Analysis of Rainfall and Temperature Variability in Kieni; Nyeri County

Abstract

Analysis of climate trend and projection is an important exercise because it can help in designing of climate change adaptation strategies and inform the options that are available for uptake by communities. This study considered the analysis of both precipitation and temperature in Kieni sub-county. The Mann-Kendall test was applied to test for significant trends. In this analysis the null hypothesis was tested at 95% confidence level. The datasets used were obtained from Kenya Meteorological Department (KMD) recognized weather stations - Sasini Farm; Munyaka Met Station and Naromoru Park Gate Met Station. These datasets included precipitation (1985-2015) and temperature (1991-2015). The study shows rainfall variations between the weather stations. The long-term mean annual rainfall estimated during 1985-2015 was 870.29 mm for Sasini Farm (Mweiga); 644.56 mm for Munyaka and 1664 mm Naromuro Park gate weather station in Naromuro. Results revealed a more successful short rain season (OND) and decline in long rains (MAM) in the area. Temperature trend analysis revealed that both the maximum and minimum average temperature has been reducing since 1991 up to around post 2010 where it started rising slowly.