【摘 要】
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Calibration error is one of the primary sources of bias in echo intensity measurements by ground-based radar systems.Calibration errors cause data discontinuity between adjacent radars and reduce the effectiveness of the radar system.The Global Precipitat
【机 构】
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Shanghai Typhoon Institute,China Meteorological Administration,Shanghai 200030,Chin;Collaborative In
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Calibration error is one of the primary sources of bias in echo intensity measurements by ground-based radar systems.Calibration errors cause data discontinuity between adjacent radars and reduce the effectiveness of the radar system.The Global Precipitation Measurement Ku-band Precipitation Radar (GPM KuPR) has been shown to provide stable long-term observations.In this study,GPM KuPR observations were converted to S-band approxima-tions,which were then matched spatially and temporally with ground-based radar observations.The measurements of stratiform precipitation below the melting layer collected by the KuPR during Typhoon Ampil were compared with those of multiple radar systems in the Yangtze River Delta to determine the deviations in the echo intensity between the KuPR and the ground-based radar systems.The echo intensity data collected by the ground-based radar systems was corrected using the KuPR observations as reference,and the correction results were verified by comparing them with rain gauge observations.It was found that after the correction,the consistency of the echo intensity measurements of the multiple radar systems improved significantly,and the precipitation estimates based on the revised ground-based radar observations were closer to the rain gauge measurements.
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