DYNAMIC CHARACTERISTICS OF REGIONAL FLOWS AROUND THE PYRENEES IN VIEWOF THE PYREX EXPERIMENT - PART-II - SOLUTION OF A LINEAR-MODEL COMPARED TO FIELD-MEASUREMENTS

This paper considers a linear hydrostatic model of a stable, uniform, constant rotational airflow over three-dimensional, elliptic, cross-se ctional families of mountains in a z system. The surface pressure and the winds that are induced around the mountain chain are deduced using Fourier representation in both horizontal directions. The surface pre ssure perturbations and the induced wind intensities are linked to 1) the incoming airmass thermodynamic properties through Froude and Rossb y numbers, 2) the geometrical aspect ratio of the mountain, 3) the dir ection of incidence of the incoming flow relative to the mountain orie ntation, and 4) the Coriolis effect through the Rossby number. The bal ance between the different factors that contribute to the morphology o f the pressure and wind fields was established for northerly and south erly incoming hows that were blocked by an elliptical barrier resembli ng the Pyrenees mountain chain. Fair agreement was found between the r esults of the model and the experimental data collected during PYREX ( Pyrenees experiment) intensive operational periods, with special regar d to the asymmetry of the lateral flow for northerly incoming air mass es.