NERC-funded Ph.D. studentship in climate and ocean sciences at the University of Liverpool
Project title: Ocean circulation control of heat and carbon uptake
Supervisors: Prof. Ric Williams (Liverpool), Dr Phil Goodwin (Southampton), Dr Alessandro Tagliabue (Liverpool), & Prof. David Schultz (Manchester);
External supervisors and institution: Dr Jonathan Lauderdale & Prof. Mick Follows (MIT)
This studentship examines a fundamental question of how the ocean uptake of heat and carbon from the atmosphere are related to each other. There is a general expectation that the ocean uptake of heat and carbon
will increase and follow each other given the rise in atmospheric CO2 and the background warming of the climate system. We wish to assess how the ocean uptake of heat and carbon varies, and how they are related to each other, for different ongoing changes
in ocean circulation, including changes in the meridional overturning in the North Atlantic and Southern Ocean, and changes in the tropical circulation involving El Nino/La Nina cycles.
This project is motivated by the question of why global warming is nearly linearly proportional to carbon emissions, a central outcome of the IPCC  report. We have explained this response by assuming
that the global ocean uptake of heat and CO2 due to climate change is similar to each other [Goodwin, Williams & Ridgwell, 2015, Nature Geoscience]. However, what is unknown is how similar the ocean uptake of heat and carbon is for changes in ocean circulation,
such as changes in meridional overturning in the North Atlantic and Southern Ocean, or El Nino/La Nina cycles.
This project aims to investigate how the ocean uptake of heat and CO2 varies for changes in ocean circulation, including regional changes in ocean overturning and El Nino/La Nina states.
The plan of work for the student involves analysing the thermal and carbon responses of the ocean and climate system using a hierarchy of models, perturbed by changes in physical forcing.
Our research questions are:
* ocean heat and CO2 uptake are likely to be similar for the upper ocean involving gyre circulation;
* ocean heat and CO2 uptake are likely to differ for the deep ocean involving the overturning circulation, where there is an asymmetrical response in the Atlantic and Pacific.
The student will investigate the ocean heat and CO2 uptake for a range of physical perturbations, including changes in North Atlantic and Southern Ocean overturning, and in El Nino/La Nina cycles.
These physical perturbations will be applied to a range of simple to more complex models including
* 2 layer model of the ocean, where changes in upper ocean heat content will be assessed, and including a slab atmosphere to provide the radiative forcing;
* an efficient multi-layer ocean box model for an idealised global domain;
* a state of the art MIT ocean general circulation model, which we have used to explore how ocean overturning affects atmospheric CO2 on millennial timescales;
* the Fast Ocean Atmosphere Model, NCAR Community Earth System Model to explore ocean overturning and heat uptake in a coupled atmosphere and ocean model.
The outcomes of the work are relevant to a central question of the last IPCC report, which is why surface warming is linearly dependent on carbon emissions. In our view, this response is a consequence of the
how the ocean takes up heat and carbon [Goodwin et al., 2014, Nature Geoscience] and long-term dependencies of the climate system [Williams et al., 2012, GRL]. This project will test that assertion.
This work plan can be revised and modified according to the input and aptitude of the student.
The student will have the opportunity for an extended visit to project partners, Jon Lauderdale and Mick Follows at MIT, to gain skills in integrating the MIT GCM. Training in the idealised atmospheric-ocean
coupled model is provided by David Schultz at Manchester.
Our studentships are funded by NERC and are available to UK nationals and other EU nationals that have resided in the UK for three years prior to commencing the studentship. If you meet this criteria, funding
will be provided for tuition fees and stipend. If you are a citizen of a EU member state you will eligible for a fees-only award.
Applicants should have a strong academic track record with a science degree, such as including Ocean Sciences, Meteorology, Mathematics, Physics or Engineering. The project involves analysing data and integrating
ocean models, so that the student needs to have an aptitude for quantitative work.
Deadline: 4 February 2016