Solar eclipse effects observed in the planetary boundary layer over a desert

Boundary-layer meteorological measurements were made before, during, and after the May 10, 1994 partial (94%) solar eclipse over the desert at the Atmospheric Profiler Research Facility at White Sands Missile Range, New Mexico, U.S.A. A large number of sensors were located in the middle of the Tularosa Basin to measure mean and turbulent quantities and the refractive index structure parameter (C-n(2)). This event permitted a rare opportunity to measure, examine, and document the effects upon the atmospheric boundary layer of a sudden cut-off and subsequent turn-on of the sun's radiant energy. At the peak of the eclipse, which occurred for more than three hours, all of the heat exchange parameters were affected, the turbulent processes were diminished, and the refractive index structure parameter decreased dramatically. A time-height display from the FM-CW radar shows a Kelvin-Helmholtz wave that developed during the eclipse. The results of several analyses are presented to document and characterize the eclipse-modified boundary layer.