A Precipitation Retrieval Algorithm for the Himawari Advanced Himawari Imager

This paper presents an algorithm for retrieving surface precipitation rate for the Advanced Himawari Imager (AHI). AHIs are aboard the Japanese geostationary meteorological satellites Himawari 8 and 9. The algorithm employs the neural network method developed for land and sea separately. The coincidentally overlapping AHI observations and the surface precipitation rates from the AMSU MIT Precipitation (AMP) retrieval products are employed for training neural networks and evaluating retrieval accuracies. Results show that AHI retrievals agree well with AMP surface precipitation rates, where the correlation coefficient is 0.65. The retrievals are useful for all ranges of surface precipitation rate for both land and sea, where those over sea are more accurate. The precipitation retrieval algorithm developed in this study can provide useful retrieved surface precipitation rates every 10 minutes, which are particularly useful for observing convective precipitation and tropical cyclones.