Micrometeorology of Slope Flows in a Tributary Canyon during the 1984 ASCOT Experiment

Abstract

Micrometeorological data collected on towers are used to document slope flows on the sidewalls of main and tributary canyons. Six weeks of low-frequency, continuous data provide a background for comparison with data obtained during two nocturnal experiments. This comparison demonstrates the relatively strong drainage conditions during the experiments. The expected low-level wind speed maxima were observed, along with mass flux divergence down the 35° slopes. Profiles of turbulent kinetic energy, derived from high-frequency data taken during the two experiments, show a maximum near the canyon sidewalls. These features of the slope flows are disturbed occasionally on the main valley sidewall when the main valley flow impacts the sidewall; such disturbances are not observed in the tributary canyon.