Assessing impacts of climate change on hydrology in data-scarce Volta River Basin using downscaled reanalysis data

摘要

This study uses high resolution (0.3°~3 km) climate forecast system reanalysis (CFSR), SWAT and statistically downscaled A1B emission scenario to assess impacts of climate change on hydrology in data scarce Volta River Basin of West Africa. SWAT was calibrated to simulate runoff at six gauging stations within the basin. Using 1979-2008 as baseline, there is average increase in rainfall of 3.0% to 5.0%. Average rainfall in 2071-2100 is higher than 2041-2070 and 2011-2040 by 0.9% and 2.0%, respectively. Monthly runoff is projected to increase from February to August and decrease from September to January. Overall, the simulation reveals increased variability and increase of 12.0% in average annual runoff. The results give more insight into future water availability and provide quantitative data for incorporation into climate change adaptation policies for effective water resources management in the basin.