Research Article
Trend and Variability in Flood Discharge and Attribution to Climate Change in Wabi Shebele River Basin, Ethiopia
@INPROCEEDINGS{10.1007/978-3-030-80618-7_7, author={Fraol Abebe Wudineh and Semu Ayalew Moges and Belete Berhanu Kidanewold}, title={Trend and Variability in Flood Discharge and Attribution to Climate Change in Wabi Shebele River Basin, Ethiopia}, proceedings={Advances of Science and Technology. 8th EAI International Conference, ICAST 2020, Bahir Dar, Ethiopia, October 2-4, 2020, Proceedings, Part II}, proceedings_a={ICAST PART 2}, year={2021}, month={7}, keywords={Peak over threshold Temporal variability Quantile Perturbation Method (QPM)}, doi={10.1007/978-3-030-80618-7_7} }- Fraol Abebe Wudineh
Semu Ayalew Moges
Belete Berhanu Kidanewold
Year: 2021
Trend and Variability in Flood Discharge and Attribution to Climate Change in Wabi Shebele River Basin, Ethiopia
ICAST PART 2
Springer
DOI: 10.1007/978-3-030-80618-7_7
Abstract
This study tried to investigate trends and variabilities in mean and extreme hydro-climatic variables in Wabi Shebele River Basin using data based statistical approach. Linear trend investigation and Mann-kendall trend significance tests are performed as a preliminary analysis to see trends on mean discharges and climate variables, while Quantile Perturbation Method (QPM) analysis is conducted to detect clear oscillating patterns and trends in extremes. The result indicates that less increasing trend in mean annual discharge in the basin up to 0.58 Mm3/year, 1.49 Mm3/year, 0.94 Mm3/year and 11.06 Mm3/year in Maribo, Wabi at Dodola, Robe and Erer river respectively. Similarly, less increasing trend is observed in annual rainfall in western and eastern upper basin whereas decreasing trend in middle and lower part of the basin. Mean temperature shows significant increasing trend in upper and middle part of the basin, but decreasing trend in lower basin. The QPM analysis in flood and precipitation extremes indicates there is five/5/ year frequency of significant anomalies and general increasing trends in floods. In early 1980s, significant negative perturbation was observed in Maribo, Robe and Erer rivers. The precipitation extreme anomalies increase at Adaba station and decrease at Robe (Arsi) station. The correlation between discharges and precipitation decreases from West upper to lower basin part of the basin. Average correlation value (R2) of 0.23%, 0.027%, 0.02% and 0.08% are observed in Maribo, Robe, Tebel and Erer watersheds respectively.
