Paul is interested in the role played by ocean biology and chemistry in the climate system.
Areas of expertise:
Paul works with the Met Office Hadley Centre's carbon-cycle and Earth System models (HadCM3 and HadGEM2-ES). Using these models he can explore how the ocean's biology and chemistry can influence the climate system and how changes in the climate system can stimulate changes in marine biology and chemistry. Recently a lot of Paul's work has been focused on getting our new state of the art Earth System Model, HadGEM2-ES, ready to undertake the IPCC's 5th assessment climate simulations.
Models of the kind Paul works with can be used to investigation interactions within the Earth System. Paul is particularly interested in how changing ocean pH,in response to marine anthropogenic CO2 uptake, will affect ocean carbon uptake through its influence of calcium carbonate formation and dissolution. Paul's ocean acidification modelling work builds on experimental studies undertaken during his PhD, and involves ongoing national and international collaborations. Paul's broader scientific interest range from understanding the role that sinking organic carbon may have on changes in the air-sea flux of CO2, to understanding the importance of biologically produced gasses (for example dimethylsulphide) within the climate system.
Paul received his undergraduate and doctorate degrees from the Department of Earth Sciences in Oxford University, before joining the Met Office Hadley Centre in August 2008.
In Oxford Paul was working in the field of palaeoclimate, trying to develop and apply new and improved geochemical climate-proxy techniques based on phytoplankton shell chemistry. Paul's work in Oxford ranged from understanding past ENSO (Rickaby and Halloran, 2005), through automated sediment processing techniques (Halloran, Rust and Rickaby, 2009) to examining the impact of ocean acidification on marine phytoplankton (Iglesias-Rodriguez and Halloran et al., 2008 and Halloran et al., 2008).