The Nature of Climate Variability and Impacts of Drought Over Kwazulu-Natal, South Africa

Recent drought in southern Africa has renewed concern about natural and possible man-made climate change. A large majority of the population relies on agriculture at a subsistence level for food, or at a more advanced level to generate income, and therefore are susceptible to inter-annual and intra-seasonal variability in rainfall and climate. Most drought-related studies in South Africa describe its temporal behaviour and the associated anomalies over the country and surrounding oceans. There is dearth of research on drought impacts, especially those integrating the human and physical aspects. Here we describe the magnitude of climate variability over KwaZulu-Natal and outline drought impacts on agriculture and water resources of the province. The analysis points to an increase in the frequency of prolonged below normal rainfall and above-normal temperatures over the past four decades. The sensitivity of maize and sugar cane yield to sustained climate departures is studied in relation to the economy and food production. Water resources are also adversely affected by drought. Annual inflow levels to Midmar Dam near Durban declines from 108 m3 in 1991 to 106 m3 during 1993. The understanding of climate variability and abnormally below (and above) rainfall scenarios is vital for seasonal forecasting so that effective, scientifically sound and defensible decisions are made in response to timely warnings issued for these hazards.