Retrieval of Micro scale Flow Structures from Dual-Doppler Lidar Data Measured in the Urban Boundary Layer

In the Joint Urban 2003 atmospheric dispersion field experiment held in Oklahoma City, two coherent Doppler lidars, owned by the U.S Army Research Laboratory (ARL) and Arizona State University (ASU), were deployed to gain new insights into the boundary layer transport processes of contaminants in and around cities. This provided an opportunity to evaluate the accuracy of the four-dimensional variational data assimilation (4DVAR) method originally designed for the single lidar data retrieval. The second lidar data provided the cross-beam velocities components which are not available in the previous single lidar retrieval. One objective of this work is to determine the fidelity of the data retrieved from the single Doppler lidar and assess model errors by use of the second lidar data. The other objective is to interpret the retrieved microscale flow structures by comparison with the satellite ground building data.