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1.
基于黄河上、中和下游的径流及气候资料，对径流的年代际变化规律及与气候变化的关系进行了分析.结果表明：黄河流域的径流均存在显著的年代际变化趋势，径流的显著特征是从20世纪80年代开始的减少趋势，但并未达到历史的最低，径流减少的趋势在下游比上游更显著，而这种变化趋势与流域的气候变化趋势基本一致，说明在年代际尺度上，径流的变化主要受气候的控制；在不同季节，这种关系有明显差异，如在冬季两者的变化趋势有较大差异.分析还发现，近年来流域地表的干化是流域径流减少的原因，气温的升高更加剧了流域地表干化. 相似文献
2.
根据1975年地形图、1970s末至2013年19期Landsat（MSS、TM、ETM+）陆地资源卫星和20032009年ICESat卫星数据,以及近40年气象资料,对西藏佩枯错湖泊面积变化进行分析.结果表明,湖泊面积、湖泊高度变化波动较大,均呈减少和退缩趋势.19752013年间湖泊面积减少10.68 km2,减幅为3.79%.从空间动态变化来看,变化较明显的区域位于该湖的南岸和东北岸,南岸、东北岸湖岸线分别向北、向西南萎缩.20032009年湖面高度和湖泊面积均呈现出下降趋势,分别下降了0.17 m和4.4 km2.19992013年之间对该流域湖泊有影响的冰川变化分析显示,冰川呈现出退缩、面积减少趋势.数据显示冰川面积总共减少了17.17 km2,减少率为7.91%.自1971年以来,流域气温总体呈上升趋势,2000年以后升温显著.佩枯错43 a来降水量年际变化波动较大,年降水量呈减少趋势,总的来说降水量每10 a减少6.99 mm.虽然佩枯错属于降水和冰雪融水补给湖泊,但该流域湖面增减与周围冰川变化的关系并不明显,与温度变化呈负相关,而与流域内降水量呈正相关.综合分析表明,佩枯错流域湖泊变化与冰川退缩关系不密切,降水量是湖泊变化的主要原因. 相似文献
3.
Qiang Zhang Chong-Yu Xu Zengxin Zhang Yongqin David Chen Chun-ling Liu Hui Lin 《Journal of Hydrology》2008,353(3-4):215-227
This study investigated spatial and temporal patterns of trends of the precipitation maxima (defined as the annual/seasonal maximum precipitation) in the Yangtze River basin for 1960–2005 using Mann–Kendall trend test, and explored association of changing patterns of the precipitation maxima with large-scale circulation using NCEP/NCAR reanalysis data. The research results indicate changes of precipitation maxima from relative stable patterns to the significant increasing/decreasing trend in the middle 1970s. With respect to annual variability, the rainy days are decreasing and precipitation intensity is increasing, and significant increasing trend of precipitation intensity was detected in the middle and lower Yangtze River basin. Number of rain days with daily precipitation exceeding 95th and 99th percentiles and related precipitation intensities are in increasing tendency in summer. Large-scale atmospheric circulation analysis indicates decreasing strength of East Asian summer monsoon during 1975–2005 as compared to that during 1961–1974 and increasing geopotential height in the north China, South China Sea and west Pacific regions, all of which combine to negatively impact the northward propagation of the vapor flux. This circulation pattern will be beneficial for the longer stay of the Meiyu front in the Yangtze River basin, leading to more precipitation in the middle and lower Yangtze River basin in summer months. The significant increasing summer precipitation intensity and changing frequency in the rain/no-rain days in the middle and lower Yangtze River basin have potential to result in higher occurrence probability of flood and drought hazards in the region. 相似文献
4.
Feifei Yuan Hiroshi Yasuda Ronny Berndtsson Cintia Bertacchi Uvo Linus Zhang Zhenchun Hao 《水文科学杂志》2013,58(8):1383-1394
ABSTRACTThe summer precipitation (June–September) in the source region of the Yellow River accounts for about 70% of the annual total, playing an important role in water availability. This study divided the source region of the Yellow River into homogeneous zones based on precipitation variability using cluster analysis. Summer precipitation trends and teleconnections with global sea-surface temperatures (SST) and the Southern Oscillation Index (SOI) from 1961 to 2010 were investigated by Mann-Kendall test and Pearson product-moment correlation analysis. The results show that the northwest part (Zone 1) had a non-significantly increasing trend, and the middle and southeast parts (zones 2 and 3) that receive the most precipitation displayed a statistically significant decreasing trend for summer precipitation. The summer precipitation in the whole region showed statistically significant negative correlations with the central Pacific SST for 0–4 month lag and with the Southern Indian and Atlantic oceans SST for 5–8 month lag. Analyses of sub-regions reveal intricate and complex correlations with different SST areas that further explain the summer precipitation variability. The SOI had significant positive correlations, mainly for 0–2 months lag, with summer precipitation in the source region of the Yellow River. It is seen that El Niño Southern Oscillation (ENSO) events have an influence on summer precipitation, and the predominant negative correlations indicate that higher SST in equatorial Pacific areas corresponding to El Niño coincides with less summer precipitation in the source region of the Yellow River.
Editor Z.W. Kundzewicz; Associate editor D. Gerten 相似文献
5.
There has been increasing attention over the last decade to the potential effects of glacier retreat on downstream discharge and aquatic habitat. This study focused on streamflow variability downstream of Bridge Glacier in the southern Coast Mountains of BC between 1979 and 2014, prior to and during a period in which the glacier experienced enhanced calving and rapid retreat across a lake‐filled basin. Here we combined empirical trend detection and a conceptual‐parametric hydrological model to address the following hypotheses: (1) streamflow trends in late summer and early autumn should reflect the opposing influences of climatic warming (which would tend to increase unit‐area meltwater production) and the reduction in glacier area (which would tend to reduce the total volume of meltwater generated), and (2) winter streamflow should increase because of displacement of lake water as ice flows past the grounding line and calves into the lake basin. In relation to the first hypothesis, we found no significant trends in monthly discharge during summer. However, applying regression analysis to account for air temperature and precipitation variations, weak but statistically significant negative trends were detected for August and melt season discharge. The HBV‐EC model was applied using time‐varying glacier cover, as derived from Landsat imagery. Relative to simulations based on constant glacier extent, model results indicated that glacier recession caused a decline in mean monthly streamflow of 9% in August and 11% in September. These declines in late‐summer streamflow are consistent with the results from our empirical analysis. The second hypothesis is supported by the finding of positive trends for December, January, and February discharge. Despite the modelled declines in late‐summer mean monthly streamflow, recorded discharge data exhibited neither positive nor negative trends during the melt season, suggesting that Bridge Glacier may currently be at or close to the point of peak water. Further analysis of the impact of lake‐terminating glaciers on downstream discharge is needed to refine the peak water model. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
6.
The Bhagirathi River, a proglacial melt water stream of the Gangotri Glacier, is the principal source of the Ganges river system. The upper part of the basin lies in the high altitude region of the Garhwal Himalayas and is extensively covered by glaciers. We provide hydro‐meteorological insight into a severe storm that produced unusual high rains in June 2000 in the uppermost part of the Bhagirathi River. This storm was concentrated upstream of Gangotri town and triggered landslides/rockslides at several locations between the glacier snout and Gangotri town. One of the major rockslides blocked the Bhagirathi River at Bhujbas, about 3 km downstream of the Gangotri Glacier snout, creating an artificial lake at this location. High stream flow in the river, generated by rapid runoff response from mountain slopes along with melt runoff from the glacier, quickly increased the level of water stored in the artificial lake. Daily rainfall in this region rarely exceeds 10 mm, while total rainfall during this 6‐day storm was 131·5 mm. This unusual rain event occurred during the tourist season in June, consequently trapping a large number of tourists and vendors in this area. Sudden release of stored water generated floods that created havoc downstream of the artificially created lake. This paper presents the hydrological and meteorological information related to such an unusual and devastating event observed in the high altitude region of the Himalayas. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
7.
Hydroclimatology of the Upper Madeira River basin: spatio-temporal variability and trends 总被引：1，自引：0，他引：1
Jorge Molina-Carpio Jhan Carlo Espinoza Philippe Vauchel Josyane Ronchail Beatriz Gutierrez Caloir Jean-Loup Guyot 《水文科学杂志》2017,62(6):911-927
Rising in the Andes, the Madeira River drains the southwestern part of the Amazon basin, which is characterized by high geographical, biological and climatic diversity. This study uses daily records to assess the spatio-temporal runoff variability in the Madeira sub-basins. Results show that inter-annual variability of both discharge and rainfall differs between Andean and lowland tributaries. High-flow discharge variability in the Andean tributaries and the Guaporé River is mostly related to sea surface temperature (SST) in the equatorial Pacific in austral summer, while tropical North Atlantic (TNA) SST modulates rainfall and discharge variability in the lowlands. There also is a downward trend in the low-flow discharge of the lowland tributaries which is not observed in the Andes. Because low-flow discharge values at most lowland stations are negatively related to the SST in the tropical North Atlantic, these trends could be explained by the warming of this ocean since the 1970s.
EDITOR A. CastellarinASSOCIATE EDITOR A. Viglione 相似文献
8.
Precipitation change and human impacts on hydrologic variables in Zhengshui River Basin, China 总被引：4，自引：3，他引：1
Juan Du Fei He Zhao Zhang Peijun Shi 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(7):1013-1025
Climate change and anthropogenic impacts on hydrologic variables have received significant attention in recent years. We assessed
stream flow and water level in the Zhengshui River basin, China, in the period 1960 to 2003 in response to precipitation variation
and anthropogenic factors. Analyses of daily discharge and water level records, and derived annual, seasonal and monthly series,
showed that Zhengshui River flows had a significant increasing trend, with an abrupt change point in 1990. There was a significant
decreasing water level trend with an abrupt change point in 1995. Human activities and precipitation contributed 53 and 47%,
respectively, to increase in stream flow during 1991–2003. Anthropogenic activities such as sand dredging, dominated the decrease
in water level during 1994–2003. Human-induced land use change, soil erosion and sand excavation driven by rapid economic
development have played a more important role than precipitation variation in hydrological changes in the Zhengshui River
basin over the past 50 years. 相似文献
9.
Plausible impact of global climate change on water resources in the Tarim River Basin 总被引：35，自引：1，他引：34
CHEN Yaning & XU Zongxue Xinjiang Institute of Ecology & Geography Chinese Academy of Sciences Urumqi China College of Environmental Sciences Beijing Normal University Beijing China 《中国科学D辑(英文版)》2005,48(1):65-73
Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and stream-flow was detected, and the possible association between the El Nino/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1℃rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the 1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and 相似文献
10.
洪泽湖是淮河水系中最重要的湖泊之一,是我国的第四大淡水湖,它在防洪、灌溉、航运、跨流域调水以及水资源与水环境保护等方面发挥着重要作用.过去300年来,由于黄淮关系的演变和人类活动的影响,洪泽湖水域面积发生剧烈变化.研究湖泊水域空间变化有助于认识流域环境变化与人类活动影响.本文利用18世纪初以来的古地图、历史文献资料及1981-2016年期间的7期遥感影像数据,采用遥感和地理信息系统技术相结合的方法,分析了近300年来洪泽湖水域时空演变过程及其原因.研究结果表明：过去300年来,洪泽湖面积总体呈减少趋势,年际缩减速率为0.17%,且湖域范围总体表现为由四周向中心缩小的趋势,其中西南湖域的形态变化最为显著.具体而言,清中期以前,黄河多次夺泗入淮,洪泽湖面积变化受黄淮关系、高家堰等水利枢纽的修建以及降水等因素影响.至清末,洪泽湖面积由3078.78 km2下降至2335.73 km2,共减少743.05 km2,其空间形态也发生了剧烈变化,该时期黄河改道、降水以及人口增长导致的湖滨围垦是影响洪泽湖演变的主要原因.建国以来（1949-2016年）,洪泽湖面积进一步缩小,由1757.60 km2下降至1488.43 km2,共减少了269.17 km2,其中1995-2000年间湖泊面积下降最为显著,共减少了281.43 km2,湖泊动态变化度达到2.78%,该时期自然因素对湖泊水域面积的影响减弱,而人口增长、围垦及水利工程的修建等人类活动逐渐成为影响洪泽湖演化的主导因素. 相似文献
11.
利用M-K相关分析方法和大通站1950-2000年逐月径流资料,研究了长江下游干流径流的趋势变化.研究结果表明:1950s以来长江下游径流量呈增加趋势,1990s平均径流量(30415.3 m3/s)比所有其他年代平均径流都大,为近50a以来的最大值;就季节和月份而言,秋季径流明显减少;夏、冬两季径流量,增加的趋势明显,尤以冬季枯水季节径流增加最为突出.洪水、枯水季节径流增加明显,但以枯水季节径流增加占优势.冬季枯水径流的增加,可能在一定程度上能够缓解长江口生态环境的巨大压力.1990s径流量的增加与全球变暖、水循环加快、长江流域降水量增加密切相关. 相似文献
12.
13.
Spatial and temporal patterns of stable water isotopes along the Yangtze River during two drought years 
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下载免费PDF全文 Changes in the level of the Yangtze River caused by anthropogenic water regulation have major effects on the hydrological processes and water cycle in surrounding lakes and rivers. In this study, we obtained isotopic evidence of changes in the water cycle of Yangtze River during the two drought years of 2006 and 2013. Isotopic evidence demonstrated that the δ18O and δD levels in Yangtze River exhibited high spatial heterogeneity from the upper to lower reaches, which were controlled by atmospheric precipitation, tributary/lake water mixing, damming regulation, and water temperature. Both the slope and intercept of Yangtze River evaporative line (δD = 7.88 δ18O + 7.96) were slightly higher than those of local meteoric water line of Yangtze River catchment (δD = 7.41 δ18O + 6.01). Most of the river isotopic values were located below the local meteoric water line, thereby implying that the Yangtze River water experienced a certain degree of evaporative enrichment on isotopic compositions of river water. The high fluctuations in the isotopic composition (e.g., deuterium excess [d‐excess]) in the middle to lower reaches during the initial stage of operation for the Three Gorges Dams (2003–2006) were due to heterogeneous isotopic signatures from the upstream water. In contrast to the normal stage (after 2010) characterized by the maximum water level and largest water storage, a relatively small variability in the deuterium excess was found along the middle to lower reaches because of the homogenization of reservoir water with a longer residence time and complete mixing. The effects of water from lakes and tributaries on the isotopic compositions in mainstream water were highlighted because of the high contributions of lakes water (e.g., Dongting Lake and Poyang Lake) efflux to the Yangtze River mainstream, which ranged from 21% to 85% during 2006 and 2013. These findings suggest that the retention and regulation of the Three Gorges Dams has greatly buffered the isotopic variability of the water cycle in the Yangtze catchment, thereby improving our understanding of the complex lake–river interactions along the middle to lower reaches in the future. 相似文献
14.
Some previous studies have shown that drying‐up of the lower Yellow River resulted from decreasing precipitation and excessive industrial and agricultural consumption of water from the middle and downstream regions of the Yellow River. On the basis of average air temperature, precipitation, and pan evaporation data from nearly 80 gauging stations in the Yellow River basin, the monotonic trends of major climate variables over the past several decades are analysed. The analysis was mainly made for 12 months and the annual means. The isograms for annual and typical months are given in the paper. The result shows that the average temperature in the study area exhibits an increasing trend, mainly because of the increase of temperature in December, January and February. The largest trend is shown in December and the smallest is in August. There are 65 of 77 stations exhibiting a downward trend for annual precipitation. In all seasons except summer, there is a similar trend in the upstream region of the Yellow River, south of latitude 35°N. It is interesting to note that the pan evaporation has decreased in most areas of the Yellow River basin during the past several decades. April and July showed the greatest magnitude of slope, and the area from Sanmenxia to Huayuankou as well as the Yiluo River basin exhibited the strongest declining trend. The conclusion is that the decreasing pan evaporation results from complex changes of air temperature, relative humidity, solar radiation, and wind speed, and both climate change and human activities have affected the flow regime of the Yellow River during the past several decades. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
15.
Moisture budget variations in the Yangtze River Basin, China, and possible associations with large-scale circulation 总被引：3，自引：2，他引：1
Zengxin Zhang Hui Tao Qiang Zhang Jinchi Zhang Nicola Forher Georg Hörmann 《Stochastic Environmental Research and Risk Assessment (SERRA)》2010,24(5):579-589
We analyzed seasonal and annual variations of the whole layer atmospheric moisture budget and precipitation during 1961–2005
and their associations with large-scale circulation in the Yangtze River basin, China. The results indicated increasing moisture
budget in summer and winter, but decreasing moisture budget in spring and autumn. Positive correlations between moisture budget
and precipitation illustrate tremendous impacts the moisture budget has on the precipitation changes across the Yangtze River
basin. In terms of seasonal variations, significant correlations were observed between precipitation and moisture budget in
spring and autumn in the upper Yangtze River basin. Besides, we also analyzed changes of geopotential height. The positive
trends of the geopotential height (850 hPa) were observed in the East Asia and the negative trends in the middle and west
Pacific Ocean, indicating increasing geopotential height from south to north in east Asia which largely limited the moisture
propagation to north China. While decreasing meridional geopotential height from west to east along the Yangtze River basin
caused more moisture propagation from the west to the east parts of the study region, which may benefit more precipitation
in the middle and lower Yangtze River basin. 相似文献
16.
Trend,periodicity and abrupt change in streamflow of the East River,the Pearl River basin 总被引：2，自引：0，他引：2 下载免费PDF全文
下载免费PDF全文 The East River in the Pearl River basin, China, plays a vital role in the water supply for mega‐cities within and in the vicinity of the Pearl River Delta. Knowledge of statistical variability of streamflow is therefore important for water resources management in the basin. This study analyzed streamflow from four hydrological stations on the East River for a period of 1951–2009, using ensemble empirical mode decomposition (EEMD), continuous wavelet transform (CWT) technique, scanning t and F tests. Results indicated increasing/decreasing streamflow in the East River basin before/after the 1980s. After the early 1970s, the high/low flow components were decreasing/increasing. CWT‐based analysis demonstrates a significant impact of water reservoirs on the periodicity of streamflow. Scanning t and F test indicates that significantly abrupt changes in streamflow are largely influenced by both water reservoirs construction and precipitation changes. Thus, changes of streamflow, which are reflected by variations of trend, periodicity and abrupt change, are due to both water reservoir construction and precipitation changes. Further, the changes of volume of streamflow in the East River are in good agreement with precipitation changes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
17.
AbstractCharacteristics of hydroclimatic change in the upper reaches of the Minjiang River are analysed using data collected over the past 50 years. The effect of autocorrelation of time series on trend analysis is removed by adopting a pre-whitening technique. Long-term hydrometeorological trend and abrupt changes are analysed by the Mann-Kendall test. The results were validated by the linear trend and Spearman methods. Correlations between runoff change with air temperature and with precipitation were studied with the Pearson method. The results clearly show that average air temperature in the upper reaches of the river is increasing, and precipitation decreasing, with differences in spatio-temporal distribution. Runoff change has a clear positive correlation with precipitation. Meteorological change, especially in precipitation, is the key governing influence of runoff volume. The annual runoff decrease, especially the decrease of inflow in spring and autumn and earlier appearance and longer duration of the low-flow season, will impact greatly on irrigation and municipal water supply. Therefore, relevant measures and further study are necessary. Editor Z.W. Kundzewicz; Associate editor Q. ZhangCitation Huang, X.R., Zhao, J.W., Li, W.H., and Jiang, H.X., 2013. Impact of climatic change on streamflow in the upper reaches of the Minjiang River, China. Hydrological Sciences Journal, 59 (1), 154–164. 相似文献
18.
Huai River Basin, as the sixth largest river basin in China, has a high‐regulated river system and has been facing severe water problems. In this article, the changing patterns of runoff and precipitation at 10 hydrological stations from 1956 to 2000 on the highly regulated river (Shaying River) and less‐regulated river (Huai River) in the basin are evaluated at the monthly, seasonal and annual scales using the Mann–Kendall test and simple linear regression model. The results showed that: (1) No statistically significant trends of precipitation in the upper and middle Huai River Basins were detected at the annual scale, but the trend of annual runoff at Baiguishan, Zhoukou and Fuyang stations in Shaying River decreased significantly, whereas the others were not. Moreover, the decreasing trends of runoff for most months were significant in Shaying River, although the trend of monthly precipitation decreased significantly only in April in the whole research area and the number of months in the dry season having significantly decreasing trends in runoff was more than that in the wet season. (2) The rainfall–runoff relationship was significant in both highly regulated river and less‐regulated river. In regulated river, the reservoirs have larger regulation capacity than the floodgates and thus have the smaller correlation coefficient and t‐value. In Huai River, the correlation coefficients decreased from upper stream to downstream. (3) The regulation of dams and floodgates for flood control and water supply was the principal reason for the decreasing runoff in Huai River Basin, although the decreasing precipitation in April in this basin was statistically significant. The findings are useful for recognizing hydrology variation and will provide scientific foundation to integrated water resources management in Huai River Basin. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
19.
Using annual precipitation and discharge data measured in the past five decades,this paper analyzed the regional differences over west China in terms of climate and discharge variations,and investigated the relationship between the regional characteristics and the activities of South and East Asian sum-mer monsoon. Results revealed that the precipitation and discharge in the upper reaches of the Yellow River (Central West China) have a negative correlation with those in Xinjiang (northwest China) and the Yarlung Zangbo River (the upper reaches of the Brahmaputra Rive,southwest China) regions. The geographical patterns of precipitation and discharge variations are different over west China,i.e. the regional climate displays the alteration of dry-wet-dry or wet-dry-wet from north to south in west China. The negative correlation of annual discharges between Xinjiang and the upper reaches of the Yellow River is found statistically significant in the decadal scale,and that between the Yarlung Zangbo River and the upper reaches of the Yellow River is found active in the interannual scale. The regional char-acteristics indicate that the discharge/precipitation variations in the upper reaches of the Yellow River are dominated by the East Asian summer monsoon while their variations in Xinjiang are affected by both the west wind and East Asian summer monsoon. 相似文献
20.
Abstract Supraglacial Imja Lake (lake level, 5010 m a.m.s.l.), Khumbu, Nepal Himalaya, has increased its size on the tongue of Imja Glacier since the 1950s. In order to clarify the mechanism of the lake expansion, the physical conditions, water budget and heat budget of the lake were examined by measuring water temperature, water turbidity, lake level, meteorology and water discharge. These measurements were carried out in the monsoon season of July 1997, when the glacier melt occurred in the ablation area with air temperature of more than 0°C. Density stratification in the lake is built up by an effect of water pressure on lake water, but, neglecting the effect, lake water density is defined by suspended sediment concentration rather than temperature. Glacier-melt water from the subaqueous part of the glacier terminus mixed with lake surface water of 4–8°C, and diffused the water of about 3°C into the deeper zone of the lake. This advective, thermal diffusion occurs by sediment-laden underflow and relatively clear density interflow. The sediment-laden underflow is induced by intermittent glacier-melt sediment discharge at the terminus, while the density interflow is probably produced by continuous glacier-melt water discharge. Calculation of water budget of the lake indicates that meltwater inflow at the glacier terminus and surface water outflow at the outlet determine the hydrological conditions of the lake. The net heat transfer by melting of the terminal ice and dead ice, connected to the lake expansion, was evaluated by calculating the heat budget of the lake. 相似文献