Skip to main content

Climatology: Seasonal Changes of Rainfall Around Mount Kenya and Its Relation to Atmospheric Circulation

  • 53 Accesses

Part of the International Perspectives in Geography book series (IPG,volume 17)


The regions surrounding Mount Kenya have both long and short rainy seasons, and the corresponding peak rainfalls occur during April and November, respectively. Rainfall in these two seasons reach their maximum potential in areas centered on the southeastern part of the foothills of Mount Kenya and in the Aberdare Range. The relationships between the onset of these rainy seasons and the inland penetrations of the easterly winds at 700 hPa demonstrated that during the long rainy season, wind penetration from the Indian Ocean occurs along the ridge, extending northwards from the southern hemisphere along the eastern coast. During the short rainy season, wind penetration occurs with the strengthening of easterly winds associated with deepening low pressure in the Congo Basin. The relationship between the location of the convergence and divergence of wind field at 700 hPa and the seasonal march of rainfall around Mount Kenya suggest that the seasonal changes in rainfall are not only a result of north–south movement of the convergence zone with the meridional component of wind, but also a result of east–west movement of the divergence zone with the zonal component of wind.


  • Rainy season
  • Dry season
  • Convergence zone
  • Equatorial trough
  • Subtropical ridge
  • Zonal wind

This is a preview of subscription content, access via your institution.

Buying options

USD   29.95
Price excludes VAT (USA)
  • DOI: 10.1007/978-981-16-7853-0_2
  • Chapter length: 15 pages
  • Instant PDF download
  • Readable on all devices
  • Own it forever
  • Exclusive offer for individuals only
  • Tax calculation will be finalised during checkout
USD   109.00
Price excludes VAT (USA)
  • ISBN: 978-981-16-7853-0
  • Instant PDF download
  • Readable on all devices
  • Own it forever
  • Exclusive offer for individuals only
  • Tax calculation will be finalised during checkout
Hardcover Book
USD   149.99
Price excludes VAT (USA)
Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7


  • Camberlin P (1996) Intraseasonal variations of June–September rainfall and upper-air circulation over Kenya. Theor Appl Climatol 115(3–4):107–115

    CrossRef  Google Scholar 

  • Camberlin P, Wairoto J (1997) Intraseasonal wind anomalies related to wet and dry spells during the “long” and “short” rainy seasons in Kenya. Theor Appl Climatol 58(1–2):57–69

    CrossRef  Google Scholar 

  • Funk C, Dettinger MD, Michaelsen JC, Verdin JP, Brown ME, Barlow M, Hoell A (2008) Warming of the Indian Ocean threatens eastern and southern African food security but could be mitigated by agricultural development. Proc Natl Acad Sci USA 105:11081–11086

    CrossRef  Google Scholar 

  • Funk C, Senay G, Aswaw A, Verdin J, Rowland J, Korecha D, Eilerts G, Michaelsen J, Amer S, Choularton R (2005) Recent drought tendencies in Ethiopia and equatorial-subtropical eastern Africa. In: Famine early warning system network special report, US Agency for International Development

    Google Scholar 

  • Funk C, Peterson P, Landsfeld M, Pedreros D, Verdin J, Shukla S, Husak G, Rowland J, Harrison L, Hoell A, Michaelsen J (2015) The climate hazards infrared precipitation with stations—A new environmental record for monitoring extremes. Sci Data 2:150066.

  • Nakamura K (1968) Equatorial westerlies over East Africa and their climatological significance. Geogr Rev Japan 41:359–373

    CrossRef  Google Scholar 

  • Nicholson SE (2017) Climate and climatic variability of rainfall over eastern Africa. Rev Geophys 55:590–635

    CrossRef  Google Scholar 

  • Nicholson SE, Funk C, Fink AH (2018) Rainfall over the African continent from the 19th through the 21st century. Glob Planet Change 165:114–127

    CrossRef  Google Scholar 

  • Oettli P, Camberlin P (2005) Influence of topography on monthly rainfall distribution over East Africa. Clim Res 28:199–212

    CrossRef  Google Scholar 

  • Thompson BW (1966) Mean annual rainfall of Mount Kenya. Weather 21:48–49

    CrossRef  Google Scholar 

  • Williams AP, Funk C (2011) A westward extension of the warm pool leads to a westward extension of the Walker circulation, drying eastern Africa. Clim Dyn 37:2417–2435

    CrossRef  Google Scholar 

  • Yang W, Seager R, Cane MA, Lyon B (2015) The annual cycle of East African precipitation. J Clim 28(6):2385–2404

    CrossRef  Google Scholar 

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Wataru Morishima .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and Permissions

Copyright information

© 2022 The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

About this chapter

Verify currency and authenticity via CrossMark

Cite this chapter

Morishima, W. (2022). Climatology: Seasonal Changes of Rainfall Around Mount Kenya and Its Relation to Atmospheric Circulation. In: Mizuno, K., Otani, Y. (eds) Glaciers, Nature, Water, and Local Community in Mount Kenya. International Perspectives in Geography, vol 17. Springer, Singapore.

Download citation