USE OF AIRBORNE LIDAR TO DETERMINE AEROSOL SOURCES AND MOVEMENT IN THE LOWER FRASER VALLEY (LFV), BC

A major oxidants held experiment (Pacific'93) was carried out in Vanco uver, British Columbia, in July/August 1993. The purpose of the experi ment was to provide data on the three-dimensional extent and movement of pollutants in a complex topographic regime so that predictive pollu tant models could be assessed. As part of the study, 1.064 mu m downwa rd pointing lidar was flown on the National Research Council of Canada (NRCC) Convair 580 aircraft. These data have been used to visualize t he aerosol pollutant structure throughout the lower Fraser Valley. Whi le the majority of the pollution in the valley is from the urbanised s ector around Vancouver, there are at least seven additional point sour ce emitters which impact the valley in a significant way. The data are compared with in situ particle probe data from the aircraft when flyi ng at low level and with surface sensors. Aerosol backscatter ratio at 500 m altitude is about 25-60% larger than predictions from a Mie sca ttering model using the in situ particle probe size distributions. Cro wn copyright (C) 1997 Published by Elsevier Science Ltd.