Nocturnal Planetary Boundary Layer Structure and Turbulence Episodes during the Project STABLE Field Program

Abstract

Abstract This paper summarizes the results of meteorological and dispersion measurements during Savannah River Laboratory's Project STABLE (Stable Boundary Layer Experiment) field program. The field program took place at the Savannah River site on three nights during 12–17 April 1988. Meteorological data were collected from a 304-m tower, an array of eight 60-m towers, two sodars, a tethersonde, and a sonic anemometer. Based on the classification scheme of Kurzeja et al. (1991) the first and third nights were classified as unsteady type IV nights because of the passage of microfronts on each night. The second night exhibited a continuous level of high turbulence with a weak surface-based inversion and was classified as a steady type III night. The third night was especially interesting because of the considerable directional wind shear with height and the occurrence of two turbulent episodes. The directional shear may have been related to the passage of a high pressure center during the night. The turbule...