Rainfall and Temperature Characteristics in Kibwezi West Sub-County, Kenya

Abstract

Climate variability and change are among the numerous variables that negatively impact the economies of many countries worldwide, especially in Sub-Sahara Africa where over 80% of the population is heavily dependent on rain-fed agriculture for their livelihood. Kenya is an agriculture-based economy and therefore rainfall performance remains critical to her social-economic development. This called for the need to undertake this study in one of the arid and semi-arid (ASALs) regions of the country where agriculture is the primary economic activity. This study analyzed both annual rainfall and annual average temperature characteristics in Kibwezi West sub-county, Kenya. The findings showed that between 1993 and 2023 dry conditions were experienced in 61.3% of the period translating to a drought cycle of once every 2 years, which negatively impacted food security. With a CV of 32%, this implied that annual rainfall was less predictable, heightening the Sub-County’s vulnerability to drought. A PCI value of 17.1 indicated that annual rainfall was not evenly distributed throughout the year. Rainfall was only concentrated in April, May, November and December with most of the other months being dry. The linear regression analysis revealed a negative slope value (-0.4), indicating a downward trend. Specifically, this means that for each passing year, annual rainfall decreased by 0.4mm. For the annual average temperature trend, there was a generally increasing trend of 0.03 degrees per year. These findings suggest that the sub-county was already experiencing climate change and therefore there is a need for the development of climate change adaptation strategies, such as growing drought-tolerant crops to enhance food security and community resilience to climate shocks.