The Joint Urban 2003 (JU2003) Experiment combined meteorological observations with tracer measurements to evaluate and improve modeling of dispersion in urban areas. As part of the array of instruments that were deployed in the Oklahoma City central business district during July of 2003, several meteorological towers were deployed in a street canyon along Park Avenue, between Broadway and Robinson Streets. These towers were located along Park Avenue on both sides, with ultra-sonic anemometers at several levels. A surface energy balance was obtained at a tower on the north side of Park Avenue by including radiometric instruments, infrared thermometers and ground flux heat plates imbedded within the road surface.

The surface energy balance influences the circulation within the street canyon. Building shadows affect the incoming solar radiation, and therefore influence the surface forcing in the canyon. Differential surface forcing creates local, canyon-scale circulation which ultimately affects the dispersion of material within the canyon and exchange of material in to and out of the canyon. Observations of the surface energy balance are correlated with the circulation in the urban canyon.

This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.