OSD Ocean Science Discussions OSD Ocean Sci. Discuss. 1812-0822 Göttingen, Germany 10.5194/osd-9-2885-2012 Fine-scale features on the sea surface in SAR satellite imagery – Part 1: Simultaneous in-situ measurements Soloviev A. 1 Maingot C. 1 Matt S. 1 Dodge R. E. 1 Lehner S. 2 Velotto D. 2 Brusch S. 2 Perrie W. 3 Hochberg E. 4 Nova Southeastern University's Oceanographic Center, Dania Beach, USA German Aerospace Center, Wessling, Germany Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada Bermuda Institute of Ocean Sciences, St. George's, Bermuda 17 09 2012 9 5 2885 2914 Copyright: © 2012 A. Soloviev et al. 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/9/2885/2012/osd-9-2885-2012.html The full text article is available as a PDF file from https://os.copernicus.org/preprints/9/2885/2012/osd-9-2885-2012.pdf

This work is aimed at identifying the origin of fine-scale features on the sea surface in synthetic aperture radar (SAR) imagery with the help of in-situ measurements as well as numerical models (presented in a companion paper). We are interested in natural and artificial features starting from the horizontal scale of the upper ocean mixed layer, around 30–50 m. These features are often associated with three-dimensional upper ocean dynamics. We have conducted a number of studies involving in-situ observations in the Straits of Florida during SAR satellite overpass. The data include examples of sharp frontal interfaces, wakes of surface ships, internal wave signatures, as well as slicks of artificial and natural origin. Atmospheric processes, such as squall lines and rain cells, produced prominent signatures on the sea surface. This data has allowed us to test an approach for distinguishing between natural and artificial features and atmospheric influences in SAR images that is based on a co-polarized phase difference filter.

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