ABSTRACT
The Upper Tekeze river basin–part of the Nile basin, is characterized by high temporal and spatial variability of rainfall and streamflow. This chapter investigates the spatiotemporal variability of rainfall and streamflow in the headwaters of Tekeze basin and identifies any abrupt changes if significant trends exist. It explores the impact of climate change reflected in change in rainfall patterns on the hydrological variability of the basin. Spatio-temporal datasets of rainfall and streamflow are required for the trend and change point analyses. These statistical analyses directly depend on the quality and length of the time series data. Streamflow data from all gauging stations in the basin were obtained from the Ethiopian Ministry of Water Resources and Energy. A longer period of historical data increases the visibility of dominant trends and the reliability of results from trend analyses, while a shorter period enhances spatial coverage of streamflow by including more representing stations at different parts of the basin.
