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	Provedor de dados ArchiMer (3) Autor Li, Xiaofeng (3) Chapron, Bertrand (2) Mouche, Alexis (2) Cheng, Yongcun (1) Kim, Tae-sung (1) Lee, Moonjin (1) Lu, Yiru (1) Park, Kyung-ae (1) Perrie, William (1) Tournadre, Jean (1) Wang, He (1) Xu, Qing (1) Zhang, Biao (1) Mais... Palavra-chave Altimeter (1) Coastal wind speed (1) Full-polarization synthetic aperture radar (SAR) (1) Geophysical model function (GMF) (1) Oil spill (1) Sea surface temperature (SST) front (1) Sea surface wind field (1) Sigma0 bloom (1) Stability-effect (1) Synthetic aperture radar (SAR) (1) Waveform (1) Wind direction (1) Mais... Tipo do documento Text (3) Ano 2018 (1) 2017 (2) País France (3) Idioma Inglês (3)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 3 Primeira ... 1 ... Última Impacts of oil spills on altimeter waveforms and radar backscatter cross-section ArchiMer Cheng, Yongcun; Tournadre, Jean; Li, Xiaofeng; Xu, Qing; Chapron, Bertrand. Ocean surface films can damp short capillary-gravity waves, reduce the surface mean square slope, and induce “sigma0 blooms” in satellite altimeter data. No study has ascertained the effect of such film on altimeter measurements due to lack of film data. The availability of Environmental Response Management Application (ERMA) oil cover, daily oil spill extent and thickness data acquired during the Deepwater Horizon (DWH) oil spill accident provides a unique opportunity to evaluate the impact of surface film on altimeter data. In this study, the Jason-1/2 passes nearest to the DWH platform are analyzed to understand the waveform distortion caused by the spill as well as the variation of σ0 as a function of oil thickness, wind speed and radar band. Jason-1/2... Tipo: Text Palavras-chave: Oil spill; Altimeter; Sigma0 bloom; Waveform. Ano: 2017 URL: http://archimer.ifremer.fr/doc/00381/49203/49635.pdf Observation of Wind Direction Change on the Sea Surface Temperature Front Using High-Resolution Full Polarimetric SAR Data ArchiMer Kim, Tae-sung; Park, Kyung-ae; Li, Xiaofeng; Mouche, Alexis; Chapron, Bertrand; Lee, Moonjin. In this study, we derive high-resolution wind speeds and directions from full-polarization synthetic aperture radar (SAR) data. Previous wind retrieval result from conventional single-polarization SAR data has a limitation to resolve small-scale structures in the surface wind because external wind direction data with coarser spatial resolution than those of SARs have been commonly used as an input. Using fully polarimetric SAR data, however, both wind speed and direction can be derived with high resolution from the image itself without any ancillary data. We derive wind field off the southern coast of Korea from the Radarsat-2 quad-polarization data and investigate the spatial variation. The retrieved wind field from the Radarsat-2 image presents a... Tipo: Text Palavras-chave: Full-polarization synthetic aperture radar (SAR); Sea surface temperature (SST) front; Sea surface wind field; Stability-effect; Wind direction. Ano: 2017 URL: http://archimer.ifremer.fr/doc/00374/48485/48786.pdf A C-Band Geophysical Model Function for Determining Coastal Wind Speed Using Synthetic Aperture Radar ArchiMer Lu, Yiru; Zhang, Biao; Perrie, William; Mouche, Alexis; Li, Xiaofeng; Wang, He. A new geophysical model function (GMF), called C_SARMOD2, has been developed to relate high-resolution C-band normalized radar cross section (NRCS), acquired in VV polarization over the ocean, to the 10-m height wind speed. A total of 3078 RADARSAT-2 and Sentinel-1A VV-polarized synthetic aperture radar (SAR) images, acquired under different wind speed conditions, were collocated with in situ buoy measurements. The paired dataset was used to derive transfer functions and coefficients of C_SARMOD2, and then to validate the wind speed retrievals. The comparison between SAR-retrieved wind speeds and buoy measurements show almost no bias and a root mean square error of 1.84 m/s. Two representative quad-and dual-polarization SAR images, acquired from coastal... Tipo: Text Palavras-chave: Coastal wind speed; Geophysical model function (GMF); Synthetic aperture radar (SAR). Ano: 2018 URL: https://archimer.ifremer.fr/doc/00452/56390/60555.pdf Registros recuperados: 3 Primeira ... 1 ... Última

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