Summary
The interannual variability of seasonal Bhalme-and-Mooley-type drought indices over the savanna belt of Nigeria is examined and a 57-year (1931–1987) drought area series has been derived using 34 stations. The area under drought conditions is obtained by considering areas which have drought indices of less than — 1.0. The interannual variability of the drought areas is large, demonstrating large variations in the seasonal rainfall over the region. Statistical tests suggest a significant long-term increasing trend in the areal extent of drought. In particular, there is a major shift towards an increase in the mean areal extent of drought between the two periods 1931–1960 and 1961–1987.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Bhalme, H. N., Mooley, D. A., 1980: Large-scale droughts/floods and monsoon circulation.Mon. Wea. Rev. 108, 1197–1211.
Charney, J. G., 1975: Dynamics of deserts and drought in the Sahel.Quart. J. Roy. Meteor. Soc. 101, 193–202.
Elthair, E. A. B., 1989: A feedback mechanism in annual rainfall, central Sudan.J. Hydrol. 110, 323–334.
Farago, T., Kozma, E., Nemes, Cs., 1988: Quantifying droughts. In: Antal, E., Glantz, M. H. (eds.)Identifying and Coping with Extreme Meteorological Events. Budapest: Hungarian Meteorological Service, pp. 62–110.
Gilman, D. L. et al., 1963: On power spectrum of “red noise”.J. Atmos. Sci. 20, 182–184.
Hounam, C. E. et al., 1975:Drought and Agriculture. Geneva: WMO Tech. Note 138, 127 pp.
Hulme, M., Kelly, P. M., 1992:Climate Change, Desertification and Dessication with Particular Emphasis in the African Sahel. A briefing paper prepared for the Overseas Development Administration. Climate Research Unit, Norwich, 23 pp. (unpublished).
Khalil, T. M., 1974:Nort-Eastern State Report on Long-Term Strategies to Combat Drought. Maiduguri, Nigeria: Ministry of Natural Resources, 53 pp.
Mitchell, J. M. et al., 1966:Climate Change. Geneva: WMO Tech. Note 79, 79 pp.
Oguntoyinbo, J. S., Richards, P., 1977: The extent and intensity of the 1969–1973 drought in Nigeria: A provisional analysis. In: Dalby, D., et al. (eds.)Drought in Africa 2. African Environment Special Report 6. London: U.K., pp. 114–126.
Oladipo, E. O., 1985: A comparative performance analysis of three meteorological drought indices.J. Climatol. 5, 655–664.
Owen, D. B., 1962:Handbook of Statistical Tables. New York: Addison-Wesley, 580 pp.
Shuaibu, U., Oladipo, E. O., 1993: A Bhalme-Mooley-type meteorological drought intensity index for northern Nigeria.Zaria Geographer, (in press).
Swed, F. S. Eisenhart, C., 1943: Tables for testing randomness of grouping in a sequence of alternation.Ann. Math. Stat. 14, 66–87.
Author information
Authors and Affiliations
Additional information
With 4 Figures
Rights and permissions
About this article
Cite this article
Oladipo, E.O. Some statistical characteristics of drought area variations in the savanna region of Nigeria. Theor Appl Climatol 50, 147–155 (1995). https://doi.org/10.1007/BF00866113
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00866113