Rеvuе des Energies Renouvelables
Volume 16, Numéro 4, Pages 741-748
2013-12-31

Estimation Of The Angström Coefficient Over Ghardaïa City

Authors : Djafer D. .

Abstract

Atmospheric turbidity over Ghardaïa city is investigated using the Angström coefficient. Its values are derived using five years (2004-2008) of data. They show a seasonal trend along the year with maximum values around summer months and minimum ones around winter months. The annual average value varied between 0.079 and 0.105. The daily average values were less than 0.1, between 0.1 and 0.2 and exceeded 0.2 for 64.6 %, 33.8 % and 1.6 % of the cloudless days respectively. This result reveals that for 64.6 % of the cloudless days the sky over Ghardaïa city was clean to clear, for 33.8 % was clear to turbid and for 1.6 % was turbid to very turbid.

Keywords

Solar radiation, Turbidity parameters, Angström coefficient, Linke factor.