MORSE: mesoscale ocean radar signature experiments

The MORSE project is devoted to furthering the understanding of the imaging of the ocean surface by synthetic aperture radar (SAR) in the presence of internal waves. The research is being undertaken by a Consortium of four University and two commercial partners under the MAST III initiative of the CEC, Brussels. Work on the 3-year project started on 1st February 1996. A tank experiment is undertaken using the European (Coriolis) facility at the Joseph Fourier University, Grenoble. The tank water surface will be imaged by a new W-band radar built by the Department of Electronic and Electrical Engineering, University College, London. The images will be compared and contrasted with SAR ocean imagery from satellites such as ERS-1 and 2 or Radarsat. There is still much uncertainty relating to how one might extract useful information from such SAR imagery of the ocean surface. Not least of the remaining problems is how the ocean surface is actually imaged at the various wavelengths used by the radars, and how that imaging process depends on polarisation, angle of incidence, height above the ocean, speed of motion of the viewing aperture with respect to the ocean surface etc. Of particular concern is understanding of the dependency of the imaging process on the radar wavelength at lengths in the one centimetre range. To this end, the W-band radar is to be built. Operating at a wavelength of 3 mm, it will probe the tank water surface at capillary wavelengths, a region in which very little, if any, SAR imagery is available and in which the capillary waves are known to be considerably steep. Comparison of a variety of images, radars, image formation mechanisms and image modelling results are to be made, especially in those situations which involve the straining of the tank and ocean surface by currents, with particular emphasis on currents induced by internal waves