Trajectory derived from the 3D linear wind field retrieved by a wind-profiler mesoscale network

A key issue in the survey or analysis of pollution episodes lies in the documentation of the turbulent dispersion and transport of the pollutant in the atmospheric boundary layer (ABL). Usually these processes are investigated with numerical modeling. Actually with the rapid development of UHF wind profilers able to provide wind components, turbulent variables, mixing height with a fine time and vertical resolution in the ABL, we can expect in a very near future the set up of regional profiler networks devoted to real time pollution monitoring.

Toward this expectation we present and discuss a methodology, based on measurements made by a wind-profiler mesoscale network, which retrieves the 3D wind field (linear part) used to extract any type of air parcel trajectories. The technique is applied to observations collected during the ESCOMPTE campaign which took place in the early summer 2001 in the Marseille region along the Mediterranean coast, one of the most polluted area in France. Numerical modeling outputs and constant volume balloon trajectories are used to compare and verify the accuracy of this based-radar methodology during sea and land breeze events. These cases studies, characterized by rapid temporal evolution and important spatial variations of the atmospheric fields, are particularly instructive in the analysis of the potentiality of the technique.