A gravity wave analysis near to the Andes Range from GPS radio occultation data and mesoscale numerical simulations: Two case studies

The mesoscale numerical WRF (Weather Research and Forecasting) 2.1.2 model was used to simulate the atmospheric parameters during two representative RO events showing apparent intense WA in this region. The significance of the relative position of the RO lines of sight, the line of tangent points and GW phase surfaces during each event is discussed in relation with the apparent WA detected. The GPS RO technique may not be by itself reliable enough to quantify and locate WA of single events. Nevertheless, it should be considered a useful tool to observe the global WA from statistical studies. We also discuss the relative contribution of high and medium intrinsic frequency mountain waves regularly observed, coexisting with inertio gravity waves, their origin and propagation characteristics.