Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization

Joel Aholi; Kennedy Obiero; Mary Makokha

doi:10.26650/ijegeo.1861107

Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization

Abstract

This study examines the influence of climate variability and land use/land cover (LULC) changes on rainfall dynamics and hydrological responses within the Zaaba River watershed in western Kenya. Long-term daily rainfall and discharge data (1991–2020) were analyzed using Mann–Kendall trend tests and Sen’s slope estimator to determine temporal variability and trends. Spatial analysis of LULC changes was conducted using Landsat imagery (2001, 2011, and 2020) through supervised classification techniques in GIS. Results indicate a slight but statistically significant increasing trend in seasonal (MAM and OND) and annual rainfall, suggesting potential increases in water availability alongside heightened flood risks. However, substantial LULC transformations were observed, including a decline in agricultural and riparian vegetation and a marked expansion of built-up areas. These changes have altered watershed hydrological processes by reducing infiltration and evapotranspiration while increasing surface runoff and river discharge variability. Correlation analysis reveals that both rainfall variability and anthropogenic land transformations signif icantly influence streamflow patterns. The combined effects of climate variability and LULC change have increased the vulnerability of water resources and agricultural systems within the basin. The study highlights the need for integrated watershed management strategies, including vegetation restoration, sustainable land use planning, and adaptive water resource management, to enhance resilience to climate variability and ensure sustainable water utilization.

Keywords

References

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Details

Primary Language

English

Subjects

Physical Geography and Environmental Geology (Other)

Journal Section

Research Article

Authors

Joel Aholi ^*
0009-0000-8937-9296
Kenya

Kennedy Obiero This is me
0000-0003-3949-2703
Kenya

Mary Makokha
0000-0003-1755-8089
Kenya

Publication Date

June 19, 2026

Submission Date

January 11, 2026

Acceptance Date

March 28, 2026

Published in Issue

Year 2026 Volume: 13 Number: 2

DOI

https://doi.org/10.26650/ijegeo.1861107

IZ

https://izlik.org/JA59MB22EH

Cite

RIS / Bibtex

APA

Aholi, J., Obiero, K., & Makokha, M. (2026). Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization. International Journal of Environment and Geoinformatics, 13(2), 129-135. https://doi.org/10.26650/ijegeo.1861107

AMA

1.Aholi J, Obiero K, Makokha M. Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization. IJEGEO. 2026;13(2):129-135. doi:10.26650/ijegeo.1861107

Chicago

Aholi, Joel, Kennedy Obiero, and Mary Makokha. 2026. “Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization”. International Journal of Environment and Geoinformatics 13 (2): 129-35. https://doi.org/10.26650/ijegeo.1861107.

EndNote

Aholi J, Obiero K, Makokha M (June 1, 2026) Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization. International Journal of Environment and Geoinformatics 13 2 129–135.

IEEE

[1]J. Aholi, K. Obiero, and M. Makokha, “Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization”, IJEGEO, vol. 13, no. 2, pp. 129–135, June 2026, doi: 10.26650/ijegeo.1861107.

ISNAD

Aholi, Joel - Obiero, Kennedy - Makokha, Mary. “Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization”. International Journal of Environment and Geoinformatics 13/2 (June 1, 2026): 129-135. https://doi.org/10.26650/ijegeo.1861107.

JAMA

1.Aholi J, Obiero K, Makokha M. Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization. IJEGEO. 2026;13:129–135.

MLA

Aholi, Joel, et al. “Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization”. International Journal of Environment and Geoinformatics, vol. 13, no. 2, June 2026, pp. 129-35, doi:10.26650/ijegeo.1861107.

Vancouver

1.Joel Aholi, Kennedy Obiero, Mary Makokha. Effect of Climate Variability on Rainfall Dynamics in a River Basin: Implications for Sustainable Water Resources Utilization. IJEGEO. 2026 Jun. 1;13(2):129-35. doi:10.26650/ijegeo.1861107