MANN-KENDALL AND SEN'S SLOPE ESTIMATOR STATISTICAL TESTS FOR ANALYZING CHANGES IN METEOROLOGICAL VARIABLES IN KWALE COUNTY, KENYA

  • Kevin Morang'a Department of Environmental Science and Education, Kenyatta University, Kenya
  • Dr. Ezekiel Ndun Department of Environmental Science and Education, Kenyatta University, Kenya
  • Dr. Dan Adino Department of Department of Anthropology and Gender Studies, University of Nairobi, Kenya
Keywords: climate change, precipitation trends, temperature trends, Sen's slope, Mann-Kendall

Abstract

Temperature and Precipitation variables were examined for 40 years in the four sub-counties of Kwale County in Kenya between 1980 and 2022. The statistical significance of the meteorological data was utilized to evaluate whether a positive or negative trend existed using the non-parametric Sen's and Mann-Kendall approaches. Annual temperature trends are positive and statistically significant for Kinango (ZS=0.692 , Qmed=0.049, p<0.001); Lunga Lunga (ZS=0.677 , Qmed=0.040, p<0.001); Msambweni (ZS=0.610 , Qmed=0.042, p<0.001) and; Matuga (ZS=0.641 , Qmed=0.043, p<0.001). However, the annual precipitation trends not statistically significant for Kinango (ZS=0.026, Qmed=0.003, p>0.005); Lunga Lunga (ZS=0.210 , Qmed=0.017, p>0.001); Msambweni (ZS=-0.077, Qmed=-0.011, p>0.001) and; Matuga (ZS=0.146, Qmed=0.011, p>0.001). Precipitation has not significantly changed in Kinango, Msambweni, Lunga Lunga, and Matuga. It is only in Lunga Lunga during June that precipitation changed significantly and in November for Lunga Lunga. Msambweni showed a slight positive change. In Matuga in november, there is a substantial positive upsurge in precipitation. From the study, climate change is occurring in Kwale County, Kenya.

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Published
2022-08-22
How to Cite
Morang’a, K., Ndun, D. E., & Adino, D. D. (2022). MANN-KENDALL AND SEN’S SLOPE ESTIMATOR STATISTICAL TESTS FOR ANALYZING CHANGES IN METEOROLOGICAL VARIABLES IN KWALE COUNTY, KENYA. IJRDO Journal of Forestry, Wild Life and Environment , 8(8), 1-12. Retrieved from http://webdisk.ijrdo.org/index.php/few/article/view/5270
Issue
Vol. 8 No. 8 (2022): Journal of Forestry, Wild Life and Environment
Section
Articles