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1.
全球气候变化影响了气象水文要素的时空分布特性,气象水文干旱事件的转化关系及风险传播特征亟待研究。基于站点、栅格观测资料和CMIP5（Coupled Model Inter-comparison Project Phase5）的19个气候模式输出数据,采用新安江等4个水文模型模拟了中国135个流域历史（1961—2005年）和未来时期（2011—2055年,2056—2100年）的水文过程,计算了SPI（Standard Precipitation Index）和SRI（Standard Runoff Index）干旱指标,通过游程理论识别了气象干旱与水文干旱事件,利用Copula函数与最大可能权函数度量二维干旱风险特征,定量评估了气象干旱至水文干旱的潜在风险传播特性。结果表明:①气象-水文干旱对气候变化响应强烈,华北和东北地区的干旱联合重现期增大,干旱潜在风险减小,华中和华南地区的干旱联合重现期减少60%~80%,干旱潜在风险增加;②气象干旱与水文干旱风险在历史和未来时段均存在显著的正相关关系,相关系数超过0.99;③各流域水文干旱风险变化对气象干旱风险变化的敏感程度不会随气候变暖发生较大变化,但未来北方地区水文干旱同气象干旱同时发生的概率将会小幅度增加。 相似文献
2.
K. Sreelash Rajat Kumar Sharma J. A. Gayathri B. Upendra K. Maya D. Padmalal 《Journal of the Geological Society of India》2018,92(5):548-554
The Western Ghats plays a pivotal role in determining the hydrological and hydroclimatic regime of Peninsular India. The mountainous catchments of the Ghats are the primary contributors of flow in the rivers that sustains the life and agricultural productivity in the area. Although many studies have been conducted in the past decades to understand long term trends in the meteorological and hydrological variables of major river basins, not much attention have been made to unfold the relationship existing among rainfall and river hydrology of natural drainages on either side of the Western Ghats which host one of the unique biodiversity hotspots across the world. Therefore, an attempt has been made in this paper to examine the short term (last three decades) changes in the rainfall pattern and its influence on the hydrological characteristics of some of the important rivers draining the southern Western Ghats as a case study. The short term, annual and seasonal trends in the rainfall, and its variability and discharge were analyzed using Mann-Kendall test and Sen’s estimator of slope. The study showed a decreasing trend in rainfall in the southwest monsoon while a reverse trend is noticed in northeast monsoon. Correspondingly, the discharge of the west and east flowing rivers also showed a declining trend in the southwest monsoon season. The runoff coefficient also followed the trends in the discharge. The runoff coefficient of the Periyar river showed a decreasing trend, whereas the Cauvery river exhibited an increasing trend. A high-resolution analysis of rainfall data revealed that the number of moderate rainfall events showed a decreasing trend throughout the southern Western Ghats, whereas the high intensity rainfall events showed an opposite trend. The decline in groundwater level in the areas which recorded an increase in high intensity rainfall events and decrease in moderate rainfall events showed that the groundwater recharge process is significantly affected by changes in the rainfall pattern of the area. 相似文献
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鄂西岩溶槽谷区洼地的水位响应特征及产流阈值估算 总被引：1，自引：0，他引：1
以湖北省兴山县黄粮镇刘家坝和龙湾两处岩溶洼地作为研究对象,利用其降雨、水文和土壤水等监测数据,探讨灌入式补给条件下洼地汇流的水位响应特征和产流特点,并基于降雨量和洼地内明渠流量的关系,采用数学拟合方程,估算两处洼地的降雨产流阈值,进而分析了影响产流阈值的因素。结果表明:降雨强度增大,产流阈值减小;土壤前期含水率越大,越有利于坡面产流;落水洞和岩溶泉水位与降雨有较好的同步响应关系,水位变化曲线随雨强大小分别表现出“陡升陡降”和“缓升缓降”的特点;刘家坝和龙湾洼地的产流阈值分别为7.4 mm和10.6 mm。 相似文献
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Natural Hazards - To investigate the propagation of meteorological droughts to agricultural and hydrological droughts, the relationship between droughts was analyzed using observed precipitation... 相似文献
6.
The relation between karst spring discharge and rainfall by cross-correlation analysis (Campania, southern Italy) 总被引：4，自引：2，他引：2
The relation between rainfall and the discharge from two springs, located at the base of different karst massifs in southern Italy, is investigated by cross-correlation analyses. Data are derived from a continuous time window of 13 years. The input signal involves multiple rainfall time series (cumulative rainfall over varying time windows), while the time series of daily spring discharges are used as the output signal. Analyses were first conducted on the unprocessed data and then on data for which linear trends and seasonal components had been removed, the latter by a spectral analysis. Analyses contributed to the investigation of the time required for water to flow through the karst aquifers at the two sites. Long time intervals of the cumulative rainfall (>60 days) appear to be the main component affecting the spring discharge hydrographs; shorter time intervals seem to be related to quick-flow paths. Some statistics about the linear regression and the meaning of the cross-correlation analysis are discussed. Cross-correlation analysis can provide strong support for identification of the main rainfall contribution and the travel time through the main infiltration pathways in aquifers. 相似文献
7.
近年来云南持续发生严重干旱,云南干旱是否日趋"常态化"成为社会各界关心的一个热点问题,相关报道不断见诸媒体。本文从水文的角度对云南省的历史干旱、水文要素以及趋势预测等方面进行了深入的分析。在历史依据和现代气象水文观测数据的支撑下,考察近100年来全球增暖可能导致部分地区干旱化的可能,从而认为近年来提出的云南干旱"常态化"存在科学依据;但干旱"常态化"仅能局限于近现代时期这一时间范畴,对于今后更长时期云南省干旱发展趋势,依据现有技术手段及研究成果尚难以判断把握。 相似文献
8.
Droughts occur when rainfalls diminish or cease for several days, months or years. In the last five years several meteorological droughts have occurred in Venezuela, impacting negatively water supply, hydro-power and agriculture sectors. In order to provide institutions with tools to manage the water resources, a probabilistic model has been developed and validated to predict in advance the occurrence of meteorological droughts in the country using monthly series of 632 rainfall stations. The standardized precipitation index (SPI) was used to identify dry events of each rainfall series. A principal component analysis associated to a geographic information system was used to define geographically continuous homogeneous sub-regions (HS) for the values of SPI. For each HS a representative station was selected (reference station, RS). A lagged correlation analysis was applied to the SPI series of the RS and the corresponding series of anomaly indices of 10 macroclimatic variables (MV). The four MV with higher correlation in each RS were organized into three levels (-1, 0 and +1), using the quartiles Q2 and Q4 as values of truncation. The SPI series are expressed in four ranges: non-dry, moderately dry, severely dry and extremely dry. The conditional probability of occurrence of the four ranges of SPI was determined in every combination that can occur in the four VM best correlated. The resulting model in each RS was validated using the SPI series from 20 meteorological stations operated by the Servicio de Meteorología de la Fuerza Aérea Venezolana (Meteorological Service of the Venezuelan Air Force) which were not used in the development of the models. Results indicate that models detected the occurrence of ES with an accuracy ranging from 85.19 to 100%; the success is directly proportional to the length of records used in the development of the model. This methodology could be applied in any country that has long, continuous and homogeneous rainfall series. 相似文献
9.
对区域干旱的概念和计算方法进行了研究,认为干旱问题应根据不同的干旱特征分区进行研究并提出针对性的解决措施。干旱研究不仅要考虑到干旱的水文特征,而且要考虑干旱风险所带来的后果。提出了分析干旱问题的理论框架。并将黄河下游引黄灌区划分为6个子区,应用多变量随机模型生成了月降水量资料系列。利用了33年的月降水量资料率定模型参数。应用生成的月降水量系列从理论风险性的观点研究了区域干旱问题。 相似文献
10.
环境变化影响区域水资源的可持续开发利用,导致水文过程出现非平稳特征,需发展非平稳水文干旱评估方法。选取渭河流域为研究区,依据流域内2个水文站、62个雨量站和24个气象站1961-2013年数据,基于可变下渗容量模型定量分离气候变化和人类活动对径流衰减的贡献;采用标准化径流指数（Standardized Runoff Index, SRI）剖析水文干旱时空演变特征;提出多种SRI参数化方案,对比评定各方案表征非平稳干旱的合理性以及环境变化对干旱演变的影响作用。结果表明:自1991年以来渭河流域年径流量呈显著衰减趋势,人类活动是径流演变的主要因素,对咸阳和华县站径流量变化的贡献率分别为-66.7%和-71.0%;时变参数方案计算的干旱指数能合理重建历史水文干旱序列;人类活动是渭河流域1991年以来短历时水文干旱发生的主导因素,气候变化主要影响长历时旱涝的演变趋势。 相似文献
11.
The major obstacles for modelling flood processes in karst areas are a lack of understanding and model representations of
the distinctive features and processes associated with runoff generation and often a paucity of field data. In this study,
a distributed flood-modelling approach, WetSpa, is modified and applied to simulate the hydrological features and processes
in the karst Suoimuoi catchment in northwest Vietnam. With input of topography, land use and soil types in a GIS format, the
model is calibrated based on 15 months of hourly meteorological and hydrological data, and is used to simulate both fast surface
and conduit flows, and groundwater discharges from karst and non-karst aquifers. Considerable variability in the simulation
accuracy is found among storm events and within the catchment. The simulation results show that the model is able to represent
reasonably well the stormflows generated by rainfall events in the study catchment. 相似文献
12.
Amrit Kumar Pandey Rajendra P. Mishra Surendra K. Daradur Mihail 《Natural Hazards》2018,92(2):1199-1210
The frequency and severity of occurrence of meteorological droughts in different climatic regions depend on regional climatic factors. This study has made an effort to explore the relationship of range of annual temperature variation at a given place with the frequency of occurrence of drought and the maximum magnitude of seasonal rainfall deficit (i.e., severity). The seasonal rainfall refers to sum of monsoon season (rainy season) rainfall in India. The monthly precipitation data of 113 years (1901–2013) for 256 stations in different parts of India have been used to estimate the return period of meteorological drought at different stations. The daily normal values of observed maximum and minimum temperatures from 40 years of records have been utilized to estimate range of temperature variation (θR) during the year at each stations. In various parts of India, the θR ranges from 10 °C in humid regions to 40 °C in arid regions. The various climatic regions have been experiencing maximum deficiency of annual rainfall ranging from 30% (humid) to 90% (arid). The results reveal that places exhibiting θR values between 40 to 30 °C face more frequent droughts with average frequency of once in 3 to once in 6 years. The occurrence of extreme and severe drought events is more frequent in the regions with higher values of θR compare to that in lesser values of θR. The regions with θR values between 30 to 25 °C mostly face severe and moderate events having the average drought return period of 6–9 years, and the occurrence of extreme droughts in these regions is rare. Furthermore, regions with θR?<?20 °C face moderate droughts only with an average return period of 14 years. This study divulges that the average return period and magnitude of deficiency of drought events have notable relationship with the range of temperature variation during the year at a given place.
相似文献13.
潮水洞无降雨补给时仍有规律的间歇性流出,是典型的岩溶间歇泉,其流量、水化学动态规律及形成机制缺乏系统的研究.基于长期水文气象观测和水化学测试数据,分析了潮水洞不同时期流量、水温和电导率变化特征以及潮水洞岩溶水系统的水化学特征.潮水洞为多个岩溶水子系统的连接,其动态呈现为雨期和无雨期两个不同特征,且存在多个不稳定周期的间歇出流过程.通过c(Mg2+)/c(Ca2+)比值及水文动态特征辨识出间歇出流的地下水来源为天河板组灰岩含水层,随着过程流量的不断增加,深循环地下水占比最高达97%.结合水文地质条件概化出潮水洞岩溶水系统循环模式,天河板组灰岩含水层内虹吸管道的发育是间歇性动态特征的主要成因. 相似文献
14.
Water management and engineering in the karstic High Atlas of Morocco are difficult tasks under the prevailing geological, hydrogeological, geomorphological, vegetational and climatic conditions. It is important to be able to understand and predict the characteristics and availability of water for future water planning in the region under changing climatic and agricultural conditions. An interdisciplinary analysis of problems and adequate hydrological modelling tools developed by geologists, hydrologists and biologists are necessary. The karst areas of the High Atlas Mountains are characterised by impermeable triassic basalt underlying substantial subsurface reservoirs with high potential discharge rates. The karst groundwater aquifers are extensive but largely unknown in dimension, probably with a hierarchical network of groundwater flow paths. It is estimated that approximately 70% of the surface water is directly lost to groundwater. Steep landslide- and debris flow prone slopes exist next to coarse-grained, highly porous river beds. Infrequent, high intensity rainfall or snowmelt causes a particularly high flood risk to these karst areas. In addition, agriculture and land use changes have degraded the karst areas. The most important driving forces for degradation include permanent overgrazing even during droughts and the use of firewood by a continually growing population. Large scale degradation of vegetation has occurred in the oro-mediterranean (mountainous Mediterranean) zone, between 2600 and 3400 m which coincides with the most important zone for karstic groundwater creation. The combination of high amounts of groundwater flow and rapid surface flow due to sparse vegetation has increased the problems of flood flow. 相似文献
15.
This study analyses regional drought characteristics (frequency, severity, and persistence) of meteorological droughts occurred in the northwestern parts falling under arid and semiarid regions of India with mean annual rainfall ranging between 100 and 900 mm. A drought is defined as a season or a year with rainfall less than 75% of corresponding mean at a place. Long-term monthly rainfall records (1901–2013) of 90 districts of north-west India located in the states of Punjab, Haryana, Rajasthan and Gujarat are used in the analysis. The percentage departure of seasonal rainfall from long-term average rainfall has been used for identification of onset, termination, and quantification of drought severity. The average frequency varied from once every 3–4 years. The westerly districts have an average drought return period of 3 years, while districts lying toward the east had droughts once every 4 years. Only four of the 90 districts in the study area experienced droughts once every 5 years. Persistent droughts of 2, 3, and 4 year duration occurred widely. Severe droughts occurred in the years 1904, 1905, 1911, 1918, 1931, 1939, 1985, 1986, 1987, 1993, and 2002, with an average frequency of severe drought events of one in 10 years. The analysis presented in this paper improves understanding of the regional drought characteristics and will inform drought mitigations and strategies in these arid and semiarid areas. 相似文献
16.
为了查明山西省晋祠泉泉水断流、泉口水位下降及近年来泉口水位回升的原因,为泉水复流工作提供理论参考,以长系列气象、水文、开采量、泉流量、地下水位等资料为基础,在详细分析了晋祠泉域不同水动力分区年内、年际动态特征的基础上,从自然气候与人类活动两方面出发,阐述了不同历史时期晋祠泉域岩溶水位变化的影响因素。结果表明：1956-1994年,因20世纪80、90年代人工开采量达到历史高峰期,一度超过2.4 m3/s,且80年代以后我国北方干旱化发展趋势较为严重,晋祠泉水流量逐渐减小直至断流;1994-2008年,人工开采量虽有一定程度减少,但仍维持在2.0 m3/s左右,且恰逢连续枯水年,降水量、河流径流量较多年平均值分别减小了11%和27%,此阶段泉口水位快速下降至历史最低值;2008年以后进入相对丰水期,在采取多项措施减少泉域岩溶水开采量的同时,汾河二库蓄水水位逐步抬高,其对岩溶水的渗漏补给量在经历了约2 a的滞后期后到达泉域排泄区,晋祠泉口水位近年来逐步回升。 相似文献
17.
Ding Hairong Li Yong Shao Chongjian Lauvence Svirchev Xu Qiang Yan Zhaokun Yan Liang Ni Shijun Shi Zeming 《Journal of Earth System Science》2017,126(7):96
By analyzing the multi-year runoff and rainfall data at 15 hydrological stations from 1980 to 2007, as well as monthly runoff data from 1964 to 1984 at the Zipingpu hydrologic station, the relationship between precipitation and runoff has been established and the trend was explored. Based on the catastrophic floods of August 13 and August 18, 2010, characteristics and control factors on the post-seismic floods are summarized. Firstly, the Wenchuan earthquake and rupture zone provides the background for post-seismic floods to develop in the upper Minjiang River, which follows a post-seismic disaster-chain pattern: earthquake collapse to landslide debris flows to floods. Secondly, heavy rainfall controlled by the orographically-enhanced precipitation after the Wenchuan earthquake is the trigger factor for the development of devastating post-seismic floods. Thirdly, the post-seismic floods contain high sediment discharge, cause abrupt and severe damages, and have a large of volume and higher frequency. 相似文献
18.
The karst hydrological processes are the response of karst groundwater system to precipitation. The precipitation penetrates through the vadose zone, the subsequent groundwater pressure wave propagates to a spring outlet, and then, the spring discharge changes. This paper proposes a grey auto-incidence analysis for studying the karst hydrological processes. The method can detect the periodicity of a time series, for example, precipitation and spring discharge. Then the approach is applied to Liulin Springs Basin, China. The results show that the auto-incidence degree of precipitation reaches to the maximum (i.e., 0.816) when time delay equals to 8 years. The auto-incidence degree of spring discharge reaches to the maximum (i.e., 0.865) when time delay equals to 3 years. These results show that the periodicity of precipitation is 8 years, and of spring discharge is 3 years. The difference of periodicity between the precipitation and the spring discharge reveals that the processes of precipitation recharging groundwater and groundwater transport are regulated or controlled by karst aquifer. Because of heterogeneity of karst aquifer, the quick flow and base flow occur during the groundwater propagation, which causes the periodicity of spring discharge is not coincidence with of precipitation. 相似文献
19.
José Antonio Cuchí David Chinarro José Luis Villarroel 《Environmental Earth Sciences》2014,71(3):1049-1060
Black box identification techniques are very useful tools to study the relationship between rainfall and the discharge of karst aquifers. Autocorrelation, cross-correlation, cross-spectral, impulse response identification (Wiener–Hopf and error minimization methods) and parametric identification of transfer functions techniques have been used by different authors. A review of these techniques has been realized to assess the possibilities and limitations. The reviewed techniques are applied to a time rainfall–discharge series of Fuenmayor karst spring, (southern central Pyrenees, Spain) to establish the relative quality of the obtained models. The quality is evaluated with the Nash–Sutcliffe model efficiency coefficient. In addition, effective rainfall has been used to improve the performance of every model. The whitening technique has been used in the cross-correlation technique with good results. The studied spring shows a Fontestorbes type behavior. The linearity of the system has been analyzed by the coherence function. Fuenmayor has an acceptable linear response, except for high frequency events. The parametric identification provides the best efficiency value E = 0.8164 and provides a proper transfer function, with five parameters (one zero, two poles, the gain and the delay). The prediction power of this transfer function is validated with another time series, with an efficiency value of E = 0.7904. 相似文献
20.
A conceptual model of the functioning of a complex coastal karst aquifer in southern Spain is presented. The system has well developed conduits below sea level and is connected to the Mediterranean Sea. It discharges through two conduits 12 m below sea level, 20 km apart. The Moraig conduit is the main outlet; the discharge to the sea is brackish. The Toix conduit only discharges to the sea during heavy floods and lets in seawater the rest of the time. During the 1999–2000 hydrological year, both conduits were monitored by flowmeters and electrical conductivity-temperature probes. On the basis of the collected data, the hydrological relationship between the functioning of the system and the sea was characterised. The conceptual model assumes the existence of a huge reservoir called an “aquifer reservoir” which is supplied by (1) freshwater from rainfall and (2) seawater flowing into the Toix conduit. In addition, during heavy rainfall events, fast infiltration brings considerable amounts of freshwater into the Moraig conduit. This is typical of a “by-pass” mechanism. Salinity and flow rates were simulated with the use of a rainfall-discharge and a rainfall-salinity model. The simulation of flow and salinity time series can be used for water management purposes. 相似文献