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1.
Glacier variations and climate warming and drying in the central Himalayas   总被引:24,自引:4,他引:20  
Repeat measurements of glacier terminus positions show that glaciers in the central Himalayas have been in a continuous retreat situation in the past decades. The average retreat rate is 5.5-8.7 m/a in Mt. Qomolangma(Everest) since the 1960s and 6.4 m/a in Mt. Xixiabangma since the 1980s. In recent years, the retreat rate is increasing.Ice core studies revealed that the accumulation rate of glaciers has a fluctuating decrease trend in the last century with a rapid decrease in the 1960s and a relatively steady low value afterwards. Meteorological station record indicates that the annual mean temperature has a slow increase trend but summer temperature had a larger increase in the past 30 a. All these suggest that the glacier retreat results from precipitation decrease in combination with temperature increase,and hence glacier shrinkage in this region will speed up if the climatic warming and drying continues.  相似文献   

2.
An ice core record at Mt. Qomolangma (Everest) since 1954 reveals a sharp decline in net-accumulation in the 1960s, and the annual net-accumulation during the 1970s to the beginning of the 1990s is only half of that at the end of the 1950s. The decreased net-accumulation is coincident with glacier retreat, which is associated with recent temperature increase in the region that intensified the ablation. Under the background of global warming, such glacier variation trends will aggravate.  相似文献   

3.
Ma  LingLong  Tian  LiD  Pu  JianChen  Wang  PengLing 《科学通报(英文版)》2010,55(20):2088-2096
This paper calculated and evaluated the area and ice volume changes of Kangwure Glacier in Mt. Xixiabangma, middle of Himalayas in the past 3 decades, based on the field survey of glacier boundary position by differential GPS and glacier depth by Ground Penetrating Radar (GPR), together with the topographic map and remote sense data. The studied data showed that the Kangwure Glacier has experienced significant mass deficit since the 1970s, with 34.2% of area loss, 48.2% of ice volume loss and 7.5 m of average thickness decrease. This result revealed that the ice volume loss of Himalayan glaciers was more serious than expected. Analysis of meteorological data from two weather stations in the region of Mt. Xixiabangma, shows that the air temperature of this region has risen from the middle of the 20th century to the beginning of the 21st century. Significant retreat of Himalayas glacier driven by climatic warming will have a remarkable impact on hydrology and ecosystem.  相似文献   

4.
High mountains may serve as a condenser for persistent organic pollutants. In the present study, soil and grass samples from Mt. Qomolangma region, China were collected from 4600 to 5620 m a.s.I and were analyzed for polycyclic aromatic hydrocarbons (PAHs) to determine if they are concentrated at colder, more elevated sites and to evaluate their possible resources and fractionation. The total PAHs concentration in soil samples was 〈 600 ng g^-1, the critical value to differentiate PAHs levels in remote and urban regions. This implied the PAHs levels at Mt. Qomolangma are relatively low and what one might expect in such a remote region of the world. These low values may represent a soil background for mid-latitude Northern Hemisphere soils away from the direct influence of an anthropogenic source. As for the distribution pattern, the low molecular weight PAHs were prone to accumulate at higher altitude, while the high molecular weight PAHs inversely related or unrelated with elevation. Based on high concentration of phenanthrene at elevated sample site and the ratios of individual PAHs, we deduced that home-heating combustion and vehicle emission may result in the constitution trait of PAHs in this mountain region. Monsoon traveling over India, Pakistan and other countries with dense population may carry contaminant to Mt. Qomolangma region.  相似文献   

5.
A total of 14 surface snow (0-10 cm) samples were collected along the climbing route (6500-8844 m a.s.h) on the northern slope of Mt. Qomolangma in May, 2005. Analysis of elemental concentrations in these samples showed that there are no clear trends for element variations with elevation due to redistribution of surface snow by strong winds during spring. In addition, local crustal aerosol inputs also have an influence on elemental composition of surface snow. Comparison between elemental concentration datasets of 2005 and 1997 indicated that data from 2005 were of higher quality. Elemental concentrations (especially for heavy metals) at Mt. Qomolangma are comparable with polar sites, and far lower than large cities. This indicates that anthropogenic activities and heavy metal pollution have little effect on the Mt. Qomolangma atmospheric environment, which can be representative of the background atmospheric environment.  相似文献   

6.
Li  ShengHai  Yao  TanDong  Tian  LiDe  Wang  PengLing 《科学通报(英文版)》2011,56(18):1912-1920
To better understand ultra-high-altitude climate characteristics and their changes, an automatic weather station was installed on August 4, 2005 on the Mt. Xixiabangma Dasuopu glacier (28°23.04′N, 85°43.72′E, 6900 m a.s.l.) in the middle of the Himalayas. Mountain weather conditions were observed continuously and automatically. This paper is the first to publish meteorological data for a whole year for a high-elevation region, and analyze wind direction, wind speed, air temperature, air pressure and humidity. Analysis of the observation data reveals that this region was strongly influenced by the westerly jet from October 10, 2005 to April 21, 2006 and by the Indian monsoon from May to September. The seasonal transitions of the westerly jet were characterized by changes in meteorological elements. In winter, influenced by the westerly jet, the wind speed in the study region was very high and fluctuated violently, gale days were frequent, temperature and air pressure fluctuated dramatically, the diurnal range of temperature decreased and the diurnal range of air pressure increased, relative humidity and specific humidity declined sharply, and air was dry. In summer, influenced by the Indian monsoon, the relative humidity and specific humidity were high. In addition, we analyzed reanalysis data for the location of the automatic weather station. The results confirmed that this region was strongly affected by the westerly jet from October 10, 2005 to April 21, 2006 and the observations that the seasonal transitions of the westerly jet were characterized by changes in meteorological elements.  相似文献   

7.
慕士塔格峰冰川变化遥感研究   总被引:7,自引:0,他引:7  
以位于新疆维吾尔族自治区西南部的慕士塔格峰冰川为例,利用研究区1965年经航片校对的地形图和2001年5月的ASTER遥感影像为信息源,通过遥感图像处理技术和专家指导下的人工解译得到1965,2001年两期冰川边界图,用GIS统计该地区冰川面积,并分析冰川变化总趋势.结果表明,近36年来,慕士塔格峰冰川整体呈现退缩趋势,冰川面积减少了1.11%,而山峰西侧和南侧的部分冰川有前进的现象.  相似文献   

8.
本着重分析了新疆天山麓城镇体系结构特征及存在的问题,并对该区域城镇开发模式以及城镇今后发展布局提供了设想。  相似文献   

9.
Yang  Wei  Yao  TanDong  Xu  BaiQing  Ma  LingLong  Wang  ZhiHui  Wan  Ming 《科学通报(英文版)》2010,55(20):2097-2102
Little is known about recent variation of temperate glaciers on the Tibetan Plateau, although they are of particular theoretical and practical interests in terms of climate change and water supply. The study of glacier mass balance and terminus variation for six temperate glaciers in the Parlung Zangbo River basin, southeast Tibetan Plateau, shows the facts of the overall negative mass balance and the continued terminus retreat from 2005/2006 to 2007/2008. The mass balances of smaller glaciers were more negative compared to larger glaciers. Referring the trend of glacier mass balance in the Hengduan Mountains, the Himalayas and glacier shrinkage in southeast Tibetan Plateau, the mass loss and recession of temperate glacier in this region are expected if the current climate condition continues.  相似文献   

10.
Hou  Shugui  Qin  Dahe  Yao  Tandong  Zhang  Dongqi  Chen  Tuo 《科学通报(英文版)》2002,47(20):1746-1749
Three ice cores recovered from the Himalayas (i.e. the East Rongbuk Glacier and the Far East Rongbuk Glacier at Mt. Qomolangma (Everest), and the Dasuopu Glacier at Xixiabangma) show a sharp decline in the accumulation rates since the 1950s, which is consistent with the precipitation fluctuation over India and the low northern latitude zone (5°-35°N). Correspondingly, an increasing trend is observed for the ice core accumulations from the central and northern Qingh ai-Tibetan Plateau (i.e. the Xiao Dongkemadi Glacier in the central Tanggula Mountains, the Guliya Ice Cap in the western Kunlun Mountains, and the Dunde Ice Cap in the Qilian Mountains) since the 1950s, which is consistent with the precipi tation fluctuation over the middle-high northern latitude zone (35°-70°N). However, the variation magnitude of the high-elevation ice core accumulations is more significant than that of precipitation at the low-eleva- tion places, suggesti ng its extra sensitivity of high-elevation areas to climatic change. The inter-d ecadal abrupt change of the African-Asian summer monsoon in the1960s may attribute to the recent ice core accumulation change during the recent decades.  相似文献   

11.
The maritime glaciers are sensitive to climate change because of high annual precipitation and high air temperature in the region. A combined comprehensive study was carried out based on glacier mass balance observation, GPS-based glacier terminus position survey, glacier Ground Penetrating Radar, topography maps and RS satellite images in the Kangri Karpo Mountains, Southeast Tibet. The study revealed a strong ice mass loss and quick glacier retreat since the 1970s. Ata Glacier, one glacier from the south slope of the Kangri Karpo Mountains, has formed a 6-km-long terminal moraine zone at the end of the glacier since the 1970s, and the accelerating retreat is largely due to the strong glacier surface melting. Mass balance study on the other four glaciers on the northern side of the Kangri Karpo Mountains shows that they are in large negative mass balance and the glaciers had retreated 15--19 m from May 2006 to May 2007. The in-situ glacier observation also shows that the glacier retreat is more obvious in small glaciers. The enhanced ice mass deficit caused by climate warming and the ongoing extinction of many small glaciers in this region could seriously affect the water resources, environ- ments, local climate and regional sustainable development in the near future.  相似文献   

12.
武陵山地区种子植物区系特征及植物地理学意义   总被引:19,自引:0,他引:19  
武陵山地区地处湘鄂川黔交界,面积约10万km2,从科,属,种水平对区种子植物区系特征进行研究,结果表明,(1)该区产种子植物201,1005属,4119种,地理成分以亚热带(至温带)分布为主(占总属数的56.8%和总种数的90.49%),中国特有属64属,中国特有种达2682种(其中武陵山地区特有126种,武际人山区以外的华中区特有675种)。(2)该区保存有长苞铁极,水杉,粗榧,厚朴,鹅掌楸,水青属,八角莲属,马蹄芹属等起源或重要化化地;(3)该区与邻近区系具有广泛交流和渗透,经初步确定分别有109种,96种,67种和109种以武 陵山地区为分布区东界,西界,南界和北界,另外所含东亚成分由西向东方向分布式样的359种中,有303种正处于该方向迁移和扩散的重要通道(武陵山走廊)上,因此,武陵山地区在中国植物区系甚至个东亚植物区系中具有十分重要的意义。  相似文献   

13.
帕隆藏布流域位于中国海洋性冰川最为发育的藏东南地区,近年来随着全球温室效应加剧,帕隆藏布流域冰川变化极为显著。采用多期遥感影像,对1994~2015年间帕隆藏布流域波密至然乌段的冰川变化趋势、原因及其影响进行研究。结果表明:(1)20余年间冰川总面积减少了451. 72 km2,各冰川每年大约退缩2. 48%~2. 95%,气温升高以及降雨量减少是导致冰川面积持续退缩的主要原因。(2)由于帕隆藏布江南岸山坡所接收的太阳辐射热量更少,但降水却更加充沛,使得帕隆藏布江南岸冰川分布面积及覆盖率远大于北岸,而冰川退缩速率远小于北岸。(3)冰川的不断退缩使得沟道上游大量冻融松散物源在冰雪融水的外动力条件下,进入沟道形成松散堆积物源,导致流域内大规模发育冰川泥石流。由于帕隆藏布江南岸冰川规模更大,导致帕隆藏布江南岸冰川泥石流更为发育。(4)冰川变化动态监测对冰川泥石流机理分析以及预警研究工作有着重要的参考指导价值。  相似文献   

14.
Continuous Bi profile of the East Rongbuk (ER) ice core near Mt. Qomolangma reveals nine major volcanic events since AD 1800. Compared with Volcanic Explosivity Index (VEI), it shows that the concentrations of Bi in the ER ice core can reflect the major volcanic events within the key areas. This provides a good horizon layer for ice core dating, as well as a basis for reconstructing a long sequence of volcanic records from the Qinghai-Xizang (Tibet) Plateau ice cores. Supported jointly by National Basic Research Program of China (Grant No. 2007CB411501), National Natural Science Foundation of China (Grant No. 90411003), Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KZCX3-SW-344) and Hundred Talents Project of the Chinese Academy of Sciences  相似文献   

15.
Bacterial abundance in surface snow between 6600 and 8000 m a.s.l. on the northern slope of Mt. Ev- erest was investigated by flow cytometry. Bacterial diversity in serac ice at 6000 m a.s.l., glacier melt- water at 6350 m, and surface snow at 6600 m a.s.l. was examined by constructing a 16S rRNA gene clone library. Bacterial abundance in snow was higher than that in the Antarctic but similar to other mountain regions in the world. Bacterial abundance in surface snow increased with altitude but showed no correlation with chemical parameters. Bacteria in the cryosphere on Mt. Everest were closely related to those isolated from soil, aquatic environments, plants, animals, humans and other frozen environ- ments. Bacterial community structures in major habitats above 6000 m were variable. The Cyto- phaga-Flavobacterium-Bacteroides (CFB) group absolutely dominated in glacial meltwater, while β-Proteobacteria and the CFB group dominated in serac ice, and β-Proteobacteria and Actinobacteria dominated in surface snow. The remarkable differences among the habitats were most likely due to the bacterial post-deposition changes during acclimation processes.  相似文献   

16.
Mt. Everest, the zenith of the world, plays an impor- tant role in the global climate change. During the lastdecade, some studies on glacier and snow have been undertaken in this region. The climate and environment changes in the past hundred years have b…  相似文献   

17.
基于Landsat遥感影像,采用目视解译的方法提取了青藏高原内部那曲地区冰湖和冰川1990、2000、2010及2020年4期边界数据,并分析近30年来该地区冰湖变化的特征与原因.结果表明:那曲地区现有冰湖255个,总面积(27.829±4.62) km2,冰湖主要集中在东南部,其次是西南部;1990—2020年,研究区新增冰湖72个,面积增长6.14 km2;冰湖扩张趋势明显,具体表现为低海拔地区(≤4 700 m)原有冰湖快速扩张,较高海拔地区(>5 100~5 700 m)新增冰湖集中出现;气温与降水是冰湖变化的关键因素,由于降水与气温分布及变化存在时空差异,冰湖变化呈现“南快北慢,逐期加快”的特征;冰湖与冰川的位置关系也会影响冰湖变化,离冰川位置越近,对冰湖发育越有利,同时与冰湖接触的冰川退缩速率相较于其余冰川有更大的退缩速率,但冰川与冰湖面积变化速率并无明显相关性.   相似文献   

18.
Beryllium-7 (^7Be) and lead-210 (^210Pb) radioactivity in aerosols collected, from October 2002 to January 2004 at Mt. Waliguan, by the Global Atmospheric Watch (GAW) Station, Qinghai Province is presented. The data were analyzed together with simultaneously measured surface ozone concentrations. We found that short time variations of ^7Be and ^210Pb were linked to alternations of synoptic weather around the Mt. Waliguan region. ^210Pb showed the lowest concentration in summer while ^7Be showed no obvious seasonal changes. Relatively high ^7Be and ^210Pb radioactivity was observed at Mt. Waliguan when compared with the observations at other mountain sites in other parts of the world. Surface ozone and ^7Be showed a consistent seasonal variation. Surface ozone correlated fairly well with ^7Be/^210Pb ratio. This suggested that vertical transport from higher altitudes of the atmosphere has predominant effects on the budget of surface ozone at Mt. Waliguan.  相似文献   

19.
近代以来,众多日本人士奔赴泰山,访古览胜,对泰山展开了一系列的深入记录和研究,其中日本记者、随笔家涩川玄耳于大正年间多次登泰山,并作多篇见闻录、诗歌集及对泰山研究的论著,以独特的文化视角,审视泰山人文和历史.以涩川玄耳的泰山研究为中心,可探讨近代日本人笔下的泰山面貌和心中的泰山感悟.  相似文献   

20.
The Eastern Kunlun Mt. had been subjected to uplift together with the Qinghai-Xizang (Tibet) Plateau before the Early Pleistocene, and yet the Mt, did not protrude out of the Plateau surface. During that period lakes spread all over the studied region, with the drainage systems being all short rivers flowing into the lakes. At the end of the Early Pleistocene, intensive tectonic uplift led to the rising of the Eastern Kunlun Mt. and made the Mt. protrude onto the Plateau surface. As a result, a fault depression valley formed extending nearly from west to east along the fault belt of the Southern Kunlun Mt. Lakes in this region died out, surface runoffs joined into the valley of the Southern Kunlun Mt. resulting in a large river streaming nearly from west to east. Around 150 kaBP, because of the strong differential movement, rivers, such as the Jialu River and the Golmud River, retrogressively eroded seriously, cutting through the Burhan Budai Mt. Then they pirated the large river and divided it into four portions. Owing to the uplift of the Eastern Kunlun Mt., strongly retrogressive erosion of the upper reaches of the Jialu River has made the watershed of the Buqingshan Mt. migrate 6–10 km southward since Holocene. At present, it remains a stronger trend of retrogressive erosion developing upward to the basin of the Yellow River Source and it seems that the Jialu River is scrambling for the streamhead of the Yellow River.  相似文献   

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