论文信息 - Shallow water bottom topography from radar imagery

Shallow water bottom topography from radar imagery

Radar imagery of shallow coastal waters (usually <40 m deep) contain unexplained features1–3 resembling the bottom topography. Since microwave radiation does not penetrate far in sea-water, these features must be the result of hydrodynamic processes coupled to the bottom topography that modulate the amplitude of the short (Bragg resonant) sea-surface waves, the main contributors to the backscattered radar power4,5. Because many different hydrodynamic processes operate in coastal waters, and the precise mechanism which generates the radar images is not fully established, a programme to explore the mechanism(s) was initiated at the US Naval Research Laboratory. Here we give a brief description of the possible mechanisms and results from the pilot experiment conducted in July 1982, 40 nautical miles south-east of Nantucket Island.

[1] Duncan B. Ross,et al. Ocean surface patterns above sea-floor bedforms as recorded by radar, Southern Bight of North Sea , 1981 .

[2] D. Ross,et al. On the detectability of ocean surface waves by real and synthetic aperture radar , 1981 .

[3] Robert C. Beal,et al. Spaceborne synthetic aperture radar for oceanography , 1981 .

[4] M. Longuet-Higgins,et al. The changes in amplitude of short gravity waves on steady non-uniform currents , 1961, Journal of Fluid Mechanics.

[5] J. Wright,et al. Detection of ocean waves by microwave radar; The modulation of short gravity-capillary waves , 1978 .

[6] G. Komen,et al. The generation of residual vorticity by the combined action of wind and bottom topography in a shallow sea , 1981 .

[7] P. Hoogeboom,et al. Microwave Measurements Over the North Sea , 1978 .

[8] G. Valenzuela,et al. An asymptotic formulation for SAR images of the dynamical ocean surface , 1980 .

[9] J. Zimmerman,et al. Topographic generation of residual circulation by oscillatory (tidal) currents , 1978 .

[10] I. S. Robinson,et al. Tidal vorticity and residual circulation , 1981 .

[11] G. Komen,et al. Residual vorticity induced by the action of tidal currents in combination with bottom topography in the Southern Bight of the North Sea , 1981 .