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1.
受全球气候变化影响,澜沧江-湄公河流域气象水文干旱发生了较大变化,预测未来流域干旱的时空变化与传播特征是应对气候变化、开展澜湄水资源合作的基础。利用SWAT模型通过气陆耦合方式模拟了澜沧江-湄公河流域历史（1960—2005年）和未来时期（2022—2050年,2051—2080年）的水文过程,采用标准化降水指数和标准化径流指数预估并分析了流域未来气象水文干旱时空变化趋势。结果表明:①澜沧江-湄公河流域未来降水呈增长趋势,气象干旱将有所缓解,但降水年内分配不均与流域蒸发的增加,将导致水文干旱更为严峻,干旱从气象到水文的传播过程加剧;②水文干旱具有明显的空间异质性,允景洪和清盛站的水文干旱最为严重,琅勃拉邦、穆达汉和巴色站次之,万象站最弱;③未来流域水文干旱事件发生频次略有减少,但其中重旱、特旱事件占比增加,极端干旱将趋多趋强,且空间变化更加显著。 相似文献
2.
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
3.
单变量水文统计中一些广为接受的概念在多变量环境下尚缺乏深入分析,也易被误解,如N年内重现期大于等于T的多变量事件发生的次数与N/T的关系。实践中,多变量联合重现期与其边缘分布变量重现期的一些经验关系被发现并通过了案例验证分析,但缺乏解释和推导。基于GH Copula推导了双变量联合重现期与边缘分布变量重现期的关系以及双变量事件发生次数与其重现期、变量相关程度间的定量关系。以昆明56年的逐月SPI(Standardized Precipitation Index)和SRI(Standardized Runoff Index)识别了干旱事件,采用GH Copula构建了干旱历时和烈度的联合分布函数,验证了双变量联合重现期与边缘分布变量重现期的关系以及多变量事件发生次数与其重现期的定量关系。表明不宜以“and”第1重现期是否接近于比该干旱事件的旱情更重的干旱发生的平均时间间隔来说明干旱特征值重现期分析的合理性。变量的相关性不强时,需谨慎采用边缘分布变量重现期的较大值近似代替“and”事件的第1重现期。 相似文献
4.
1957—2019年昆仑山北麓车尔臣河流域水文情势及其对气候变化的响应 总被引：1，自引：0，他引：1
气候变暖背景下干旱区水文、水资源的变化仍是影响区域水资源利用和洪水灾害防治的关键科学问题。基于1957—2019年长序列的水文、气象资料,系统分析了昆仑山北麓车尔臣河流域的水文变化特征及其对气候变化的响应。总体上,车尔臣河流域的水文过程的显著变化发生在1990s末期,变化前后年径流量约增加了54.67%,所有季节径流的增加共同造成了年径流的增加,其中夏季径流的增加对年径流增加的贡献最大,其次依次为秋季、春季和冬季。降水增加（第一控制因素）和气温升高（第二控制因素）共同造成了车尔臣河流域水文过程的变化。具体到径流年内变化,降水是春夏季径流变化的主控因素,而秋冬季径流变化的主控因素是气温。径流增加为中下游提供更多水资源的同时,也导致年际间水文洪涝和干旱事件发生的频率增加、强度增强。冰冻圈在该地区水文循环中起着重要的作用,但其对水文过程的影响仍不明确,加强阿尔金高山区的冰川、多年冻土监测将为进一步预估水文对气候变化的响应提供基础数据支撑。 相似文献
5.
在干旱事件不确定性和枯期径流变异性的双重影响下,水文干旱特征时序非一致性问题为其联合分布模拟带来困难。基于东江干流测站日径流过程数据,采用游程理论提取水文干旱事件,并结合干旱特征均值变化、时序一致性分析及边缘分布模拟,以确定干旱事件融合及剔除评判标准的合理取值。基于Rosenblatt变换Cramer-von Mises检验统计量拟合方法,构建水文干旱特征两变量联合分布Copula模型,并根据同频法设计两变量组合值。通过对比枯期径流变点分隔子序列干旱特征,分析变化环境下东江流域水文干旱特征及缺水响应。结果表明:水文干旱事件融合和剔除的评判标准值分别取0.1和0.3比较合理。干旱特征两变量之间具有较高的正相关性,但不同时间系列不同变量之间的联合分布及边缘分布最优模型并不一致。流域水库尤其是新丰江水库的径流调节作用,对于缓解东江中下游水文干旱效果明显,超阈联合重现期为2年的设计干旱持续时间、总缺水量和最大日缺水量分别减少了63%~71%、71%~84%和30%~47%,但如果要满足东江河道内最小管理流量目标,其依然分别达到了12~18 d、6 114万~9 030万m3和715.0万~929.0万m3。 相似文献
6.
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
7.
基于黄河源区1961—2017年逐月气象数据和两期（1980、2015年）土地利用数据集,通过设定多种变化情景,耦合SWAT(soil and water assessment tool)水文模型,探明流域内气候和土地利用变化与蓝绿水的时空响应关系。结果表明：时间上,气候变化情景下,流域内蓝水量减少了16.74 mm/a,绿水量增加了19.52 mm/a;土地利用变化情景下,流域内蓝水量减少了1.9 mm/a,绿水量增加了3.46 mm/a;在气候变化和土地利用变化共同作用下,流域内蓝水量减少了10.09 mm/a,绿水量增加了13.39 mm/a;同时,气候变化对蓝/绿水的贡献率均超过140%,是流域蓝绿水量变化的主导因素;空间上,流域内多种变化情景下,蓝/绿水量在流域内自西北至东南逐渐增加。研究结果将为黄河源区流域水资源调度计划制定提供科学参考。 相似文献
8.
环境变化下水文干旱研究是水科学研究领域的热点问题之一。根据荆南三口河系1956-2017年5个水文站和22个气象站实测数据,采用标准化径流指数（Standardized Runoff Index,SRI）、降水-径流多元非线性模型、累积量斜率变化率比较法辅以Mann-Kendall检验法等方法,分析环境变化前后荆南三口河系62年水文干旱演变特征,并定量分解气候变化（降水量、蒸发量）和人类活动对径流量衰减的影响。结果表明：荆南三口河系整体干旱频率较高,变化期干旱事件发生频次多且等级高,多尺度干旱平均频率达42.96%,稳定期极少出现干旱现象;三口地区年径流量、年蒸发量在长时间序列上均呈下降趋势,年降水量较为稳定,年径流量检验的突变年份为1970年、1985年和2003年;人类活动是促使三口河系年径流量逐渐衰减的主要原因,1971-1985年、1986-2003年和2004-2017年三个时期人类活动对径流量变化（水文干旱演变）影响的贡献率依次为91.14%、103.73%、78.33%。 相似文献
9.
气候变化对洪水灾害影响研究进展 总被引：2，自引：1，他引：1
气候变化背景下包括洪水在内的极端天气与气候事件频发已引起国际社会的广泛关注,研究气候变化对洪水灾害的影响既是全面理解气候变化影响的重要内容,也是减轻洪水灾害风险的实际需要。从气象水文和灾害风险两大领域综述了气候变化对洪水灾害影响的研究进展,从反映洪水灾害系统的雨情、水情和灾情角度,全面总结了当前国内外对极端降水、极端径流和洪水损失的变化及归因研究,梳理了研究方法与研究成果方面的主要进展及存在的问题,并探讨了未来的研究方向。指出加强数据积累,完善气候模式与水文模型的耦合,加强承灾体脆弱性及其变化的评估,综合洪水致灾过程与灾情结果的分析,推动气象水文与灾害风险学科领域的交叉研究应成为未来研究的重点。 相似文献
10.
潜在蒸散量（PET）是干旱监测评价的重要指标,分析影响潜在蒸散发的气候敏感因子对揭示气候变化的水文响应机理尤为重要。常采用的局部敏感性方法不适用于非线性模型且难以评估各气象因子间的相互作用。对此,基于1964—2018年西北旱区内163个气象站的监测数据,通过Penman-Monteith公式,采用Sobol全局敏感性方法分析了西北旱区潜在蒸散发的气候敏感因子,计算得到了自校准帕默尔干旱指数（scPDSI）,进而分析了区域干旱的时空演变特征。结果表明:1964—2018年西北旱区年均潜在蒸散量为1157.8 mm,高值出现在新疆东部与内蒙古西部地区,低值出现在青海南部地区。1993年为转折点,西北旱区潜在蒸散发受气温、日照时数、风速、相对湿度等多种因素综合影响由显著下降的趋势转变为显著上升,且在夏季最为明显。在1964—1993年,净辐射、风速与相对湿度的变化对潜在蒸散发的影响较大;在1994—2018年,风速与相对湿度的变化对潜在蒸散发的影响较大。scPDSI的时空分布表明新疆北部、青海中部以及甘肃境内的干旱有缓解的趋势;而黄河流域西南部干旱呈现加重趋势,将加剧区域水资源紧张,威胁生态安全。 相似文献
11.
The Ningxia Hui Autonomous Region of China (Ningxia), one of main agriculture areas in northwest China, has been severely affected by drought. Based on observed meteorological data, outputs of 20 global climate models and drought disaster data, future climate change and relevant drought hazard in the twenty-first century were projected in Ningxia, with the scenarios of RCP2.6 and RCP4.5; the risks of people, crop, and agriculture economy to drought disasters are quantitatively assessed, with the application of physical vulnerability curve models, probability distribution functions and Monte Carlo simulation method. It is found that the climate in Ningxia is likely to have a warming and wetting tendency in the twenty-first century. The extent of drought hazard is likely to increase. The increase rate is greater under RCP4.5 than that under RCP2.6. In general, the risks of population, crop, and agriculture to drought disasters are likely to increase in Ningxia in the twenty-first century. The magnitude of increase is likely to reach the greatest in the immediate term (2016–2035), followed by the increase in the medium term (2046–2065), and the long term (2081–2100). In comparison with RCP2.6, the drought disaster risks under the scenario of RCP4.5 are likely to increase further in three periods of the twenty-first century. The findings of this work have potential to provide data support for drought disaster risk management and support risk-based decision-making.
相似文献12.
The main objective of the Effects of Climate Change On the Inland waterway Networks (ECCONET) EU FP7 project was to assess the effect of climate change on the inland waterway transport network with special emphasis on the Rhine and Upper Danube catchments. The assessment was based on consolidation and analysis of earlier and existing research work as well as application of existing climate change and hydrological modelling tools. A key premise at the planning stage of the project had been that all impact studies conducted within ECCONET should be comparable with each other. This can be guaranteed by the common meteorological and hydrological basis. The climate model simulations, which are the most physics- and process-oriented tools for projecting the future climate evolution, include several uncertainties. In addition, uncertainties exist in the hydrological model simulations. In ECCONET, an effort was made to quantify the uncertainty range by using “representative projections” that represent both the lower and upper signals of hydrological low-flow parameters for 2021–2050 over the Rhine catchment. Their evaluation indicated that the finally chosen two regional climate model simulations could be applied also for the Upper Danube catchments as representative projections. The raw climate model outputs have been corrected to the observation data set through application of the linear scaling and the delta-change method. The first impact studies carried out after validation of the hydrological models resulted in discharge scenarios used as input to the economic models in ECCONET. 相似文献
13.
Drought identification and drought severity characterization are crucial to understand water scarcity processes. Evolution of drought and wetness episodes in the upper Nen River (UNR) basin have been analyzed for the period of 1951–2012 using meteorological drought indices and for the period of 1898–2010 using hydrological drought indices. There were three meteorological indices: one based on precipitation [the Standardized Precipitation Index (SPI)] and the other two based on water balance with different formulations of potential evapotranspiration (PET) in the Standardized Precipitation Evapotranspiration Index (SPEI). Moreover, two hydrological indices, the Standardized Runoff Index and Standardized Streamflow Index, were also applied in the UNR basin. Based on the meteorological indices, the results showed that the main dry period of 1965–1980 and wet periods of 1951–1964 and 1981–2002 affected this cold region. It was also found that most areas of the UNR basin experienced near normal condition during the period of 1951–2012. As a whole, the UNR basin mainly had the drought episodes in the decades of 1910, 1920, 1970 and 2000 based on hydrological indices. Also, the severity of droughts decreased from the periods of 1898–1950 to 1951–2010, while the severity of floods increased oppositely during the same periods. A correlation analysis showed that hydrological system needs a time lag of one or more months to respond to meteorological conditions in this cold region. It was also found that although precipitation had a major role in explaining temporal variability of drought, the influence of PET was not negligible. However, the sole temperature driver of PET had an opposite effect in the UNR basin (i.e., misestimating the drought detection) and was inferior to the SPI, which suggests that the PET in the SPEI should be determined by using underlying physical principles. This finding is an important implication for the drought research in future. 相似文献
14.
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
15.
Mitja Janža 《Natural Hazards》2013,67(3):1025-1043
According to climate change projections, the Alps will be one of the most affected regions in Europe. A basis for adaptation measures to climate changes is the quantification of the impact. This study investigates the impact of projected climate change on the hydrological cycle in the Upper So?a River basin. It is based on the use of climate model data as input for hydrological modelling. The climatic input data used were generated by a global climate model (IPCC A1B emission scenario) and downscaled for local use. Hydrological modelling was performed using the distributed hydrological model MIKE SHE. The simulated impact was quantified by comparing results of the hydrological modelling for the control period (1971–2000) and different scenario periods (2011–2040, 2041–2070, 2071–2100). The climate projections show an increase in the average temperature (+0.9, +2.3, +3.8°C) and negligible changes in average precipitation amounts in the scenario periods. More distinctive are changes in the temporal pattern of mean monthly values (up to +5.2°C and ±45% for precipitation), which result in warmer and wetter winters and hotter and drier summers in the scenario periods. The projected rise in temperature is reflected in the increased actual evapotranspiration, the reduction of snow amount and summer groundwater recharge. Changes of monthly and period average discharges follow the trends of the meteorological variables. Changes in precipitation patterns have a major influence on the projected hydrological cycle and are the most important source of uncertainty. Estimated extreme flows indicated increased hazards related to floods, especially in the near-future scenario period, while in the far future scenario period, distinctive drought conditions are projected. 相似文献
16.
The present study examined the influence of climate change on the spread of West Nile virus (WNV) in Canada among American crows (Corvus brachyrhynchos) by first identifying the significant climatic and environmental determinants of positive WNV cases in American crow specimens from 2009 to 2013. Using this information, we projected climate change scenarios on the potential spread of WNV in American crow species in Canada for three time periods: 2015–2039, 2040–2069, and 2070–2099. Using bird specimen, meteorological and land-use data, the statistical association between positive WNV cases in American crows and the environment was assessed by means of a general linear mixed model. Statistical results revealed that temperature and precipitation were significantly related to positive cases of WNV in American crows. Thus, climate change projections of summer mean temperature averages were projected for the three time periods. Climate change scenarios were created and imported into Quantum Geographic Information System (QGIS) and an algorithm was applied using the raster calculator to spatially delineate current and future areas of risk. Spatial analyses revealed that increased warming in the near future may increase the latitudinal extension of WNV in American crows in Canada. 相似文献
17.
K T SENZEBA S RAJKUMARI A BHADRA A BANDYOPADHYAY 《Journal of Earth System Science》2016,125(3):443-457
Snowmelt run-off model (SRM) based on degree-day approach has been employed to evaluate the change in snow-cover depletion and corresponding streamflow under different projected climatic scenarios for an eastern Himalayan catchment in India. Nuranang catchment located at Tawang district of Arunachal Pradesh with an area of 52 km2 is selected for the present study with an elevation range of 3143–4946 m above mean sea level. Satellite images from October to June of the selected hydrological year 2006–2007 were procured from National Remote Sensing Centre, Hyderabad. Snow cover mapping is done using NDSI method. Based on long term meteorological data, temperature and precipitation data of selected hydrological year are normalized to represent present climatic condition. The projected temperature and precipitation data are downloaded from NCAR’s GIS data portal for different emission scenarios (SRES), viz., A1B, A2, B1; and IPCC commitment (non-SRES) scenario for different future years (2020, 2030, 2040 and 2050). Projected temperature and precipitation data are obtained at desired location by spatially interpolating the gridded data and then by statistical downscaling using linear regression. Snow depletion curves for all projected scenarios are generated for the study area and compared with conventional depletion curve for present climatic condition. Changes in cumulative snowmelt depth for different future years are highest under A1B and lowest under IPCC commitment, whereas A2 and B1 values are in-between A1B and IPCC commitment. Percentage increase in streamflow for different future years follows almost the same trend as change in precipitation from present climate under all projected climatic scenarios. Hence, it was concluded that for small catchments having seasonal snow cover, the total streamflow under projected climatic scenarios in future years will be primarily governed by the change in precipitation and not by change in snowmelt depth. Advancing of depletion curves for different future years are highest under A1B and lowest under IPCC commitment. A2 and B1 values are in-between A1B and IPCC commitment. 相似文献
18.
Drought is one of the most detrimental natural disasters. Studying the changing characteristics of drought is obviously of great importance to achieve the sustainable use of water resources at river basin scales. In this paper, the satellite-based Vegetation Condition Index (VCI) and Vegetation Health Index (VH) were firstly calculated by using NDVI and brightness of the Global Vegetation Index dataset derived from Advance Very High Resolution Radiometer for China in growing seasons over 1982–2005. Then, the long-term VCI and VH data were employed to study the variation of droughts in the ten basins covering the whole country. The linear trend of each pixel showed that most parts of China were getting wetter in growing seasons, and the drought areas defined by the number of drought pixels have decreased in most basins. The increasing trend of basin averaged values of VCI and VH also indicates the whole country was generally getting wetter. At last, to better understand the two remote sensing drought indices, the response of the growing-season VCI and VH was compared to that of the Palmer Drought Severity Index and 6-month Standard Precipitation Index. Significant spatial variability of the relationship between the VCI, VH, and the station-based meteorological drought indices was shown, and some more closely related areas were found. The study will be useful for water resources management for each basin in the future. 相似文献