First Steps Toward a Coupled Ocean–Atmosphere Data Assimilation System at the Canadian Meteorological Center

Recently, Environment and Climate Change Canada (ECCC) has shown a significant positive impact on atmospheric forecasts using the coupled ocean-atmosphere NEMO-GEM model. That improved forecast system will be implemented operationally by the time of the conference. However, the data assimilation part of the system remains to be uncoupled. As a first step toward that goal, the trial fields from the coupled forecast model are used by the atmospheric data assimilation system while keeping uncoupled the ocean data assimilation. In the presentation, we will show how the evolving sea surface temperature (SST) influences the satellite radiance assimilation in terms of innovation statistics and how the coupling modifies SST increments proposed by the radiance assimilation. The impact on atmospheric forecasts will be evaluated. Next steps toward stronger coupling will be highlighted.