Impact of climate change on the rainfall pattern of Klip River catchment in Ladysmith, KwaZulu Natal, South Africa

Abstract

Rainfall trend analysis has been of major focus in the past century because of the attention given to climate change by the science and engineering community. According to some latest studies, rainfall is one of the main parameters in any catchment which plays a significant role in flood frequency, flood control as well as water resources planning and management. Ladysmith town in South Africa is flooded almost every year resulting in loss of lives as well as properties and businesses. Thus, this study aimed at determining the monthly and annual rainfall pattern in relation to climate change. The monthly, seasonal and annual rainfall trends for the period 1985 – 2018 were analyzed using Mann-Kendall test and Sen’s slope estimation. Results of this study indicated a variability in seasonal rainfall, with a rainfall increase during December and January of summer months whose Mann-Kendall test results were 1.88 and 0.73, and a major decrease showed in autumn months (March, April, and May) with Mann-Kendall test values of -2.76, -3.53 and -4.09. Thus, the overall results suggest a minor significant change for both Ladysmith and upstream of the Klip river catchment. Based on the analysis, it can be concluded that climate change has an impact on the rainfall spatial pattern of the study area. This correlates well with similar analysis carried out in other areas around the world.