Dept. of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, Canada.
Dept. of Civil Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada.
Sci Total Environ. 2021 May 1;767:144863. doi: 10.1016/j.scitotenv.2020.144863. Epub 2021 Jan 2.
The water resource of the Blue Nile River basin (BNRB) has been under pressure due to growing demands from many users, and the climate change impact. Potential impact of climate change for the maximum, median and minimum projected changes in the simulated streamflow of BNRB by a hydrologic model, VIC, driven by Representative Concentration Pathways climate scenarios, RCP4.5 and RCP8.5, of 4 GCMs (global climate models) downscaled dynamically by a regional climate model, WRF (Weather Research Forecasting) using a one-domain framework that covers the entire NRB for 2041-2070 and 2071-2100. These projected changes in streamflow were used to assess its future water allocations using a stochastic Dual Dynamic Programming (SDDP) algorithm and a hydro-economic model to optimize hydropower production and irrigated agriculture. Overall, it seems the Grand Ethiopian Renaissance Dam (GERD) reservoir will likely not operate at full storage level because the streamflow of BNRB is assumed to be regulated by three upstream reservoirs. The outflow from the reservoir of GERD or BNRB's annual flow at Khartoum is projected to increase under maximum, but is expected to decrease under minimum and median projected changes in streamflow for 2041-2070 and 2071-2100, respectively. Given the annual net benefit obtained from hydropower production and irrigated agriculture of the reservoir is projected to increase (decrease) under the maximum (median and minimum) projected changes in streamflow, the potential climate change impact should be considered in designing and developing the future water resources of BNRB.
青尼罗河河流域（BNRB）的水资源一直承受着来自众多用户不断增长的需求以及气候变化的压力。为了评估气候变化对模拟流量的潜在影响，采用了水文模型 VIC，由 4 个全球气候模型（GCMs）驱动，使用气象研究与预报模型（WRF）进行动力降尺度，覆盖了整个 NRB。WRF 采用了一个包含整个 NRB 的单区域框架，代表浓度路径气候情景（RCP4.5 和 RCP8.5）模拟了 BNRB 的最大、中位数和最小预计变化。这些预测的流量变化将用于使用随机双动态规划（SDDP）算法和水-经济模型评估未来的水资源分配，以优化水电生产和灌溉农业。总体而言，GERD 水库似乎不太可能满负荷运行，因为 BNRB 的流量被假定由三个上游水库调节。根据预测，在 2041-2070 年和 2071-2100 年期间，最大流量下 GERD 水库或 BNRB 的年流量流出量预计会增加，但在最大、中位数和最小流量预测变化下预计会减少。鉴于从水库获得的水电生产和灌溉农业的年度净效益预计会随着流量的最大（中位数和最小）预测变化而增加（减少），因此在设计和开发 BNRB 的未来水资源时，应考虑潜在的气候变化影响。
