Increasing frequency, severity and duration of droughts in Arid and Semi-Arid Lands in Kenya in the past three decades is a major challenge to survival of agrarian livelihoods and food security in Makueni County. Increasing frequency and severity of droughts in the region are influenced by a number of factors. The Indian Ocean Dipole is the principal factor driving droughts in the lower Eastern region. The influence of the Indian Ocean Sea Surface Temperatures on occurrence of droughts in Makueni is exacerbated by a long coastal contact zone between East African coast and the Indian Ocean coastline. 80% of the Kenya landmass is under Arid and Semi-Arid zones. The study determined the influence of Indian Ocean Dipole on occurrence and nature of droughts in Makueni County, Kenya. The study adopted explanatory sequential mixed methods research design. Indian Ocean Sea Surface Temperature data and rainfall data were collected from the National Oceanic Atmospheric Administration website and Kenya Meteorological Department respectively. Linear regression model was used in data analysis. The study found that Indian Ocean Dipole has a significant influence on the occurrence of droughts in Makueni County. The study established that a reduction in the value of Indian Ocean Sea Surface Temperatures in Western Indian Ocean (10˚S - 10˚N, 50˚ - 70˚E) and East-ern (tropical) Indian Ocean (10˚S - 0˚, 90˚ - 110˚E) leads to a similar reduction in the amount of rainfall hence drought episodes in Makueni County. On the other hand, an increase in the value of Indian Ocean Sea Surface Temperatures leads to a similar increase in amount of rainfall in Makueni County. Variation in Indian Ocean Sea Surface Temperature re-sulted in erratic, unpredictable and fluctuating rainfall patterns accompanied by 5 mild and 20 near-normal drought episodes with multi-year droughts between 2003 and 2009. Increasing trend of seasonal droughts was also established due to declining March-April-May seasonal rainfall. An upward trend in October-November-December seasonal rainfall was also established. This study recommends studies on the influence of anthropogenic forcing on drought occurrence in Arid and Semi-Arid Lands and other agroecological zones in Kenya.
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