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Evaporation values in East Africa

Werte der Verdunstung in Ost-Afrika

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Summary

Potential evaporation (E p) and actual evapotranspiration (E A) values for 84 East African stations were estimated and mapped using Morton [12, 13, 14] model. The data used in the study were long term averages up to and including 1974. TheE p andE A distributions for the months of January, April, and July and October; and annual are discussed. HighE p values exist in the semi-arid/arid areas of northern and northeastern Kenya and central Tanzania. LowE p values dominate on the highland areas. HighE A values are observed over the East African rainfall favoured and thickly vegetated areas whereas the lowestE A values are predominantly observed during all months in semi-arid/arid areas. BothE p andE p values show a good agreement with the north/south movement of the rain belts across East Africa.

Zusammenfassung

Es werden für 84 Stationen in Ost-Afrika nach der Methode von Morton [12, 13, 14] die Werte der potentiellen VerdunstungE p und der aktuellen EvapotranspirationE A bestimmt und ihre Verteilungen in Kartendarstellungen wiedergegeben. Als Beobachtungsdaten wurden langzeitige Mittelwerte bis einschließlich 1974 verwendet. Die Verteilung vonE p undE A wird für die Monate Januar, April, Juli, Oktober und für das Jahr besprochen. HoheE p -Werte kommen in den semiariden und ariden Gebieten von Nord- und Nordost-Kenya und von Zentral-Tanzania vor. NiedrigeE p-Werte sind in Hochlandgebieten vorherrschend. HoheE A -Werte werden in Ost-Afrika in den von Regen begünstigten und dicht mit Vegetation bewachsenen Gebieten beobachtet, während die niedrigstenE A-Werte vorwiegend in allen Monaten in semiariden und ariden Gebieten festgestellt werden. DieE p- undE A -Werte zeigen eine gute Übereinstimmung mit der Nord-Süd-Verlagerung der Regengürtel über Ost-Afrika.

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Authors and Affiliations

  1. Meteorological Department and Department of Meteorology, University of Nairobi, P.O. Box 30197, Nairobi, Kenya, East Africa

    B. S. Nyenzi,  P. M. R. Kiangi & N. N. P. Rao

Authors
  1. B. S. Nyenzi
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  2. P. M. R. Kiangi
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  3. N. N. P. Rao
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Nyenzi, B.S., Kiangi, P.M.R. & Rao, N.N.P. Evaporation values in East Africa. Arch. Met. Geoph. Biocl., Ser. B 29, 37–55 (1981). https://doi.org/10.1007/BF02278189

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  • DOI: https://doi.org/10.1007/BF02278189

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