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1.
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
2.
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
3.
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
4.
近50 年气候变化背景下中国冰川面积状况分析 总被引：10，自引：0，他引：10
根据近年来中国典型区域冰川面积变化遥感监测数据,结合139 个地面站的气温、降水量与28 个探空站的0 ℃层高度气象资料,分析了近50 年气候变化背景下中国冰川面积状况。结果表明,研究区冰川面积从20 世纪60-70 年代的23982 km2减小到21 世纪初的21893 km2,根据冰川分布进行加权计算后冰川面积退缩了10.1%,对时间插补后得到1960 年以来的冰川面积年均变化率为0.3 % a-1。就冰川面积变化的空间分布特征而言,天山的伊犁河流域、准噶尔内流水系、阿尔泰山的鄂毕河流域、祁连山的河西内流水系等都是冰川退缩程度较高的区域。近50 年中国冰川区夏季地面气温与大气0 ℃层高度均呈上升趋势,而降水量的增幅却相对轻微,增长的降水量不足以抵消升温对冰川的影响,气候变暖是影响冰川面积变化的主要因素。 相似文献
5.
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
6.
1900-2007年横断山区部分海洋型冰川变化 总被引：12，自引：4，他引：8
横断山区7条海洋型冰川近百年进退速度变化呈现出以退缩为总趋势的阶段性变化,具体表现为20世纪初至1930s的冰川稳定,1930s-1960s的冰川后退,1970s-1980s的冰川稳定或减速后退,20世纪80年代中期以来的冰川后退,这与我国、北半球及横断山区同期的气候变化呈明显对应,展现出冷干阶段冰川稳定或前进、暖湿阶段后退的态势,但各冰川的变化幅度因纬度位置、坡向、冰川规模、局地环境等而存在明显差异.1982/83年大、小贡巴冰川、海螺沟冰川冰舌段的消融水当量分别为2710mm、3139 mm和5281 mm,1990/91-97/98期间海螺沟冰川冰舌段的年均消融水当量为6157 mm,比1982/83年增加了876 mm.2002年夏季白水1号冰川的积雪消融量由于表碛覆盖较少表现出明显的随海拔升高而降低的特征,平均消融水当量为1086.25 mm,2008.9-19.10.13期间白水1号冰川物质平衡花竿的观测表明,花竿布设区域10月6号左右转入物质积累期.期间日均积累深为1cm,折合水当量5mm. 相似文献
7.
细胞周期检测点激酶2（checkpoint kinase 2,CHEK2）是由CHEK2基因编码的DNA双链断裂损伤的重要信号转导蛋白,参与G1期、S期和G2/M期的阻滞。CHEK2基因突变和乳腺癌病理特征与预后相关,是乳腺癌重要的易感基因。CHEK2有1100delC、Y390C以及I157T等多种突变形式,通过多条不同通路,如SDF-1和IL-6、BRCA1/2等影响细胞周期监测点的功能。在化疗方面,寻找CHEK2抑制剂以增强化疗或放疗对肿瘤细胞的杀伤效果也是当前的研究热点之一。本文针对乳腺癌中CHEK2突变的形式、机制以及可能的治疗靶点做一综述。 相似文献
8.
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
9.
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
10.
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
11.
Wilfred H. Theakstone & Frank M. Jacobsen 《Geografiska Annaler: Series A, Physical Geography》1997,79(4):201-214
Twentieth-century changes in Norwegian glaciers have been pronounced, but the different geometries and dynamics of the glaciers have caused different responses to similar climatic changes. Close to the Arctic Circle, all the glaciers of Svartisen, the largest ice-covered area of northern Scandinavia, have retreated since the beginning of the century. However, several of the smaller glaciers which end at relatively high altitude have experienced both periods of advance and periods of retreat since the mid-1960s. The mass balance of Engabreen, the largest of the West Svartisen glaciers, was positive in 21 of the 27 years to 1995–96. The sizes of most of the glaciers of the Okstindan area, 60 km south-east of Svartisen, have also decreased throughout the twentieth century, but Corneliussens Bre, a small glacier at the eastern side of the massif, has been advancing since 1970. The areas supplying some of the southern glaciers of Okstindan have been reduced as a result of changes in ice thickness at high altitude. Studies of glacier change are aided by the use of digital terrain models (DTMs). Triangular irregular network DTMs of the surface and bed topography of the largest of the Okstindan glaciers, Austre Okstindbreen, have been used in studies of mass-balance variations and changing surface flow patterns between 1976 and 1995. 相似文献
12.
PuYu Wang ZhongQin Li ChunHai Xu Ping Zhou WenBin Wang Shuang Jin HongLiang Li 《寒旱区科学》2019,11(1):41-49
This study makes an attempt to investigate through statistical analysis the correlation between changes in ice volume and area of glaciers. Using data from nine sample glaciers in the Tian Shan, the results show that a linear relation exists between changes in ice volume and area, with a correlation coefficient of 0.700. However, the accuracy estimation is difficult due to the limited number of samples. The correlation was not improved after adding eleven glacier samples in other mountains. Two reference glaciers are then analyzed in more detail. The linear correlation coefficient is higher than 0.800 when using the observed changes in ice volume and area during different periods on Urumqi Glacier No. 1, which suggests that the linear relation is valid for one glacier for different periods if its shape does not change noticeably and also for other glaciers of the same shape during the same period. The relation between changes in ice volume and area of Qingbingtan Glacier No. 72 is different during different periods due to change in the shape of the glacier tongue and the influence of the debris cover. Moreover, errors in glacier-change monitoring and-volume estimation have an important influence on the correlation results. Therefore, further study needs to focus not only on the distinction between glacier types and between different periods but also on the accuracy of volume estimation. 相似文献
13.
1973-2010年阿尔金山冰川变化 总被引：3，自引：0，他引：3
利用1973 年MSS、1999 年ETM+和2010 年TM遥感影像资料,通过遥感图像处理和GIS技术,提取了阿尔金山地区三个时期的冰川信息,同时结合周边气象资料进行分析。结果表明:① 1973-2010 年,研究区冰川面积从347.99 km2 减少到293.77 km2,退缩了54.22km2,占1973 年冰川总面积的15.58%,年均退缩速率为0.42%·a-1。近10 年来冰川退缩尤为剧烈,年均退缩速率达到0.58%·a-1;② 研究区东段冰川退缩速率快于中段和西段;③ 冰川规模越小,退缩越明显;④ 研究区东坡冰川的面积退缩率最大,北坡次之,东南坡最小;⑤ 气温升高和降水在波动中变化不大是造成研究区冰川退缩的主要原因;⑥ 通过分形理论对研究区冰川空间结构特征进行分析,预计研究区冰川今后的消融速率仍将处于较高状态。 相似文献
14.
Torkild Bakken Jon Anders Kongsrud Eivind Oug Sabine K.J. Cochrane Toril Loennechen Moen & Beata E.B. Solbakken 《Polar research》2010,29(1):1-21
A thorough literature review has been undertaken to establish the first complete account of polychaetes recorded from the area around the volcanic island of Jan Mayen. The annotated checklist lists 121 species-level taxa, representing an increase from the 75 species previously recorded. The checklist is based on existing records, supplemented with material sampled in 1999, from which 42 species new to the area were reported. Some previously reported species from the area have been excluded because of inadequate documentation. The polychaete fauna of Jan Mayen is comparable with that of the mainland Norwegian coast and the Svalbard area. No taxa unique to the island were found. However, knowledge of the marine invertebrate fauna in general at Jan Mayen is sparse because few surveys have been undertaken there. It is expected that future expeditions will reveal further new taxon records for the area. 相似文献
15.
西藏玛旁雍错流域冰川与湖泊变化及其对气候变化的响应 总被引：12，自引：2，他引：10
利用遥感和地理信息系统技术,基于1974,1990,1999和2003年4个不同时期的遥感影像,包括Landsat系列影像,ASTER影像和地形图,研究了玛旁雍错流域(面积7786 km2)内冰川与湖泊的变化及其对气候变化的响应。研究结果表明,由于气候变暖,在过去30年里该流域冰川和湖泊都以退为主,有进有退。自1974年到2003年,冰川面积从107.92 km2减少到100.39 km2,冰川退缩明显加速。由于年降水量减少、蒸发量增大,30年中湖泊总面积从782.24 km2减少到748.08 km2。湖面的缩小与扩涨都在加速,尤其是小湖泊变化更明显,湖泊的加速变化可能是青藏高原高海拔内陆流域水循环过程加速的表征之一。 相似文献
16.
利用1959年地形图、2008年ASTER数字遥感影像及数字高程模型,在地理信息系统技术支持下分析了新疆阿尔泰山友谊峰地区冰川的变化特征。研究表明：1959-2008年该区冰川整体呈萎缩趋势,且变化幅度相对较大。相对于1959年,2008年冰川面积和数量分别变化-32.5%和-27.9%。其中,小于1 km2的冰川面积平均变化率为-66.7%,面积小于0.5 km2的冰川面积变化率大于-70%,面积大于1 km2以上的冰川面积变化率为-35.0%,1~5 km2的冰川面积变化率为-27.9%。冰川末端平均后退253 m,末端退缩比例为-18.3%,且南坡冰川末端变化率大于北坡。分析发现,研究区冰川面积亏损较大主要缘于该区小冰川分布数量较多（面积小于1 km2的冰川数量达75%),对气候变化的响应较为敏感。 相似文献
17.
采用1:5万地形图、Landsat MSS/TM/ETM+/OLI遥感影像及数字高程模型数据,利用遥感和地理信息系统技术,并结合狮泉河、和田和于田3个气象站点1968-2013年的气温、降水量数据对松木希错流域的冰川、湖泊面积变化及其原因进行分析。结果表明：① 1968-2013年流域冰川面积不断退缩,由139.25 km2减少至137.27±0.02 km2,共减少1.98±0.02 km2,减少百分比为1.42%,2001年以后冰川退缩速度加快;② 1968-2013年松木希错面积不断扩张,由25.05 km2增加至32.62±0.02 km2,共扩张7.57±0.02 km2,扩张百分比为30.22%,且2001年之后扩张速率加快,在年代际上与冰川的退缩具有较好的耦合性;③ 1968-2013年湖面潜在蒸散量减少和降水增加分别是导致湖泊扩张的第一和第二影响因素,而升温引起的冰川、冻土融水增加有一定贡献,但影响较小且在年际尺度上不显著。 相似文献
18.
Modelling Changes in Glacier Mass Balance that may Occur as a Result of Climate Changes 总被引：2，自引：0，他引：2
Roger J. Braithwaite & Yu Zhang 《Geografiska Annaler: Series A, Physical Geography》1999,81(4):489-496
Projections of changes in glacier mass balance caused by climate changes involve modelling present mass balance in terms of climate and then perturbing the climate variables to calculate future mass balance. The simplest model involves linear regression of mass balance time series on temperature and precipitation data at stations close to the glacier but we prefer the degree-day model. This model uses temperature and precipitation to calculate snow accumulation, snow and ice melting, and possible refreezing of meltwater at regular altitude intervals on a glacier. Model parameters are still somewhat uncertain and are established for individual glaciers by tuning the model mass balance as a function of altitude to fit observed data. The model has been applied to 37 glaciers in different parts of the world so far and some details are given for Storglaciären to illustrate the approach. The sensitivity of modelled mass balance to a +1°C temperature increase shows a wide range for the 37 glaciers from about 0.1 to 1.3 m water a−1 . Sub-polar glaciers have lower temperature sensitivities, and maritime and tropical glaciers have higher sensitivities. 相似文献
19.
1959年来中国天山冰川资源时空变化 总被引：1，自引：0，他引：1
基于两期冰川编目数据与气象数据,对天山1959年来冰川资源的时空变化特征进行研究。研究发现：① 天山地区现有冰川7934条,面积7179.77 km2,冰储量756.48 km3。冰川数量以面积< 1 km2的冰川居多,面积以1~10 km2和≥ 20 km2的冰川为主,冰川集中分布在海拔3800~4800 m之间。② 在四级流域中,阿克苏河流域冰川面积最大为1721.75 km2,面积最小的是伊吾河流域,为56.03 km2。在各市（州）中,阿克苏地区冰川资源量最多,其面积和储量分别占天山总量的43.28%和68.85%;冰川资源量最少的市（州）是吐鲁番地区,面积和储量仅占天山总量的0.23%和0.07%。③ 1959年来,天山地区冰川面积减少了1619.82 km2（-18.41%）,储量亏损了104.78 km3（-12.16%）,其中数量以< 1 km2的冰川减少最多,面积减少以< 5 km2的冰川最为严重。④ 冰川变化呈现明显的区域差异,变化速度最快的是天山东段博格达北坡流域,变化最慢的是中部的渭干河流域。初步分析认为夏季气温显著上升带来的消融大于年内降水带来的积累是天山冰川退缩的主要原因。 相似文献
20.
1960年以来中国天山冰川面积及气候变化 总被引：11，自引：3，他引：8
Based on the statistics of glacier area variation measured in the Chinese Tianshan Mountains since 1960,the response of glacier area variation to climate change is discussed systematically.As a result,the total area of the glaciers has been reduced by 11.5% in the past 50 years,which is a weighted percentage according to the glacier area variations of 10 drainage basins separated by the Glacier Inventory of China (GIC).The annual percentage of area changes (APAC) of glaciers in the Chinese Tianshan Mountains is 0.31% after the standardization of the study period.The APAC varies widely for different drainage basins,but the glaciers are in a state of rapid retreat,generally.According to the 14 meteorological sta-tions in the Chinese Tianshan Mountains,both the temperature and precipitation display a marked increasing tendency from 1960 to 2009 at a rate of 0.34℃·(10a)-1 and 11 mm·(10a) -1,respectively.The temperature in the dry seasons (from November to March) increases rapidly at a rate of 0.46℃·(10a)-1,but the precipitation grows slowly at 2.3 mm·(10a)-1.While the temperature in the wet seasons (from April to October) grows at a rate of 0.25℃·(10a)-1,but the precipitation increases at 8.7 mm·(10a)-1.The annual and seasonal climatic trends ac-celerate the retreat of glaciers. 相似文献