Estimation of atmospheric turbidity over Adrar city in Algeria

Abstract

Under a cloudless sky atmospheric turbidity causes attenuation of solar radiation reaching the earth's surface. The Linke’s turbidity factor (TL) and the Ångström’s turbidity coefficients (β) are the most frequently used atmospheric turbidity indices. TL and β are a key input for several models that assess the solar radiation under clear skies. In this paper, the Linke and Ångström turbidities were obtained from radiometric and meteorological data recorded in the Sahara desert area of Adrar region, Algeria, during October 2012–May 2015. It is observed that there is a high correlation between atmospheric turbidity caused by aerosols and meteorological parameters. A comparison has also been carried out with results acquired in Ghardaïa and Tamanrasset regions. In addition to verify the appropriateness of the theoretical Linke turbidity factor formula presented in Algerian solar atlas, the monthly mean theoretical values are compared with the experimental monthly average values. Keywords: Solar radiation, Atmospheric turbidity, Linke factor, Ångström coefficient, Adrar