Advertisement

GeoJournal

, Volume 3, Issue 2, pp 193–200 | Cite as

The East African monsoons and their effects on agriculture

  • Nieuwolt S. Nairobi
Article

Abstract

Though the East African monsoons may be considered as mere extensions of the South Asian monsoonal system, they possess a number of characteristics which make them unique amongst the world's monsoons. The most important of these is the relative dryness of both the North and the South monsoon, caused by a prevalent low-level divergence over eastern Africa. Most rainfall in the region therefore occurs during the intermediate seasons between the monsoons, when this divergence is temporarily replaced by more convergent flow patterns. As a result, total rainfall in East Africa is relatively low. Over most of the region it is strongly concentrated during two short seasons and it is highly variable from year to year, both in total amount and in time of occurrence.

As in most parts of the tropics, rainfall is the main limiting factor in agricultural production in East Africa. The relations between rainfall and agriculture can be illustrated by the usual water balances, but an alternative method, employing the Agricultural Rainfall Indicator, is more useful for planning purposes. Drought frequencies, based on a simple relation between actual and average rainfall, also represent the effects of the monsoons on East African agriculture very clearly.

Keywords

Environmental Management Flow Pattern Agricultural Production Water Balance Simple Relation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. East African Meteorological Department: Monthly and annual rainfall in Uganda, Kenya and Tanganyika and Zanzibar for the period 1931–1960. 33, 172 and 105 pages (1965, 1966)Google Scholar
  2. East African Meteorological Department: Mean annual Rainfall Map of East Africa. 2 sheets, 1971.Google Scholar
  3. East Africa Royal Commission: Report for 1953–1955. London, pp. 252–254 and Map 3, 1961.Google Scholar
  4. Flohn, H.: Über die Ursachen der Aridität Nordost-Afrikas. Würzburger Geogr. Arb., 12, 25–41 (1964)Google Scholar
  5. Glantz, M.H. and Katz, R.W.: When is a drought a drought? Nature. 267 (5608), 192–193 (1977)Google Scholar
  6. GRIFFITHS, J.F.: The Climate of East Africa. In: East Africa, its people and resources. Morgan, W.T.W., ed., pp. 110–113, 1969.Google Scholar
  7. Johnson, D.H.: Rain in East Africa. Quarterly Journal of the Royal Met. Society. 88, 1–19 (1962)Google Scholar
  8. NIEUWOLT, S.: Rainfall and Evaporation in Tanzania. BRALUP Research Paper Nr. 24, Dar es Salaam, p. 7 (1973)Google Scholar
  9. Nieuwolt, S.: Seasonal rainfall distribution in Tanzania and its cartographic representation. Erdkunde, 28, 186–194 (1974)Google Scholar
  10. Nieuwolt, S.: Rainfall variability and drought frequencies in East Africa. Erdkunde, 32, 81–88 (1978)Google Scholar
  11. OBASI, G.O.P. and KIANGI, P.M.R.: Water Balance in Kenya. p. 3, 4, 1973.Google Scholar
  12. RAMAGE, C.S.: Monsoon Meteorology. pp. 3–6, New York, 1971.Google Scholar
  13. Thornthwaite, C.W.: An approach toward a rational classification of climate. Geogr. Review, 38, 55–94 (1948)Google Scholar
  14. Thornthwaite, C.W. and Mather, J.R.: Instructions and Tables for Computing Potential Evapotranspiration and the Water Balance. pp. 243–311, Centerton, N.J., 1957.Google Scholar
  15. Woodhead, T.: The Water Balance as a guide to site potential. Journal of Applied Ecology, 7, 647–652 (1970)Google Scholar

Copyright information

© Akademische Verlagsgesellschaft 1979

Authors and Affiliations

  • Nieuwolt S. Nairobi
    • 1
  1. 1.Dept. of Geogr.Kenyatta University CollegeNairobiKenya

Personalised recommendations