NERC PhD studentship: Fire, Atmospheric Oxygen and Ocean Anoxia

Supervisors: Dr Claire M. Belcher [Email Address Removed]
Prof. Timothy M. Lenton [Email Address Removed]
Prof. Stephen P. Hesselbo [Email Address Removed] (external

We are inviting applications for this NERC funded PhD studentship to commence September 2013. For eligible students the award will cover UK/EU tuition fees and an annual stipend (in 2013/14 this will be £13,726 for full-time students, pro rata for part-time students) for at least three years. This project is one of a number that are in competition for funding. Studentships will be awarded on the basis of merit.

Successful applicants will be based within Geography (Streatham Campus, Exeter) at the College of Life and Environmental Sciences, University of Exeter.

Project description

The Mesozoic (250-64 million years ago) saw several intervals that were subject to severe environmental changes. During these intervals the oceans experienced very high sea-surface temperatures and very low oxygen contents in marine water. These Oceanic Anoxic Events (OAEs) caused major chemical changes to the ocean and severely disrupted Earth’s carbon cycle. Carbon dioxide and oxygen levels in Earth’s atmosphere are controlled by biogeochemical feedbacks that take place on million year timescales. The major disruptions to Earth’s carbon cycle caused by these OAEs are believed to have interfered with the oxygen content of the atmosphere. Forest fires require oxygen in order to burn meaning that forest fire activity is highly sensitive to variations in the abundance of oxygen in our atmosphere. Therefore one way to test how significant changes in atmospheric oxygen were in response to OAEs is to combine analyses of the record of ancient fire preserved in rocks, in the form of fossil charcoal, with biogeochemical models of the Earth system across OAEs.

The successful student will study the record of fire activity preserved as a record of fossil charcoals across several OAE sections from across the globe. This will be used to assess any major changes in atmospheric oxygen across the OAE that may enhance or suppress fire activity. The student will then construct a biogeochemical model to create estimates of changes in carbon burial and fluxes of atmospheric carbon dioxide and oxygen in response to the switch to an anoxic ocean.

The student will be part of the expanding world leading Earth System Science group at The University of Exeter http://lifesciences.exeter.ac.uk/research/essg/. The group has diverse interests stretching from ancient evolutionary events through to predicting modern climate dynamics. The group is cross disciplinary and comprises members from the departments of Geography, Biosciences and Mathematics at the University of Exeter. The student will further have the opportunity to work with external collaborators as part of the project including Prof. Stephen Hesselbo at the University of Oxford.

You must have obtained, or be about to obtain, a First or Upper Second Class UK Honours degree, or the equivalent qualifications gained outside the UK, in Earth Science, Geology, Environmental Science, Maths or Physics. We seek candidates with an enthusiasm and ability to use and develop models as well as analyse data in the laboratory.