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1.
I.INTRODUCTIONThearidlandinNorthwestChina,richinlight,heat,landandmineralresources,isoneofthebiggestpotentialregionsforeconomicdevelopmentinthefuture.Itischaracterizedbydroughtclimate,scarceprecipitationandthereisnoagriculturewitholltirrigation(Liu,1980).Waterisnotonlythemostvaluablenaturalresources,butalsoveryimportantenvironmentalfactorinthisarea.Theoasesandwaterresourcesforhumansurvivalanddevelopmentaredistributedmainlyintheinlandriverbasins.Atpresentexploitationandutilizationofwater…  相似文献   

2.
Glacier area changes in the Qangtang Plateau are analyzed during 1970-2000 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid method.The results indicate that the melting of glaciers accelerated,only a few of glaciers in an advancing state during 1970-2000 in the whole Qangtang Plateau.However,the glaciers seemed still more stable in the study area than in most areas of western China.We estimate that glacier retreat was likely due to air temperature warming during 1970-2000 in the Qangtang Plateau.Furthermore,the functional model of glacier system is applied to study climate sensitivity of glacier area changes,which indicates that glacier lifespan mainly depends on the heating rate,secondly the precipitation,and precipitation increasing can slow down glacier retreat and make glacier lifespan prolonged.  相似文献   

3.
Impacts of Yulong Mountain Glacier on Tourism in Lijiang   总被引:3,自引:1,他引:2  
Introduction The mountain tourism has been repeatedly identified as potentially vulnerable to global climate change and has received greater research attention. Implications of climate change can be seen, for example, in less snow, receding glaciers, melt…  相似文献   

4.
The margin of the Greenland ice sheet has undergone rapid changes over the past decade as a result of the thinning, acceleration, and retreat of many fast-flowing tidewater outlet glaciers. Satellite observations show that three major tidewater outlet glaciers in Greenland retreated between 2000 and 2005, with synchronous increases in flow speed, causing a deficit in ice sheet mass budget and the potential for sea level rise. In this study, we investigated whether this acceleration was related to surface melt processes, and found that both flow speed and positive degree day (PDD) anomalies of the three glaciers varied together, indicating a causal relationship. Jakobshavn Isbræ had lower flow speeds before 2000, during which PDD anomalies were negative, except for modest warming in 1993 and 1995. From 1999–2000, during which it is thought a threshold was passed, the flow speed of the glacier started to increase. However, the two glaciers in east Greenland showed a delayed response. Abrupt warming occurred in the vicinity of the two glaciers around 2001, but flow speed did not increase until 2003 for the Helheim Glacier, and until 2004 for the Kangerdlugssuaq Glacier. Furthermore, the two eastern glaciers switched to a deceleration mode more quickly than Jakobshavn Isbræ. The observed differences in both acceleration and deceleration among the glaciers suggest that the relationship between surface melt and outlet glacier dynamics is not simple but complex.  相似文献   

5.
This paper presents a dynamic glacier model that simulates the processes in response of Glacier No. 1 in headwaters of the ürümqi River to various future climatic scenarios. The results indicate that the Glacier No. 1 will continue retreating if current climatic conditions prevail, until it reaches an equilibrium state of 1600 m in length after 700 to 800 years. If air temperature raise 1°C, the glacier would become a hanging glacier with a length of 300 m after 700 to 800 years. Due to its retreat, cooling function of the glacier would be weakened, resulting in the air temperature in glaciated area higher than that in ice-free areas. The results also indicate that the current glacier melt runoff is in higher value period in comparison with the runoff in the equilibrium state under the current climatic condition. If the air temperature continues increasing, however, the runoff would still increase to a new peak and then decrease rapidly. The project supported by the National Natural Science Foundation of China.  相似文献   

6.
PRESSURE OF WATER SHORTAGE ON AGRICULTURE IN ARID REGION OF CHINA   总被引:2,自引:0,他引:2  
1INTRODUCTIONWiththedevelopmentoftheworld,waterdemandisincreasing,especiallywiththegrowthofpopulationinthelast50years,waterdemandforirrigationhasgreatlyincreasedforfoodproduction.Inthearidandsemi-aridareas,watershortagebecomesaheavierproblemtorestrictfoodproduction,localeconomyandenvironmentalprotection.China,with22%ofthetotalpopulationintheworld,hasonly8%offreshwaterintheglobe;watershortagehasaffectedagricultureandresident'slifeinthenorthernChina.SomescientistsindicatedthatChina'swaters…  相似文献   

7.
青藏高原冰川变化遥感监测研究综述   总被引:1,自引:0,他引:1  
在全球变暖影响下,青藏高原冰川消融造成的冰川径流增大、冰湖溃决等问题威胁着山区及其周边居民的生命财产安全,对青藏高原冰川变化的研究日益紧迫。本文综述了国内外山地冰川变化遥感监测手段的发展、冰川面积及冰面高程变化的遥感监测研究现状、存在问题与发展趋势,并总结了中国青藏高原冰川变化遥感监测研究的主要成果。此外,本文基于2003-2009年ICESat/GLAS数据,计算了青藏高原各山区冰面高程变化及其冰川消融量。结果显示:青藏高原冰川面积持续减少,青藏高原冰面高程的平均变化为-0.24±0.03 m/a,冰川融水量为-14.86±11.88 km3/a,冰川变化呈现从青藏高原东、南外缘山区往内陆与西、北部山区减慢的时空特征。  相似文献   

8.
Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods flowed through Kusai and Hedin Noel Lakes into Yanhu Lake; since then, the four small endorheic catchments merged into one larger catchment. This hydrological process caused the rapid shrinkage of Zonag Lake and continuous expansion of Yanhu Lake. In this study,based on satellite images, meteorological data and field investigations, we examined the dynamic changes in the four lakes and analyzed the influencing factors. The results showed that before 2011, the trends in the four lake areas were similar and displayed several stages. The change in the area of Zonag Lake corresponded well to the change in annual precipitation(AP), but the magnitude of the change was less than that of a non-glacier-fed lake. Although increased precipitation was the dominant factor that caused Zonag Lake to expand, increased glacier melting and permafrost thawing due to climate warming also had significant effects. After the 2011 outburst of Zonag Lake, due to the increasing AP and accelerating glacier melting, the increases in water volume of the three lakes were absorbed by Yanhu Lake, and Yanhu Lake expanded considerably. According to the rapid growth rates in water level and lake area, Yanhu Lake is likely to burst in 1-2 years.  相似文献   

9.
The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the past 29 years from 1979 to 2007 were collected and analyzed using parametric and non-parametric methods, the connection between temperature and precipitation by the combination of grey correlation analysis method and the hypothesis testing for trend of climate change. The results show a high inc...  相似文献   

10.
Desertification has been notably expanding in China in the recent decade, especially in North China where dust/sand storm (DSS) frequently assaulted local communities. Analyses in marine ecology found that the earth ecosystem could be able to complement nutrient silicon for keeping sustain- able development of marine ecosystem, and decreasing CO2 concentration in the atmosphere; as a result, the area of desertification would be enlarged. Modern human being activities have resulted in constant changes in the amount of silicon transport from land into sea, leading to oversupply of nitrogen and phosphorus but silicon in seawater. The proportion of nitrogen, phosphorus and silicon was seriously im- balanced and the limitation of silicon for phytoplankton growth has become more serious. The silicon de- ficiency has damaged the marine ecosystem in coastal regions and slowed down the carbon sedimentation in the atmosphere of the world. The authors believe that the continual discharge of CO2 into the atmos- phere is the cause for the global warming including marine water temperature rise. Consequently, the earth ecosystem would have to trigger its complementary action to resume to the silicon balance by algae bloom in seawater for reducing air and water temperatures. In order to complement nutrient silicon into the sea, the ecosystem would transport silicon via the atmosphere; therefore, the desertification in the in- ner land is a natural reaction. As marine phytoplankton booming can reduce the CO2 concentration in the atmosphere and further ease the green-house effect, during this process, a large amount of silicon are de- manded by the ecosystem, which human being are unable to stop desertification from happening but slow down the progress and ease the risk. Therefore, as an important role in earth ecosystem, people should reduce the CO2 discharge into the atmosphere first; then, the normal function of river transporting silicon must be restored. In this way, the CO2 in the atmosphere can be kept in balance, the global warming slowed down, marine ecosystem development sustained, the drought in inner land eased, and the desert gradually under-controlled.  相似文献   

11.
西北地区水资源短缺,生态环境相当脆弱。随着西北地区大规模生态环境建设的实施,原来水资源的供需矛盾更为明显,处理好西北地区有限水资源中经济用水和生态用水的比例关系具有重要的意义。就西北地区的生态环境建设中水资源可持续开发和利用提出几点认识。  相似文献   

12.
Glaciers were solid reservoirs and important water resources in western China, but they were retreating significantly in context of global warming. Laohugou Glacier No. 12 was the largest valley glacier in Qilian Mountains. In this study, realtime kinematic (RTK) data, topographic map and WorldView-2 satellite imagery were used to measure changes in terminus, extent and volume of Laohugou Glacier No. 12. Results showed that Laohugou Glacier No. 12 was shrinking significantly since 1957. From 1960 to 2015, the terminus reduction of Laohugou Glacier No. 12 was 402.96 m (3.99%) in total, and glacier length decreased to 9.7 km from 10.1 km. Reduction of glacier area and volume were the most obvious. From 1957 to 2015, glacier area and volume decreased by 1.54 km2 (7.03%) and 0.1816 km3, respectively. Reduction trend of terminus and area was slowing in 1950 -1980s, even stable for a period in the mid-1980s, and then accelerated. Ice core analysis result and nearly meteorological station data shown an increasing trend of temperature in 1957 -2015, it was a main reason of continuous retreating of Laohugou Glacier No.12.  相似文献   

13.
STREAMFLOW CHARACTERISTICS OF THE EASTERN QINGHAI-XIZANG PLATEAU   总被引:1,自引:0,他引:1  
The eastern Qinghai-Xizang (Tibet) Plateau is the headwater area for many large Asian rivers. Permafrost occurs above 4,200 m a.s.l. and glaciers occupy the summits and high valleys of the east-west trending mountain chains. Annual runoff generally increases with precipitation which is augmented southward by the rise in topography. Rainfall, snow melt, glacier melt and groundwater are the primary sources of stream flow, and the presence of permafrost enhances the flashiness of runoff response to rainfall and snowmelt events. Peak flows are concentrated between June and September. And winter is low flow season. Three types of runoff patterns may be distinguished according to their primary sources of water supply: snowmelt and rainfall, glacier melt and snowmelt, and groundwater. Large rivers generally drain more than one environments and their runoff regime reflects an integration of the various flow patterns on the plateau.  相似文献   

14.
Climate change induces profound changes in mountain territories that affect the activities pursued there. Tourism is one activity that is strongly impacted by these changes. Most research on tourism in mountain regions has focused on winter sports tourism, but glacier tourism, a summer activity, is also severely affected by climate change-induced phenomena, including glacier retreat and other geomorphological processes. Given that Alpine glacier tourism has been pursued since the 18 th century and glaciers have been changing throughout this period, this article aims to examine the adaptations implemented by glacier tourism operators since the activity's beginnings. Through analysis of historical documents, glaciological surveys and semi-structured interviews, this paper reveals how tourism activities around the Mer de Glace(the largest French glacier) have been impacted by glacier fluctuations since the first visit to the area in 1741. The study reveals that these developments have mainly been driven by glacier retreat and associated paraglacial dynamics. More recently, the shortening of the period of snow cover on the glacier has also impacted tourism activities. Most of the adaptation strategies implemented by tourism operators during the period in question are found to be reactive, consisting in the installation of safety equipment, the renovation of access points or the building of new structures to allow tourist activities to continue despite the consequences of glacier retreat. Other strategies, such as the adoption of new activities by workers previously specialised in another, are identified that could be considered transformative strategies, although these were only adopted by workers when their activity was no longer feasible. The analysis of materials from 1741 to the present also reveals that the recent impacts of climate change on glacier tourism are much more significant and diverse than those produced by past fluctuations. Therefore, it is important that stakeholders take suitable measures to ensure the sustainable future of the Mer de Glace and other glacier tourism destinations.  相似文献   

15.
Glaciers in the Tomor region of Tianshan Mountains preserve vital water resources.However,these glaciers suffer from strong mass losses in the recent years because of global warming.From 2008 to 2009,a large-scale scientific expedition has been carried out in this region.As an individual reference glacier,the tongue area of Qingbingtan glacier No.72 was measured by the high precise Real Time Kinematic-Global Position System (RTK-GPS).In this paper,changes of the tongue area of Qingbingtan glacier No.72 has been studied based on topographic map,remote sensing image and the survey during 2008-2009 field campaign.Results indicated that the ice surface-elevation of the tongue area changed-0.22±0.14 m a-1 from 1964 to 2008.The estimated loss in ice volume was 0.014±0.009 km3,which represented a ~20 % decrease from the 1964 volume and was equivalent to average annual mass balance of-0.20±0.12 m water equivalent for the tongue area during 1964-2008.Terminus retreated by 1852 m,approximately 41 m a-1,with the area reduction of 1.533 km2 (0.034 km2 a-1) from 1964 to 2009.Furthermore,the annual velocity reached to ~70 m a-1.Comparing with the other monitored glaciers in the eastern Tianshan Mountains,Qingbingtan glacier No.72 experienced more intensive in shrinkage,which resulted from the combined effects of climate change and glacier dynamic,providing evidence of the response to climatic warming.  相似文献   

16.
The distribution of borehole temperature at four high-altitude alpine glaciers was investigated. The result shows that the temperature ranges from -13.4℃ to -1.84℃, indicating the glaciers are cold throughout the boreholes. The negative gradient (i.e., the temperature decreasing with the increasing of depth) due to the advection of ice and climate warming, and the negative gradient moving downwards relates to climate warming, are probably responsible for the observed minimum temperature moving to lower depth in boreholes of the Gyabrag glacier and Miaoergou glacier compared to the previously investigated continental ice core borehole temperature in West China. The borehole temperature at 10m depth ranges from -8.0℃ in the Gyabrag glacier in the central Himalayas to -12.9℃ in the Tsabagarav glacier in the Altai range. The borehole temperature at 10 m depth is 3-4 degrees higher than the calculated mean annual air temperature on the surface of the glaciers and the higher 10 m depth temperature is mainly caused by the production of latent heat due to melt-water percolation and refreezing. The basal temperature is far below the melting point, indicating that the glaciers are frozen to bedrock. The very low temperature gradients near the bedrock suggest that the influence of geothermal flux and ice flow on basal temperature is very weak. The low temperature and small velocity of ice flow of glaciers are beneficial for preservation of the chemical and isotopic information in ice cores.  相似文献   

17.
伴随全球气候变暖导致的海平面上升及沿海地区对地下水资源的超量开采,将会诱发海咸水入侵内陆地下水,导致海陆过渡带的迁移,影响区域社会经济及水资源安全。该文以山东半岛蓝色经济区为研究背景,选取区域内龙口、招远滨海区域作为研究区,首先对研究区内的地下水流场规律进行刻画,然后以模拟因子,对目前地下水超采情景下的海陆过渡带迁移规律进行量化分析研究,研究结果表明:龙口、招远滨海区域海陆过渡带的宽度约为1.5~4.5km,且内陆地下水位越高,海陆过渡带向内陆迁移的速度越慢、范围越小。该成果对研究山东半岛蓝色经济区海陆过渡带的迁移具有重要指导意义。  相似文献   

18.
Because of the large number and remoteness, satellite data, including microwave data and optical imagery, have commonly been used in alpine glaciers surveys. Using remote sensing and Geographical Information System (GIS) techniques, the paper presents the results of a multitemporal satellite glacier extent mapping and glacier changes by glacier sizes in the Mt. Qomolangma region at the northern slopes of the middle Himalayas over the Tibetan Plateau. Glaciers in this region have both retreated and advanced in the past 35 years, with retreat dominating. The glacier retreat area was 3.23 km2 (or o.75 km^2 yr^-1 during 1974 and 1976, 8.68 km^2 (or 0.36 km^2 yr^-1 during 1976 and 1992, 1.44 km^2 (or 0.12 km^2 yr^-1) during 1992-2ooo. 1.14 km^2 (or 0.22 km^2 yr^-1 during 2000-2003, and 0.52 km^2 (or 0.07 km^2 yr^-1 during 2003-2008, respectively. While supra-glacier lakes on the debris-terminus of the Rongbuk Glacier were enlarged dramatically at the same time, from 0.05 km^2 in 1974 increased to 0.71 km^2 in 2008, which was more than 13 times larger in the last 35 years. In addition, glacier changes also showed spatial differences, for example, glacier retreat rate was the fastest at glacier termini between 5400 and 5700 m a.s.l than at other elevations. The result also shows that glaciers in the middle Himalayas retreat almost at a same pace with those in the western Himalayas.  相似文献   

19.
以1972、1989、1996、2006、2017年5个不同时段的Landsat MSS/TM/ETM+/OLI遥感影像数据、数字高程模型(DEM)数据和气象数据为数据源,通过计算机自动提取与人工目视解译相结合的方法获取南阿尔泰山中部地区各时段的冰湖信息,利用GIS空间分析方法对该地区的冰湖面积进行统计,并分析研究区冰湖在不同规模、不同坡度、不同海拔状态下的时空变化特征。结果表明:①近45年来南阿尔泰山中部地区的冰湖面积呈"先减后增"趋势。1972-1996年研究区的冰湖面积从411.14 km2减少至400.83 km2,共减少了10.31 km2,减少速率为0.43 km2/a。从1996-2017年冰湖面积增加了15.42 km2;增长率为0.514 km2/a。②研究区冰湖分布主要集中在海拔低于2 200 m、坡度小于25°的区域,不同海拔区间和不同坡度区间的冰湖面积均呈"先减后增"趋势。③结合气温、降水、冰川面积以及冰储量变化数据分析发现,南阿尔泰山中部地区冰湖对气候变化具有明显的响应。温度、降水量及冰川融水是影响冰湖面积变化的主要因素;且这三者之间存在一种平衡关系,即温度升高冰川消融速度加快,从而对冰湖的收支平衡产生直接影响。当冰湖的补给量(即冰川融水和降水量之和)大于由温度升高引起的蒸发量时,冰湖面积会呈增长趋势;反之亦然。1970-1980年整个阿勒泰地区年代际降水量减少了19.28 mm,温度上升了0.25℃,因此1972-1989年研究区冰湖的蒸发水量大于补给水量,导致该时段冰湖面积呈退缩态势。1989-1996年该区降水量增加了19.67%,温度升高了0.62℃,但是增加的降水量却无法弥补由温度升高引起的冰湖蒸发量,因此1989-1996年研究区冰湖面积仍处于退缩状态。1996-2017年由于温度和降水量大幅增加导致冰湖面积呈不断增长趋势。   相似文献   

20.
豫西甘山第四纪冰斗系统的发现及其与MIS的耦合关系分析   总被引:1,自引:0,他引:1  
在调查东亚冷槽西壁冰川遗迹及其海拔梯度的过程中,发现了甘山冰斗系统与磨光面、擦痕、漂砾等冰川遗迹。进而对该冰斗系统进行成因分析的过程中,发现了冰斗系统的"冰斗环退"的形成方式。以此为基础,就甘山冰斗系统与MIS之间的耦合关系进行了对比分析。研究表明,甘山冰斗系统是以"冰斗环退"方式形成的,该冰斗环退系统完整展现了我国东部第四纪冰川作用的过程,对研究冰期的雪线高程、环境演化规律、冰川作用的进退等,都有着极其重要的意义。在"冰斗环退"的研究基础上,发现了对应的"冰斗环进"机制。冰斗环进代表了冰川作用由高向低推进过程,冰斗环退代表了冰川作用由低向高撤退过程。通过影像分析,初步将甘山冰斗系统划分四段,共解析出了50余套冰斗环,冰川作用的时代可追溯到2.56 Ma。根据冰斗的环进、环退特征,进而发现C28冰斗环所对应MIS56,也即1.60Ma,可能为我国第四纪冰川作用过程中的冰进向冰退演化的重要拐点。  相似文献   

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