OSD Ocean Science Discussions OSD Ocean Sci. Discuss. 1812-0822 Göttingen, Germany 10.5194/osd-9-2851-2012 Measurement of turbulence in the oceanic mixed layer using Synthetic Aperture Radar (SAR) George S. G. 1 Tatnall A. R. L. 1 Astronautics Research Group, Faculty of Engineering & the Environment, University of Southampton, Southampton, UK 13 09 2012 9 5 2851 2883 Copyright: © 2012 S. G. George 2012 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://os.copernicus.org/preprints/9/2851/2012/osd-9-2851-2012.html The full text article is available as a PDF file from https://os.copernicus.org/preprints/9/2851/2012/osd-9-2851-2012.pdf

Turbulence in the surface layer of the ocean contributes to the transfer of heat, gas and momentum across the air-sea boundary. As such, study of turbulence in the ocean surface layer is becoming increasingly important for understanding its effects on climate change. Direct Numerical Simulation (DNS) techniques were implemented to examine the interaction of small-scale wake turbulence in the upper ocean layer with incident electromagnetic radar waves. Hydrodynamic-electromagnetic wave interaction models were invoked to demonstrate the ability of Synthetic Aperture Radar (SAR) to observe and characterise surface turbulent wake flows. A range of simulated radar images are presented for a turbulent surface current field behind a moving surface vessel, and compared with the surface flow fields to investigate the impact of turbulent currents on simulated radar backscatter. This has yielded insights into the feasibility of resolving small-scale turbulence with remote-sensing radar and highlights the potential for extracting details of the flow structure and characteristics of turbulence using SAR.

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