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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References
Ahmed, M., M. Sultan, J. Wahr and E. Yan. 2014. The use of GRACE data to monitor natural and anthropogenic induced variations in water availability across Africa. Earth-Sci. Rev. 136: 289-300.
Amin, A., W. Nasim, M. Mubeen, S. Sarwar, P. Urich, A. Ahmad, A. Wajid, T. Khaliq, F. Rasul, H.M. Hammad, M.I.A. Rehmani, et al., 2018. Regional climate assessment of precipitation and temperature in Southern Punjab (Pakistan) using SimCLIM climate model for different temporal scales. Theor. Appl. Climatol. 131(1): 121-131.
Anyah, R. O. and F. H. M. Semazzi. 2006. Climate variability over the Greater Horn of Africa based on NCAR AGCM ensemble. Theor. Appl. Climatol. 86: 39–62.
Anyamba, E. K. and P. M. R. Kiangi. 1985. Mean motion fields in East Africa at the level of East African Level Jet Core. Arch. Met. Geoph. Biocl. Sev. B. 36: 29-41.
Asnani and Kinuthia. 1979. Diurnal variation of precipitation in East Africa. Republic of Kenya, Meteorological Dept., Nairobi, Kenya, Research report-No. 8:1-58.
Awuor, C.B., V.A. Orindi and A.O. Adwera. 2008. Climate change and coastal cities: the case of Mombasa, Kenya. Environ. Urbanization. 20(1): 231-242.
Battisti, D.S. and R.L. Naylor. 2009. Historical Warnings of future food insecurity with unprecedented seasonal heat. Science. 323(5911): 240-244.
Ben-Mohamed, A. 2010. Climate Change Risks in Sahelian Africa. Reg. Environ. Chang. 11(1): 109- 117.
Berhane, F., and B. Zaitchik. 2014. Modulation of daily precipitation over East Africa by the Madden-Julian oscillation. J. Climate. 27(15): 6016–6034.
Black, E., J.M. Slingo, and K.R Sperber. 2003. An observational study of the relationship between excessively strong short rains in coastal East Africa and Indian Ocean SST. Monthly Weather Rev. 74–94.
Camberlin, P. and N. Philippon. 2002. The East African March – May Rainy Season : Associated Atmospheric Dynamics and Predictability over the 1968 – 97 Period. J. Climate. 15:1002–1019.
Challinor, A.J., J. Watson, D.B. Lobell, S.M. Howden, D.R. Smith and N. Chhetri. 2014. A meta-analysis of crop yield under climate change and adaptation. Nat. Clim. Change. 4: 287.
Conway, D., E.A. van Garderen, D. Deryng, S. Dorling, T. Krueger, W. Landman, B. Lankford, K. Lebek, T. Osborn, C. Ringler, J. Thurlow, T. Zhu and C. Dalin. 2015. Climate and southern Africa’s water–energy–food nexus. Nat. Clim. Change. 5: 837.
Darand, M., M. Dostkamyan and M.I.A. Rehmani. 2017. Spatial autocorrelation analysis of extreme precipitation in Iran. Russian Meteorol. Hydrol. 42(6): 415-424.
Davies, T. D., C. E. Vincent and A. K. C. Beresford. 1985. July-August rainfall in West-Central Kenya. Int. J. Climatol. 5: 17-33.
Eakin, H. and A.L. Luers. 2006. Assessing the vulnerability of social-environmental systems. Annu. Rev. Environ. Resour. 31: 365-394.
Farmer, G. 1988. Seasonal forecasting of the Kenya Coast short rains 1901-84. J. Climate: 8: 489-497.
Forsythe, N., H.J. Fowler, X.-F. Li, S. Blenkinsop and D. Pritchard. 2017. Karakoram temperature and glacial melt driven by regional atmospheric circulation variability. Nat. Clim. Change. 7: 664.
Funk, C., M.D. Dettinger, J.C. Michaelsen, J.P. Verdin, M.E. Brown, M. Barlow and A. Hoell. 2008. Warming of the Indian Ocean threatens eastern and southern African food security but could be mitigated by agricultural development. Proc. Nat. Acad. Sci. 105: 11081–11086.
Funk, C., M.D. Dettinger, J.C. Michaelsen, J.P. Verdin, M.E. Brown, M. Barlow and A. Hoell. 2008. Warming of the Indian Ocean threatens eastern and southern African food security but could be mitigated by agricultural development. Proc. Nat. Acad. Sci. 105(32): 11081-11086.
Gao, R., F. Li, X. Wang, T. Liu, D. Du and Y. Bai. 2017. Spatiotemporal variations in precipitation across the Chinese Mongolian plateau over the past half century. Atmos. Res. 193: 204-215.
Haile, M. 2005. Weather patterns, food security and humanitarian response in sub-Saharan Africa. Philos. Trans. Royal Soc. B: Biol. Sci. 360(1463): 2169-2182.
Harris, I., P.O. Jones, T.J. Osborn and D.H. Lister. 2014. Updated high-resolution grids of monthly climatic observations – The CRU TS3.10 dataset. Int. J. Climatol. 34: 623–642.
He, J., C. Deser and B.J. Soden. 2017. Atmospheric and oceanic origins of tropical precipitation variability. J. Clim. 30(9): 3197-3217.
Helsel, D.R. and R.M. Hirsch. 2002. Statistical methods. Water resources techniques of water resources investigations, No. 4. U.S. Geological Survey. 522.
Hogan E., A. Shelly and P. Xavier. 2015 The observed and modelled influence of the Madden– Julian Oscillation on East African rainfall. Meteorol Apps. 22: 459–469.
Hulme, M., R. Doherty, T. Ngara, M. New and D. Lister. 2001. African climate change: 1900-2100. Clim. Res. 17: 145-16
Indeje, M., F. H. M. Semazzi, L. Xie, and L. J. Ogallo. 2001. Mechanistic model simulations of the East African Climate using NCAR Regional Climate Model: Influence of large scale orography on the Turkana Low-Level Jet. J. Clim.14: 2710 -2724.
Ininda, J. M. 1995. Numerical stimulation of the influence of sea surface temperatures (SST) anomalies on East African seasonal rainfall. Ph.D. Thesis, University of Nairobi, Kenya.
IPCC, 2007.Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, p. 976.
IPCC, 2014.Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, p. 151.
Kabubo-Mariara, J. and F.K. Karanja. 2007. The economic impact of climate change on Kenyan crop agriculture: A Ricardian approach. Global Planet. Change. 57(3): 319-330.
Kendall, M. G., 1975: Rank correlation methods, Charles Griffin, Lomdon. UK.
Knapp, A.K., P. Ciais, M.D. Smith. 2017. Reconciling inconsistencies in precipitation– productivity relationships: implications for climate change. New Phytol. 214(1): 41-47.
Li, X., X. Wang, V. Babovic. 2018. Analysis of variability and trends of precipitation extremes in Singapore during 1980–2013. Int. J. Climatol. 38(1): 125-141.
Liebmann, B., M. P. Hoerling, C. Funk, I. Blade, R. M. Dole, D. Allured, X. Quan, P. Pegion and J. K. Eischeid. 2014. Understanding recent Eastern Horn of Africa rainfall variability and change. J. Cliamate. 27: 8630–8645.
Lobell, D.B., M.B. Burke, C. Tebaldi, M.D. Mastrandrea, W.P. Falcon and R.L. Naylor. 2008. Prioritizing climate change adaptation needs for food security in 2030. Science. 319: 607-610.
Mann, H. B. 1945. Non-parametric test against trend. Econometrica. 13: 245-259.
Mati, B.M. 2000. The influence of climate change on maize production in the semi-humid–semi-arid areas of Kenya. J. Arid Environ. 46(4): 333-344.
Meehl, G. A., T. Karl, D.R. Easterling, S. Changnon, R. PielkeJr, D. Changnon, J. Evans, P.Y. Groisman, T.R. Knutson, K.E. Kunkel, L.O. Mearns, et al. 2000. An introduction to trends in extreme weather and climate events: Observations, socioeconomic impacts, terrestrial ecological impacts, and model projections. Bull. Am. Meteor Soc. 81:413–416.
Milly, P.C.D., K.A. Dunne and A.V. Vecchia. 2005. Global pattern of trends in stream flow and water availability in a changing climate. Nature. 438: 347–350.
Moyo, M., B.M. Mvumi, M. Kunzekweguta, K. Mazvimavi, P. Craufurd and P. Dorward. 2012. Farmer perceptions on climate change and variability in semi-arid Zimbabwe in relation to climatology evidence. J. Afr. Crop Sci. 20: 317- 335.
Mutai, C.C. and M.N. Ward. 2000. East African rainfall and the tropical circulation/convection on intraseasonal to interannual timescales. J. Clim. 13:3915–3939.
Muthoni, J., D.O. Nyamongo and M. Mbiyu. 2017. Climatic change, its likely impact on potato (Solanum tuberosum L.) production in Kenya and plausible coping measures. Int. J. Hort. 7(14): 115-123.
Ngaina, J. and B. Mutai. 2013. Observational evidence of climate change on extreme events over East Africa. Global Meteorol. 2(1): e2.
Ngetich, K.F., M. Mucheru-Muna, J.N. Mugwe, C.A. Shisanya, J. Diels and D.N. Mugendi. 2014. Length of growing season, rainfall temporal distribution, onset and cessation dates in the Kenyan highlands. Agric. Forest Meteorol.188: 24–32.
Niang, I., O.C. Ruppel, M.A. Abdrabo, A. Essel, C. Lennard, J. Padgham, and P. Urquhart. 2014. Africa. In: Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part B: Regional Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Barros, V.R., C.B. Field, D.J. Dokken, M.D. Mastrandrea, K.J. Mach, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, p. 1199-1265.
Nicholson, S.E. 2016. An analysis of recent rainfall conditions in eastern Africa. Int. J. Climatol. 36: 526–532.
Nyakwada, W. 2009. Predictability of East African seasonal rainfall with sea surface temperature gradient modes. PhD Thesis, University of Nairobi, Kenya.
Ochieng, J., L. Kirimi and M. Mathenge. 2016. Effects of climate variability and change on agricultural production: The case of small scale farmers in Kenya. NJAS – Wageningen J. Life Sci. 77: 71-78.
Ogallo, L. 1988. Relationships between seasonal rainfall in East Africa and the Southern Oscillation. J. Climate. 8: 31–43.
Ogallo, L. 1989. The spatial and temporal patterns of the East African seasonal rainfall derived from principal component analysis. Int. J. Climatol. 9:145–167.
Ogallo, L.J., J.E. Janowiak and M.S. Halpert. 1988. Teleconnection between seasonal rainfall over East Africa and global seas surface temperature anomalies. J. Meteorol. Soc. Japan. 66: 807–822.
Ogwang, B.A., H. Chen, G. Tan, V. Ongoma, and D. Ntwali. 2015. Diagnosis of East African climate and the circulation mechanisms associated with extreme wet and dry events: a study based on RegCM4. Arab. J. Geosci. 8: 10255-10265.
Ongoma, V. and H. Chen. 2017. Temporal and spartial variability of temperature and precipitation over East Africa from 1951 to 2010. Meteorol. Atmos. Phys. 129: 131-144.
Ongoma, V., J.N. Muthama, and W. Gitau. 2013. Evaluation of urbanization on urban temperare of Nairobi City, Kenya. Glob. Meteorol. 2:e1.
Ongoma, V., T. Guirong, B.A. Ogwang, and J.P. Ngarukiyimana. 2015. Diagnosis of Seasonal Rainfall Variability over East Africa : A Case Study of 2010-2011 Drought over Kenya. Pakistan J. Meteorol. 11: 13–21
Opiyo, F., M. Nyangito, O.W. Oliver, and P. Omondi. 2014. Trend Analysis of Rainfall and Temperature Variability in Arid Environment of Turkana, Kenya. Environ. Res. J. 8: 30-43.
Owiti, Z., L. A. Ogallo, and J. Mutemi. 2008. Linkages between the Indian Ocean Dipole and east African seasonal rainfall anomalies. J. Kenya Meteorol. Soc. 2(1):3 –17.
Preston, B.L., E.J. Yuen and R.M. Westaway. 2011. Putting vulnerability to climate change on the map: a review of approaches, benefits, and risks. Sustain Sci. 6: 177-202.
Rehmani, M.I.A., G. Wei, N. Hussain, C. Ding, G. Li, Z. Liu, S. Wang and Y. Ding. 2014. Yield and quality responses of two indica rice hybrids to post-anthesis asymmetric day and night open-field warming in lower reaches of Yangtze River delta. Field Crops Res. 156: 231-241.
Sen, P. K.1968. Estimates of the Regression Coefficient Based on Kendall’s Tau. J Amer Stat Assoc 63:1379–1389.
Shisanya, C. A., C. Recha, and A. Anyamba. 2011. Rainfall Variability and Its Impact on Normalized Difference Vegetation Index in Arid and Semi- Arid Lands of Kenya. Int. J. Geosci., 2:36-47.
Siam, M.S., E.A.B. Eltahir. 2017. Climate change enhances interannual variability of the Nile river flow. Nat. Clim. Change. 7: 350.
Silva, V.P.R. 2004. On climate variability in North- East of Brazil, J. Arid Environ. 58: 575-596.
Sun, Q., C. Miao, Q. Duan, H. Ashouri, S. Sorooshian and K.-L. Hsu. 2018. A Review of Global Precipitation Data Sets: Data Sources, Estimation, and Intercomparisons. Rev. Geophys. (Accepted Article). doi: 10.1002/2017RG000574.
Vorosmarty, C.J., P. Green, J. Salisbury and R.B. Lammers. 2000. Global water resources: Vulnerability from climate change and population growth. Science. 289(5477): 284-288.
Wagesho, N., N.K. Goel and M.K. Jain. 2013. Temporal and spatial variability of annual and seasonal rainfall over Ethiopia. Hydrol. Sci. J. 58: 354-373.
Wakachala, F. M., Z. W. Shilenje., J. Nguyo, S. Shaka, and W. Apondo. 2015. Statistical patterns of rainfall variability in the Great Rift Valley of Kenya. J. Environ. Agric. Sci. 5: 17-26.
Xia, J., L. Ning, Q. Wang, J. Chen, L. Wan and S. Hong. 2017. Vulnerability of and risk to water resources in arid and semi-arid regions of West China under a scenario of climate change. Clim. Change. 144(3): 549-563.
Yang, W., R. Seager, M.A. Cane and B. Lyon. 2014. The East African long rains in observations and models. J. Climate. 27: 7185–7202.
Yang, W., R. Seager, M.A. Cane and B. Lyon. 2015. The Annual Cycle of the East African Precipitation. J. Climate 28: 2385 – 2404.
Yue, S., P. Pilon, and G. Cavadias. 2002. Power of the Mann-Kendall and Spearman’s Rho tests for detecting monotonic trends in hydrologic series. J. Hydrol. 259: 254-271.
Zhang, Q., F. Zhang, S. Kang and Z. Cong. 2017. Melting glaciers: Hidden hazards. Science. 356(6337): 495-495.
Zhang, Z. 2018. Climate Modeling. In: Multivariate Time Series Analysis in Climate and Environmental Research. Springer International Publishing, Cham, p. 205-216.
Zuo, D., Z. Xu, D. Peng, J. Song, L. Cheng, S. Wei, K.C. Abbaspour and H. Yang. 2015. Simulating spatiotemporal variability of blue and green water resources availability with uncertainty analysis. Hydrol. Process. 29(8): 1942-1955.
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