AMOC out of its current strong state and into an alternate, weaker, AMOC state.
As the PhD student, you investigate how atmospheric fluctuations affect AMOC variability, particularly in the North Atlantic transformation regions. For this, you will combine two tools: in situ observations and a high-resolution ocean model. The most important observational data will be the Overturning in the Subpolar North Atlantic Program dataset (OSNAP; co-led by NIOZ). You will participate in two research cruises (summer 2022 and 2024) and contribute to curating the data.
The high resolution ocean model, POP, will be compared against the observational data and used for a suite of model experiments to investigate the impact of certain atmospheric phenomena on AMOC variability.
The project will be jointly led by dr. Femke de Jong (NIOZ), who will supervise the observational work, and dr. Claudia Wieners (UU), who will supervise the modelling experiments. As the PhD student, you will work both at NIOZ-Texel and at Utrecht University.