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排序方式: 共有568条查询结果,搜索用时 31 毫秒
471.
安徽省水旱灾害与社会经济可持续发展 总被引:3,自引:2,他引:1
分析了安徽省水旱灾害及其成因与特点,阐述了防洪减灾事业的可持续发展。防汛抗旱是基础性、公益性事业,应当优先发展,重点建设,要全面规划,标本兼治,综合治理;要开源节流,挖潜改造,实现水资源可持续利用,要强化防汛抗旱的非工程措施;要努力提高防汛抗灾的科技含量。 相似文献
472.
LIU Chuanfeng 《中国减灾(英文版)》2001,(4)
1 Climate background Although the La Nina event caused the decrease of the mean temperature in the tropical regions of the Pacific Ocean, the year 2000 had remained one of the hottest since 1860 when records of the global mean temperature began. The temperature in the areas to the north of 20扤 from December 1999 to November 2000 marked the second warmest in history. The mean temperature of the global surface in 2000 was 0. 60C above the average during the period 1880?999, and was close to … 相似文献
473.
Yongjun Zhang Xiaomao Lin Prasanna Gowda David Brown Zachary Zambreski Seth Kutikoff 《Journal of the American Water Resources Association》2019,55(6):1370-1381
Recent severe drought events have occurred over the Ogallala Aquifer region (OAR) during the period 2011–2015, creating significant impacts on water resources and their use in regional environmental and economic systems. The changes in terrestrial water storage (TWS), as indicated by the Gravity Recovery and Climate Experiment (GRACE), reveals a detailed picture of the temporal and spatial evolution of drought events. The observations by GRACE indicate the worst drought conditions occurred in September 2012, with an average TWS deficit of ~8 cm in the northern OAR and ~11 cm in the southern OAR, consistent with precipitation data from the Global Precipitation Climatology Project. Comparing changes in TWS with precipitation shows the TWS changes can be predominantly attributable to variations in precipitation. Power spectrum and squared wavelet coherence analysis indicate a significant correlation between TWS change and the El Nino‐Southern Oscillation, and the influence of equatorial Pacific sea surface temperatures on TWS change is much stronger in the southern OAR than the northern OAR. The results of this study illustrate the value of GRACE in not just the diagnosis of significant drought events, but also in possibly improving the predictive power of remote signals that are impacted by nonregional climatic events (El Nino), ultimately leading to improved water resource management applications on a regional scale. Editor’s note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series. 相似文献
474.
Anna Müller Vesalio Mora Edwin Rojas Jorge Díaz Obdulio Fuentes Estuardo Giron Ada Gaytan Jacob van Etten 《Disasters》2019,43(2):410-430
Drills are an important element of disaster management, helping to increase preparedness and reduce the risk of real‐time failure. Yet, they are not applied systematically to slow‐onset disasters such as a drought, which causes damage that is not instantly apparent and thus does not solicit immediate action. This case study evaluates how drills inform institutional responses to slow‐onset disasters. It spotlights Guatemala, a country where drought has severe impacts on livelihoods and the food security of small farmers. By implementing part of the Ministry of Agriculture, Livestock and Food's institutional response plan for drought, it explores how drills can help to detect issues in emergency response and to foster an institutional focus on improvements in preparedness. The results reveal that drills alone do not trigger institutional improvements if unsupported by a wider strategy that seeks to enhance capacities and protocols. These findings are valuable, however, in making problems transparent and in creating the space for discussion. 相似文献
475.
Nathaniel B. Guttman 《Journal of the American Water Resources Association》1999,35(2):311-322
ABSTRACT: The Palmer Drought Severity Index (PDSI) has been calculated for about 30 years as a means of providing a single measure of meteorological drought severity. It was intended to retrospectively look at wet and dry conditions using water balance techniques. The Standardized Precipitation Index (SPI) is a probability index that was developed to give a better representation of abnormal wetness and dryness than the Palmer indices. Before the user community will accept the SPI as an alternative to the Palmer indices, a standard method must be developed for computing the index. Standardization is necessary so that all users of the index will have a common basis for both spatial and temporal comparison of index values. If different probability distributions and models are used to describe an observed series of precipitation, then different SPI values may be obtained. This article describes the effect on the SPI values computed from different probability models as well as the effects on dry event characteristics. It is concluded that the Pearson Type III distribution is the “best” universal model, and that the reliability of the SPI is sample size dependent. It is also concluded that because of data limitations, SPIs with time scales longer than 24 months may be unreliable. An internet link is provided that will allow users to access Fortran 77 source code for calculating the SPI. 相似文献
476.
Andy Catley Dawit Abebe Berhanu Admassu Gezu Bekele Bayou Abera Gezahegn Eshete Tesfaye Rufael Tesfaye Haile 《Disasters》2009,33(4):665-685
Under a national Livestock Policy Forum in Ethiopia the impact of livestock vaccination during drought was assessed in order to inform the development of a best‐practice guideline. For each of the different types of vaccine used during drought years there was no significant difference in livestock mortality, for any species, in vaccinated compared with non‐vaccinated herds. The limited impact of vaccination on livestock mortality was attributed to weaknesses in the design and implementation of vaccination programmes, including use of inappropriate vaccines, low vaccination coverage, problems with vaccine dosing, incorrect timing of vaccination and problems with vaccine storage. If these weaknesses could be overcome vaccination could be a useful means to protect livestock assets, with considerable benefit‐cost ratios. Vaccination should be conducted as a standard preventive measure during normal years, and programme design should be informed by participatory epidemiological studies. 相似文献
477.
恢复力作为刻画人类自身响应和发挥主体能力、积极抵御和适应外界变化的指标,在灾害学领域的引入进一步丰富和明晰了灾害承灾体的性质,与脆弱性具有同等的重要性。但当前对灾害恢复力的研究不足,如何界定灾害恢复力的特征、诊断和定量评价恢复力尚存在较大的探讨空间。在湖南鼎城高排河流域野外土地利用现状测量与入户调查所得数据和气象数据的基础上,应用数学统计方法重点分析了土地利用、农户经济、文化素质状况等因素与农业旱灾承灾体恢复力的关系。结果表明,地貌类型与海拔高度从较大尺度上决定了农业旱灾承灾体恢复力的大小,水源地位置及其蓄水能力、水田与旱地的比例关系、劳动力文化水平、农户实际年收入和非农收入比例是影响农业旱灾承灾体恢复力的主要因素。 相似文献
478.
Adaptive Water Resource Planning in the South Saskatchewan River Basin: Use of Scenarios of Hydroclimatic Variability and Extremes
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David J. Sauchyn Jeannine‐Marie St‐Jacques Elaine Barrow Michael W. Nemeth Ryan J. MacDonald A. Michael S. Sheer Daniel P. Sheer 《Journal of the American Water Resources Association》2016,52(1):222-240
The South Saskatchewan River Basin is one of Canada's most threatened watersheds, with water supplies in most subbasins over‐allocated. In 2013, stakeholders representing irrigation districts, the environment, and municipalities collaborated with researchers and consultants to explore opportunities to improve the resiliency of the management of the Oldman and South Saskatchewan River subbasins. Streamflow scenarios for 2025‐2054 were constructed by the novel approach of regressing historical river flows against indices of large‐scale ocean‐atmosphere climate oscillations to derive statistical streamflow models, which were then run using projected climate indices from global climate models. The impacts of some of the most extreme scenarios were simulated using the hydrologic mass‐balance model Operational Analysis and Simulation of Integrated Systems (OASIS). Based on stakeholder observations, the project participants proposed and evaluated potential risk management and adaption strategies, e.g., modifying existing infrastructure, building new infrastructure, changing operations to supplement environmental flows, reducing demand, and sharing supply. The OASIS model was applied interactively at live modeling sessions with stakeholders to explore practical adaptation strategies. Our results, which serve as recommendations for policy makers, showed that forecast‐based rationing together with new expanded storage could dramatically reduce water shortages. 相似文献
479.
湖北省旱涝灾害的基本特征与成因分析 总被引:5,自引:0,他引:5
黄建武 《长江流域资源与环境》2002,11(5):482-487
湖北省是我国自然灾害多发省份之一,其中旱涝灾害尤为严重,是社会经济发展的一大制约因素。首先研究了湖北省旱涝灾害的基本特征,认为按出现时段,洪涝可分为梅涝、盛夏涝、春涝和秋涝,干旱可分为伏秋干旱、春夏干旱、秋季干旱和冬季干旱,因而具有季节性;各区灾害严重程度不同,干旱可分为鄂东北干旱严重区、鄂东中部伏秋旱严重区、鄂西北春夏旱严重区和鄂西南干旱不严重区,洪涝可分为鄂东中部和江汉平原梅涝区、鄂东北和鄂东南春梅涝严重区、鄂西南夏秋涝区和鄂西北和三峡河谷少涝区,因而具有区域性;此外,还具有延续性、阶段性、周期性和连发性等特征。分析了湖北省旱涝灾害形成的主要因素,认为旱涝灾害是在天气气候因素、地貌因素、环境资源因素、抗灾能力因素、社会经济因素等自然因素和人为因素的共同作用下产生和发展的;旱涝灾害的形成,自然条件固然很重要,但形成严重灾害,则与人为因素有密切关系,这在20世纪表现得尤为明显。 相似文献
480.