Marine Optics

This programme is principally concerned with the optical oceanography of turbid coastal waters, including in situ and satellite remote sensing. Our objective is to develop a fundamental understanding of the optics of these waters and to apply this to
(i) the remote sensing of optically active constituents and hence
(ii) developing better models of the processes controlling water quality in shelf seas.

Current Research

The research programme in optical oceanography at Menai bridge is particularly concerned with the optics of turbid water. Highlights of this work include the development of methods for determining the surface concentration of suspended sediments from visible band satellite images, and the application of these measurements to improve our modelling of the physics of suspended sediments in shelf seas. This work continues, and recent advanced have included a successful explanation of isolated turbidity maxima, which appear to defy diffusion, and development of methods for estimating suspended sediment floc size from space.

A second theme here has been the optics of coloured dissolved organic matter (CDOM), and the exploration of the possibilities of remote sensing of salinity in estuaries, using CDOM as a proxy. Not all of this work has been confined to Europe: in 1998 a survey was conducted of the optics of the Zambezi river plume, and collaborations and field work have been and carried out with staff at the Virginia Institute of Marine Science, during which we developed and tested a theory of the interaction of the solar daily cycle and the tide. Much of this work is too recent to have been cited much, but one recent paper “Interpreting the colour of an estuary” was the third most downloaded paper from the journal’s science direct web site for 2004.

Associated publications

Kratzer,S., Buchan,S. and Bowers, D.G. (2003) Testing long term trends in turbidity in the Menai Strait, North Wales. Estuarine, Coastal and Shelf Science, 56, 221-226

C.E.Binding and D.G.Bowers (2003) Measuring the salinity of the Clyde Sea from remotely sensed ocean colour. Estuarine,Coastal and Shelf Science, 57, 605-611.

Binding,C.E., Bowers,D.G. and Mitchelson-Jacob, E.G. (2003) An algorithm for the retrieval of suspended sediment concentrations from SeaWiFS ocean colour satellite imagery International Journal of Remote Sensing, 24, 3791-3806

White, M., Bowers, D., S. Gaffney, and P. Bowyer (2003). Interannual variability in Irish Sea turbidity and relation to wind strength. Proceedings of the Royal Irish Academy, 103B, 83-90

D.G.Bowers (2003) A simple turbulent energy-based model of fine suspended sediments in the Irish Sea. Continental Shelf Research, 23, 1495-1505

D.G.Bowers, D.Evans, D.Thomas, K.Ellis and P.J.le B.Williams (2004). Interpreting the colour of an estuary. Estuarine, Coastal and Shelf Science, 59,13-20

D.G.Bowers and J.M.Brubaker (2004) Underwater sunlight maxima in the Menai Strait. Journal of Optics A: Pure and Applied Optics, 6, 684 689.

K.M.Ellis, D.G.Bowers and S.E.Jones (2004) A study of the temporal variability in particle size in a high energy regime. Estuarine, Coastal and Shelf Science, 61, 311-315.

C.E.Binding, D.G.Bowers and E.G.Mitchelson-Jacob (2005) Estimating suspended sediment concentrations from ocean colour measurements in moderately turbid waters; the impact of variable particle scattering properties. Remote Sensing of Environment, 94, 373-383

B.Hakansson and D.G.Bowers (2005) Baltic Sea remote sensing and bio-optical modelling – guest editor’s preface. International Journal of Remote Sensing, 26, 231

D.G.Bowers, K.M.Ellis and S.E.Jones (2005) Isolated turbidity maxima in Shelf Seas. Continental Shelf Research, 25, 1071-1080

Lisa Feighery, M. White, D. Bowers, G. O'Riain & P. Bowyer Using a digital camera for water quality and river plume measurements in the coastal zone. International Journal of Remote Sensing, in press

Rachel Brockway, David Bowers, Antonio Hoguane, Veronica Dove, Valentina Vassele A note on salt intrusion in funnel shaped estuaries: application to the Incomati Estuary: Mozambique. Estuarine, Coastal and Shelf Science. Accepted July 2005

D.G.Bowers and C.E.Binding Optical Properties of Mineral Suspended particles in the sea: a review and synthesis. Estuarine, Coastal and Shelf Science, accepted October 2005