Abstract
The measurements obtained during the ECLATS experiment were used in order to determine the surface energy budget of the Sahel region (Niamey, Niger). This expedition was carried out from November 15 to December 10, 1980, during the dry period. Some data were collected by an instrumented aircraft, from which the turbulent fluxes were obtained in the boundary layer around midday; data were also collected at a surface station in order to estimate the surface energy budget continuously by the profile method. The aircraft measurements show the homogeneity of the vertical fluxes over large areas, allowing generalization to the bushy steppe of the Sahel region. The mean diurnal cycle of the energy budget is characterized by high values of ground heat flux and weak values of latent heat flux (deduced from the balance of the energy budget). This cycle is compared with that of the Koorin expedition, performed in similar conditions (tropical savanna in the dry period). We compare the three midday budgets: during Koorin; during ECLATS, at the ground station, and with the aircraft. The important differences that appear in the net radiative flux are explained by the difference in surface albedo.
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Ecole des Sciences, Université de Niamey, B.P. 10662 Niamey, Niger.
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Durand, P., Frangi, JP. & Druilhet, A. Energy budget for the Sahel surface layer during the ECLATS experiment. Boundary-Layer Meteorol 42, 27–42 (1988). https://doi.org/10.1007/BF00119873
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DOI: https://doi.org/10.1007/BF00119873