Performance and Evaluation of the Global Modeling and Assimilation Office Observing System Simulation Experiment

The GMAO OSSE includes an adjoint tool that can be used to estimate the impact of al l ingested observing types on the 24-hour forecast skil l simultaneously. The adjoint observation impact in the OSSE is compared to the real data observation impact in Figure 4. While the total observation impact in the OSSE is smaller than for real data (left panel), the relative fraction of impact for each data type is general ly well represented in the OSSE (right panel). This al lows qualitative statements to be made about the potential impact of new observing systems in the OSSE by comparing the impacts of different data types.