西藏桑日县巴玉水电站上游石冰川分布特征     

许君利  刘时银  王建 《冰川冻土》2018,40(6):1207-1215

全球变暖背景下石冰川运动加快,石冰川舌部沉积物堆积增加,导致泥石流的风险增大,石冰川可能是冰冻圈地区未来重要的致灾因素之一。随着社会经济和技术水平不断提高,人类活动范围不断扩大,越来越多的工程建设向偏远的高海拔山区推进,不可避免地面临石冰川问题。拟建于雅鲁藏布江中游桑日-加查峡谷段的一级电站巴玉水电站上游是否存在不稳定的石冰川分布受到关注。鉴于此,利用0.5 m分辨率GEOeye-1遥感影像,通过石冰川特有的纹理特征,结合SRTM提取的坡度信息,通过人工解译识别出拟建巴玉水电站上游的石冰川分布信息。结果表明：（1）石冰川集中在雅鲁藏布江北侧上游,共有27条,覆盖总面积为12.2±0.9 km²,平均面积为0.5 km²,平均长度为1 456 m,平均宽度为280 m。（2）石冰川分布在海拔4 570~5 720 m之间,平均末端海拔为4 920 m,属于舌状石冰川群,近50%石冰川处于活跃期,其中5条发生了前缘垮塌现象,可能引起泥石流等大型灾害。  相似文献   

黄河源区阿尼玛卿山典型冰川表面高程近期变化   总被引：1，自引：0，他引：1  

蒋宗立  刘时银  郭万钦  李晶  龙四春  王欣  魏俊锋  张震  吴坤鹏 《冰川冻土》2018,40(2):231-237

阿尼玛卿山位于青藏高原的东缘,是黄河源区冰川分布比较集中的区域。该区域的冰川物质平衡变化研究对于冰川水资源评估及冰川对气候变化响应研究具有重要借鉴意义。通过TerraSAR-X/TanDEM-X数据的干涉测量方法获得阿尼玛卿山区冰川的高分辨、高精度的数字高程模型（DEM）,与SRTM DEM进行差分获得该区域冰川2000年至2013年间的表面高程变化。对比发现：近13 a来该区域典型大冰川表面高程整体均有所下降,唯格勒当雄冰川末端区域冰川表面高程平均下降（4.16±3.70）m,冰舌中部表面高程有所增加,冰川末端区域表碛覆盖范围有所增加;哈龙冰川表面高程从末端往上呈递减下降的趋势,平均下降（8.73±3.70）m;耶和龙冰川表面平均下降了（13.0±3.70）m,但从冰川末端往上1.6 km区段表面高程平均增加约25 m,冰舌中部表面高程下降明显,对比冰川编目数据、Landsat TM图像可知,该冰川在2000年至2009年间发生过跃动,冰川末端位置前进了约500 m。总体来说,即使存在个别冰川前进现象,该区域冰川在近13 a间仍处于退缩状态。  相似文献   

全球冰川面积现状及近期变化 ——基于2017年发布的第6版Randolph冰川编目   总被引：2，自引：2，他引：0  

牟建新  李忠勤  张慧  梁鹏斌 《冰川冻土》2018,40(2):238-248

基于2017年发布的第6版Randolph冰川编目资料,结合全球16个主要冰川区近期发表的冰川变化研究文献,系统分析了全球冰川面积现状及其近期变化。结果表明,全球（不包括南极与格陵兰冰盖）共发育山地冰川215 547条,总面积达705 739 km²,面积相对误差为4.2%。冰川数量以面积等级<1 km²的冰川（79.15%）为主,冰川面积以面积等级≥100 km²的冰川（54.9%）为主。分布在北极的冰川面积（45.5%）最多,分布在南极周边岛屿的冰川面积（18.8%）次之,分布在高亚洲（13.8%）和阿拉斯加（12.3%）的冰川面积再次之。近50年间全球冰川经历了强烈退缩,16个主要冰川区面积退缩率达11.3%,1960年以来的冰川面积年均退缩率为0.35%。由于目前尚缺乏多期冰川编目可供比较,全球范围内冰川变化的定量研究仍将是今后研究的重点。  相似文献   

极海洋型冰川是什么冰川——与景才瑞先生商榷   总被引：1，自引：0，他引：1  

李吉均  周尚哲 《冰川冻土》2018,40(1):1-6

施雅风和谢自楚曾将中国现代冰川分为极大陆型冰川、亚大陆型冰川和海洋型冰川。这个分类方案因符合中国现代冰川的基本特征而得到广泛承认与应用。近年,景才瑞提出“极海洋型冰川”的概念,示意第四纪冰期时中国东部中低山地既然不存在基本的冰川类型,则可能存在一种比海洋型冰川更加高温湿润的特殊冰川。本文认为,这样类型的冰川是不存在的。海洋型冰川已经涵盖了处于融点冰温的临界冰川,即使再多的降水,也不能在正温条件下演变成冰川。故“极海洋型冰川”的概念是不能成立的。第四纪环境研究表明,冰期时大陆架广泛出露,西伯利亚-蒙古高压强迫下的冬季风加强,中国东部气候是朝着更加干旱的方向变化的,其海洋型特征也要大大降低。  相似文献   

1984-2016年全球参照冰川物质平衡时空变化特征   总被引：4，自引：3，他引：1  

梁鹏斌  李忠勤  张慧  王飞腾  牟建新  何海迪 《冰川冻土》2018,40(3):415-425

基于世界冰川监测服务处（WGMS）发布的冰川物质平衡数据,对全球40条典型参照冰川物质平衡资料进行分析,结果表明：1984年以来,40条冰川中的36条在观测时段内处于物质平衡为负的状态,冰川普遍退缩,尤其在中纬度比较强烈;全球参照冰川物质平衡的多年平均值为-563 mm,累积物质平衡为-18 590 mm,且2000年之后出现了加速消融的变化趋势;全球参照冰川物质平衡的年代际平均值呈阶梯下降,每10年,物质平衡值下降200 mm左右;由于区域气候变化的差异性以及冰川对气候变化的响应程度不同,冰川物质平衡变化表现出显著的区域特征,物质平衡值由北到南出逐渐增大,空间上呈现出典型的纬度地带性和经度地带性特征;气温是控制冰川物质平衡变化的主要因子,物质平衡过程通常与各地区不同时间尺度的气候波动和变化显著相关。  相似文献   

音苏盖提冰川表面流速特征分析     

刘星月  蒋宗立  刘时银  张勇  龙四春  魏俊锋 《地球学报》2018,39(1):103-110

跃动冰川的监测相对比较困难。本文采用Sentinel-1所携带的C波段合成孔径雷达特征匹配方法(Feature-Tracking)获得了喀喇昆仑北坡克勒青河谷音苏盖提冰川物质平衡年内比较详细的冰川表面流速。分析发现:选取的音苏盖提三条分支冰川中,南斯嘎姆里冰川(Skamri Glacier)流速整体大于其余两条,三条分支均存在快速运动区,斯嘎姆里冰川和北分支积累区流速突增,可能存在雪崩现象;两条南分支冰川整体流速夏季大于其他季节,而北分支冬季流速大于其他季节。虽然三条分支均存在快速运动区域,但是即使是流速最快的南斯嘎姆里冰川在物质平衡年内的运动速度也只有119 m·a-1,说明该物质平衡年内音苏盖提冰川并不处于跃动期。  相似文献   

地基InSAR技术及其典型边坡监测应用   总被引：1，自引：1，他引：0       下载免费PDF全文

刘斌  葛大庆  李曼  张玲  王艳  郭小方  王毅 《中国地质调查》2018,5(1):73-81

为了开展边坡活动实时监测,研究以IBIS-L地基InSAR系统为代表的地基InSAR形变时序分析关键技术,进行针对不同变形特征的观测方案和数据处理方法的优化,并开展了奉节大树场镇灾后滑坡、神农架林区人工不稳定斜坡和备战铁矿露天采矿边坡等边坡活动的监测应用,以及备战铁矿隧道南口冰川运动的监测试验。4种类型边坡地基InSAR监测结果表明,在复杂工作情况下,地基InSAR设备具有较高的观测稳定性,在满足观测条件的情况下,地基InSAR测量精度能达到亚mm级,已成为监测边坡微小形变的重要技术手段。这扩展了形变监测模式从星载InSAR技术的“大尺度、宽覆盖”走向地基InSAR技术的“小尺度、局部精细测量”,进一步丰富了科研人员对边坡变形现象的动力学过程认识,为“星-地”联合InSAR技术监测地表形变过程奠定了技术基础。  相似文献   

Glacier area changes in the Nujiang-Salween River Basin over the past 45 years     

JI Xuan  CHEN Yunfang  JIANG Wei  LIU Chang  YANG Luyi 《地理学报(英文版)》2022,32(6):1177-1200

Automated image classification and visual interpretation of Landsat imagery were used to extract the glacier boundary in the Nujiang-Salween River Basin (NSRB) around the years 1975, 2000, and 2020. The spatiotemporal characteristics of glacier area changes in the NSRB were determined and the reasons for the spatial heterogeneity in glacier area changes were discussed, based on comparative analyses of temperature and precipitation data from meteorological stations around the NSRB. The results indicate that 1) the total glacier area in the NSRB decreased by 477.78 km² (28.17%) at a rate of -0.62%/a in 1975-2020. Most shrinkage occurred at low and mid altitudes, with the most severe occurring at 5290-5540 m, accounting for 40% of the total shrinkage. Considering other river basins in China, the relative glacier area change rate in the NSRB was similar to that for typical inland river basins in northwest China but lower than that for other transboundary river basins in the southeastern Tibetan Plateau. 2) These areal changes in the NSRB presented obvious regional differences. The glaciers in the Hengduan Mountains retreated significantly, followed by those in the Nyainqentanglha Mountains, with relatively low shrinkage observed in the Tanggula Mountains. The number of cold and hot spots indicating areal changes increased after 2000, along with their spatial heterogeneity. 3) The glacier shrinkage rate over different time intervals was positively correlated with temperature. Thus, spatial heterogeneity of climate change effects could elucidate differences in the glacier area change rate in different regions of the NSRB. The temperature rise was determined as the primary reason for the significant glacial retreat over the past 45 years. As the significant warming trend continues, the glacier area in the NSRB is likely to shrink further.  相似文献   

Reconsidering the Suitability Assessment Method for Glacier Tourism: A Case Study from Tibet,China     

YU Hu  XU Linlin  LIU Limin 《资源与生态学报(英文版)》2022,13(4):687-696

Glacier retreat is becoming more widespread and severe due to global warming, and improper exploitation of glacier resources by tourism activities accelerates the destruction of glacier landscapes. Therefore, establishing a set of quantitative assessment tools is critical for guiding the rational utilization of glacier tourism resources. This study selected regional tourism resources, the natural environment of glaciers, service support, and market demand factors to build a suitability assessment method for glacier tourism (SAMGT), and it used the Delphi and Analytic Hierarchy Process (AHP) to determine the index weights, and combined them with GIS analysis technology. The Tibet autonomous region was proposed in this study as a case to build the SAMGT and provide scientific support for the rational development, scientific management, and sustainable development of glacier tourism resources. With regard to influencing the suitability of glacier tourism resource development, the results indicate that the weights of glacier resource endowment, ecological vulnerability, and tourism resource combination were high whereas that of market demand-related factors was low. The glacier tourism resource development area in Tibet can be divided into suitable, relatively suitable, barely suitable, and unsuitable exploitation zones, accounting for 5.39%, 9.76%, 15.28%, and 69.57% of the total area, respectively. Five representative glaciers were selected to verify the validity or test the rationality of SAMGT and prove that the model is reasonable, innovative, and effective from the perspectives of multiple dimensions and the comprehensiveness of the selected indicators.  相似文献   

Recent patterned grounds development on a glacier surface (Dovrefjell,central Norway): an ephemeral periglacial activity in a paraglacial context     

Riwan Kerguillec 《Geografiska Annaler: Series A, Physical Geography》2014,96(1):1-7

Researches carried out on the main glacier of the Dovrefjell massif, Scandes Mountains, Norway (62° N; 9° E) point to recent periglacial features which are presently directly developed on the ice. This original location raises the problem of their morphodynamic significance and a hypothesis of ephemeral periglacial activity in a paraglacial context is proposed here.  相似文献