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Multiparameter radar analysis using wavelets

Posted on:1999-02-22Degree:Ph.DType:Dissertation
University:Colorado State UniversityCandidate:Tawfik, Ben Bella SayedFull Text:PDF
GTID:1468390014468454Subject:Engineering
Abstract/Summary:
Multiparameter radars have been used in the interpretation of many meteorological phenomena. Rainfall estimates can be obtained from multiparameter radar measurements. Studying and analyzing spatial variability of different rainfall algorithms, namely R(ZH), the algorithm based on reflectivity, R(ZH, ZDR), the algorithm based on reflectivity and differential reflectivity, R(KDP), the algorithm based on specific differential phase, and R(KDP, Z DR), the algorithm based on specific differential phase and differential reflectivity, are important for radar applications. The data used in this research were collected using CSU-CHILL, CP-2, and S-POL radars. In this research multiple objectives are addressed using wavelet analysis namely, (1) space time variability of various rainfall algorithms, (2) separation of convective and stratiform storms based on reflectivity measurements, (3) and detection of features such as bright bands.;The bright band is a multiscale edge detection problem. In this research, the technique of multiscale edge detection is applied on the radar data collected using CP-2 radar on August 23, 1991 to detect the melting layer.;In the analysis of space/time variability of rainfall algorithms, wavelet variance introduces an idea about the statistics of the radar field. In addition, multiresolution analysis of different rainfall estimates based on four algorithms, namely R(ZH), R( ZH, ZDR), R(K DP), and R(KDP, Z DR), are analyzed. The flood data of July 29, 1997 collected by CSU-CHILL radar were used for this analysis. Another set of S-POL radar data collected on May 2, 1997 at Wichita, Kansas were used as well. At each level of approximation, the detail and the approximation components are analyzed. Based on this analysis, the rainfall algorithms can be judged. From this analysis, an important result was obtained. The Z-R algorithms that are widely used do not show the full spatial variability of rainfall. In addition another intuitively obvious result was observed namely, R( KDP) has reduced the spatial variability due to smoothing of KDP estimates.;The convective and stratiform separation was studied using multiresolution analysis. The June 22, 1995 data collected by CSU-CHILL radar were used to evaluate the technique. Another set of data collected on August 23, 1991 representing stratiform conditions were also studied.
Keywords/Search Tags:Radar, Used, Data collected, Using, Rainfall, KDP
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