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161.
162.
基于气候变化的干旱脆弱性评价——以青海东部为例 总被引:1,自引:0,他引:1
基于青海东部农业区22个县区的20个气象、农业、社会经济统计指标,利用层次分析法和等级化等数学分析方法,分别进行了暴露性、敏感性和适应性的评价,再通过分析承险体的内在脆弱性,将气候变化和内在脆弱性进行综合分析,得到了青海东部干旱脆弱性等级。结果表明:在目前全球变暖背景下,干旱脆弱性最高的是民和、化隆,较高的是城中、城北区、湟中、大通等四县区,门源、互助、同仁、同德的干旱脆弱性中等。在此基础上,提出了强化旱灾的风险管理模式、倡导节约型水资源开发利用模式等干旱防范措施。 相似文献
163.
气候变化对鄱阳湖流域干旱灾害影响及其对策 总被引:6,自引:0,他引:6
以我国历史气候变化的事实与过程重建的成果为基础,以历史文献为依据,分析了两宋以来鄱阳湖流域气候变化与洪水干旱灾害发生的关系,结果表明,不管气候处于温湿期还是冷干期,发生洪水灾害的频率没有显著区别;但是当气候处于冷干时期,发生干旱灾害的频率增大,特大干旱年和连续干旱年组频频出现。利用气象、水文资料统计分析表明,最近60 a来,气温呈现增高趋势,逐年的日降水强度明显增加,洪水干旱等极端事件发生更加频繁。为了更好地应对干旱灾害,必须加强水需求管理、坚持节约用水为先;加强病险水库的治理,使其充分发挥作用;对现有水利工程进行再评估,实施适应性管理,充分挖掘工程潜力;加大力度,新建与自然和谐相处的水利工程 相似文献
164.
Pete Campana John Knox Andrew Grundstein John Dowd 《Journal of the American Water Resources Association》2012,48(2):379-390
Campana, Pete, John Knox, Andrew Grundstein, and John Dowd, 2012. The 2007‐2009 Drought in Athens, Georgia, United States: A Climatological Analysis and an Assessment of Future Water Availability. Journal of the American Water Resources Association (JAWRA) 48(2): 379‐390. DOI: 10.1111/j.1752‐1688.2011.00619.x Abstract: Population growth and development in many regions of the world increase the demand for water and vulnerability to water shortages. Our research provides a case study of how population growth can augment the severity of a drought. During 2007‐2009, a drought event that caused extreme societal impacts occurred in the Athens, Georgia region (defined as Clarke, Barrow, Oconee, and Jackson counties). An examination of drought indices and precipitation records indicates that conditions were severe, but not worse than during the 1925‐1927, 1954‐1956, and 1985‐1987 drought events. A drought of similar length to the 2007‐2009 drought would be expected to occur approximately every 25 years. Streamflow analysis shows that discharge levels in area streams were at a record low during 2007 before water restrictions were implemented, because of greater water usage caused by recent population increases. These population increases, combined with a lack of water conservation, led to severe water shortages in the Athens region during late 2007. Only after per capita usage decreased did water resources last despite continuing drought conditions through 2009. Retaining mitigation strategies and withdrawal levels such as seen during the height of the drought will be an essential strategy to prevent water shortages during future extreme drought events. The key mitigation strategy, independent local action to restrict water use in advance of state‐level restrictions, is now prohibited by Georgia State Law. 相似文献
165.
Unusual Salinity Conditions in the Yangtze Estuary in 2006: Impacts of an Extreme Drought or of the Three Gorges Dam? 总被引:1,自引:0,他引:1
During the extreme dry year of 2006, abnormal salinity conditions in the Changjiang Estuary of the Yangtze River occurred
in partial coincidence with the second impoundment phase of the TGD (Three Gorges Dam). Analysis of discharge observations
in the upper reaches of the estuary and of salinity observations in the estuary as a whole reveals that in 2006 salinity was
over 100 mg/l during 275 days, over 250 mg/l during 75 days and over 400 mg/l during 48 days. It is well known that this is
due to extreme low discharges from the upper catchment area into the estuary. Moreover, large amounts of water consumed along
the lower reaches of the Yangtze River can also aggravate the low discharges that lead to stronger saltwater intrusion in
the estuary. Of the 75 days that salinity was over 250 mg/l, the low discharge was decreased further by 10 to 20% due to water
consumption. The additional impact of the impoundment phase of the TGD (lasting 37 days in autumn) was noticeable only during
7 days in 2006. During that period, the relative contributions of the TGD and the water consumption in the lower reaches of
the Yangtze River amounted to 70 and 30%, respectively. It may be concluded that the impact of the second impoundment phase
of the TGD on salinity intrusion in the estuary was modest, while the extreme drought of 2006 was the dominant cause. 相似文献
166.
Gavin Gong Lucien Wang Laura Condon Alastair Shearman Upmanu Lall 《Journal of the American Water Resources Association》2010,46(3):574-585
Gong, Gavin, Lucien Wang, Laura Condon, Alastair Shearman, and Upmanu Lall, 2010. A Simple Framework for Incorporating Seasonal Streamflow Forecasts Into Existing Water Resource Management Practices. Journal of the American Water Resources Association (JAWRA) 46(3):574-585. DOI: 10.1111/j.1752-1688.2010.00435.x Abstract: Climate-based streamflow forecasting, coupled with an adaptive reservoir operation policy, can potentially improve decisions by water suppliers and watershed stakeholders. However, water suppliers are often wary of straying too far from their current management practices, and prefer forecasts that can be incorporated into existing system modeling tools. This paper presents a simple framework for utilizing streamflow forecasts that works within an existing management structure. Climate predictors are used to develop seasonal inflow forecasts. These are used to specify operating rules that connect to the probability of future (end of season) reservoir states, rather than to the current storage, as is done now. By considering both current storage and anticipated inflow, the likelihood of meeting management goals can be improved. The upper Delaware River Basin in the northeastern United States is used to demonstrate the basic idea. Physically plausible climate-based forecasts of March-April reservoir inflow are developed. Existing simulation tools and rule curves for the system are used to convert the inflow forecasts to reservoir level forecasts. Operating policies are revised during the forecast period to release less water during forecasts of low reservoir level. Hindcast simulations demonstrate reductions of 1.6% in the number of drought emergency days, which is a key performance measure. Forecasts with different levels of skill are examined to explore their utility. 相似文献
167.
168.
169.
Douglas S. Kenney Christopher Goemans Roberta Klein Jessica Lowrey Kevin Reidy 《Journal of the American Water Resources Association》2008,44(1):192-207
Abstract: Residential water demand is a function of several factors, some of which are within the control of water utilities (e.g., price, water restrictions, rebate programs) and some of which are not (e.g., climate and weather, demographic characteristics). In this study of Aurora, Colorado, factors influencing residential water demand are reviewed during a turbulent drought period (2000‐2005). Findings expand the understanding of residential demand in at least three salient ways: first, by documenting that pricing and outdoor water restriction policies interact with each other ensuring that total water savings are not additive of each program operating independently; second, by showing that the effectiveness of pricing and restrictions policies varies among different classes of customers (i.e., low, middle, and high volume water users) and between predrought and drought periods; and third, in demonstrating that real‐time information about consumptive use (via the Water Smart Reader) helps customers reach water‐use targets. 相似文献
170.
西北干旱灾害影响因子分析 总被引:11,自引:3,他引:8
干旱是西北地区最严重的灾害,利用西北地区降水和农作物旱灾面积统计资料,将干旱灾害事件与影响因子进行对比分析,结果表明:厄尔尼诺事件当年或次年,南方涛动指数负距平,太阳黑子低值,青藏高原为多雪年,地表径流枯期,西北干旱灾害发生率较高。 相似文献