Assessing the distribution of solar irradiation in Mbarara, Uganda

Abstract

Careful measurements of surface radiation balance components provide, in principle, an important contribution to the understanding of the global energy cycle. They can be used to further improve climatologies of radiative flux components or in the validation of parameterization procedures in weather forecast and climate models. Existing literature lacks information on the distribution of global solar radiation and its two components for locations close to the Equator. The objective of this study is to identity and assess the distributions of global solar irradiation and the ratio of diffuse to direct solar irradiation at a site in Mbarara, Uganda, located at 00°37′S latitude, 30°39′E longitude and at 1413 m altitude. Results have shown that there are bigger and more frequent variations in daily global irradiation at the beginning and towards to the end of the year. The dominance of diffuse over direct solar radiation during the same periods has been demonstrated. The results have been compared with those from a similar measurement site and have shown some similarities and some differences.