Wu-Yang Tsai

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This paper presents a study to demonstrate the potential of a spaceborne u-band scatterometer to monitor global snow cover. Global u-band data were acquired by the National Aeronautics and Space Administration (NASA) Scatterometer (NSCAT) operated on the Advanced Earth Observing Satellite (ADEOS) from September 1996 to June 1997. NSCAT backscatter patterns(More)
The QuikSCAT radar measurements of several tropical cyclones in 1999 have been studied to develop the geophysical model function (GMF) of Ku-band radar 0s for extreme high wind conditions. To account for the effects of precipitation, we analyze the co-located rain rates from the Special Sensor Microwave/Imager (SSM/I) and propose the rain rate as a(More)
Scatterometer instruments are active microwave sensors that transmit a series of microwave pulses and measure the returned echo power to determine the normalized radar backscattering cross section (sigma-0) of the ocean surface from which the speed and direction of near-surface ocean winds are derived. The NASA Scatterometer (NSCAT) was launched on board(More)
Spaceborne wind scatterometers provide useful measurements of ocean surface winds and are important to climatological studies and operational weather forecasting. Past and currently planned scatterometers use measurements of the copolarized backscatter cross-section at different azimuth angles to infer ocean surface wind speed and direction. Although(More)
Conically scanning pencil-beam scatterometer systems, such as the recently launched SeaWinds radar, constitute an important class of instruments for spaceborne climate observation. In addition to ocean winds, scatterometer data are being applied to a wide range of land and cryospheric applications. A key issue for future scatterometer missions is improved(More)
The Ku-band dual-polarized backscatter signatures of ocean surfaces are described in this paper with the airborne scatterometer measurements collected in the Hurricane Ocean Wind Experiment in September 1997. The data collected from flights over Hurricane Erika provide a direct evidence that there are wind direction signals in the vertically and(More)
SeaWinds1 B is an spaceborne instrument, under design at the Jet Propulsion J.-aboriitory, to accurately measure the speed and direction of ocean surface winds at high resolutions. SeaWinds-l B consists of a scatterometer and a polarimetric wind radiometer. The scatterometer employs range compression to increase the resolution of its sigma-O measurements.(More)
Several spaceborne scatterometer missions have been successfully flown in the past decade. In addition to the primary mission of measuring ocean surface wind speed and direction, these measurements have proven useful in global scale climate studies of land and ice phenomena as well. A key shortcoming of the scatterometer in these measurements has been the(More)
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