The Uganda Atlas

Climate

U ganda experiences moderate temperatures highest temperatures of over 30 0 C are experienced in the north and northeast of the country while temperatures as low as 4º C are experienced in the highlands of the southwest. Temperatures below 0ºC are registered on the high mountains of Rwenzori and Elgon. The Rwenzori mountains have a permanent ice cap whose size is currently reducing, presumably due to global warming (Uganda Met. Department, 2000; UBOS Statistical Abstracts, 2006). The high temperature records mean there is high potential for water evaporation, which in turn affects the water balance that influences the productivity of the environment, including agriculture, the back bone of Uganda’s economy. Potential evaporation in excess of rainfall leads to water deficit and vice versa. Temperature and rainfall are the most important parameters of climate in Uganda; temperatures are an important factor influencing rainfall and moisture, and in general play a major role in the determination of agro- ecological zones of the country. Most areas experience high potential for water evaporation in excess of rainfall. Therefore, sustainable management of water resources is needed. Water balance analysis in Uganda indicates that both areas of water surplus and water deficit occur. Water surplus occurs only around the high rainfall and low temperature areas of Mt. Rwenzori and Mt. Elgon. The northern shores of Lake Victoria show a slight surplus or an almost even balance. Elsewhere, water deficits of varying degrees occur, generally increasing from south-west to north-east (Langlands 1974). Because of its location around the equator, Uganda experiences equal hours of day light and night throughout the year, indicating that the country receives high solar radiation. However, periods of sunshine vary slightly during the day due to variations in cloud cover. The periods of high sunshine in the country are associated with lower relative humidity and a higher potential for evaporation. For example, the Lake Victoria basin experiences relatively low amounts of sunshine due to the usually cloudy skies while the south western highlands experience the lowest amounts of sunshine due to the unusually high cloud cover and prolonged light rains. throughout the year because of its location astride the equator and on a raised African plateau. The

NEMA 2008

Favourable climate in Manafwa District: Young men carry maize to a grinding mill at the nearby market

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