LONG-TERM GOALS

The ultimate goal of this project is to demonstrate that when tropical cyclones (TCs) are present in the atmosphere, a multi-scale approach for data asssimilation can significantly ehnance the analysis and forecast of the TC and the forecast of the effects of the TC on the larger scale atmospheric processes (e.g., through the extratropical transition (ET) of the TC into an extratropical cyclone). Our multiscale approach is based on coupling a lower resolution global data assimilation system and a higher resolution limited area data assimilation system for the region where TCs develop and evolve. The coupled approach has the potential to lead to a better utilization of the computer resources in atmospheric modeling. OBJECTIVES Ours is the first attempt to use an ensemble-based coupled global-limited-area data assimilation system to improve the analysis and forecast of TCs, and the forecast of the effects of the TCs on the larger scale atmospheric processes. In fact, to the best of our knowledge, we have been the only research group working on the development of a global data assimilation system that uses a higher resolution limited area component to enhance the analysis in a selected region. Our key scientific objectives are to find the optimal configuration of the coupled system and to explore its potentials and limitations