Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 10 of 10 for “"wind retrieval"”.
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High Resolution Wind Retrieval for SeaWinds on QuikSCAT
… developed that enables improved the resolution wind estimates from SeaWinds data. This thesis presents the development of three key portions of the high resolution wind retrieval algorithm: Compositing individual σ-0 measurements and Kp, Retrieved wind bias correction, and ambiguity selection …
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Hurricane Wind Retrieval Algorithm Development For An Airborne Conical Scanning Scatterometer
Reliable ocean wind vector measurements can be obtained using active microwave remote sensing (scatterometry) techniques. With the increase in the number of severe hurricanes making landfall in the United States, there is increased emphasis on operational monitoring of hurricane winds from …
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An Implementation of Field-Wise Wind Retrieval for Seawinds on QuikSCAT
<p>Field-wise wind estimation (also known as model-based wind estimation) is a sophisticated technique to derive wind estimates from radar backscatter measurements. In contrast to the more traditional method known as point-wise wind retrieval, field-wise techniques estimate wind field model …
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A Field-Wise Retrieval Algorithm for SeaWinds
… of 1999 NASA will launch the scatterometer SeaWinds, beginning a 3 year mission to measure the ocean winds. SeaWinds is different from previous spaceborne scatterometers in that it employs a rotating pencil-beam antenna as opposed to fixed fan-beam antennas. The scanning beam provides greater …
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Uncertainties in Oceanic Microwave Remote Sensing: The Radar Footprint, the Wind-Backscatter Relationship, and the Measurement Probability Density Function
… parameters such as the near-surface vector wind. To obtain accurate estimates, a precise understanding of the measurements is critical. This work clarifies and quantifies specific uncertainties in the scattered power measured by an active radar instrument.</p> <p>While there are many sources …
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An Analysis of SeaWinds Simultaneous Wind/Rain Retrieval in Severe Weather Events
Scatterometers, such as SeaWinds, can provide wide coverage of ocean surface winds. They estimate near-surface wind vectors by relating measured radar backscatter to a geophysical model function. However, SeaWinds measurements are also sensitive to rain, and conventional wind retrieval degrades in …
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Azimuth Modulation of the Radar Backscatter at Near-Normal Incidence
… increasingly important. Common applications are wind retrieval and global weather forecasting and characterization. Because of the common use of ocean radar measurements, it is important to understand the sensitivity of the backscatter to both radar parameters and surface parameters.</p> <p>At …
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Satellite Scatterometers: Calibration Using a Ground Station and Statistical Measurement Theory
… methodology is established for calibration of SeaWinds, NASA's current scatterometer, using a receive-only ground station. Principles of the methodology are implemented, new analysis techniques developed, and important results obtained for instrument timing, frequency, power, position, and …
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Validation, trend analysis & bias reduction through satellite fusion of the cloud-top height record from terra MODIS & MISR
… precise climate records of global cloud property retrievals from satellite sensors that maintain long-term orbital stability. While recent space-based active sensor records have improved our understanding of vertical cloud distributions, satellite passive sensors are better suited for detecting …
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Wind Scatterometry with Improved Ambiguity Selection and Rain Modeling
Although generally accurate, the quality of SeaWinds on QuikSCAT scatterometer ocean vector winds is compromised by certain natural phenomena and retrieval algorithm limitations. This dissertation addresses three main contributers to scatterometer estimate error: poor ambiguity selection, estimate …