Impacts of Doppler Radial Wind Assimilation in the GFS with a Global Observing System Simulation Experiment

Doppler radial winds have been an underutilized observation in U.S. operational forecast systems. This has typically been owing to limitations in the formulation of the observation operator, the amount of data thinning via super-obbing, the large disparity between observation density and model resolution, or simple exclusion from assimilation in global modeling systems. At the time of this study, there are no global systems that assimilate radial wind observations and, as a result, there have not been any motivation for data sharing agreements of radial wind observations on a global scale. To overcome the lack of global data access, an observing system simulation experiment was used to test radial wind assimilation in the National Centers for Environmental Prediction’s Global Forecast System (GFS) version 15. This work is a first attempt to assimilate radial wind observations in the GFS. This effort demonstrates the use and benefits of radial wind assimilation in the GFS, a potentially important observation type in future versions of the GFS and provides evidence to pursue data sharing agreements of radial wind observations.