DOI: 10.5194/hess-22-5527-2018
论文题名: Modelling the water balance of Lake Victoria (East Africa)-Part 2: Future projections
作者: Vanderkelen I. ; Van Lipzig N.P.M. ; Thiery W.
刊名: Hydrology and Earth System Sciences
ISSN: 1027-5606
出版年: 2018
卷: 22, 期: 10 起始页码: 5527
结束页码: 5549
语种: 英语
Scopus关键词: Climate change
; Climate models
; Dams
; Evaporation
; Hydroelectric power
; Hydroelectric power plants
; Sustainable development
; Uncertainty analysis
; Water levels
; Electricity generation
; Environmental conservation
; Hydro-power generation
; Lake level fluctuations
; Main controlling factors
; Regional climate models
; Sustainable management
; Water balance models
; Lakes
; downscaling
; evaporation
; future prospect
; lake level
; lake water
; outflow
; regional climate
; sustainability
; water availability
; water budget
; East African Lakes
; Lake Victoria
; Nile [Uganda]
; Uganda
英文摘要: Lake Victoria, the second largest freshwater lake in the world, is one of the major sources of the Nile river. The outlet to the Nile is controlled by two hydropower dams of which the allowed discharge is dictated by the Agreed Curve, an equation relating outflow to lake level. Some regional climate models project a decrease in precipitation and an increase in evaporation over Lake Victoria, with potential important implications for its water balance and resulting level. Yet, little is known about the potential consequences of climate change for the water balance of Lake Victoria. In this second part of a two-paper series, we feed a new water balance model for Lake Victoria presented in the first part with climate simulations available through the COordinated Regional Climate Downscaling Experiment (CORDEX) Africa framework. Our results reveal that most regional climate models are not capable of giving a realistic representation of the water balance of Lake Victoria and therefore require bias correction. For two emission scenarios (RCPs 4.5 and 8.5), the decrease in precipitation over the lake and an increase in evaporation are compensated by an increase in basin precipitation leading to more inflow. The future lake level projections show that the dam management scenario and not the emission scenario is the main controlling factor of the future water level evolution. Moreover, inter-model uncertainties are larger than emission scenario uncertainties. The comparison of four idealized future management scenarios pursuing certain policy objectives (electricity generation, navigation reliability and environmental conservation) uncovers that the only sustainable management scenario is mimicking natural lake level fluctuations by regulating outflow according to the Agreed Curve. The associated outflow encompasses, however, ranges from 14m3 day-1 (-85 %) to 200m3 day-1 (C100 %) within this ensemble, highlighting that future hydropower generation and downstream water availability may strongly change in the next decades even if dam management adheres to he Agreed Curve. Our results overall underline that managing the dam according to the Agreed Curve is a key prerequisite for sustainable future lake levels, but that under this management scenario, climate change might potentially induce profound changes in lake level and outflow volume. © 2018 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/163158
Appears in Collections: 气候变化与战略
There are no files associated with this item.
作者单位: Vanderkelen, I., Department of Hydrology and Hydraulic Engineering, Vrije Universiteit Brussel, Brussels, Belgium; Van Lipzig, N.P.M., Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium; Thiery, W., Department of Hydrology and Hydraulic Engineering, Vrije Universiteit Brussel, Brussels, Belgium, Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland
Recommended Citation:
Vanderkelen I.,Van Lipzig N.P.M.,Thiery W.. Modelling the water balance of Lake Victoria (East Africa)-Part 2: Future projections[J]. Hydrology and Earth System Sciences,2018-01-01,22(10)