Important features of pollutant transport and diffusion in complex terrain/coastal settings revealed by airborne lidar

Our knowledge of transport and dispersion of air pollutants in complicated terrain or complex coastal/lakeshore settings is considerably less than that over simple, level terrain. This is largely because of induced microscale and mesoscale flows and lack of representative sites for ground-based monitors and inaccessibility for airborne in situ platforms. This knowledge, for instance, is required to improve the formulations of and validate air quality models, which in turn are used to develop strategies for alleviation of air pollution problems. Remote sensing devices, particularly those from aircraft or satellite platforms, have the capability of providing measurements with the requisite space and time detail for the understanding of the physical governing processes in such locales and also for improving and using air quality models for strategy development. One such device, the airborne lidar, has been widely used during field investigations to study pollutant distributions and attendant boundary layer structure and physical processes in relevant locales as various parts of Southern California. Each of these field investigations focussed on specific aspects or features of pollutant transport and diffusion. This paper summarizes pertinent and presents explicit examples of these aspects or features.