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为减轻季节性干旱对吉林西部农业生产造成的影响,以吉林西部6个气象站1957-2010年的月降水量资料为基础,采用标准化降水指数(SPI)作为气象干旱指标。利用Daubechies小波分析法、重标极差分析法(R/S)和干旱频率法对吉林西部SPI时空演化特征进行了研究。结果表明:研究区各站点冬旱整体上有减轻趋势,而秋旱有加重趋势;各站点气象干旱状况呈现出持续性特征,乾安(夏季和秋季)、前郭(夏季)、通榆(春季、夏季和秋季)、长岭(夏季)干旱持续性更加强烈。研究区春旱高频区为扶余,夏旱高频区为扶余和白城,秋旱高频区为白城、通榆、乾安、前郭和长岭,冬旱高频区为扶余、长岭和白城。研究结果可为吉林西部防旱减灾提供参考。 相似文献
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论气候变暖背景下干旱和干旱灾害风险特征与管理策略简 总被引：2，自引：0，他引：2
The drought is a most severe natural disaster worldwide, which leads to great risk in human being. The drought disaster and risk have more prominent because of obvious climatic warming in the last hundred years. At present, the understanding of the internal laws of the occurrence of drought and drought risk is not comprehensive, and the recognition of the characteristics of the drought and drought risk under climatic warming is obscure. In this paper, we summarized systematically the domestic and overseas research progress of the drought and drought disaster risk, introduced the principle of the drought disaster transfer process and the essential features of drought disaster, analyzed synthetically the main characteristics and interactions among the key factors of the drought disaster risk, discussed the effect of climatic warming on drought and drought disaster risk, and probed into the basic requirement of drought disaster risk management. Above all, we provide the main protective measurements of the drought disaster and the main strategy of drought disaster risk management. 相似文献
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Karen G. Villholth Christian Tøttrup Martin Stendel Ashton Maherry 《Hydrogeology Journal》2013,21(4):863-885
Groundwater drought denotes the condition and hazard during a prolonged meteorological drought when groundwater resources decline and become unavailable or inaccessible for human use. Groundwater drought risk refers to the combined physical risk and human vulnerability associated with diminished groundwater availability and access during drought. An integrated management support tool, GRiMMS, is presented, for the mapping and assessment of relative groundwater drought risk in the Southern African Development Community (SADC) region. Based on composite mapping analysis of region-wide gridded relative indices of meteorological drought risk, hydrogeological drought proneness and human groundwater drought vulnerability, the mapping results highlight consistent areas across the region with highest groundwater drought risk and populations in the order of 39 million at risk of groundwater drought at present. Projective climate-model results suggest a potentially significant negative impact of climate change on groundwater drought risk. The tool provides a means for further attention to the key, but neglected, role of groundwater in drought management in Africa. 相似文献
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Assessing Vulnerability to Agricultural Drought: A Nebraska Case Study 总被引：14，自引：6，他引：14
Recent drought events in the United States and the magnitude of drought losses indicate the continuing vulnerability of the country to drought. Until recently, drought management in many states, including Nebraska, has been largely response oriented with little or no attention to mitigation and preparedness. In 1998, Nebraska began to revise its drought plan in order to place more emphasis on mitigation. One of the main aspects of drought mitigation and planning is the assessment of who and what is vulnerable and why. This paper presents a method for spatial, Geographic Information Systems-based assessment of agricultural drought vulnerability in Nebraska. It was hypothesized that the key biophysical and social factors that define agricultural drought vulnerability were climate, soils, land use, and access to irrigation. The framework for derivation of an agricultural drought vulnerability map was created through development of a numerical weighting scheme to evaluate the drought potential of the classes within each factor. The results indicate that the most vulnerable areas to agricultural drought were non-irrigatedcropland and rangeland on sandy soils, located in areas with a very high probability of seasonal crop moisture deficiency. The identification of drought vulnerability is an essential step in addressing the issue of drought vulnerability in the state and can lead to mitigation-oriented drought management. 相似文献
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干旱等级具有多级和跃迁性质,有必要提出一种既能反映不同干旱等级变化特征,又能体现干旱总体变化特征的定量评估方法。通过构建干旱等级变化的概率矩阵,引入变化率乘子和变化程度乘子,推导干旱等级变化率和变化程度计算公式,提出干旱等级变化的综合定量评估方法;借助标准化降水蒸散指数和标准化径流指数,应用于东江流域评估月、季和年尺度的气象干旱向水文干旱传递过程中干旱等级变化及水库影响下水文干旱等级变化。结果表明:①气象干旱向水文干旱传递过程中干旱总体变化程度较小,但干旱等级变化明显,月、季和年尺度的总体变化率分别达到了45.9%、46.8%和34.9%;②干旱在10月下降了约1.4个等级,在春季上升了约1.3个等级;③水库径流调节对于缓解月、季尺度水文干旱作用显著,干旱等级总体变化率均约为33%,其中春季干旱程度下降了约1个等级。该方法不仅适用于评估干旱变化,也可应用于评估具有分级特征的其他灾害变化。 相似文献
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作为旱灾风险管理的核心内容和关键环节,旱灾风险评估逐渐成为旱灾研究的热点问题。从科学界定旱灾风险概念入手,辨析了干旱风险与旱灾风险之间的关系,并从机理上对旱灾风险形成机制进行了剖析和阐述;首次提出了旱灾风险定量评估总体框架,即通过建立干旱频率~潜在损失~抗旱能力之间的定量关系实现对旱灾风险的定量评估,并探讨了该评估框架所涉及的干旱频率分析技术、灾损评估技术、抗旱能力评估技术和旱灾风险表征技术等关键技术及其难点。 相似文献
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利用综合气象干旱指数(CI指数)和K干旱指数, 对贵州安顺地区1971-2011年41 a来气象干旱的时空分布状况、演变特征及突变情况进行了比较分析. 结果表明: 对严重的干旱时段, 两种指数均能表现出来, 对历年干旱过程及灾害的评定结果基本一致;CI指数对干旱的评定更为精细, 但K指数延续性更好;分季节的干旱分析中, 两种指数对于夏季出现干旱概率较小的结论一致, 对各季节平均干旱长度的评判基本一致. 对时间演变的线性变化趋势以及M-K检验结果对比分析表明, 春季和秋季干旱强度增强、夏季干旱强度减弱、年度平均干旱长度及春、秋季干旱长度增加的这几个趋势, 两种方法两种指数结果一致, 结论被认为是可信度较高的. M-K曲线检测表明: 年度干旱长度在2008年后为增加的趋势, 20世纪90年代以来春季干旱强度增强, 20世纪末以来夏季干旱强度趋于减轻, 秋季干旱强度增强, 1970年代中期后春季干旱长度有增加的趋势, 秋季干旱长度在20世纪80年代中期到90年代后增加的趋势可能发生了突变. 年度干旱强度存在12~14 a的长周期和年度干旱长度4~6a的短周期较为可信. 相似文献
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为有效应对日益严重的流域干旱问题,有必要开展面向干旱全过程的黄河流域干旱应对系统研究。基于干旱演变过程设计了干旱指数,通过天气预报模型、回归分析等进行干旱、需水与径流预报;设置多年调节水库旱限水位,实现水资源年际补偿;识别洪水和泥沙分期特征,采用分期汛限水位增加洪水资源利用量;建立了梯级水库群协同优化调度模型,调配抗旱水源。算例结果显示:黄河流域干旱应对系统能够平衡年际间的干旱损失以避免重度破坏,与实际情况相比,在重旱的2014年增加抗旱水源22.40亿m^3。建立的干旱应对系统已应用于黄河流域抗旱实践,提升了流域应对干旱的水资源调控能力。 相似文献
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区域气象干旱评估分析模式 总被引：1，自引：0，他引：1
为应对全球范围内日益严重的干旱问题,对区域气象干旱相对完整的评估分析模式开展了探讨。提出了从区域气象干旱识别到干旱特征值计算,再到干旱特征多变量分析的3个分析评估步骤。并以渭河流域为例,对研究区域进行了矩形干旱评估单元划分,选取了RDI（Reconnaissance Drought Index）为评估指标对区域内各单元各时段的干旱状态进行了识别,结果与历史记载的干旱年份吻合较好。分别采用了分布拟合、相关系数和Copula函数等统计学方法对区域干旱的干旱特征值（干旱历时、干旱面积、干旱强度和干旱频率）进行了特征分析,得出了一系列的单变量、双变量及多变量特征分析对比结果。通过对各类分布函数的计算和绘图,得到了渭河流域干旱事件发生的条件概率和重现期,形成了一套相对完整的区域干旱评估分析模式。 相似文献
11.
近30年雷州半岛季节性气象干旱时空特征 总被引：1，自引：0，他引：1
为进一步分析日尺度有效干旱指数(Effective Drought Index,EDI)的适应性,基于雷州半岛1984~2013年逐日降水资料进行验证,对比EDI和月尺度标准化降水指数(Standardized Precipitation Index,SPI)的干旱识别效果,进而结合线性趋势、M-K趋势检验和空间插值方法 ,分析雷州半岛季节性气象干旱时空特征。结果表明:(1)日尺度EDI和6个月时间尺度SPI(SPI-6)适用于雷州半岛的干旱监测,但EDI对严重干旱和突发干旱的识别比SPI-6更准确;(2)1984~2013年,雷州半岛秋冬季干旱频率和干旱站次比均呈减少趋势,但春夏季干旱频率和干旱站次比略有增加趋势;(3)春旱频率从南向北递增,重旱高频地区位于西北部,而夏季重旱高频区位于西部沿海;秋旱南部重于北部,高频中心在雷中西部沿海和曾家周边;冬季重旱以西部沿海、雷州市和徐闻县交界处频率最高。 相似文献
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Drought hazard assessment using geoinformatics over parts of Chotanagpur plateau region, Jharkhand, India 总被引：4，自引：3，他引：1
Swati Pandey A. C. Pandey M. S. Nathawat Manoj Kumar N. C. Mahanti 《Natural Hazards》2012,63(2):279-303
Recurrent drought events in the Palamu district of Jharkhand state and the magnitude of drought losses primarily toward agricultural production in this dominantly monocropped region indicate the continuing susceptibility of the society to drought. This paper presents a method for spatial, geoinformatics-based assessment of agricultural, meteorological, and hydrological drought hazard in Palamu district. It was hypothesized that the key climatic, biophysical and social factors that define agricultural drought hazard were soils, geomorphology, drainage density, land use, and relief, whereas for meteorological drought hazard, it is rainfall, coefficient of variation of rainfall and for hydrological drought hazard, it is lithology, depth to water table, aquifer yield, and surface water bodies. The framework for the derivation of an agricultural, meteorological, and hydrological drought hazard map was created through the development of a numerical weighting scheme to evaluate the drought potential of the classes within each factor. A cumulative map created through spatial join of all the three types of drought provided a drought hazard scenario in totality. The area with different severity of drought hazards under cumulative drought hazards scenario (viz. very low (8.9?%), low (24.2?%), moderate (29.2?%), high (20.13), and very high (17.3?%)) revealed high drought proneness of the area and the usefulness of geoinformatics in better spatial prognosis of drought hazards. 相似文献
13.
Upstream inflow decline and excessive water withdrawal are the major reasons for failure in maintaining ecological functions of wetlands and could lead to wetland drought and degradation. Quantitative evaluation of wetlands drought constitutes the basis for managing and scheduling water resources and guaranteeing biological safety. In the study, we proposed a Palmer wetland drought index (PWDI) based on the water balance model that describes wetland hydrological characteristics linked to its located basin to describe drought-reflected ecological characteristics in lacustrine Baiyangdian Wetland and compared it with Palmer drought severity index (PDSI). The results presented that PWDI is able to reflect the worst drought in history, and the drought is mainly affected by water stored in the wetland, but PDSI is inadequate for evaluating the wetland drought. The PWDI methodology provides a clear, objective approach for describing the intensity of drought and can be readily adapted to characterize drought on an operational basis. 相似文献
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提出不同网格干旱等级影响下的区域干旱指数。采用copula函数,建立了区域干旱历时和干旱强度的联合分布,计算联合分布的重现期,并对实际重现期作区间估计。所提出的区域干旱指数能够反映研究区域内发生干旱的严重程度和该区内不同干旱等级所影响面积的大小,且联合分布同时考虑了干旱历时和干旱强度,更全面地反映区域的干旱状况。重庆市2006年干旱实证分析表明,区域干旱指数能够较好地描述本次干旱的发生发展过程,并计算出联合分布的重现期为118年。 相似文献
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利用西北五省区137个测站的1961-2009年逐月降水量资料计算标准化降水指数(SPI), 统计了逐月、春末夏初、初夏、夏季及秋季的干旱、重旱、特旱的频率及面积率, 分析其时空变化特征.结果表明: 新疆北部、青海的中部及甘肃河西是西北地区干旱频率较高的区域, 干旱频率在15个月以上, 新疆南部除个别月份干旱发生频率较高外, 总体干旱发生频率较低;干旱发生区域随月份有由南到北、由西向东变化的趋势;除新疆、青海、及甘肃个别区域重旱频率超过5月外, 其他区域基本上都在5月以下;新疆南部重旱频率仍然较低;夏季发生范围高于其他季节;新疆北部、甘肃河西是特旱的高发区. 不同等级的月及季节干旱面积率其逐年变化具有相似的特征, 西北干旱面积率的变化总体上可以分为3个阶段: 1961-1980年干旱面积率比较高, 平均在35%左右;1981-1990年为转折期, 干旱面积率下降到15%左右;而1991-2009年为稳定期, 干旱面积率变化不大.全球气候变暖导致西北地区降水量、冰川融水量、河川径流量增加和湖泊水位上升、面积扩大, 是1987年以来干旱面积率下降的原因. 相似文献
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基于Copulas函数的二维干旱变量联合分布 总被引：1，自引：1，他引：0
通过构建干旱变量的联合分布揭示干旱演变规律,可作为干旱分析的重要手段。基于8种单参数族的Copulas函数进行新疆乌鲁木齐和石河子气象站二维干旱变量的联合分布。经拟合优度评价:Frank Copula对干旱历时和干旱烈度、干旱历时和烈度峰值的拟合度最好;Clayton Copula对于干旱烈度和烈度峰值的拟合效果最好。二维变量联合超越概率值随单变量值的减小而增大;单变量的重现期介于二维变量联合重现期与同现重现期之间。表明Copulas函数能够描述二维干旱特征变量的联合分布。 相似文献
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气象干旱发展到一定程度可以传递为水文干旱。以潘家口水库流域1961—2010年逐月平均降水数据和潘家口水库的入库径流序列为基础数据,分别计算了1、3、6、12个月时间尺度的标准化降水指数（SPI）和标准化径流指数（SRI）,以表征研究区域的气象干旱和水文干旱。基于条件分布模型,分析了不同时间尺度的气象干旱传递到未来的不同等级和不同的预测期（或滞后期）的水文干旱的概率。结果表明,当SPI时间尺度较短或预测期（滞后期）较短时,其对应的SRI水文干旱等级越倾向于维持与SPI相同的干旱等级;随着SPI时间尺度的增长或预测期（滞后期）延长,其对应的SRI水文干旱等级略低于气象干旱或恢复到正常状态。 相似文献
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Tsegaye Tadesse Donald A. Wilhite Sherri K. Harms Michael J. Hayes Steve Goddard 《Natural Hazards》2004,33(1):137-159
Drought has an impact on many aspects of society. To help decision makers reduce the impacts of drought, it is important to
improve our understanding of the characteristics and relationships of atmospheric and oceanic parameters that cause drought.
In this study, the use of data mining techniques is introduced to find associations between drought and several oceanic and
climatic indices that could help users in making knowledgeable decisions about drought responses before the drought actually
occurs. Data mining techniques enable users to search for hidden patterns and find association rules for target data sets
such as drought episodes. These techniques have been used for commercial applications, medical research, and telecommunications,
but not for drought. In this study, two time-series data mining algorithms are used in Nebraska to illustrate the identification
of the relationships between oceanic parameters and drought indices. The algorithms provide flexibility in time-series analyses
and identify drought episodes separate from normal and wet conditions, and find relationships between drought and oceanic
indices in a manner different from the traditional statistical associations. The drought episodes were determined based on
the Standardized Precipitation Index (SPI) and Palmer Drought Severity Index (PDSI). Associations were observed between drought
episodes and oceanic and atmospheric indices that include the Southern Oscillation Index (SOI), the Multivariate ENSO Index
(MEI), the Pacific/North American (PNA) index, the North Atlantic Oscillation (NAO) Index, and the Pacific Decadal Oscillation
(PDO) Index. The experimental results showed that among these indices, the SOI, MEI, and PDO have relatively stronger relationships
with drought episodes over selected stations in Nebraska. Moreover, the study suggests that data mining techniques can help
us to monitor drought using oceanic indices as a precursor of drought. 相似文献
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以鄱阳湖流域为研究区, 基于2011—2020年22个墒情站的逐日地面墒情监测数据、1956—2020年49个雨量站的日降雨数据及2016—2019年墒情站所在灌区的气象数据, 采用考虑植被生理状态的土壤水分亏缺指数(SWDI)表征农业干旱, 分析不同尺度下墒情、包气带缺水量和降水量的时空分布, 评估SWDI在鄱阳湖流域农业干旱监测中的适用性, 揭示该流域农业干旱时空演变特征及其对气象干旱的响应规律, 初步探讨土壤质地与农业干旱强度的相关性。结果表明: ① SWDI对鄱阳湖流域农业干旱诊断具有较好的适用性; ②近10 a该流域农业干旱呈显著加重趋势, 其中2019—2020年发生流域性重度农业干旱, 且夏、秋、冬连旱, 是近10 a的主导季节性农业干旱, 对水稻、油菜等粮食产量影响显著; ③相较于气象干旱, 农业干旱发生、结束时间分别平均约晚2.5周和3周, 历时长10.1周, 频次更低, 干旱等级更小; ④砂土持水性最差, 易发生特大农业干旱, 黏土、黏壤土保水性最好, 轻旱和中旱发生概率较大, 壤土、砂壤土和壤砂土则介于二者之间。 相似文献