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With the development of society, economy, and military, the demand for very short-term precipitation forecasting in far sea areas is becoming increasingly strong. In response to the low accuracy of precipitation forecasting, a correction method integrating FY-4 infrared cloud images for precipitation forecasting in the future 0~4 hour was proposed for the areas without weather radar such as the far sea. Firstly, based on the high-resolution prediction product from the numerical weather model WRF and the radiation transfer model RTTOV, the FY-4 infrared (10.3~11.3μm) forecast cloud image (bright temperature) was made by forward modeling method; Secondly, compared with the FY-4 observation cloud images, the evolution information of prediction errors of brightness temperature in the past -2~0 hours was obtained by using optical flow method. Next, three different schemes were proposed to apply the error evolution information of the predicted brightness temperature in the past -2~0 hours to correct the predicted brightness temperature in the future 0~4 hours; Finally, on the basis of brightness temperature correction with good results, three different correction schemes of forecast precipitation were proposed and analyzed. The results show that: 1) the average values of the root mean square error, average absolute error, and correlation coefficient of the predicted brightness temperature within 24 hours are 23.7K, 15.8K, and 0.45, respectively, showing a significant correlation between the predicted and observed brightness temperature; 2) after the correction, the average root mean square error of the predicted brightness temperature in the future 0~4 hours decreased by 5.4K, the average absolute error decreased by 3.4K, and the average correlation coefficient increased by 0.19; 3) after the correction, the TS score of predicted precipitation in the future 0~4 hours has significantly improved too. The research results will not only provide high-quality infrared forecast cloud images, but also improve the accuracy of very short-term precipitation forecasting in the far sea areas, and provide reference for improving the accuracy of precipitation forecasting in other regions such as the plateau and western regions of China.
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