Assessing the spatial and temporal characteristics of rainfall over the Southern region Of Malawi

Abstract

An understanding of temporal and spatial characteristics of rainfall is central to resources planning and management especially with evidences of climate change and variability. There are strong indications that rainfall changes are already taking place on the local, regional and global scales associated with global warming. The main objective of the project was to assess rainfall characteristics over the Southern Region of Malawi. In order to achieve the objectives, the rainfall data was subjected to various analyses including quality control. Forty-two years of daily rainfall data (1971-2012) from 9 stations within the region was analysed inorder to observe the characteristics of rainfall such as the onset and cessation, rain days, seasonal, annual, spatial and temporal rainfall distribution. The core methodology used in analysis of rainfall trends and variability was the time series analysis, single mass curve and spatial analysis for rainfall distribution. Other tools used were surfer application for spatial rainfall analysis and Instat climatic statistical application for determination of onset, cessation and length of growing season. In Malawi, agricultural and electricity generation productions largely depends on rain. The rainfall pattern in the area is highly variable and is associated with extreme events which cause flooding in certain areas of the region. Flooding has led to loss of property and infrastructure and to a higher extent has led to food insecurity over the region. These occurrences have negative effects on the country’s economy. The results of this study have shown that there are decreasing trends in rainfall data but they are not though insignificant. The results have also shown that the rainfall in the area is variable and has varying onset and cessation dates. The growing season has also been reduced due to the decreased number of rain days that are being experienced over the region hence the need for effective planning and proper resource management inoder to realize positive productivity with the available rain.