Direct assimilation of AHI and ABI infrared radiances in NWP models

The launches of the US Advanced Baseline Imager (ABI) on November 19, 2016 and the Japanese Advanced Himawari Imager (AHI) on October 7, 2014 represented a new era of geostationary operational environmental satellite (GOES) imagers. Both ABI and AHI provide many more channels than any other already launched GOES imagers in the world. In this study, we compare the impacts of assimilating all ABI and/or AHI versus GOES-like infrared channels radiances on regional quantitative precipitation forecasts (QPFs) over US and China, respectively. Positive impacts on QPFs over land are obtained for a typical summer precipitation case by assimilating either all ten AHI infrared channels (AHI-10) or only four GOES-like AHI channels (AHI-4) when compared with a control experiment without assimilating GOES observations (CTRL). It is found that a southwest to northeast oriented band of the atmosphere with high water vapor content that was formed and moved inland with time under the influence of a subtropical high and an eastward propagating middle-latitude trough was responsible for the persistent precipitation in the eastern China of the selected case. The AHI-10 experiment generated larger improvements on QPFs due to it generating a wetter atmosphere in the middle and low troposphere over the ocean off the southeast coast of China than the AHI-4 and CTRL experiments.