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The off-specular peak and polarisation effects of an undulating underwater suface

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dc.contributor.authorClavano, Wilhelmina R.
dc.contributor.authorPhilpot, William D.
dc.date.accessioned2006-03-03T18:45:20Z
dc.date.available2006-03-03T18:45:20Z
dc.date.issued2006-03-03T18:45:20Z
dc.descriptionhttp://www.hydrooptics.spb.ru/onw2005/index.phpen_US
dc.description.abstractPeriodic undulations are used to describe underwater bottom roughness. An expression of the bi-directional reflectance distribution function (BRDF) is given that is dependent on the given roughness metric. Highlights include an off-specular peak and polarisation effects. For an undulating underwater surface, we have shown through geometric optics that reflectance from a rough diffuse surface increases as the viewing direction approaches the backward direction even in the absence of shadowing and/or self-shading (Clavano & Philpot (2003), see also Cox & Munk (1956)). The effects of shadowing and self-shading are equivalent to applying a geometrical attenuation factor to specular reflectance, which is similar to an analysis of morphological effects using triangular waves by Zaneveld & Boss (2003). We show that a reflectance peak displaced away from the specular direction occurs at large angles of incidence (relative to the global normal) as the surface gets rougher (part of work in Clavano & Philpot (2004)). Similar results have been shown for oil films on ocean surfaces using Monte Carlo methods by Otremba & Piskozub (2004) and Otremba (2004). As a general result, an expression of the full bi-directional reflectance distribution function (BRDF) is given. While geometrical effects play a significant role in the reflectance distribution, we consider polarisation effects (as in Mullamaa (1962, 1964)) to gain more insight into real-world reflectances and compare with empirical distributions described by Cox & Munk (1956).en_US
dc.description.sponsorshipCornell University Graduate Schoolen_US
dc.format.extent142441 bytes
dc.format.extent68992 bytes
dc.format.mimetypeapplication/pdf
dc.format.mimetypeapplication/pdf
dc.identifier.urihttps://hdl.handle.net/1813/2666
dc.language.isoen
dc.relation.ispartofseriesOptics of Natural Waters;Third International Conference
dc.relation.ispartofseries;St. Petersburg, Russia
dc.subjectBRDFen_US
dc.subjectroughnessen_US
dc.subjectpolarisationen_US
dc.subjectoff-specularen_US
dc.subjectunderwateren_US
dc.subjectgeometric opticsen_US
dc.subjectreflectanceen_US
dc.subjectshadowingen_US
dc.subjectbi-directional reflectance distribution functionen_US
dc.titleThe off-specular peak and polarisation effects of an undulating underwater sufaceen_US
dc.typepresentationen_US

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