Virtual training course: Parametrization of subgrid physical processes

On the basis of simple gravity wave theory, the concepts of sub-grid turbulent form drag, flow blocking, and gravity wave excitation will be introduced. The ECMWF formulations will be described, and the impact will be discussed.
By the end of the session students should be able to:
• Describe the relevant physical mechanisms related to sub-grid orography that have impact on flow in the atmosphere.
• Describe the impact of sub-grid orography.