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1.
新疆阿尔泰山地区极端水文事件对气候变化的响应 总被引：3，自引：2，他引：1
新疆北部阿尔泰山地区受西风带气流影响, 降水丰沛, 尤其冬季积雪厚而稳定, 山区产流发育了额尔齐斯河与乌伦古河, 从西到东形成主要支流十余条. 在全球气候变化下, 山区气温上升明显, 极端降水增多, 气候变暖带来的水循环加快, 极端水文事件也趋于增多. 由于冬季气温升高, 春季积雪消融提前, 春季融雪洪水提前, 洪峰流量增强; 夏季极端降水增加, 使得暴雨洪水增多. 由于冬、 春季积雪增多, 雪灾发生频率增加, 春季的融雪洪水灾害危害增强. 极端水文事件引起的自然灾害已经威胁到阿勒泰地区的牧业生产、 交通安全和水资源供给, 应加强水文水资源安全对气候变化的应对措施, 提高水资源安全保障, 减缓气候变化的危害. 相似文献
2.
We examined spatial distribution characteristics of extreme hydrological events in Xinjiang, China, using district data from 1901 to 2010. Frequency distribution showed a general symmetry along the Tianshan Mountains, with even distribution in Junggar Basin and Tarim Basin. Frequency was more in the north-west than in the south-east. The maximum incidence was in west Tianshan Mountains and generally decreased south-eastward. There were significant regional variations in type distribution. Rainstorm floods were more common in central Xinjiang. Hailstorms mainly occurred in the central Junggar Basin, the southern slope of the western Tianshan Mountains and north-west of Tarim Basin. Debris flow was mainly distributed in Ili Valley and the central northern Tianshan Mountains. Glacier lake outburst floods were more common in the Karakorum Mountains and southern slopes of the western Tianshan Mountains. Ice floods were mainly distributed in the western Tianshan Mountains. Snow hazards were mainly distributed in the wide northern areas, especially the Altai Mountains and Hamilton Basin. Snowmelt floods were mainly distributed in the Tacheng Basin and Ili Valley. The incidence of extreme hydrological events was greatly affected by weather systems and terrain features. 相似文献
3.
基于1961 - 2017年6 - 8月新疆北部47个观测站点的逐日降水资料, 根据百分位法定义不同站点的夏季极端降水阈值, 分析了新疆北部地区夏季极端降水事件和最大日降水的时空分布特征、 贡献率及其与海拔的关系。结果表明： 新疆北部地区夏季极端降水事件和最大日降水量的各个特征量分布存在明显的时空差异, 空间上夏季极端降水事件、 最大日降水量表现为山区高、 盆地低的特点,在海拔2 000 m左右存在一个最大降水带; 夏季极端降水事件和最大日降水量呈增多、 增强的趋势, 并从20世纪90年代前后开始有明显的增加。夏季极端降水事件主要以单日为主, 夏季极端降水贡献随时间呈缓慢增加的趋势, 而夏季极端降水过程贡献和最大日降水贡献随时间变化呈下降趋势。 相似文献
4.
新疆阿勒泰地区近50 a夏季极端降水事件变化特征 总被引：3，自引：2，他引：1
利用新疆阿勒泰地区近50 a(1961-2010年)7站夏季(6-8月)逐日降水资料、NCEP/NCAR资料及大气环流指数,采用百分位定义法确定各站夏季极端降水事件阈值,运用线性趋势、突变分析、滑动t检验、Morlet小波分析及相关分析等方法来分析该地区夏季极端降水事件的气候变化.研究表明:阿勒泰地区各站夏季极端降水事件阈值为9.0~13.1 mm·d-1,阈值存在明显的空间分布差异,且地形及海拔高度对该地区夏季极端降水事件阈值均有影响,海拔高度与阈值两者基本呈指数关系.近50 a来阿勒泰地区夏季极端降水频数及强度的年代际变化具有较好的同步性,均表现为20世纪80年代中期之前频数(强度)偏少(弱),80年代中期以后频数(强度)增多(增强),并于20世纪90年代中期达到最多(最强),但进入2000年后频数(强度)开始减少(减弱).近50 a来阿勒泰地区夏季极端降水事件年际变化的持续性较好,大部分站均没有出现显著性突变,只有阿勒泰、富蕴站在20世纪80年代末期及90年代初出现了明显的突变.北非大西洋北美副高脊线、北非副高脊线、西藏高原A指数是影响该地区夏季极端降水事件的主要因子. 相似文献
5.
新疆阿尔泰山区克兰河上游水文过程对气候变暖的响应 总被引：17，自引：7，他引：10
额尔齐斯河支流克兰河上游发源于西风带水汽影响的阿尔泰山南坡,主要由融雪径流补给,年内积雪融水可占年径流量的45%.年最大月径流一般出现在6月份,融雪季节4~6月径流量占65%.流域自20世纪60年代开始明显升温,年平均温度从50年代的1.4℃上升到90年代的5.2℃;年降水总量也呈增加趋势,尤其是冬季和初春增加最多.随着气候变暖,河流年内水文过程发生了很大的变化,主要表现在最大月径流由6月提前到5月,月径流总量增加约15%,4~6月融雪径流量也由占年流量的60%增加到近70%.在多年变化趋势上,气温上升主要发生在冬季,降水也以冬季增加明显,而夏季降水呈下降趋势;水文过程主要表现在5月径流呈增加趋势,而6月径流为下降趋势;夏季径流减少而春季径流增加明显.冬春季积雪增加和气温上升,导致融雪洪水增多且洪峰流量增大,使洪水灾害破坏性加大.近些年来气候变暖引起的年内水文过程变化,已经对河流下游的城市供水和农牧业生产产生了影响. 相似文献
6.
1961-2010年西北干旱区极端降水指数的时空变化分析 总被引：3，自引：0，他引：3
结合绝对阈值和百分位法定义极端降水事件的优点,提出了一种更灵敏的检测极端降水事件的方法. 该方法不仅能检测出常用降水指数无法检测到的降水量稀少地区尤其干旱区的极端降水事件,同时也能过滤掉其检测到的降水量丰富地区的虚假极端降水事件. 此方法首次被应用于统计1961年1月至2010年2月西北干旱区72个气象站点的年和季节的极端降水指数（大降水和强降水指数）,并分析了极端降水指数的时间变化趋势及其空间分布特征. 结果表明：西北干旱区春（3-5月）、秋（9-11月）、冬（12月至次年2月）三季极端降水指数无显著（P>0.05）变化趋势,夏季（6-8月）大降水的频率和降水量以及大降水降水量占总降水量的比重都显著增加;新疆地区极端降水指数为增加趋势的区域基本都分布在海拔较高（约海拔1 000 m以上）的地区;西北干旱区东部极端降水指数变化趋势的空间分布有明显的季节差异,表现为夏、秋季大部分地区为增加趋势,冬、春季大部分地区为减小趋势. 相似文献
7.
Evaluation of CHIRPS and its application for drought monitoring over the Haihe River Basin,China 总被引：2，自引：0，他引：2
Feng Gao Yuhu Zhang Xiulin Ren Yunjun Yao Zengchao Hao Wanyuan Cai 《Natural Hazards》2018,91(1):155-178
To establish the drought index objectively and reasonably and evaluate the hydrological drought accurately, firstly, the optimal distribution was selected from nine distributions (normal, lognormal, exponential, gamma, general extreme value, inverse Gaussian, logistic, log-logistic and Weibull), then the Optimal Standardized Streamflow Index (OSSI) was calculated based on the optimal distribution, and last, the spatiotemporal evolution of hydrological drought based on the OSSI series was investigated through the monthly streamflow data of seven hydrological stations during the period 1961–2011 in Luanhe River basin, China. Results suggest: (1) the general extreme value and log-logistic distributions performed prominently in fitting the monthly streamflow of Luanhe River basin. (2) The main periods of hydrological drought in Luanhe River basin were 148–169, 75–80, 42–45, 14–19 and 8–9 months. (3) The hydrological drought had an aggravating trend over the past 51 year and with the increase in timescale, the aggravating trend was more serious. (4) The lower the drought grade was, the broader the coverage area. As for the Luanhe River basin, the whole basin suffered the mild and more serious drought, while the severe and more serious drought only cover some areas. (5) With the increase in time step, the frequency distribution of mild droughts across the basin tended to be concentrated, the frequency of extreme droughts in middle and upper reaches tended to increase and the frequency in downstream tends to decrease. This research can provide powerful references for water resources planning and management and drought mitigation. 相似文献
8.
Under the current condition of climate change, droughts and floods occur more frequently, and events in which flooding occurs after a prolonged drought or a drought occurs after an extreme flood may have a more severe impact on natural systems and human lives. This challenges the traditional approach wherein droughts and floods are considered separately, which may largely underestimate the risk of the disasters. In our study, the sudden alternation of droughts and flood events (ADFEs) between adjacent seasons is studied using the multivariate L-moments theory and the bivariate copula functions in the Huai River Basin (HRB) of China with monthly streamflow data at 32 hydrological stations from 1956 to 2012. The dry and wet conditions are characterized by the standardized streamflow index (SSI) at a 3-month time scale. The results show that: (1) The summer streamflow makes the largest contribution to the annual streamflow, followed by the autumn streamflow and spring streamflow. (2) The entire study area can be divided into five homogeneous sub-regions using the multivariate regional homogeneity test. The generalized logistic distribution (GLO) and log-normal distribution (LN3) are acceptable to be the optimal marginal distributions under most conditions, and the Frank copula is more appropriate for spring-summer and summer-autumn SSI series. Continuous flood events dominate at most sites both in spring-summer and summer-autumn (with an average frequency of 13.78% and 17.06%, respectively), while continuous drought events come second (with an average frequency of 11.27% and 13.79%, respectively). Moreover, seasonal ADFEs most probably occurred near the mainstream of HRB, and drought and flood events are more likely to occur in summer-autumn than in spring-summer. 相似文献
9.
使用2009年DOY (Day of Year) 145~288时段与2001~2010年夏季(DOY 161~240时段)的Terra/MODIS 16 d合成的植被指数产品数据MOD13 A2和8 d合成的地表温度(Land Surface Temperature,TLS)产品数据MOD11 A2,构建TLS~IEV(Enhanced Vegetation Index,IEV)特征空间,从而得到了条件温度植被干旱指数(Temperature Vegetation Drought Index,ITVD)反映的藏北土壤湿度空间分布。对藏北高原2009年植被生长季内土壤湿度的季节性变化及2001~2010年夏季土壤湿度的年际变化特征进行分析,研究结论表明:随着植被盖度的增大,干、湿边斜率逐渐变小,植被对环境温度的变化具有缓冲效应;藏北高原土壤湿度的季节性变化明显,主要受温度、降水、植被覆盖和冻土过程等季节性变化的影响;近10年研究区内土壤湿度有轻微的旱化趋势,但不同气候区内的年际变化表现不一致;气温表现不同程度的显著升温趋势,部分站点的降水有不显著减少趋势,其它站点降水表现为年际波动,而区域统计的ITVD值年际波动与站点气温的变化大体一致。 相似文献
10.
天山南坡黄水沟与清水河寒区流域极端水文事件对气候变化的响应 总被引：1，自引：0，他引：1
冰川、积雪和冻土变化产生的水文效应对下游水资源供给具有重要影响,近几十年来新疆区域洪水呈显著加重趋势,尤其是南疆区域洪水明显加剧. 以天山南坡黄水沟与清水河寒区流域为研究区域,通过分析水文站极端水文事件,结合流域上游山区巴伦台气象站资料,研究了高寒山地流域在气候变化背景下极端水文过程出现时间、年最大和最小径流的响应特征. 结果表明：1986年是水文过程的突变点,从1986年开始随着降水、气温的增加,河流径流量呈增加趋势;最大年径流出现时间从6月中下旬推迟到7月下旬;最大径流和最小径流与年径流量呈正相关关系,最大径流与夏季降水关系密切,而最小年径流与冬春季的气温关系密切. 随着1986年以来的气温升高,冻土退化产生的水文效应使冬季径流增加明显,也使年最小径流明显增大;1986年以来降水变化决定着年径流量增加,使年最大径流集中出现在夏季且量级增大. 总体来讲,20世纪80年代中期以后山区河流年极端洪峰量增大,洪水量增多,年际间变化幅度明显增大,从而对下游造成更严重的灾害. 因此,加强气候变化对寒区流域水资源和洪水灾害的影响评估,使科学技术在减灾方面发挥主导作用. 相似文献
11.
新疆气候水文变化趋势及面临问题思考 总被引：2，自引：0，他引：2
新疆是亚洲中部干旱区的重要组成部分, 对全球变化响应异常敏感, 水资源问题突出, 研究变暖背景下新疆的气候水文变化及面临的问题, 对应对和适应未来气候变化及水资源安全具有重要意义。基于最新的气候水文观测资料和相关成果, 研究了新疆水文气候要素变化趋势与演变特征, 探讨了目前面临的主要问题及对策建议。结果表明： 1961—2018年新疆升温幅度高于全球平均水平, 冬季升温贡献最大; 降水量和降水日数均明显增加, 夏季降水增加最显著; 21世纪以来气温和降水均在高位波动, 但增加幅度减缓, 气候有从暖湿化向暖干化转折的迹象, 干旱化趋势加剧。21世纪以来, 极端最高气温、 极端最低气温和高温日数显著增加, 高温初日提前, 高温终日推迟, 极端降水事件、 暴雨雪强度和频次明显增加。受气候变化和人类活动共同影响, 塔里木河流域源流区径流量明显增加, 干流径流量微弱减少; 博斯腾湖水位阶段性变化明显, 2013年以来逐渐扩张; 艾比湖总体萎缩, 而山区湖泊赛里木湖面积稳定扩张。新疆气候水文变化面临主要问题包括： 对新疆气候变化趋势和物理过程认识不明、 水文气象灾害风险加剧难以把控、 气候变化影响不确定性加剧, 水安全问题迫在眉睫。建议趋利避害, 抓住气候机遇, 加快生态环境建设; 开展气候水文综合科学考察, 加强机理研究, 构建综合观测协同网络, 提高水文气象灾害风险调控能力; 将有效应对、 有序适应气候变化提升到战略的高度, 为建设美丽新疆和高质量发展服务。 相似文献
12.
Mohsen Tavakoli Florimond De Smedt Thomas Vansteenkiste Patrick Willems 《Natural Hazards》2014,71(3):2127-2142
This study investigates how extreme flows in the Grote Nete watershed located in the Flanders region of Belgium will respond to climate change and urban growth using the hydrological model WetSpa. Three climate change scenarios (low, mean and high), three urban development scenarios (low, medium and high) and the nine combined climate–urban change scenarios are considered. The results indicate that extreme low flows would decrease noticeably by climate change, while they would be less sensitive to urban development. On the other hand, extreme peak flows are predicted to increase considerably due to both climate change and urban growth. It is concluded that coupling the effects of land use change with climate change may lead to severe increase in the frequency river floods in winter as well as the frequency of extreme river low flows in summer. 相似文献
13.
Spatiotemporal changes of global extreme temperature events (ETEs) since 1981 and the meteorological causes 总被引：2，自引：0，他引：2
Xiao Song Zhao Zhang Yi Chen Pin Wang Ming Xiang Peijun Shi Fulu Tao 《Natural Hazards》2014,70(2):975-994
Of the various types of disasters caused by extreme climate and weather, extreme temperature events (ETEs) have led to a heightened awareness due to their increasing frequency, intensity, widespread distribution, and severe health impacts. Although many previous studies have surveyed the severe impacts of specific ETEs, few systematic studies have analyzed the temporal trends and the spatial patterns of this type of ETEs at the global scale. In the present study, disaster data from 1981 to 2010 compiled by Emergency Events Database were used to obtain a global view of the distribution of and the changes in the recorded ETEs. In addition, the daily maximum/minimum temperature data provided by National Centers for Environmental Prediction /Department of Energy Reanalysis 2 were used to explore the potential meteorological causes of these events. The results showed 2.7 and 6.4 increases in the frequencies of heat waves and cold spells per decade, respectively, since the 1980s. However, a large regional variability was found worldwide. Moreover, more than 40 % of the recorded ETEs occurred in Europe, and Asia experienced 33 and 26 % of the heat wave and cold spell events, respectively. Additionally, the global pattern for the occurrence frequency of ETEs in recent decades could be largely ascribed to the meteorological indexes: the heat stress index (HSI) and the cold stress index (CSI). The frequency of heat wave events increased from 1981 to 2010, and this trend is consistent with the increase in the HSI. However, the cold spell events did not appear to be reduced, as demonstrated by the disaster records, and this finding is inconsistent with the CSI trend. This result indicates that other factors also influence the occurrence of disaster events. 相似文献
14.
选取1955-2017年新疆因雪灾造成的牲畜受灾数量、作物受灾面积、经济损失三大灾情数据,揭示新疆雪灾时间和空间分布特征,通过构建雪灾灾损指数,对新疆雪灾进行区划。分析表明：新疆雪灾的发生北疆多于南疆,山区多于盆地,西部多于东部,主要集中发生在阿尔泰山区、天山山区及昆仑山区,灾情最重的是阿勒泰地区、伊犁地区、塔城地区;进入2000年以后,雪灾呈现明显高位震荡特点;利用多指标综合评估法,运用连续型随机变量分布密度近似求法,求得的新疆雪灾灾损指数,能客观反映新疆雪灾灾情;雪灾灾损指数遵从Γ分布,根据Γ分布函数属性及各类雪灾事件发生概率,进行了新疆雪灾等级区划。研究成果可为决策服务及气候可行性论证提供理论依据,对科学准确地制定防灾备灾措施、及时组织开展雪灾应急救助工作以及灾后的恢复重建决策给予一定参考。 相似文献
15.
气候的舒适度是游客选择旅游目的地的重要影响因素之一,利用1960-2013年近54 a的研究区气象统计资料,结合地理信息系统(GIS)空间分析方法,并考虑气温垂直递减规律这一因素,分析了阿勒泰地区500 m×500 m分辨率栅格尺度的逐月温湿指数、风效指数、着衣指数及综合舒适指数,通过对4个指数所反映的舒适度和舒适期进行对比分析,发现综合舒适指数可从客观角度反映气候因素对人体感觉的综合影响,能达到较为精准的评估效果.研究表明:阿勒泰旅游气候舒适度变化受当地地形和季节变化的影响较大,旅游舒适度季节变化明显,适宜户外旅游的舒适期短暂.季节变化中,冬季不适宜开展户外旅游活动;春季阿尔泰山山区气候舒适度不舒适,山区以南和西南萨吾尔山以北舒适度较不舒适;夏季分布在额尔齐斯河以北的山麓和山间河谷地区,以及青河县中部和南部,富蕴县南部地区人体感觉舒适,占全区总面积的39.62%,其余大部分区域较舒适;秋季分布在哈巴河县、布尔津县、阿勒泰市南部及福海县中部和南部区域感觉较舒适,占全区总面积的36.79%.阿勒泰地区旅游舒适期为1~5个月,旅游资源的空间分布契合该地区旅游舒适期的区域空间分布,利于本地区进行旅游开发和旅游活动. 相似文献
16.
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
17.
1961-2014年新疆冰雹灾害时空分布特征 总被引：2，自引：0，他引：2
通过整理、 普查得到1961-2014年新疆以县为单位的雹灾频次、 受灾面积、 经济损失的样本序列, 在此基础上定义了表征雹灾程度的无量纲数损失指数. 结果表明: 新疆雹灾频次集中出现在阿克苏地区、 博州、 石河子地区, 5-8月为多发期, 6月最多. 雹灾的年际变化呈现出2～5 a的短周期和7～8 a的长周期, 20世纪60、 70年代为新疆雹灾的少发期, 1980-1994年、 2001-2014年为雹灾的两个集中高发期. 按照地区累计灾损指数将新疆雹灾划分为5个等级, 阿克苏地区属严重雹灾区, 喀什地区、 塔城地区、 伊犁州属重雹灾区, 石河子地区、 博州、 昌吉州、 巴州、 克拉玛依市属中雹灾区, 阿勒泰地区、 克州、 和田地区、 哈密地区属轻雹灾区, 吐鲁番地区和乌鲁木齐市属微雹灾区. 相似文献
18.
Droughts in the southeast USA have been linked to economic losses and intractable water conflicts. The region has witnessed several severe droughts events during the period from 1901 to 2005. In this study, spatiotemporal variability in meteorological drought characteristics in the southeast were analyzed using two different datasets by the means of standard precipitation index and standard precipitation evapotranspiration index for the period 1901–2005 for agricultural and non-agricultural seasons. The study periods were divided into three epochs 1901–1935, 1936–1970, and 1971–2005 and drought characteristics, in terms of severity, frequency, number, and trends were analyzed. Additionally, areal extent, drought severities and return periods associated with three severe drought years 1904, 1954, and 2000 were analyzed. Except for the state of Florida, results indicate decrease in drought severity during the recent epoch of 1970–2005 in the study domain. Trend analysis confirms that the study domain has become wetter over the last 105 years. Wetting trends were more prominent in the agricultural season. Additionally, droughts seem to have migrated from the western part of the study area encompassing the states of Alabama, Tennessee, Louisiana, and Mississippi to the Florida panhandle region during the recent epoch. Droughts exhibited higher spatiotemporal variability during the agricultural season compared to the non-agricultural seasons. Results also showed that early to mid-1950s experienced some of the most severe droughts in the study domain. Some of the drought events, such as the drought of 1954 and 2000, have been equivalent to a 100-year drought event in the southeast. The results from this study form the benchmark for studying the impacts of future climate change projections on meteorological droughts in the southeast. 相似文献
19.
春季热带海温与北疆夏季极端降水的关系研究 总被引：1，自引：0，他引：1
基于1961—2017年北疆47站夏季逐日降水资料、NOAA海温资料和NCEP/NCAR再分析资料,利用90%分位确定北疆夏季单站降水阈值,得出极端降水量,讨论了春季热带海温与北疆夏季极端降水的关系。结果表明：北疆夏季极端降水和春季热带印度洋（20° S~15° N,50°~110° E）及赤道东太平洋（15° S~15° N,90°~180° W）海温呈正相关,两个关键区春季热带海温异常偏暖时,北疆夏季极端降水偏多,仅春季热带印度洋关键区海温异常偏暖时,北疆西北地区夏季极端降水偏多。当春季热带印度洋和赤道东太平洋关键区海温同时异常偏暖时,200 hPa西风急流轴明显偏南,500 hPa西西伯利亚和中亚地区低值系统活跃,南方路径输送的水汽增加,有利于北疆夏季极端降水的发生;仅春季热带印度洋关键区海温异常偏暖时,200 hPa西风急流强度增强,500 hPa西西伯利亚地区低值系统活跃,配合偏东路径的水汽输送,北疆西北地区夏季极端降水偏多。 相似文献
20.
使用1951-2004年中国738个测站逐日降水资料,采用百分位的方法定义极端降水事件的阈值,分析了不同持续时间的极端降水事件的时空分布及变化趋势特征。结果表明,极端降水事件多发于35°N以南,特别是在长江中下游和江南地区以及高原东南部,且在这些地区极端降水事件持续时间也较长。季节分布上,主要出现在夏季,以低持续性事件为主。在中国东部地区,持续时间越长的极端降水其强度往往越强。趋势分析表明,全国持续1d极端事件的相对频数具有上升趋势而平均强度具有下降趋势,其空间上均表现为全国大部分上升、华北和西南等地下降的趋势。持续2d以上极端事件在长江中下游流域、江南地区和高原东部等地区有显著增多和增强的趋势,而在华北和西南地区有减少和减弱趋势,但全国平均的趋势不显著。 相似文献