Evaluation of WRF Performance for Depicting Orographically-Induced Gravity Waves in the Stratosphere

摘要

Orographically-induced gravity (buoyancy) waves can propagate through the tropopause to the lower stratosphere causing disruptions to high altitude aircraft operations. In order to forecast this high altitude turbulence (HAT) in real time, there is a need to determine optimal model nesting, vertical structure, upper boundary conditions and diffusion to be able to detect these situations. Besides investigating the abovementioned model options, the WRF-ARW will be closely configured to the operational version used by the Air Force Weather Agency (AFWA). To perform the model evaluation, a case from a field experiment conducted at the Observatoire de Haute-Provence (OHP) in southeastern France between 22 November and 5 December 2004 will be examined. Using a forecast initialized from 00 UTC 23 November, it will be determined how well waves generated by a north/south Mistral type flow over the French Alps north of OHP are represented by the model.