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1.
1990-2011年西昆仑峰区冰川变化的遥感监测 总被引：2，自引：0，他引：2
本文应用Landsat 5、7 TM、ETM+影像分析1990-2011年昆仑山西段昆仑峰区冰川变化特征,结果表明:1990-2011年冰川面积减少16.83 km2,退缩率仅为0.65%,冰川退缩趋势不明显。单条冰川变化有进有退,中峰冰川末端在2002-2004年以661 m/a的速率前进,初步判定为跃动冰川。1991-1998年,崇测冰川面积增加9.47 km2,冰川末端以200 m/a的速率前进,不排除有跃动冰川的可能性。尽管近年来全球气温普遍上升,大量冰川处于退缩状态,但统计已有研究结果发现近50年来青藏高原存在冰川长度、面积增加,冰川物质平衡为正的现象,表现出冰川对气候变化复杂的反馈机制。通过分析气象站点和冰芯资料,研究区周边地区气温上升、降水量缓慢增加可能是冰川微弱退缩的原因之一;增强的西风环流带来更多的降水、研究区以极大陆型大规模冰川为主,也可能是冰川退缩幅度较小的原因。 相似文献
2.
RS analysis of glaciers change in the Heihe River Basin,Northwest China,during the recent decades 总被引：2，自引：1，他引：1
Baojuan Huai Zhongqin Li Shengjie Wang Meiping Sun Ping Zhou Yan Xiao 《地理学报(英文版)》2014,24(6):993-1008
The Heihe River Basin is the second largest inland river basin in Northwest China and it is also a hotspot in arid hydrology, water resources and other aspects of researches in cold regions. In addition, the Heihe River Basin has complete landscape, moderate watershed size, and typical social ecological environmental problems. So far, there has been no detailed assessment of glaciers change information of the whole river basin. 1：50,000 topographic map data, Landsat TM/ETM＋ remote sensing images and digital elevation model data were used in this research. Through integrated computer automatic interpretation and visual interpretation methods, the object-oriented image feature extraction method was applied to extract glacier outline information. Glaciers change data were derived from analysis, and the glacier variation and its response to climate change in the period 1956/1963–2007/ 2011 were also analyzed. The results show that：（1） In the period 1956/1963–2007/2011, the Heihe River Basin＇s glaciers had an evident retreat trend, the total area of glaciers decreased from 361.69 km2 to 231.17 km~2; shrinking at a rate of 36.08%, with average single glacier area decrease 0.14 km~2; the total number of the glaciers decreased from 967 to 800.（2） Glaciers in this basin are mainly distributed at elevations of 4300–4400 m, 4400–4500 m and 4500–4600 m; and there are significant regional differences in glaciers distribution and glaciers change.（3） Compared with other western mountain glaciers, glaciers retreat in the Heihe River Basin has a higher rate.（4） Analysis of the six meteorological stations＇ annual average temperature and precipitation data from 1960 to 2010 suggests that the mean annual temperature increased significantly and the annual precipitation also showed an increasing trend. It is concluded that glacier shrinkage is closely related with temperature rising, besides, glacier melting caused by rising temperatures greater than glacier mass supply by increased precipitation to 相似文献
3.
近50年黑河流域的冰川变化遥感分析 总被引：2，自引：0，他引：2
黑河流域作为中国西北地区第二大内陆流域,其景观类型完整、流域规模适中、社会生态环境问题典型,已成为寒区、旱区水文与水资源研究的热点地区。本研究结合1：5 万地形图、Landsat TM/ETM+遥感影像及数字高程模型数据,运用面向对象的图像信息自动提取方法,建立冰川信息提取知识规则,对近50 年黑河流域的冰川变化进行遥感分析。结果表明：（1）20 世纪60 年代黑河流域内的967 条冰川到2010 年左右,减少为800 条冰川,减少数量明显;冰川面积由361.69 km2退缩为231.17 km2,共减少130.51 km2,退缩率为36.08%,平均每条冰川面积退缩0.14 km2。（2）黑河流域冰川分布及变化存在显著的区域差异性,黑河冰川退缩率比北大河大16%左右;冰川末端主要分布在4300~4400 m、4400~4500 m和4500~4600 m海拔区间内。（3）与西部其他山地冰川相比,黑河流域冰川退缩率较高。（4）根据流域内6 个气象站资料分析表明,降水增加对冰川的补给无法弥补气温上升导致的冰川消融所带来的物质损失,是黑河流域冰川普遍萎缩的关键因素。 相似文献
4.
玉龙喀什河源区32年来冰川变化遥感监测 总被引：36，自引：4，他引：32
根据航空相片、地形图、遥感影像数据分析了玉龙喀什河源区的冰川变化,结果表明,1970~2001年本区冰川总体上以稳定冰川的数量占多数,但由于部分冰川的退缩使得整个研究区的冰川表现为萎缩的趋势。1970~1989年冰川规模有扩大的趋势,冰川面积、储量分别增加了1.4 km2、0.4781 km3,约占1970年研究区相应总量的0.12%、0.19%;而1989~2001年的冰川面积、储量分别比1970年减少了0.5%、0.4%,是西北干旱区冰川面积变化幅度最小的区域。分析认为该区域1970~1989年冰川扩大可能与该地区的冰川对20世纪60年代末温度降低、降水量增加有10~20年滞后响应有关;1989~2001年冰川退缩,主要受温度快速上升影响,而丰富的降水对冰川退缩起到缓冲的作用。 相似文献
5.
1978-2015年喀喇昆仑山克勒青河流域冰川变化的遥感监测 总被引：1，自引：1，他引：0
本文采用1978、1991、2001和2015年的Landsat MSS、TM、ETM+和OLI遥感影像,通过遥感图像计算机辅助分类和目视解译等方法提取冰川边界,分析喀喇昆仑山克勒青河流域冰川在1978-2015年间的进退变化。结果表明：1978-2015年间研究区冰川面积由1821.70 km2减少至1675.92 km2,减少145.78 km2,占1978年冰川总面积的8.00%;冰川消融率较低,在气候变暖的背景下反而呈现出退缩速率由快变慢的趋势。研究区东南向冰川退缩率明显高于西北向,冰川退缩率随冰川规模的增大而减小。研究区内有27处冰川在1978-2015年间发生过特殊的前进现象,面积与长度显著增加。其中,木斯塔冰川西侧冰川末端在1996-1998年间前进速度为904 m/a,乔戈里冰川东侧冰川末端在2007-2009年间前进速度为446 m/a,5Y654D0097冰川末端在1978-1990年间前进速度为238 m/a,初步判定这三条冰川为跃动冰川。以10 a为滞后期分析研究区周边气象站点资料发现：研究区气温持续升高,降水量以1981年为分界点呈现“先减后增”趋势是冰川退缩速率减慢的原因之一;此外,亚大陆型冰川性质、巨大山势条件和高山冷储作用,也可能是冰川退缩幅度较小的原因。 相似文献
6.
哈尔里克山脉冰川的快速退缩已经影响到吐鲁番坎儿井的水量,先前关于该区冰川研究不够细致,且最新资料报道较为短缺。以哈尔里克山脉冰川为研究对象,基于Landsat TM/ETM+和OLI影像（1992、2002、2010、2016年）,通过比值阈值法、目视解译结合GIS技术,提取了该地区四期冰川边界,同时对研究区周边气温、降水以及日照时数进行线性趋势分析,研究其与冰川的响应关系。结果表明：（1）1992-2016年,哈尔里克山脉冰川总体呈现出持续退缩趋势,面积退缩了13.18%,年均退缩率为0.56%,近年来退缩速率有所减缓。（2）近似估算的冰储量在过去25 a间减少了18.33%,冰川物质亏损将对该区短缺的水资源提供了危险的信号。（3）冰川退缩率与冰川规模呈指数函数变化趋势;低海拔区冰川存在明显的末端升高趋势;N和NW向的冰川占明显优势,但N向退缩率最慢。（4）分形理论分析表明该地区冰川未来退缩将趋于一种稳定状态。该区气温和日照时数的显著上升导致其冰川退缩,同时冰川规模、海拔和坡向分布也是冰川变化的重要因素;对比发现该区冰川退缩速率较天山其他区域慢。 相似文献
7.
近30年珠穆朗玛峰国家自然保护区冰川变化的遥感监测 总被引：18，自引：2，他引：16
利用1976、1988和2006年的3期陆地卫星遥感数据,采用面向对象的解译方法并结合专家知识分类规则自动提取珠穆朗玛峰国家自然保护区(以下简称珠峰保护区)3个时期的冰川信息,并利用遥感、地理信息系统和图谱的方法对冰川时空分布特征和变化及其原因与不确定性进行了分析。结果如下:(1)2006年珠峰保护区内冰川面积为2710.17±0.011km2,为研究区总面积的7.41%,主要分布在研究区南部海拔4700～6800m的高山区;(2)1976-2006年,珠峰保护区冰川持续退缩明显,总面积减少501.91±0.035km2,冰湖扩张迅速(净增加36.88±0.035km2);研究区南坡子流域冰川退缩率(16.79%)高于北坡子流域(14.40%);珠峰保护区冰川以退缩为主,退缩冰川主要分布于海拔4700～6400m,退缩区上限海拔为6600～6700m;(3)1976年以来,气温显著上升和降水减少是冰川退缩的关键因素。 相似文献
8.
中国西部冰川度日因子的空间变化特征 总被引：16，自引：2，他引：14
在冰川与积雪消融研究中,度日模型应用较为广泛,该模型是基于冰雪消融与气温,尤其是正积温之间的线性关系建立的。度日因子是该模型的重要参数,反映了单位正积温产生的冰雪消融量,其空间变化特征对于不同模型模拟冰雪消融过程的精度有较大影响。 本文根据中国西部不同地区数十条冰川的短期考察和观测资料,分析了西部冰川度日因子的空间变化特征,结果表明：由于青藏高原及其周围地区独特的气候和热量条件,西部冰川度日因子具有明显的区域特征。在同一冰川上,度日因子的空间变化较为明显。从冰川类型来看,与极大陆型及亚大陆型冰川相比,海洋型冰川的度日因子较大。总体看来,西部冰川的度日因子由西北向东南逐渐增大,这与中国西部冰川的气候环境变化趋势是一致的,即在干冷的气候条件下,度日因子较小;而在暖湿的气候条件下度日因子较大。 相似文献
9.
纳木错流域近30年来湖泊-冰川变化对气候的响应 总被引：20，自引：1，他引：19
Based upon the 1970 aero-photo topographic map, and TM/ETM satellite images taken in 1991 and 2000, the authors artificially interpreted boundaries of lake and glaciers in Nam Co Catchment, and quantified lake-glacier area variations in different stages by "inte-grated method" with the support of GIS. Results show that from 1970 to 2000, lake area in-creased from 1942.34 km2 to 1979.79 km2 at a rate of 1.27 km2/a, while glacier area de-creased from 167.62 km2 to 141.88 km2 at a rate of 0.86 km2/a. The increasing rate of lake in 1991-2000 was 1.76 km2/a that was faster than 1.03 km2/a in 1970-1991, while in the same period of time, the shrinking rates of glaciers were 0.97 km2/a and 0.80 km2/a respectively.Important factors, relevant to lake and glacier response to the climate, such as air tempera-ture, precipitation, potential evapotranspiration and their values in warm and cold seasons,were discussed. The result suggests that temperature increasing is the main reason for the accelerated melting of glaciers. Lake expansion is mainly induced by the increase of the gla-cier melting water, increase of precipitation and obvious decrease of potential evapotranspi-ration. Precipitation, evaporation and their linkages with lake enlargement on regional scale need to be thoroughly studied under the background of global warming and glacier retreating. 相似文献
10.
The response of lake-glacier variations to climate change in Nam Co Catchment,central Tibetan Plateau,during 1970–2000 总被引：1，自引：0，他引：1
Based upon the 1970 aero-photo topographic map, and TM/ETM satellite images taken in 1991 and 2000, the authors artificially interpreted boundaries of lake and glaciers in Nam Co Catchment, and quantified lake-glacier area variations in different stages by ＂integrated method＂ with the support of GIS. Results show that from 1970 to 2000, lake area increased from 1942.34 km^2 to 1979.79 km^2 at a rate of 1.27 km^2/a, while glacier area decreased from 167.62 km^2 to 141.88 km^2 at a rate of 0.86 km^2/a. The increasing rate of lake in 1991-2000 was 1.76 km^2/a that was faster than 1.03 km^2/a in 1970-1991, while in the same period of time, the shrinking rates of glaciers were 0.97 km^2/a and 0.80 km^2/a respectively. Important factors, relevant to lake and glacier response to the climate, such as air temperature, precipitation, potential evapotranspiration and their values in warm and cold seasons, were discussed. The result suggests that temperature increasing is the main reason for the accelerated melting of glaciers. Lake expansion is mainly induced by the increase of the glacier melting water, increase of precipitation and obvious decrease of potential evapotranspiration. Precipitation, evaporation and their linkages with lake enlargement on regional scale need to be thoroughly studied under the background of global warming and glacier retreating. 相似文献
11.
纳木错流域近30 年来湖泊 - 冰川变化对气候的响应 总被引：13，自引：0，他引：13
利用1970 航测地形图和1991、2000 年两期卫星影像数据, 人工建立数字高程模型 (DEM), 解译不同时期的湖泊、冰川边界, 在GIS 技术支持下采用图谱的方法, 定量分析了 湖泊、冰川的面积变化情况。结果表明, 自1970~2000 年期间, 纳木错湖面面积从1941.64 km2 增加到1979.79 km2, 增加的速率为1.27 km2/a; 流域内冰川的面积从167.62 km2 减少到141.88 km2, 退缩速率为0.86 km2/a。其中, 湖面面积在1991~2000 年的增加速率为1.76 km2/a, 明显大于其在1970~1991 年的1.03 km2/a; 而冰川面积在1991~2000 年的退缩速率为 0.97 km2/a, 明显大于其在1970~1991 年的0.80 km2/a。对比该流域前后两个时期的气温、降水和蒸发变化, 发现升温幅度的增加是冰川加速退缩的根本原因, 而湖面的加速扩张主要受冰川的加剧退缩及其引起的融水增加影响, 但与区域降水量略微增加和蒸发量显著减少也具有密切联系。区域降水增加和蒸发减少及其与湖面扩张之间的内在联系仍是一个需要深入探讨的问题。 相似文献
12.
Mountain glaciers are sensitive to environment. It is important to acquire ice flow velocities over time for glacier research and hazard forecast. For this paper, cross-correlating of optical images is used to monitor ice flow velocities, and an improvement, which is called ＂moving grid,＂ is made to this method. For this research, two remote-sensing images in a certain glacier area, dur-ing different times are selected. The first image is divided into grids, and we calculated the correlation coefficient of each window in the grid with the window on the second image. The window with the highest correlation coefficient is considered the counter-part one on the first image. The displacement of the two corresponding windows is the movement of the glacier, and it is used to calculate glacier surface velocity. Compared to the traditional way of dividing an image with ascertain grid, this method uses small steps to move the grid from one location to another adjacent location until the whole glacier area is covered in the image, thus in-creasing corresponding point density. We selected a glacier in the Tianshan Mountains for this experiment and used two re-mote-sensing images with a 10-year interval to determine this method. 相似文献
13.
以Landsat MSS/TM/ETM+/OLI 遥感影像和数字高程模型为数据源,在遥感和地理信息技术支持下,分析了阿尔金山地区1973、1999、2010、2015 四期冰川变化特征。研究表明：（1）1973-2015 年,冰川总面积共退缩了58.78 km2,年均退缩率为0.40%·a-1,东段退缩速率最快,其次是西段,中段最慢,且冰川退缩速率呈现出先变快后变慢的变化趋势。（2）各个坡向都出现不同程度的退缩,偏南坡比偏北坡冰川退缩严重。（3）冰川面积退缩速率与规模等级呈现反相关关系,小规模冰川退缩速率快。（4）冰川分布随海拔变化呈正态分布,海拔越低退缩速率越快。统计分析气象数据表明,气候变暖是冰川退缩的主要原因,同时地形与冰川规模也影响冰川变化。 相似文献
14.
A geochronological approach to understanding the role of solar activity on Holocene glacier length variability in the Swiss Alps 总被引：3，自引：0，他引：3
Anne Hormes Jürg Beer Christian Schlüchter 《Geografiska Annaler: Series A, Physical Geography》2006,88(4):281-294
We present a radiocarbon data set of 71 samples of wood and peat material that melted out or sheared out from underneath eight presentday mid‐latitude glaciers in the Central Swiss Alps. Results indicated that in the past several glaciers have been repeatedly less extensive than they were in the 1990s. The periods when glaciers had a smaller volume and shorter length persisted between 320 and 2500 years. This data set provides greater insight into glacier variability than previously possible, especially for the early and middle Holocene. The radiocarbon‐dated periods defined with less extensive glaciers coincide with periods of reduced radio‐production, pointing to a connection between solar activity and glacier melting processes. Measured long‐term series of glacier length variations show significant correlation with the total solar irradiance. Incoming solar irradiance and changing albedo can account for a direct forcing of the glacier mass balances. Long‐term investigations of atmospheric processes that are in interaction with changing solar activity are needed in order to understand the feedback mechanisms with glacier mass balances. 相似文献
15.
本文选取南极Ｎｅｌｓｏｎ站、横断山的海螺沟冰川、喜马拉雅山的达索普冰川、西昆仑的古里雅冰川和天山的托木峰冰川为研究对象,以化学成分作为指标,作了模糊聚类分析。结果表明,在不同水平下分类,冰川之间关系程度不同,反应的气候环境也不同。南极与青藏高原冰川中离子浓度存在差异,尤其是Ｎａ＋和Ｃａ２＋的含量差异显著。Ｎｅｌｓｏｎ站的Ｃａ２＋／Ｎａ＋之值比青藏高原各冰芯低许多,其与海水中Ｃａ２＋／Ｎａ＋之值相当。Ｃａ２＋／Ｎａ＋之值体现了冰川离海洋的距离,Ｃａ２＋／Ｎａ＋之值越小,则冰川离海洋越近,反之则越大。 相似文献
16.
念青唐古拉山脉西段雪线高度变化遥感观测 总被引：3，自引：0，他引：3
利用Landsat TM/ETM+/8 OLI和HJ1A遥感影像资料作为数据源,通过目视解译方法,提取念青唐古拉山脉西段雪线高度变化值,同时对研究区周边气温与降水变化趋势进行分析,研究其与冰川变化的关系。结果表明：2004~2013年北坡13条冰川和南坡15条冰川的雪线高度都呈升高的趋势;从整体上来考察,北坡雪线高度升高值为14 m/a,南坡升高值为4.9 m/a,北坡升高速度比南坡快;自1964年以来,研究区气温升高趋势显著,降水增加不明显,气候变暖是冰川退缩的主要原因;北坡冰川比南坡冰川经历更大的物质负平衡,主要是由于气温的升高率北坡比南坡快所致。 相似文献
17.
Glaciers are one of the most important land covers in alpine regions and especially sensitive to global climate change. Remote sensing has proved to be the best method of investigating the extent of glacial variations in remote mountainous areas. Using Landsat thematic mapping (TM) and multi-spectral-scanner (MSS) images from Mt. Qomolangma (Everest) National Nature Preserve (QNNP), central high Himalayas for 1976, 1988 and 2006, we derived glacial extent for these three periods. A combination of object-oriented image interpretation methods, expert knowledge rules and field surveys were employed. Results showed that (1) the glacial area in 2006 was 2710.17 ± 0.011 km2 (about 7.41% of the whole study area), and located mainly to the south and between 4700 m to 6800 m above sea level; (2) from 1976 to 2006, glaciers reduced by 501.91 ± 0.035 km2 and glacial lakes expanded by 36.88 ± 0.035 km2; the rate of glacier retreat was higher in sub-basins on the southern slopes (16.79%) of the Himalayas than on the northern slopes (14.40%); most glaciers retreated, and mainly occurred at an elevation of 4700–6400 m, and the estimated upper limit of the retreat zone is between 6600 m and 6700 m; (3) increase in temperature and decrease in precipitation over the study period are the key factors driving retreat. 相似文献
18.
采用Landsat TM/ETM+/OLI影像数据,结合比值阈值法与目视解译提取冰川边界,分析了喜马拉雅山冰川在1990-2015年的进退变化。结果表明：近25 a来喜马拉雅山冰川整体呈退缩趋势,冰川面积由23 229.27 km2减少至20 676.17 km2,共减少2 553.10 km2,退缩率为10.99%,研究时段喜马拉雅山冰川加速退缩,尤其是近5 a来,加速退缩的趋势尤为显著。研究区冰川主要分布在海拔4 800~6 200 m范围内,且随着海拔升高冰川分布面积呈先增加后减小趋势,综合分析喜马拉雅山山体海拔特征可知,5 200~5 600 m很可能是研究区的“第二大降水带”。依据山岳冰川分布特征,我们将研究区冰川分为山谷冰川、冰斗冰川、冰斗-山谷冰川、悬冰川和平顶冰川,其中悬冰川的数量最多,山谷冰川的分布面积和平均规模最大。结合研究区周边气象格点数据,同时以12a为滞后期发现,近25a来喜马拉雅山冰川持续退缩很可能是气温升高和降水减少共同作用的结果,且未来十几年内冰川仍可能处于持续退缩的状态。 相似文献
19.
Based upon the 1970 aero-photo topographic map, and TM/ETM satellite images taken in 1991 and 2000, the authors artificially interpreted boundaries of lake and glaciers in Nam Co Catchment, and quantified lake-glacier area variations in different stages by “inte-grated method” with the support of GIS. Results show that from 1970 to 2000, lake area in-creased from 1942.34 km2 to 1979.79 km2 at a rate of 1.27 km2/a, while glacier area de-creased from 167.62 km2 to 141.88 km2 at a rate of 0.86 km2/a. The increasing rate of lake in 1991–2000 was 1.76 km2/a that was faster than 1.03 km2/a in 1970–1991, while in the same period of time, the shrinking rates of glaciers were 0.97 km2/a and 0.80 km2/a respectively. Important factors, relevant to lake and glacier response to the climate, such as air tempera-ture, precipitation, potential evapotranspiration and their values in warm and cold seasons, were discussed. The result suggests that temperature increasing is the main reason for the accelerated melting of glaciers. Lake expansion is mainly induced by the increase of the gla-cier melting water, increase of precipitation and obvious decrease of potential evapotranspi-ration. Precipitation, evaporation and their linkages with lake enlargement on regional scale need to be thoroughly studied under the background of global warming and glacier retreating. 相似文献
20.
表碛覆盖型冰川是中国西部较为常见的冰川类型。表碛层存在于大气—冰川冰界面,强烈影响大气圈与冰冻圈之间的热交换。表碛厚度的空间异质性可极大地改变冰川的消融率和物质平衡过程,进而影响冰川径流过程和下游水资源。基于Landsat TM/TIRS数据,运用能量平衡方程反演了贡嘎山地区冰川表碛厚度,研究了贡嘎山地区冰川在1990—2019年间表碛覆盖范围及厚度变化情况,同时对比了东西坡差异。结果表明：① 贡嘎山地区冰川表碛扩张总面积达43.824 km2。其中,海螺沟冰川扩张2.606 km2、磨子沟冰川1.959 km2、燕子沟冰川1.243 km2、大贡巴冰川0.896 km2、小贡巴冰川0.509 km2、南门关沟冰川2.264 km2,年均扩张率分别为3.2%、11.1%、1.5%、0.9%、1.0%和6.5%;② 海螺沟冰川、磨子沟冰川、燕子沟冰川、大贡巴冰川、小贡巴冰川、南门关沟冰川表碛平均增厚分别为5.2 cm、3.1 cm、3.7 cm、6.8 cm、7.3 cm和13.1 cm;③ 西坡冰川表碛覆盖度高,表碛覆盖年均扩张率低,冰川末端退缩量小;东坡冰川表碛覆盖年均扩张率高,但表碛覆盖度总体低于西坡,冰川末端退缩量大。 相似文献