Abstract
The ECLATS experiment was conducted in order to investigate the influence of radiative processes on the dynamics of the atmospheric boundary layer during its diurnal evolution. This experiment was carried out over Niger, near Niamey, by measuring continuously the energy balance at ground level and by using an instrumented aircraft for turbulence, radiative fluxes and aerosol measurements in the boundary layer during dusty conditions (‘brumes sèches’). This paper is restricted to an analysis of the turbulent structure in the homogeneous and stationary convective boundary layer. The turbulence moments for kinetic energy and the spectral characteristics of the vertical velocity are discussed. These results are compared with a set of data obtained for clear convective boundary layers. The differences observed are quite important and seem, at least in part, due to radiative processes (infrared radiative divergence in the surface layer and absorption of solar radiation in the boundary layer).
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Druilhet, A., Durand, P. Etude de la couche limite convective sahelienne en presence de brumes seches (Expérience ECLATS). Boundary-Layer Meteorol 28, 51–77 (1984). https://doi.org/10.1007/BF00119456
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DOI: https://doi.org/10.1007/BF00119456