The oceans play a hugely important role in the global carbon cycle and in energy transport mechanisms that influence world climate. Monitoring oceans is difficult due to the vast areas involved, the harsh environmental conditions and the rapid temporal variability of marine biogeochemical systems. Optical sensors can provide information about biological and mineral particles and dissolved substances. The technology is particularly suitable as optical sensors can be deployed on a variety of platforms, from satellites and aircraft to in situ moorings and underwater vehicles. David’s research is currently focused on improving the quality of products obtained from ocean colour remote sensing signals and in situ optical measurements of absorption, scattering and fluorescence. He is also interested in development of new platforms for optical instruments in oceanography such as micro-satellites for Earth observation and in situ profiling moorings. The research combines significant time spent at sea making measurements, numerical simulation of underwater and water leaving light fields and statistical data analysis. Most of the work is concentrated on optically complex shelf seas (e.g. Bristol Channel, Irish Sea, Mediterranean) where the influence of terrestrial and anthropogenic sources are strongest, though more recently he has started to develop interests in optical complexity in more open ocean areas that are subject to episodic inputs of wind-borne particulates. A key element of David’s NERC Fellowships has been the development of several very successful collaborations with partners in UK and international institutions.

David has recently undertaken consultancy work on a European Space Agency funded contract to establish baseline knowledge for the next generation of ESA ocean colour sensors. This work was sub-contracted through contacts with ARGANS, a very promising young consultancy business, and facilitated further development of links with colleagues at HZG in Germany.

David has also established strong links with WETLabs Inc. Research Division (Rhode Island, USA), a major developer and supplier of optical oceanographic instrumentation. This work includes development of improved scattering corrections for in situ absorption and attenuation sensors as well as development of a spectral deconvolution method for interpretation of optical signals.

Our group is interested in problems of radiance transfer in seawater, light utilisation by phytoplankton, optical monitoring of ecological processes, and remote sensing in the marine environment. These problems all involve the application of physical principles in an interdisciplinary context. Activities range from in situ measurement of optical properties at sea from ships and other platforms, through radiative transfer simulations of underwater and water leaving light fields, to development of new algorithms for interpretation of ocean colour remote sensing data from satellite-borne sensors.