Academic Background

Senior Lecturer in Biogeochemistry, University of Bristol, UK (2008 to present)

Lecturer in Biogeochemistry, University of Bristol, UK (2000-08)

Postdoctoral Fellow, The University of Western Ontario, Canada (1997-2000)

Ph.D. Geology (1997), University of Western Ontario, Canada

B.Sc. Geological Engineering (1991), University of New Brunswick, Canada

1. Publications
   

2. Research Supervision
   

3. Teaching
   

4. Funding

Research Overview

My research is focused on the biogeochemistry of carbon cycling with specific emphasis on the exchange of methane (CH4) between natural environments and the atmosphere.  Freshwater peatlands have been my main area of interest for more than 15 years but externally funded projects also have included cold seeps in continental margin sediments, emissions from submarine mud volcanoes, deep-sea hydrothermal vents, uptake of atmospheric CH4 in mineral soils, methanogenesis in sub-glacial sediments and CH4 cycling in saline wetlands.  Stable isotopes figure prominently in all this work both at the natural abundance level and through the use of 13C and 2H-enriched compounds as tracers. Accurate characterization of isotope signatures of fluxes and the factors that influence their stability is essential for constraining mass balance budgets and for interpreting changes in the isotope composition of atmospheric gases both from modern-day monitoring networks and from palaeo-records derived from air bubbles trapped in ice cores.

New developments in passive radiation and laser spectroscopic techniques show promise for advancing the study of trace gas cycling. We are presently adapting a thermal infrared camera for visualization of CH4 emissions in real-time.  The technique should allow abrupt emissions events from peatlands and other sources to be monitored and correlated with external-forcing, such as changes in atmospheric pressure. The recent BIOGAS initiative with colleagues in the Bristol School of Geography has funded the purchase of four laser cavity ring down analyzers, including two iso-CH4 analyzers (delivery in June 2010) which are the first commercial laser analyzers capable of measuring 13C/12C ratios in CH4 at low ppmv levels.