DAY-LENGTH AND EXTRATERRESTRIAL RADIATION FOR SUDAN: A COMPARATIVE STUDY

Abstract

A comparative study of estimating the day-length, S 0, and extraterrestrial radiation, H, is conducted, with special reference to Sudan. Due to the definitions of the formulae of Cooper and Hay, differences in S 0-values are normal; however, the former formula revealed excellent agreement with data on the duration between sunrise and sunset. Hence, the paper recommends adopting Cooper's method for computing S 0 for Sudan. With regard to H 0, the use of the average days for the months, as recommended by Klein, has depicted no substantial errors. This has also been found true for day-length computations. The study further accentuates that the amount of solar energy available in Sudan is significantly large to be used for industrial purposes.