Assessment of the Impact of ABI Radiance Assimilation NWP Skill

The Advanced Baseline Imager (ABI) on board GOES-16, which was set to become GOES-EAST (positioned at 75 degrees west) on November 19, 2016, represents a new era for a United States (US) geostationary operational environmental satellite (GOES) imager to provide more visible, near-infrared and infrared channels at high spatial and temporal resolutions than all the previous US GOES imagers. In this study, radiance observations of the ten ABI infrared channels are assimilated into the Advanced Research Weather Research and Forecast (ARW) model through the National Centers for Environmental Prediction Gridpoint Statistical Interpolation (GSI) analysis system. Firstly, the cloud- and precipitation-affected radiances are identified and separated from clear radiances using an infrared only cloud detection algorithm that works in both day and night. Secondly, the biases of the ABI brightness temperatures for all infrared channels between observations and model simulations are quantified using the Community Radiative Transfer Model (CRTM). The ABI biases vary with channel numbers and are less than 0.6 K for all the infrared channels over ocean under clear-sky conditions. Finally, impacts of ABI data assimilation on quantitative precipitation forecasts (QPFs) over the continental US in the following two setups: one assimilating all ten ABI infrared channels (ABIA) and the other assimilating only four GOES-like ABI channels (ABIG). It is demonstrated that the ABIA experiment generated a larger improvement on QPFs due to it generating a wetter atmosphere in the middle and low troposphere over both the US continent and the ocean off the southeast coast of US than the ABIG experiment than the ABIG and a control experiment without assimilating any AHI channel.