My research is addressing the following questions:



How the Gulf Stream affects the carbon cycle?

How the ocean takes up heat and anthropogenic carbon?

What happen to the climate system when net zero is reached?

Major projects

Leading a study of The Gulf Stream control of the North Atlantic carbon sink, referred to as C-Streams.

A combined observational field and modelling programme involving researchers at University of Liverpool, National Oceanography Centre, Southampton, Scottish Association of Marine Sciences and British Antarctic Survey, and University of Maimi supported by a £3.7M NERC-NSF large grant. Project partners include MIT, NORCE Norway,  University of Rhode Island and NASA.

Update for the fieldwork:

Postcard from Florida Current, University of Liverpool, 23 August 2023.


Examples of recent important papers include:


Williams, R.G., P. Ceppi, V. Roussenov, A. Katavouta and A. Meijers, 2023. The role of the Southern Ocean in the global climate response to carbon emissions. Philisophical Transactions A, Royal Society, 10.1098/rsta.2022.0062. Link


Demonstrates the similarities and differences between how anthropogenic heat and carbon are taken up by the Southern Ocean in idealised future climate projections.




• Williams, R.G., A. Katavouta and V. M. Roussenov, 2021. Regional asymmetries in ocean heat and carbon storage due to dynamic redistribution in climate model projections. J. Climate, doi: 10.1175/JCLI-D-20-0519.1. PDF


Demonstrates how anthropogenic heat and carbon anomalies can have opposing signs due to the effect of changing circulation.



• Williams, R.G., P. Ceppi and A. Katavouta, 2020. Controls of the Transient Climate Response to Emissions by physical feedbacks, heat uptake and carbon cycling. Environmental Research Letters, 15, doi:10.1088/1748-9326/ab97c9,  PDF



Reveals how intermodel differences in how warming increases with carbon emissions is mainly due to thermal responses linked to physical climate feedbacks and ocean heat uptake.




Research group and collaborations:


My research group includes research fellows, postdoctoral research associates and PhD students: 


• Dr Vassil Roussenov, a Research Fellow, an expert of numerical modelling, addressing heat content and sea level change, as well as nutrient cycling and transport;


• Dr Hemant Khatri, a researcher addressing how atmospheric forcing controls the subpolar North Atlantic ocean;


• Dr Ciara Pimm on subduction in the Southern Ocean (together with Andrew Meijers and Dan Jones, British Antarctic Survey). 


Previous 20 PhD students include:

     • Prof. Dr Guatliero Badin (previously Lecturer at Hamburg)

     .• Dr Clare Bellingham (researcher at National Oceanography Centre)

     • Dr Kate Day

     .• Dr Phil Goodwin (Associate Professor at Southampton, previously NERC fellow at Cambridge),

     .• Dr Rob Hall (UEA lecturer, previously Hawaii),

     • Dr Simon Holgate (previously National Oceanography Centre),

     • Dr Laura Jackson (Hadley Centre, previously Princeton),

     • Dr Katarzyna Kenitz (Scripps, previously Copenhagen)

     • Dr Susan Leadbetter (UK Met Office, previously Duke),

     • Prof. Claire Mahaffey (Chair at Liverpool, previously Hawaii)

     • Dr Liping Ma

     • Dr Alison McLaren (previously UK Met Office)

     • Dr Ciara Pimm (postdoc at Liverpool)

     • Dr Jane O'Dwyer (previously Polar institute, Norway)

     • Dr Matthew Pennington  

     • Dr Sarah Reynolds (Lecturer at Portsmouth)

     • Dr Shaun Rigby (Hydrographic Office)

     • Dr Nick Rogan (previously postdoc at GEOMAR)

     • Dr Carl Spingys (National Oceanography Centre, Southampton)

     • Dr Kat Turner (postdoc at GFDL, Princeton)


Previous research associates  include:


     • Prof. Dr Guatliero Badin (fixed-term Lecturer at Hamburg, previously Princeton and Boston)

     • Dr Anna Hickman (NERC fellow and Lecturer at Southampton),

     • Dr Jonathan Lauderdale (Research scientist, MIT),

     • Dr Kevin Stratford

     • Dr Chris Wilson (National Oceanography Centre).


Previous fellows and visitors:


     •Dr Andrew Barton, a US NSF fellow working on phytoplankton community structure  (Scripps)



Collaborators, I work with a wide range of scientists

• Colleagues in Ocean Sciences at Liverpool University, including Vassil Roussenov, Claire Mahaffey, Jonathan Sharples, Alessandro Tagliabue and Chris Hughes;

• Researchers in the National Oceanography Laboratory , including Anna Katavouta, John Huthnance  and Phil Woodworth at Liverpool, and Pete Brown, Louis Clement and Darren Rayner at Southampton;

• Researchers within the UK, including at Southampton, Phil Goodwin and Alberto Naveira Garabato, at the Hadley Centre, Doug Smith and Chris Jones, Tim Woollings at Oxford University, at Imperial College, Paulo Ceppi, and at the British Antarctic Survey, Dr Andrew Meijers;

• Formers members of my research group, including Anna Katavouta (NOC Liverpool), Phil Goodwin (Associate professor, Southampton), and Jonathan Lauderdale (Research fellow, MIT);

•International colleagues at MIT, Professor Mick Follows on the modeling of the carbon cycle, at Georgia Tech, Professor Susan Lozier on ocean heat storage and overturning, and at Bern University, Professor Thomas Froelicher, on longterm climate responses to carbon emissions.