Temporal Hydrologic Alterations Coupled with Climate Variability and Drought for Transboundary River Basins

Abstract

Climate change (CC) and drought episode impacts linked with anthropogenic pressure have become an increasing concern for policy makers and water resources managers. The current research presents a comprehensive methodology but simple approach for predicting the annual streamflow alteration based on drought indices and hydrological alteration indicators. This has been achieved depending on the evaluation of drought severity and CC impacts during the human intervention periods to separate the influence of climatic abnormality and measure the hydrologic deviations as a result of streamflow regulation configurations. As a representative case study, the Lesser Zab River Basin in northern Iraq has been chosen. In order to analyse the natural flow regime, 34 hydrological years of streamflow prior to the main dam construction were assessed. The Indicators of Hydrologic Alteration (IHA) method has been applied to quantify the hydrological alterations of various flow characteristics. In addition, an easy approach for hydrological drought prediction in relatively small basins grounded on meteorological parameters during the early months of the hydrological year has been presented. The prediction was accomplished by implementing the one-dimensional drought examination and the reconnaissance drought index (RDI) for evaluating the severity of meteorological drought. The proposed methodology is founded on linear regression relations connecting the RDI of 3, 6, and 12 months and the streamflow drought index (SDI). The results are critical for circumstances where an early exploration of meteorological drought is obtainable. Outcomes assist water resources Water Resour Manage

Climate change and anthropogenic intervention impact on the hydrologic anomalies in a semi-arid area: Lower Zab River Basin, Iraq

“…Droughts on a cyclical base were identified for 5 years over the considered dataset; mostly for 1998 /1999, 1999/2000, 2000/2001, 2007/2008, and 2008/2009 (for example, corresponding RDI st mean values were − 1.76, − 1.39, − 1.60, − 2.68, and − 1.70 in this order). Similar findings were reported, previously (Fadhil 2011;UNESCO 2014;Mohammed et al 2017). In general, droughts typically occur at the start of the rainy period, which is reflected by either a decrease in precipitation coupled with a potential evapotranspiration increase or a postponement in precipitation incidents.…”

“…The Little Zab River crosses varied climatic and ecological zones. The minimum, average and maximum discharges of this river are 6, 227 and 3420 m 3 /s in this order (Mohammed et al 2017). Annual precipitation near the river declines from > 1000 mm (Iranian Zagros) to < 200 mm (confluence with the Tigris River).…”

“…The average yearly storage of the river at Dokan and Altun Kupri-Goma is roughly 7.0 billion cubic metres (BCM) and 7.8 BCM, respectively (Mohammed et al 2017); refer also to Fig. 1.…”

“…Developments in upstream and downstream areas commonly vary, indicating different uncertainties in climate change impacts on the future availability of water. Mohammed et al (2017) reported on severe drought impacting on the basin during the hydrologic year 2007/2008 due to about 80% reduction in the sub-basin average precipitation (P av ). Therefore, the restricted water access reduced the living standard of the population and agricultural crop production.…”

Review on Water Resources Management and Key Threats in Rwanda, East Africa

“…The total population of Kigali, the capital city of Rwanda, gradually grew from 357 in 1907 to 236,000 inhabitants in 1991 and reached 1,000,000 and 1.132 million in 2010 and 2012 respectively (National…, 2014). This however, affects the municipal wastes management due to informal settlements, expansion of the city and industrialization whose final results is water quality degradation and pollution as well (Mohammed et al, 2017;Uwimbabazi, Lawrence, 2011). Despite the present Governmental initiative (which is not yet fully completed) of re-allocating industries from or near watersheds to appropriate and well equipped location (Rwanda Special Economic Zone), their former location led to immense wetland and biodiversity degradation (Etale, Drake, 2013;Nhapi et al, 2011).…”