Ka-밴드 구름레이더 자료품질 및 구름통계 기초연구
Preliminary Analysis of Data Quality and Cloud Statistics from Ka-Band Cloud Radar
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조회
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다운로드
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참고문헌
키워드
초록
The Ka-band cloud radar (KCR) has been operated by the National Institute ofMeteorological Research (NIMR) of Korea Meteorological Administration (KMA) at BoseongNational Center for Intensive Observation of severe weather since 2013. Evaluation of dataquality is an essential process to further analyze cloud information. In this study, we estimatethe measurement error and the sampling uncertainty to evaluate data quality. By using verticallypointing data, the statistical uncertainty is obtained by calculating the standard deviationof each radar parameter. The statistical uncertainties decrease as functions of sampling number. The statistical uncertainties of horizontal and vertical reflectivities are identical (0.28 dB). On the other hand, the statistical uncertainties of Doppler velocity (spectrum width) are 2.2times (1.6 times) larger at the vertical channel. The reflectivity calibration of KCR is also performedusing X-band vertically pointing radar (VertiX) and 2-dimensional video disdrometer(2DVD). Since the monitoring of calibration values is useful to evaluate radar condition, thevariation of calibration is monitored for five rain events. The average of calibration bias is10.77 dBZ and standard deviation is 3.69 dB. Finally, the statistical characteristics of cloudproperties have been investigated during two months in autumn using calibrated reflectivity. The percentage of clouds is about 26% and 16% on September to October. However, furtheranalyses are required to derive general characteristics of autumn cloud in Korea.
Abstract
The Ka-band cloud radar (KCR) has been operated by the National Institute ofMeteorological Research (NIMR) of Korea Meteorological Administration (KMA) at BoseongNational Center for Intensive Observation of severe weather since 2013. Evaluation of dataquality is an essential process to further analyze cloud information. In this study, we estimatethe measurement error and the sampling uncertainty to evaluate data quality. By using verticallypointing data, the statistical uncertainty is obtained by calculating the standard deviationof each radar parameter. The statistical uncertainties decrease as functions of sampling number. The statistical uncertainties of horizontal and vertical reflectivities are identical (0.28 dB). On the other hand, the statistical uncertainties of Doppler velocity (spectrum width) are 2.2times (1.6 times) larger at the vertical channel. The reflectivity calibration of KCR is also performedusing X-band vertically pointing radar (VertiX) and 2-dimensional video disdrometer(2DVD). Since the monitoring of calibration values is useful to evaluate radar condition, thevariation of calibration is monitored for five rain events. The average of calibration bias is10.77 dBZ and standard deviation is 3.69 dB. Finally, the statistical characteristics of cloudproperties have been investigated during two months in autumn using calibrated reflectivity. The percentage of clouds is about 26% and 16% on September to October. However, furtheranalyses are required to derive general characteristics of autumn cloud in Korea.
참고문헌 (23)
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