Process Based Understanding of Drought in the Upper Blue Nile Basin, Process Based Understanding of Drought in the Upper Blue Nile Basin, Ethiopia
| dc.contributor.advisor | Dereje, Hailu (PhD) | |
| dc.contributor.author | Endalew, Ashagrie | |
| dc.date.accessioned | 2019-01-17T07:27:35Z | |
| dc.date.accessioned | 2023-11-11T08:32:18Z | |
| dc.date.available | 2019-01-17T07:27:35Z | |
| dc.date.available | 2023-11-11T08:32:18Z | |
| dc.date.issued | 2016-12 | |
| dc.description.abstract | Drought poses immense impacts on economic activities, human lives and the environment. The main objective of this study is to characterize the drought condition of the (UBNB) by applying Standardized Precipitation Index (SPI) and Soil Moisture Deficit Index (SMDI). Drought indices have been derived from actual precipitation, ECMWF precipitation and soil moisture product and simulated using MATLAB 2015a. Comparison of datasets shows ECMWF precipitation product underestimate 45% the whole data and 20% of the data was overestimated from actual precipitation. SPI showed too much fluctuation between drought and normal conditions at shorter time scales (SPI-3 and SPI-6) and there are an increasing in the duration and magnitude of drought with timescale. SPI using ECMWF product exhibit low results in terms of coefficient of determination (R 2 ) and more than 50% of percentage deviations were under scanty range compared with SPI using actual precipitation product. SPI shows ECMWF product has lower tendency to capturing severe drought events. However, the chronic drought events i.e.1984/85, 1995/96, 2003/04 and 2009/10 have been characterized and captured well by SMDI and events were occurred less frequently with longer duration. Hence, SMDI shows a good correspondence with extent of historical drought events and better to capture drought events than the SPI and ECMWF product needs further correction before implement the data for drought analysis. The drought event during years 1984/85 was the most critical drought years in the basin with more than 57% of the total basin area under extreme drought and more than 32% of the total basin area under severe drought. So, it recommended to conduct further bias correction for all rainfall season and to evaluate other ECMWF product like temperature for its effectiveness. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/12345678/15841 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Drought | en_US |
| dc.subject | Drought index | en_US |
| dc.subject | ECMWF | en_US |
| dc.subject | Grid | en_US |
| dc.subject | Upper Blue Nile Basin | en_US |
| dc.title | Process Based Understanding of Drought in the Upper Blue Nile Basin, Process Based Understanding of Drought in the Upper Blue Nile Basin, Ethiopia | en_US |
| dc.type | Thesis | en_US |