Determination of atmospheric turbidity in Bangladesh

Atmospheric turbidity parameters have been determined following Angstrom's method at three locations in Bangladesh namely, Dhaka city (23.7 degrees N) and two rural locations, Haripur (26.03 degrees N) and Sripur (24.11 degrees N). The parameters were obtained from direct solar radiation data for specific spectral regions and for the whole spectrum as measured using a normal incidence pyrheliometer provided with cut-off glass filters. A considerable variation of Angstrom's turbidity parameters for Dhaka over the year was observed with a maximum value in March. The value for Sripur for the month of March was somewhat lower and the value for Haripur for the month of April was not much different from that of Dhaka. Linke turbidity factor T-L was also determined using the new value of solar constant 1367 W/m(2) for all three locations. (C) 2000 Elsevier Science Ltd. All rights reserved.