Determining the onset and cessation of seasonal rains in Malawi

Abstract

The country ofMalawi has a sub-tropical climate, which is relatively dry and strongly seasonal. The warm-wet seasonal stretches from November to April, during which 95% of the annual precipitation takes place. A cool, dry winter season usually starts from May to August and a hot, dry season is experienced from September up to October. Over the years there has been some slight changes on the onset of rainfall, this has affected the country of Malawi greatly since it fully depends on rain fed agriculture. The onset and cessation dates were generated by using Instat. In the northern region the result shows that on average the onset occurred between 5th-18 December. Cessation on average occurred between 19th April-2nd May. In the central region of the study area the results shows that on average the onset occurred between 7th -10th December. Cessation on average occurred between 8th-20th April. In the southern region on average the onset occurred between 25thNovember -2nd December. Cessation on average occurred between 5th April- 3rd May. The study also showed increasing/decreasing trends in the onset/cessation dates. When we have late onset and early cessation, it means that the length of growing season is decreasing.