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Characteristics of recent temperate glacier fluctuations in the Parlung Zangbo River basin, southeast Tibetan Plateau
Wei Yang,TanDong Yao,BaiQing Xu,LingLong Ma,ZhiHui Wang,Ming Wan
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-010-3214-4
Abstract: 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.
Glacier changes from 1966–2009 in the Gongga Mountains, on the south-eastern margin of the Qinghai-Tibetan Plateau and their climatic forcing  [PDF]
B. T. Pan,G. L. Zhang,J. Wang,B. Cao
The Cryosphere , 2012, DOI: 10.5194/tc-6-1087-2012
Abstract: In order to monitor the changes of the glaciers in the Gongga Mountain region on the south-eastern margin of the Qinghai-Tibetan Plateau, 74 monsoonal temperate glaciers were investigated by comparing the Chinese Glacier Inventory (CGI), recorded in the 1960s, with Landsat MSS in 1974, Landsat TM in 1989, 1994, 2005, and ASTER data in 2009. The remote sensing data have been applied to map the glacier outline by threshold ratio images (TM4/TM5). Moreover, the glacier outlines were verified by GPS survey on four large glaciers (Hailuogou (HLG), Mozigou (MZG), Yanzigou (YZG), and Dagongba (DGB)) in 2009. The results show that the area dominated by the 74 glaciers has shrunk by 11.3% (29.2 km2) from 1966 to 2009. Glacier area on the eastern and western slopes of the Gongga Mountains decreased by 9.8% and 14.6% since 1966, respectively. The loss in glacier area and length is, respectively, 0.8 km2 and 1146.4 m for the HLG Glacier, 2.1 km2 and 501.8 m for the MZG Glacier, 0.8 km2 and 724.8 m for the YZG Glacier, and 2.4 km2 and 1002.3 m for the DGB Glacier. Decades of climate records obtained from three meteorological stations in the Gongga Mountains were analyzed to evaluate the impact of the temperature and precipitation on glacier retreat. The mean annual temperatures over the eastern and western slopes of the Gongga Mountains have been increasing by 0.34 K decade 1 and 0.24 K decade 1 (1988–2009), respectively. Moreover, mean annual precipitation has only increased by 1% in the past 50 yr. The increasing amount of precipitation could not compensate for the glacier mass loss due to the temperature increase in the Gongga Mountains. This suggests that the warming of the climate is probably also responsible for the glacier retreat in the study region. At the region scale, glacier changes were also controlled by local topographical factors.
Glacier changes from 1966–2009 in the Gongga Mountains, on the south-eastern margin of the Qinghai-Tibetan Plateau and their climatic forcing  [PDF]
B. Pan,G. Zhang,J. Wang,B. Cao
The Cryosphere Discussions , 2011, DOI: 10.5194/tcd-5-3479-2011
Abstract: In order to monitor the changes of the glaciers in the Gongga Mountain region on the south-eastern margin of the Qinghai-Tibetan Plateau, 74 monsoonal temperate glaciers were investigated by comparing the Chinese Glacier Inventory (CGI), recorded in the 1960s, with Landsat MSS in 1974, Landsat TM in 1989, 1994, 2005, and ASTER data in 2009. The remote sensing data have been applied to map the glacier outline by threshold ratio images (TM4/TM5). Moreover, the glacier outlines were verified by GPS survey on four large glaciers (Hailuogou, Mozigou, Yanzigou, and Dagongba) in 2009. The results show that the area dominated by the 74 glaciers has shrunk by 11.3 % (29.2 km2) from 1966 to 2009. Glacier area on the eastern and western slope of the Gongga Mountains decreased by 14.1 km2 (5.5 % in 1966) and 15.1 km2 (5.9 % in 1966), respectively. The loss in glacier area and length is respectively 0.8 km2 and 1146.4 m (26.7 m yr 1) for the Hailuogou glacier, 2.1 km2 and 501.8 m (11.7 m yr 1) for the Mozigou Glacier, 0.8 km2 and 724.8 m (16.9 m yr 1) for the Yanzigou Glacier, and 2.4 km2 and 1002.3 m (23.3 m yr 1) for the Dagongba Glacier. Decades of climate records obtained from three meteorological stations in the Gongga Mountains were analyzed to evaluate the impact of the temperature and precipitation on glacier retreat. During 1966–2009, the mean annual temperature over the eastern and western slope of the Gongga Mountains has been increasing by 0.21 °C/10 yr and 0.13 °C/10 yr, respectively. Moreover, it was stable in the mean annual precipitation. This evidence indicates that the warming of the climate is probably responsible for the glacier retreat in the study region.
Elemental composition of aerosols collected in the glacier area on Nyainqêntanglha Range, Tibetan Plateau, during summer monsoon season
ChaoLiu Li,ShiChang Kang,ZhiYuan Cong
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-0445-0
Abstract: In order to investigate the elemental composition in atmospheric aerosols and its sources in the glacier area over the Tibetan Plateau (TP), seven totally suspended particle samples were collected continuously at the col of the Zhadang glacier (30°28′N, 90°39′E, 5800 m a.s.l.), Nyainqêntanglha Range, southern TP, from June to October 2006. Twenty-seven elements (Li, Be, B, Na, Mg, Al, K, Ca, Sc, Ti, V, Fe, Mn, Zn, Ga, As, Rb, Sr, Y, Cd, Cs, Ba, Tl, Pb, Bi, Th, U) were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The result indicates that the concentrations of most elements (especially crustal elements) are lower than values at the Nam Co Station during the same period of 2005, and also much lower than other sites in the TP such as Wudaoliang and Waliguan. This suggests that elemental compositions of aerosols in the Zhadang glacier area may represent the background levels of the middle/upper troposphere over the TP. Crustal enrichment factors (EFs) reveal that several elements (e.g. B, Zn, As, Cd, Pb and Bi) may have anthropogenic sources. The southern TP is mainly influenced by the summer Indian monsoon during the sampling period. Backward air mass trajectory analysis suggests that air masses in the region may originate from South Asia. Therefore, anthropogenic pollutants from South Asia may be transported by the summer Indian monsoon to the region which clearly affects the atmospheric environment in the southern TP during the summer monsoon season.
The response of lake-glacier variations to climate change in Nam Co Catchment, central Tibetan Plateau, during 1970–2000

Yanhong Wu,Liping Zhu,

地理学报(英文版) , 2008,
Abstract: 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.
The response of lake-glacier variations to climate change in Nam Co Catchment, central Tibetan Plateau, during 1970–2000

WU Yanhong,ZHU Liping,

地理学报 , 2008,
Abstract: 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.
Regional Characteristics of Ion Concentration in Glacial Snowpits over the Tibetan Plateau and Source Analysis
青藏高原冰川雪坑中离子浓度的区域特征及来源分析

WU Xiao-bo,LI Quan-lian,WANG Ning-lian,PU Jian-chen,HE Jian-qiao,ZHANG Chun-wen,
武小波
,李全莲,王宁练,蒲健辰,贺建桥,张春文

环境科学 , 2011,
Abstract: The characteristics of ion concentration were studied in snowpit samples collected from the GRHK glacier, the XDKMD glacier and the YZF glacier over the Tibetan Plateau. Samples of snowpits in these three glaciers were analyzed by ion chromatography and ion sources were also explored by correlation analysis. The results indicated that the concentration of Ca2+, Mg2+, Na+, Cl- and SO2-4 increased from the GRHK glacier to the XDKMD glacier and to the YZF glacier, suggesting that the terrestrial matter were major origin from the south to north over the Tibetan Plateau. The concentration of Cl-, Na+ and SO2-4 in YZF glacier was higher by many times than GRHK glacier and XDKMD glacier, Perhaps mainly come from the evaporation of salt lake and the weather of mineral salts in the Qaidam Basin.The sources of NO-3, K+ and NH+4 were complicated and it is not obvious for the indication of environment.
The footprint of Asian monsoon dynamics in the mass and energy balance of a Tibetan glacier  [PDF]
T. M?lg,F. Maussion,W. Yang,D. Scherer
The Cryosphere , 2012, DOI: 10.5194/tc-6-1445-2012
Abstract: Determinations of glacier-wide mass and energy balance are still scarce for the remote mountains of the Tibetan Plateau, where field measurements are challenging. Here we run and evaluate a physical, distributed mass balance model for Zhadang Glacier (central Tibet, 30° N) based on in-situ measurements over 2009–2011 and an uncertainty estimate by Monte Carlo and ensemble strategies. The model application aims to provide the first quantification of how the Indian Summer Monsoon (ISM) impacts an entire glacier over the various stages of the monsoon's annual cycle. We find a strong and systematic ISM footprint on the interannual scale. Early (late) monsoon onset causes higher (lower) accumulation, and reduces (increases) the available energy for ablation primarily through changes in absorbed shortwave radiation. By contrast, only a weak footprint exists in the ISM cessation phase. Most striking though is the core monsoon season: local mass and energy balance variability is fully decoupled from the active/break cycle that defines large-scale atmospheric variability during the ISM. Our results demonstrate quantitatively that monsoon onset strongly affects the ablation season of glaciers in Tibet. However, we find no direct ISM impact on the glacier in the main monsoon season, which has not been acknowledged so far. This result also adds cryospheric evidence that, once the monsoon is in full swing, regional atmospheric variability prevails on the Tibetan Plateau in summer.
The footprint of Asian monsoon dynamics in the mass and energy balance of a Tibetan glacier  [PDF]
T. M?lg,F. Maussion,W. Yang,D. Scherer
The Cryosphere Discussions , 2012, DOI: 10.5194/tcd-6-3243-2012
Abstract: Determinations of glacier-wide mass and energy balance are still scarce for the remote mountains of the Tibetan Plateau, where field measurements are challenging. Here we run and evaluate a physical, distributed mass balance model for Zhadang glacier (central Tibet, 30° N), based on in-situ measurements over 2009–2011 and an uncertainty estimate by Monte Carlo and ensemble strategies. The model application aims to provide the first quantification of how the Indian Summer Monsoon (ISM) impacts an entire glacier over the various stages of the monsoon's annual cycle. We find a strong and systematic ISM footprint on the interannual scale. Early (late) monsoon onset causes higher (lower) accumulation, and reduces (increases) the available energy for ablation primarily through changes in absorbed shortwave radiation. By contrast, only a weak footprint exists in the ISM cessation phase. Most striking though is the core monsoon season: local mass and energy balance variability is fully decoupled from the active/break cycle that defines large-scale atmospheric variability during the ISM. Our results demonstrate quantitatively that monsoon onset strongly affects the ablation season of glaciers in Tibet. However, we find no direct ISM impact on the glacier in the main monsoon season, which has not been acknowledged so far. This result also adds cryospheric evidence that regional modification of the large-scale monsoon flow prevails on the Tibetan Plateau in summer.
Modeling sensitivity study of the possible impact of snow and glaciers developing over Tibetan Plateau on Holocene African-Asian summer monsoon climate  [PDF]
L. Jin,Y. Peng,F. Chen,A. Ganopolski
Climate of the Past Discussions , 2008,
Abstract: The impacts of various scenarios of snow and glaciers developing over the Tibetan Plateau on climate change in Afro-Asian monsoon region and other regions during the Holocene (9 kyr BP–0 kyr BP) are studied by using the coupled climate model of intermediate complexity, CLIMBER-2. The simulations show that the imposed snow and glaciers over the Tibetan Plateau in the mid-Holocene induce global summer temperature decreases, especially in the northern parts of Europe, Asia, and North America. At the same time, with the imposed snow and glaciers, summer precipitation decreases strongly in North Africa and South Asia as well as northeastern China, while it increases in Southeast Asia and the Mediterranean. For the whole period of Holocene (9 kyr BP–0 kyr BP), the response of vegetation cover to the imposed snow and glaciers cover over the Tibetan Plateau is not synchronous in South Asia and in North Africa, showing an earlier and a more rapid decrease in vegetation cover in North Africa from 9 to 6 kyr BP while it has only minor influence on that in South Asia until 5 kyr BP. Imposed gradually increased snow and glacier cover over the Tibetan Plateau causes temperature increases in South Asia and it decreases in North Africa and Southeast Asia during 6 kyr BP to 0 kyr BP. The precipitation decreases rapidly in North Africa and South Asia while it decreases slowly or unchanged during 6 kyr BP to 0 kyr BP with imposed snow and glacier cover over the Tibetan Plateau. The different scenarios of snow and glacier developing over the Tibetan Plateau would result in differences in variation of temperature, precipitation and vegetation cover in North Africa, South Asia and Southeast Asia. The model results show that the response of climate change in African-Asian monsoon region to snow and glacier cover over the Tibetan Plateau is in the way that the snow and glaciers amplify the effect of vegetation feedback and, hence, further amplify orbital forcing.
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