Rainfall Variability over Kenya (1950-2012) – Abstract

Journal of Environmental and Agricultural Sciences (JEAS). Sagero et al., 2018. Volume 14: 1-15

Open Access – Research Article

Investigation of Rainfall Variability over Kenya (1950-2012)

Philip Obaigwa Sagero 1,2,* Chris A. Shisanya1 , George L. Makokha1
1Department of Geography, Kenyatta University, P.O Box 43844-00100, Nairobi, Kenya
2 Kenya Meteorological Departments, P.O. Box 30259-00100, Nairobi, Kenya

Abstract: This study investigates the rainfall variability from 33 stations, for a period of 63 years (1950 – 2012) over Kenya. Coefficient of Variability and non-parametric MannKendall test at 5% level of significance was used to assess the variability and trend, respectively. The Sen’s slope estimator was then used to find the magnitude of the changeover the time period. It was observed that October to December season had a high inter-annual variability, with most stations having greater than 50% of the Coefficient of Variation compared to March to May season, which had only 4 stations with over 50% Coefficient of Variation. Insignificant decreasing trend was noted during the March – May rains, while insignificant increasing trend in October – December rains. On a spatial scale, a negative trend was noted in the northern part of the country and the opposite condition was noted in western regions of the country, around Lake Victoria area. The results indicate a likelihood of negative impact on sectors of the economy that relay on rainfall, because of negative trend in March – May long rains, which accounts for most of rains received annually in Kenya. Although the October – December rains have an increasing trend, they are unreliable due to high inter-annual variability.
Keywords: Rainfall; climate change; Trend analysis; Mann-Kendall; Coefficient of Variation.

*Corresponding author: Philip Obaigwa Sagero, E-mail: psagero@meteo.go.ke,  phsagero@gmail.com

Cite this article as:

Sagero, P.O., C.A. Shisanya and G.L. Makokha. 2018. Investigation of rainfall variability over Kenya (1950-2012). Journal of Environmental and Agricultural Sciences. 14: 01-15. [Abstract] [View Full-Text [Citations]

Title: Investigation of Rainfall Variability Over Kenya (1950-2012)

Authors: Philip Obaigwa Sagero, Chris A. Shisanya, George L. Makokha

Pages: 01-15

Copyright © Sagero et al., 2018. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium provided the original author and source are appropriately cited and credited.

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