DOI: 10.5194/hess-19-4783-2015
Scopus记录号: 2-s2.0-84949267417
论文题名: South Asia river-flow projections and their implications for water resources
作者: Mathison C ; , Wiltshire A ; J ; , Falloon P ; , Challinor A ; J
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2015
卷: 19, 期: 12 起始页码: 4783
结束页码: 4810
语种: 英语
Scopus关键词: Climate models
; Flow of water
; Gages
; Groundwater
; Rivers
; Stream flow
; Asian summer monsoons
; Climate simulation
; Global climate model
; Hydrological process
; Natural variability
; Regional climate modeling (RCM)
; Regional climate projections
; Robust observation
; Water resources
; climate change
; hydrological modeling
; hydrometeorology
; orography
; river flow
; simulation
; water budget
; water management
; water planning
; water resource
; South Asia
英文摘要: South Asia is a region with a large and rising population, a high dependence on water intense industries, such as agriculture and a highly variable climate. In recent years, fears over the changing Asian summer monsoon (ASM) and rapidly retreating glaciers together with increasing demands for water resources have caused concern over the reliability of water resources and the potential impact on intensely irrigated crops in this region. Despite these concerns, there is a lack of climate simulations with a high enough resolution to capture the complex orography, and water resource analysis is limited by a lack of observations of the water cycle for the region. In this paper we present the first 25 km resolution regional climate projections of river flow for the South Asia region. Two global climate models (GCMs), which represent the ASM reasonably well are downscaled (1960-2100) using a regional climate model (RCM). In the absence of robust observations, ERA-Interim reanalysis is also downscaled providing a constrained estimate of the water balance for the region for comparison against the GCMs (1990-2006). The RCM river flow is routed using a river-routing model to allow analysis of present-day and future river flows through comparison with available river gauge observations. We examine how useful these simulations are for understanding potential changes in water resources for the South Asia region. In general the downscaled GCMs capture the seasonality of the river flows but overestimate the maximum river flows compared to the observations probably due to a positive rainfall bias and a lack of abstraction in the model. The simulations suggest an increasing trend in annual mean river flows for some of the river gauges in this analysis, in some cases almost doubling by the end of the century. The future maximum river-flow rates still occur during the ASM period, with a magnitude in some cases, greater than the present-day natural variability. Increases in river flow could mean additional water resources for irrigation, the largest usage of water in this region, but has implications in terms of inundation risk. These projected increases could be more than countered by changes in demand due to depleted groundwater, increases in domestic use or expansion of water intense industries. Including missing hydrological processes in the model would make these projections more robust but could also change the sign of the projections. © 2015 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78370
Appears in Collections: 气候变化事实与影响
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作者单位: Met Office, Hadley Centre, Fitzroy Road, Exeter, United Kingdom; School of Earth and Environment, Institute for Climate and Atmospheric Science, University of Leeds, Leeds, United Kingdom
Recommended Citation:
Mathison C,, Wiltshire A,J,et al. South Asia river-flow projections and their implications for water resources[J]. Hydrology and Earth System Sciences,2015-01-01,19(12)