Application of Lidar Data in the Assessment of Observed and Model Output Temperature Soundings During the Pacific 2001 Field Study.

Surface and airborne lidar, along with upper air soundings and model derived soundings were examined over the course of the Pacific 2001 Air Quality Field Study. The general region of interest in this report is the Georgia Basin with a focus on the Lower Fraser Valley of British Columbia. Data included the following: RASCAL (Rapid Acquisition SCanning Aerosol Lidar), a surface-based scanning lidar facility at the Langley Lochiel site, operating close to 16 hours each day; AERIAL (AERosol Imaging Airborne Lidar), a simultaneous upward/downward airborne lidar system providing 9 flights during the field study; radiosondes, released 4 times daily from the Langley Poppy site; and once-daily 3.3 km resolution MC2 (Mesoscale Compressible Community weather prediction) model output. Methods of diagnosing mixing heights amongst the various datasets are outlined. The higher resolution lidar data provides a means of calibrating mixing heights from radiosondes and also allows a means of evaluating model derived soundings. Results show that in most cases there is good agreement amongst the various sources of data. This data is then used to demonstrate the variation of mixing height with sea breeze activity over the Lower Fraser Valley.