23 research outputs found
Improved Wind and Rain Estimation Over the Ocean Using QuikSCAT
The QuikSCAT scatterometer has proved to be a valuable tool in measuring the near-surface wind vector over the ocean. In raining conditions the instrument effectiveness is diminished by rain contamination of the radar return. To compensate for rain effects, two alternative estimation techniques have been proposed, simultaneous wind-rain retrieval and rainonly retrieval, which are appropriate under certain conditions. This paper proposes and outlines a Bayes estimator selection technique whereby a best estimate is selected from the simultaneous wind-rain, the rain-only and the conventional wind-only estimates. In this paper the Bayes estimator selection technique is introduced with a quick overview of the application to QuikSCAT wind and rain estimation. Results are demonstrated at both conventional and high resolutions for a case study which indicate that wind and rain estimates after Bayes estimator selection are more consistent with measured rain and have reduced noise levels over those produced by any of the individual estimators
Operational Use and Impact of Satellite Remotely Sensed Ocean Surface Vector Winds in the Marine Warning and Forecasting Environment
Rhodesia, Corn MillColorVolume 81, Page
Challenges to Satellite Sensors of Ocean Winds: Addressing Precipitation Effects
Measurements of global ocean surface winds made by orbiting satellite radars have provided valuable information to the oceanographic and meteorological communities since the launch of the Seasat in 1978, by the National Aeronautics and Space Administration (NASA). When Quick Scatterometer (QuikSCAT) was launched in 1999, it ushered in a new era of dual-polarized, pencil-beam, higher-resolution scatterometers for measuring the global ocean surface winds from space. A constant limitation on the full utilization of scatterometer-derived winds is the presence of isolated rain events, which affect about 7% of the observations. The vector wind sensors, the Ku-band scatterometers [NASA\u27s SeaWinds on the QuikSCAT and Midori-II platforms and Indian Space Research Organisation\u27s (ISRO\u27s) Ocean Satellite (Oceansat)-2], and the current C-band scatterometer [Advanced Wind Scatterometer (ASCAT), on the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT)\u27s Meteorological Operation (MetOp) platform] all experience rain interference, but with different characteristics. Over this past decade, broad-based research studies have sought to better understand the physics of the rain interference problem, to search for methods to bypass the problem (using rain detection, flagging, and avoidance of affected areas), and to develop techniques to improve the quality of the derived wind vectors that are adversely affected by rain. This paper reviews the state of the art in rain flagging and rain correction and describes many of these approaches, methodologies, and summarizes the results
Laboratory for Atmospheres 2007 Technical Highlights
The 2007 Technical Highlights describes the efforts of all members of the Laboratory for Atmospheres. Their dedication to advancing Earth Science through conducting research, developing and running models, designing instruments, managing projects, running field campaigns, and numerous other activities, is highlighted in this report
Laboratory for Atmospheres: 2006 Technical Highlights
The 2006 Technical Highlights describes the efforts of all members of the Laboratory for Atmospheres. Their dedication to advancing Earth science through conducting research, developing and running models, designing instruments, managing projects, running field campaigns, and numerous other activities, are highlighted in this report
 Ocean Remote Sensing with Synthetic Aperture Radar
The ocean covers approximately 71% of the Earth’s surface, 90% of the biosphere and contains 97% of Earth’s water. The Synthetic Aperture Radar (SAR) can image the ocean surface in all weather conditions and day or night. SAR remote sensing on ocean and coastal monitoring has become a research hotspot in geoscience and remote sensing. This book—Progress in SAR Oceanography—provides an update of the current state of the science on ocean remote sensing with SAR. Overall, the book presents a variety of marine applications, such as, oceanic surface and internal waves, wind, bathymetry, oil spill, coastline and intertidal zone classification, ship and other man-made objects’ detection, as well as remotely sensed data assimilation. The book is aimed at a wide audience, ranging from graduate students, university teachers and working scientists to policy makers and managers. Efforts have been made to highlight general principles as well as the state-of-the-art technologies in the field of SAR Oceanography