My PhD and initial postdoctoral research were in astrophysics with an emphasis on the propagation of optical radiation and the emission of thermal radiation. When I came to Swansea in 2004, I developed a new approach to carbon modelling, simulating photosynthesis in tree canopies through the transfer of both diffuse and direct sunlight.

My current research and teaching interests focus on carbon, water and energy exchange between the land-surface and the atmosphere. I seek to understand fully these processes, particularly over vegetation, and how they might change under a future climate. I use both complex and simple Land-Surface Models to simulate these processes, calibrated and constrained by ground-based (eddy covariance FLUXNET) observations and satellite remote-sensing (e.g. MODIS).

Areas of expertise:

1. Environmental modelling and radiative transfer in vegetation canopies
2. Global simulations of carbon, water and energy exchange between the landsurface and the atmosphere
3. Parameter retrieval of biophysical properties using optimisation methods
4. Assimilation of eddy covariance and satellite remote sensing into simple and complex Land-Surface Models.

Publications

  1. Reconciling simulations of seasonal carbon flux and soil water with observations using tap roots and hydraulic redistribution: A multi-biome FLUXNET study. Agricultural and Forest Meteorology 198-199, 309-319.
  2. The sensitivity of models of gross primary productivity to meteorological and leaf area forcing: A comparison between a Penman–Monteith ecophysiological approach and the MODIS Light-Use Efficiency algorithm. Agricultural and Forest Meteorology 218-219, 11-24.
  3. Retrieval of seasonal Rubisco-limited photosynthetic capacity at global FLUXNET sites from hyperspectral satellite remote sensing: Impact on carbon modelling. Agricultural and Forest Meteorology 232, 74-88.
  4. From site-level to global simulation: Reconciling carbon, water and energy fluxes over different spatial scales using a process-based ecophysiological land-surface model. Agricultural and Forest Meteorology 176, 111-124.
  5. & Comparing the performance of different stomatal conductance models using modelled and measured plant carbon isotope ratios (δ13C): implications for assessing physiological forcing. Global Change Biology 19(6), 1709-1719.

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Teaching

  • GEG237 Global Vegetation Patterns and Dynamics

    In this module, we account for vegetation patterns on different spatial scales (global, regional and local), according to their environment and the requirements of plants for growth and survival. We examine how the distribution of vegetation has changed on different timescales and how it is likely to be altered in the future by human activities. We employ a series of case studies (e.g. water-limited and temperature-limited ecosystems) to reveal the impact of environment on vegetation and also how plants interact with their own environment through adaptation and sometimes through feedback mechanisms.

  • GEG264B Environmental Research Methods B

    The module builds upon student knowledge covers research project design, data collection and data analysis. Students are introduced to a range of laboratory and field techniques in physical geography along with statistical analyses and presentation skills. They gain experience in describing and interpreting results derived from laboratory techniques concerned with reconstructing the depositional history of sediments, chemical analysis of sediments from a variety of sources and the simulation of geomorphological processes. Students are also introduced to dissertation research. The module culminates in a poster presentation (including short oral introduction to poster) on one of the projects they have undertaken.

  • GEG268 Dissertation Preparation

    The module prepares students for their independent research dissertation through dissertation fairs, lectures and a series of tutorials focusing upon the formulation and construction of a research proposal. The module also includes three lectures which explore career opportunities for Geography graduates and skills to enhance graduate employability.

  • GEG354 Environmental Modelling

    Increasingly used to represent climatic, biogeochemical, and ecological systems, computer modelling is a vital tool to understand environmental change. This module provide a practical introduction to the various methods, techniques, and skills required for computerized environmental modelling. Exploring the broad arena of environmental modelling, the module demonstrates how to represent an environmental problem in conceptual terms, formalize the conceptual model using simple mathematical expressions, convert the mathematical model into a program that can be run on a desktop or laptop computer, and examine the results produced by the computational model. Equally important, the module imparts skills that allow you to develop, implement, and experiment with a range of computerized environmental models. The emphasis is on active engagement in the modelling process rather than on passive learning about a suite of well-established models. The module tries to take a practical approach throughout, one that does not get bogged down in the details of the underlying mathematics and that encourages learning through "hands on" experimentation.

  • GEGM10 Satellite Remote Sensing

    This module explains the use of remote sensing as a tool for gathering and analyzing information about human resources and the natural environment. It is appropriate for students who would find it valuable to understand how information about human activity and environmental change is retrieved from images of the Earth acquired by satelite or aircraft instruments. Emphasis is placed on the role of ongoing missions in providing operational information for science and society. Lecture material is supported by hands-on experience exploring satellite images in a computer environment.