Analysis of rainfall trend in Ethiopia

Seifu Admassu; Dr. Ing.Abdulkarim H.Seid

Seifu Admassu Bahir Dar University, Faculty of Engineering, Department of Water Resource Engineering
Dr. Ing.Abdulkarim H.Seid Nile Basin Initiative, Water Resources Planning and Management Project

Keywords: Trend, Mann Kendall, Kiremt, Belg, Annual

Abstract

Agricultural production in Ethiopia is predominantly rain fed. Variation of rainfa ll in space and time affects the agricultural production system in the country. This needs a close study on rainfall variation. Rainfall variation, called trend, has been assessed for total annual, Kiremt (June-September) and Belg (February-May) rainfall, using I 0 selected stations over the period of 1973-2002 in Ethiopia. Trend-free Pre-whitening Mann-Kendall statistical test at the stations show that Belg rainfall totals do not show significant trend while Kiremt rainfall totals on Gore (-7. 75mm/year) and J ijiga (-5.87mm/year), Sep-Nov total rainfall on N.Borena (-.,J.25mm/year) and annual rainfall totals on Gore (-I 2.2mm/year) and N.Borena {-11.11 mm/year) show significant decreasing trend during the period. It is recommended to extend the study on more number of stations to conclude at regional level.