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The spectral backscattering properties of marine particles /Whitmire, Amanda L. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 128-136). Also available on the World Wide Web.
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Underwater machine vision : recovering orientation and motion of Lambertian planar surfaces in light attenuating mediaYu, Zhihe January 1990 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1990. / Includes bibliographical references (leaves 124-130) / Microfiche. / x, 130 leaves, bound ill. 29 cm
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Optical absorption of pure water and sea water using the integrating cavity absorption meterPope, Robin Merl, January 1993 (has links)
Thesis (Ph. D.)--Texas A & M University, 1993. / Vita. Includes bibliographical references (p. 204-208).
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Computational Intelligence Approaches to Ocean Color InversionSlade, Jr., Wayne Homer January 2004 (has links) (PDF)
No description available.
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A Method to Quantify the Uncertainties Associated with Semi-Analytic Algorithm for Inversion of Ocean ColorWang, Peng January 2004 (has links) (PDF)
No description available.
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Ocean color atmospheric correction based on black pixel assumption over turbid watersLiu, Huizeng 11 April 2019 (has links)
Accurate retrieval of water-leaving reflectance from satellite-sensed signal is decisive for ocean color applications, because water-leaving radiance only account for less than 10% of satellite-sensed radiance. The standard atmospheric correction algorithm relies on black pixel assumption, which assumes negligible water-radiance reflectance at the near-infrared (NIR) bands. The standard NIR-based algorithm generally works well for waters where the NIR water-leaving radiance is negligible or can be properly accounted for. However, the black pixel assumption does not hold over turbid waters, which results in biased retrievals of remote sensing reflectance (Rrs). Therefore, this study aimed to improve atmospheric correction over turbid waters. Based on Sentinel-3, two ways to cope with nonzero NIR water-leaving reflectance were explored. First, this study proposed to use artificial neural networks to estimate and correct NIR water-leaving reflectance at TOA (ANN-NIR algorithm). The rationale of it is that hydrosol optical properties are much simpler at NIR spectral region, where pure water absorptions are the dominant factor. The proposed algorithm outperformed the standard NIR-based algorithm over highly turbid waters. Considering results demonstrated in this study, ANN-NIR algorithm should be useful for ocean color sensors with less than two SWIR bands. Second, this study adapted the SWIR-based algorithm for atmospheric correction of Sentinel-3 OLCI by coupling with the two SWIR bands of SLSTR. Three SWIR band combinations were tested: 1020 and 1613, 1020 and 2256, and 1613 and 2256 nm. The SWIR-based algorithm obviously performed better than NIR-based algorithm over highly turbid waters, while the NIR-based is still preferred for clear to moderately turbid waters. The SWIR band of 1020 nm combined with either SWIR band of 1613 or 2256 nm is recommended for the SWIR-based algorithm except for extremely turbid waters, because the band of 1020 nm has better radiometric performance. Over extremely turbid waters, the band combination of 1613 and 2256 nm should be used, since the water-leaving reflectance is still non-negligible at the band of 1020 nm over these waters. Considering atmospheric correction performance obtained by the NIR- and SWIR-based algorithms, the NIR-based and SWIR-based algorithm are practically applied over clear and turbid waters, respectively. This study revisited the effectiveness of the turbidity index for the current NIR-SWIR switching scheme. The turbidity index calculated from aerosol reflectance varies from 0.7 to 2.2, which is not close to one as expected. In addition to water-leaving reflectance, its value also depends on the spectral shape of aerosol reflectance, which varies with aerosol size distributions, aerosol optical thickness, relative humidity and observing geometries. To address this problem, this study proposed a framework to determine switching threshold for the NIR-SWIR algorithm. An Rrs threshold was determined for each MODIS land band centered at 469, 555, 645 and 859 nm, respectively. Their thresholds are 0.009, 0.016, 0.009 and 0.0006 sr-1, respectively. However, Rrs(469) tends to select SWIR-based algorithm wrongly for clear waters, while NIR-SWIR switching based on Rrs(859) tends to produce patchy patterns. By contrast, NIR-SWIR switching based on Rrs(555) with a threshold of 0.016 sr-1 and Rrs(645) with a threshold of 0.009 sr-1 produced reasonable results. Considering the contrasted estuarine and coastal waters, combined applications of NIR- and SWIR-based algorithm with the switching scheme should be useful for these waters. This study will contribute to better ocean color atmospheric corrections over turbid waters. Atmospheric correction algorithms based on black pixel assumption have been implemented and tested in this study, while combined applications of NIR-based and SWIR-based algorithms are recommended over contrasted transitional waters. However, further studies would still be required to further improve and validate atmospheric correction algorithms over turbid waters.
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Angular spectrum measurements of an underwater optical communication channel.Ross, Warren Steven January 1977 (has links)
Thesis. 1977. M.S.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / M.S.
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Modeling and application of multispectral oceanic sun glint observationsLuderer, Gunnar 02 October 2003 (has links)
The atmospheric radiative transfer model MOCARAT was developed and is
presented in this thesis. MOCARAT employs a Monte Carlo Technique for the
accurate modeling of band radiances and reflectances in an atmospheric system
with a ruffled ocean surface as a lower boundary. The atmospheric radiative
transfer is modeled with consideration of molecular Rayleigh scattering, Mie
Scattering and absorption on particulate matter, as well as band absorption by
molecules in the wavelength channels of interest. The bidirectional reflection
of downwelling light at the ocean surface is computed using the empirical relationship
between surface wind field and the slope distribution of wave facets
derived by Cox and Munk (1954a).
A method is proposed to use the oceanic sun glint for remote sensing applications.
The sensitivity of channel correlations to aerosol burden and type as well
as other atmospheric and observational parameters is assessed. Comparisons
of observed correlations with model results are used to check the consistency
of the calibration of the airborne Multichannel Cloud Radiometer (MCR) that
was employed during the Indian Ocean Experiment (INDOEX). The MCR calibration
exhibited large variability from flight to flight. The method was applied
to MODIS observations. Unlike the MCR, MODIS was stable where expected,
although numerical values for some of the wavelengths appear to depart from
theory. / Graduation date: 2004
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A QUANTITATIVE STUDY OF THE RADIANCE DISTRIBUTION AND ITS VARIATION IN OCEAN SURFACE WATERSWei, Jianwei 21 February 2013 (has links)
The radiance distribution provides complete information regarding the geometrical
structure of the ambient light field within the ocean. A quantitative study of the radiance
field in the dynamic ocean water is presented in this thesis work. The study starts with the development of a novel radiance camera for the measurement of the full spherical
radiance distribution at the ocean surface and depth. Nonlinear response functions are
designed and advanced radiometric calibrations are developed. The resulting camera
measures the radiance distribution in absolute units over an extremely high dynamic
range at fast rates. With the newly obtained radiance data, I have examined the fine
structure of both the downwelling and upwelling radiance distribution and its variation
with depth in optically diverse water types. The fully specified radiance distribution data
are used to derive all apparent optical properties and some inherent optical properties
including the absorption coefficient. With the camera fixed at shallow depths, I have
observed and determined the sea surface wave disturbance of the radiance distribution. It is found that the radiance fluctuates anisotropically with regard to its amplitude and
periodicity. Typical spatial structures of the dynamic radiance field are identified and
shown relevant to the surface waves and the solar zenith angles. The variability in the
radiance field also propagates to the irradiance field; the variability is pronounced in
measured irradiance depth profiles in the upper layers of the ocean. The statistics of the
irradiance fluctuations along the water depth, including the dominant frequency and
coefficient of variation, are derived using wavelet techniques and fitted to novel analytic
models. The results from the irradiance depth-profile decomposition are in agreement
with theoretical models and other independent measurements. This thesis work represents the first attempt to quantify the full light field and its variability in dynamic ocean waters and is of significant relevance to many other optics-related applications.
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Spatial structures of optical parameters in the California Current as measured with the Nimbus-7 Coastal Zone Color ScannerMcMurtrie, John T. January 1984 (has links)
Thesis (M.S.)--Naval Postgraduate School, 1984. / "March 1984." "N0001484 WR24001"--P. 1. Includes bibliographical references (leaves 144-148).
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