Journal articles on the topic 'Glaciers – Tibet, Plateau of'
To see the other types of publications on this topic, follow the link: Glaciers – Tibet, Plateau of.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Glaciers – Tibet, Plateau of.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Zeng, Junze, Junfeng Xie, Ren Liu, Fan Mo, and Xiaomeng Yang. "Research on Glacier Elevation Variability in the Qilian Mountains of the Qinghai-Tibet Plateau Based on Topographic Correction by Pyramid Registration." Remote Sensing 15, no. 1 (December 22, 2022): 62. http://dx.doi.org/10.3390/rs15010062.
Full textAbstract:
As the ‘Third Pole’ of the world, the Qinghai-Tibet Plateau is also known as the Asian Water Tower. The glaciers covering its surface can reflect changes in the global climate and ecological environment. Therefore, the critical need for accurate information regarding the elevation changes of the glaciers on the Qinghai-Tibet Plateau is self-evident. Here we present a method for monitoring the elevation change of the glaciers on the Qinghai-Tibet Plateau that is based on pyramid registration and terrain correction techniques. The registration results show that the average elevation difference in the stable area has been improved to a considerable extent, at least 70%. The elevation difference after registration obeys a Gaussian distribution with a mean of 0. In this study, glaciers in the Qilian Mountains of the Qinghai-Tibet Plateau were used as the experimental objects, and the changes in glacier elevation in the region were monitored over the past three years. The results show that from 2019 to 2021, the glaciers in the western Qilian Mountains thinned significantly, and the glacier elevation change rate was –0.99 ± 0.34 m/year. The changes in glaciers in the southwest and north were relatively minor, with change rates of 0.09 ± 0.94 m/year and –0.08 ± 0.79 m/year, respectively. The change rates of the two glaciers in the middle were 0.74 ± 0.84 m/year and –0.16 ± 0.85 m/year, and the glacier change rate in the northeast was –0.27 ± 0.77 m/year. Finally, combined with meteorological data analysis, it is concluded that the change in glacier elevation is primarily affected by temperature and precipitation. Among these, precipitation accounts for the dominant factor impacting glacier elevation change.
2
Wenjing, Zhang. "Identification of glaciers with surge characteristics on the Tibetan Plateau." Annals of Glaciology 16 (1992): 168–72. http://dx.doi.org/10.3189/1992aog16-1-168-172.
Full textAbstract:
Investigations of Zelunglung and Midui Glaciers in southeast Tibet, China, indicate that they have some characteristics of surge-type glaciers. There have been two extraordinary movements of Zelunglung Glacier, one in 1950 and one in 1968. A collapse of the terminus area took place in 1984. Midui Glacier experienced extraordinary movements about 55 years ago and also in 1988. During these events, the glacier termini reached moraines formed during neoglaciation and the Little Ice Age. The advances of the two glaciers are not related to climate variation. The glaciers caused serious disasters with loss of life and property, and disruption of transportation corridors.
3
Wenjing, Zhang. "Identification of glaciers with surge characteristics on the Tibetan Plateau." Annals of Glaciology 16 (1992): 168–72. http://dx.doi.org/10.1017/s0260305500005012.
Full textAbstract:
Investigations of Zelunglung and Midui Glaciers in southeast Tibet, China, indicate that they have some characteristics of surge-type glaciers. There have been two extraordinary movements of Zelunglung Glacier, one in 1950 and one in 1968. A collapse of the terminus area took place in 1984. Midui Glacier experienced extraordinary movements about 55 years ago and also in 1988. During these events, the glacier termini reached moraines formed during neoglaciation and the Little Ice Age. The advances of the two glaciers are not related to climate variation. The glaciers caused serious disasters with loss of life and property, and disruption of transportation corridors.
4
Hu, Wentao, and Tandong Yao. "Geometric similarity of the twin collapsed glaciers in the west Tibet." Open Geosciences 13, no. 1 (January 1, 2021): 1463–75. http://dx.doi.org/10.1515/geo-2020-0316.
Full textAbstract:
Abstract Two adjacent glaciers collapsed consecutively in the Western Xizang Autonomous Region, China, on July 17 and September 21, 2016, presumably triggered by relatively intensive climate change in this region, leading to massive downstream ice and mud avalanches. After these twin glacier collapses, there have been many researches, which mainly focus on the physical characteristics of these two glaciers while lack the differences between them and the other glaciers. In this study, the geometric features and energy distribution along the glacier centerlines are investigated to identify the differences between these two collapsed glaciers and other glaciers in the western Tibetan Plateau. The anomaly of climate change is presumed to be the trigger of the twin glacier collapses in accordance with existing research results, whereas in this study, the striking geometric similarity between the centerlines of the twin glaciers, which is quantitatively interpreted by the Fréchet distance among the glacier centerlines, unearth some novel mechanisms. The essential point in these new mechanisms is the energy distribution along the glacier centerlines. A hypothesis based on the principle of energy conservation is derived to demonstrate the mechanisms and dynamic processes of the glacier collapses. Furthermore, on the basis of the geometric similarity and energy distribution of the glacier centerlines, a risk assessment of glacier collapse in the western Tibetan Plateau is implemented to facilitate glacier disaster prevention.
5
KE, LINGHONG, XIAOLI DING, LEI ZHANG, JUN HU, C. K. SHUM, and ZHONG LU. "Compiling a new glacier inventory for southeastern Qinghai–Tibet Plateau from Landsat and PALSAR data." Journal of Glaciology 62, no. 233 (May 2, 2016): 579–92. http://dx.doi.org/10.1017/jog.2016.58.
Full textAbstract:
ABSTRACTGlacier change has been recognized as an important climate variable due to its sensitive response to climate change. Although there are a large number of glaciers distributed over the southeastern Qinghai–Tibetan Plateau, the region is poorly represented in glacier databases due to seasonal snow cover and frequent cloud cover. Here, we present an improved glacier inventory for this region by combining Landsat observations acquired over 2011–13 (Landsat 8/OLI and Landsat TM/ETM+), coherence images from Advanced Land Observing Satellite Phased Array type L-band Synthetic Aperture Radar images and the Shuttle Radar Topography Mission (SRTM) DEM. We present a semi-automated scheme for integrating observations from multi-temporal Landsat scenes to mitigate cloud obscuration. Further, the clean-ice observations, together with coherence information, slope constraints, vegetation cover and water classification information extracted from the Landsat scenes, are integrated to determine the debris-covered glacier area. After manual editing, we derive a new glacier inventory containing 6892 glaciers >0.02 km2, covering a total area of 6566 ± 197 km2. This new glacier inventory indicates gross overestimation in glacier area (over 30%) in previously published glacier inventories, and reveals various spatial characteristics of glaciers in the region. Our inventory can be used as a baseline dataset for future studies including glacier change assessment.
6
Zhao, Liyun, Lide Tian, Thomas Zwinger, Ran Ding, Jibiao Zong, Qinghua Ye, and John C. Moore. "Numerical simulations of Gurenhekou glacier on the Tibetan Plateau." Journal of Glaciology 60, no. 219 (2014): 71–82. http://dx.doi.org/10.3189/2014jog13j126.
Full textAbstract:
AbstractWe investigate the impact of climate change on Gurenhekou glacier, southern Tibetan Plateau, which is representative of the tens of thousands of mountain glaciers in the region. We apply a three-dimensional, thermomechanically coupled full-Stokes model to simulate the evolution of the glacier. The steep and rugged bedrock geometry requires use of such a flow model. We parameterize the temperature and surface mass-balance (SMB) uncertainties using nearby automatic weather and meteorological stations, 6 year measured SMB data and an energy-balance model for a nearby glacier. Summer air temperature increased at 0.02 Ka−1 over the past 50 years, and the glacier has retreated at an average rate of 8.3 m a−1. Prognostic simulations suggest an accelerated annual average retreat rate of ~9.1 ma−1 along the central flowline for the next 25 years under continued steady warming. However, regional climate models suggest a marked increase in warming rate over Tibet during the 21st century, and this rate causes about a 0.9 ± 0.3% a−1 loss of glaciated area and 1.1 ± 0.6% a−1 shrinkage of glacier volume. These results, the rather high warming rates predicted and the small sizes of most Tibetan glaciers, suggest that significant numbers of glaciers will be lost in the region during the 21st century.
7
Yang, Liye, Chaoying Zhao, Zhong Lu, Chengsheng Yang, and Qin Zhang. "Three-Dimensional Time Series Movement of the Cuolangma Glaciers, Southern Tibet with Sentinel-1 Imagery." Remote Sensing 12, no. 20 (October 21, 2020): 3466. http://dx.doi.org/10.3390/rs12203466.
Full textAbstract:
Many debris-covered glaciers are broadly distributed across High Mountain Asia and have made a number of contributions to water circulation for Qinghai-Tibet Plateau (QTP). The formation of large supraglacial lakes poses risks for glacier lake outburst floods (GLOFs). Therefore, it is important to monitor the movement of glaciers and to analyze their spatiotemporal characteristics. In this study we take Cuolangma glaciers in the central Himalayas as study targets, where glacier No.1 is a lake-terminating debris-covered glacier and glacier No.2 is a land-terminating debris-covered glacier. The 3D deformation time series is firstly estimated by using the Pixel Offset-Small Baseline Subsets (PO-SBAS) based on the ascending and descending Sentinel-1 datasets spanning from January to December 2018. Then the horizontal and vertical time series displacements are obtained to show their spatiotemporal features. The velocities of glacier No.1 in horizontal and vertical direction were up to 16.0 ± 0.04 m/year and 3.4 ± 0.42 m/year, respectively, and the ones of the glacier No.2 were 12.0 ± 0.07 m/year and 2.0 ± 0.27 m/year, respectively. Next, the correlation between the precipitation and the surface velocity suggests that the glacier velocity does not show a clear association with daily precipitation alone. Finally, the debris-covered glaciers evolution is evaluated which shows that the tongue of the glacier No.1 is wasting away and the transition of glacier No.2 from land-terminating to lake-terminating is a probable scenario in the later period of glacier wastage. This research can significantly serve for glacier multidimensional monitoring and the mitigation of hazardous disaster caused by debris-covered glaciers in the central Himalayas.
8
Zhao, L., L. Tian, T. Zwinger, R. Ding, J. Zong, Q. Ye, and J. C. Moore. "Numerical simulations of Gurenhekou Glacier on the Tibetan Plateau using a full-Stokes ice dynamical model." Cryosphere Discussions 7, no. 1 (January 8, 2013): 145–73. http://dx.doi.org/10.5194/tcd-7-145-2013.
Full textAbstract:
Abstract. We investigate the impact of climate change on a small Tibetan glacier that is representative of the tens of thousands of mountain glaciers in the region. We apply a three-dimensional, thermo-mechanically coupled full-Stokes model to Gurenhekou Glacier located in the southern Tibetan Plateau. The steep and rugged geometry requires use of such a flow model to simulate the dynamical evolution of the glacier. We parameterize the temperature and mass balance using nearby automatic weather stations and an energy balance model for another glacier in the same mountain range. Summer air temperature increased at 0.02 K a−1 over the past 50 yr, and the glacier has retreated at an average rate of 8.3 m a−1. Prognostic simulations suggest an accelerated retreating rate up to 14 m a−1 for the next 50 yr under continued steady warming, which is consistent with observed increased retreat in the last decade. However, regional climate models suggest a marked increase in warming rate over Tibet during the 21st century, and this rate causes about a 1% per year loss of glaciated area and glacier volume. These changes imply that this small glacier will probably disappear in a century. Although Tibetan glaciers are not particularly sensitive to climate warming, the rather high warming rates predicted by regional climate models combined with the small sizes of most Tibetan glaciers suggest that significant numbers of glaciers will be lost in the region during the 21st century.
9
Zou, Fang, Robert Tenzer, and Shuanggen Jin. "Water Storage Variations in Tibet from GRACE, ICESat, and Hydrological Data." Remote Sensing 11, no. 9 (May 9, 2019): 1103. http://dx.doi.org/10.3390/rs11091103.
Full textAbstract:
The monitoring of water storage variations is essential not only for the management of water resources, but also for a better understanding of the impact of climate change on hydrological cycle, particularly in Tibet. In this study, we estimated and analyzed changes of the total water budget on the Tibetan Plateau from the Gravity Recovery And Climate Experiment (GRACE) satellite mission over 15 years prior to 2017. To suppress overall leakage effect of GRACE monthly solutions in Tibet, we applied a forward modeling technique to reconstruct hydrological signals from GRACE data. The results reveal a considerable decrease in the total water budget at an average annual rate of −6.22 ± 1.74 Gt during the period from August 2002 to December 2016. In addition to the secular trend, seasonal variations controlled mainly by annual changes in precipitation were detected, with maxima in September and minima in December. A rising temperature on the plateau is likely a principal factor causing a continuous decline of the total water budget attributed to increase melting of mountain glaciers, permafrost, and snow cover. We also demonstrate that a substantial decrease in the total water budget due to melting of mountain glaciers was partially moderated by the increasing water storage of lakes. This is evident from results of ICESat data for selected major lakes and glaciers. The ICESat results confirm a substantial retreat of mountain glaciers and an increasing trend of major lakes. An increasing volume of lakes is mainly due to an inflow of the meltwater from glaciers and precipitation. Our estimates of the total water budget on the Tibetan Plateau are affected by a hydrological signal from neighboring regions. Probably the most significant are aliasing signals due to ground water depletion in Northwest India and decreasing precipitation in the Eastern Himalayas. Nevertheless, an integral downtrend in the total water budget on the Tibetan Plateau caused by melting of glaciers prevails over the investigated period.
10
Bolch, T., T. Yao, S. Kang, M. F. Buchroithner, D. Scherer, F. Maussion, E. Huintjes, and C. Schneider. "A glacier inventory for the western Nyainqentanglha Range and the Nam Co Basin, Tibet, and glacier changes 1976–2009." Cryosphere 4, no. 3 (September 29, 2010): 419–33. http://dx.doi.org/10.5194/tc-4-419-2010.
Full textAbstract:
Abstract. The western Nyainqentanglha Range is located in the south-eastern centre of the Tibetan Plateau. Its north-western slopes drain into Lake Nam Co. The region is of special interest for glacio-climatological research as it is influenced by both the continental climate of Central Asia and the Indian Monsoon system, and situated at the transition zone between temperate and subcontinental glaciers. A glacier inventory for the whole mountain range was generated for the year around 2001 using automated remote sensing and GIS techniques based on Landsat ETM+ and SRTM3 DEM data. Glacier change analysis was based on data from Hexagon KH-9 and Landsat MSS (both 1976), Metric Camera (1984), and Landsat TM/ETM+ (1991, 2001, 2005, 2009). Manual adjustment was especially necessary for delineating the debris-covered glaciers and the glaciers on the panchromatic Hexagon data. In the years around 2001 the whole mountain range contained about 960 glaciers covering an area of 795.6 ± 22.3 km2 while the ice in the drainage basin of Nam Co covered 198.1 ± 5.6 km2. The median elevation of the glaciers was about 5800 m with the majority terminating around 5600 m. Five glaciers with debris-covered tongues terminated lower than 5200 m. The glacier area decreased by −6.1 ± 3% between 1976 and 2001. This is less than reported in previous studies based on the 1970s topographic maps and Landsat data from 2000. Glaciers continued to shrink during the period 2001–2009. No advancing glaciers were detected. Detailed length measurements for five glaciers indicated a retreat of around 10 m per year (1976–2009). Ice cover is higher south-east of the mountain ridge which reflects the windward direction to the monsoon. The temperature increase during the ablation period was probably the main driver of glacier wastage, but the complex glacier-climate interactions need further investigation.
11
Bolch, T., T. Yao, S. Kang, M. F. Buchroithner, D. Scherer, F. Maussion, E. Huintjes, and C. Schneider. "A glacier inventory for the western Nyainqentanglha Range and Nam Co Basin, Tibet, and glacier changes 1976–2009." Cryosphere Discussions 4, no. 2 (April 1, 2010): 429–67. http://dx.doi.org/10.5194/tcd-4-429-2010.
Full textAbstract:
Abstract. The western Nyainqentanglha Mountain Range is located in the south-eastern centre of the Tibetan Plateau. Its north-western slope drains into Lake Nam Co. The area is of special interest for glacio-climatological research as this region is influenced by both the continental climate of Central Asia and the Indian Monsoon system, and it is situated at the transition zone between temperate and subcontinental glaciers. A glacier inventory for the whole mountain range was generated for the year ~2000 using automated remote sensing and GIS techniques based on Landsat ETM+ and SRTM3 DEM data. The change analysis is based on data from Hexagon KH-9 and Landsat MSS (year 1976), Metric Camera (year 1984), and Landsat TM/ETM+ (1991, 2001, 2005, 2009). Manual adjustment was especially necessary for the panchromatic Hexagon data and for debris-covered glaciers. The whole mountain range contains about 960 glaciers covering an area of 795.6 ± 22.3 km2 while the ice in the drainage basin of Nam Co covers 198.1 ± 5.6 km2. The median elevation of the glaciers is ~5800 m a with the majority terminating around 5600 m. Five glaciers with debris-covered tongues terminate lower than 5200 m. The glacier area decreased between 1976 and 2001 by about 6 ± 3%, which is less than presented in previous studies based on topographic maps from the 1970s and Landsat data from 2000. Glaciers continued to shrink during the period 2001–2009. No advancing glaciers were detected. Detailed length measurements for five glaciers indicate a retreat of the tongues of around 10 m per year (1976–2009) with higher absolute but lower relative values for the larger glaciers.
12
Li, Jia, Yunyang Gu, Lixin Wu, Lei Guo, Haodong Xu, and Zelang Miao. "Changes in Glaciers and Glacial Lakes in the Bosula Mountain Range, Southeast Tibet, over the past Two Decades." Remote Sensing 14, no. 15 (August 6, 2022): 3792. http://dx.doi.org/10.3390/rs14153792.
Full textAbstract:
Glaciers and glacial lakes in the Bosula Mountain Range need special attention, because their instability may cause disastrous consequences to the downstream settlements and the Sichuan-Tibet Road. The latter is a pivotal traffic line in the Southeast Tibetan Plateau. In order to investigate the state of glaciers and glacial lakes in the Bosula Mountain Range, we estimated the changes in glacier/glacial lake boundaries, glacier surface elevation, and glacier flow velocity between 2000 and 2021 based on multisource remote sensing data. Our results showed that, from the period 2000–2013 to the period 2013–2021, the average shrinking rate of glacier area increased from 0.99 km2/a to 1.74 km2/a, and the average expanding rate of glacial lake area increased from 0.04 km2/a to 0.06 km2/a. From the period 1990–2011 to the period 2015–2019, the average thinning rate of glaciers increased from 0.83 m/a to 1.58 m/a. These results indicate the Bosula Mountain Range is one of the fastest melting glacierized regions in the High Mountain Asia, and the factors that account for this may include quick temperature rise, abundant summer rainfall, and thin debris cover. In spite of strong ice melting, the observed changes in glacier boundaries, surface elevation, and flow velocity show no sign of surge activity, and the frequency of glacier lake outburst has not increased since 1989. Currently, three proglacial lakes that expanded quickly during 2000–2021 are now prominent hazards. They are directly threatened by accidental ice calving and ice avalanche, and their outburst could cause considerable damage to the downstream settlements and the Sichuan-Tibet Road.
13
Wang, Rongjun, Yongjian Ding, Donghui Shangguan, Wanqin Guo, Qiudong Zhao, Yaojun Li, and Miao Song. "Influence of Topographic Shading on the Mass Balance of the High Mountain Asia Glaciers." Remote Sensing 14, no. 7 (March 24, 2022): 1576. http://dx.doi.org/10.3390/rs14071576.
Full textAbstract:
Most studies attribute the glacier mass balance within High Mountain Asia (HMA) to climate change, ignoring the influence of its complex terrain. Knowledge of the influence of this complex terrain is crucial for understanding the spatial variability in its mass balance. However, there is a lack of any systematic assessment of this influence across HMA. Therefore, in this study, we used the glacier outlines and raster data (SRTM DEM, slope and aspect) to calculate the topographic shading of all 97,965 glaciers within HMA during the ablation period, which is regarded as a major index of the influence of complex terrain on the mass balance. The results showed that 27.19% of HMA glacier area was subjected to topographic shading, and regional differences were significant with respect to both their altitudinal and spatial distributions. The topographic shading contributed to the protection of the smallest glaciers from solar illumination. Furthermore, we found a significant correlation between the topographic shading and mass balance in these small north-facing glaciers. However, these small glaciers were most prevalent in the north-facing orientation, especially in West Kunlun, East Kunlun, Inner Tibet Plateau and Qilian Shan, where shading was found to increase with decreases in the glacier area. This indicates that complex terrain can affect the spatial distribution of the mass balance by altering the solar illumination pattern.
14
Mölg, T., F. Maussion, W. Yang, and D. Scherer. "The footprint of Asian monsoon dynamics in the mass and energy balance of a Tibetan glacier." Cryosphere Discussions 6, no. 4 (August 8, 2012): 3243–86. http://dx.doi.org/10.5194/tcd-6-3243-2012.
Full textAbstract:
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.
15
Mölg, T., F. Maussion, W. Yang, and D. Scherer. "The footprint of Asian monsoon dynamics in the mass and energy balance of a Tibetan glacier." Cryosphere 6, no. 6 (December 6, 2012): 1445–61. http://dx.doi.org/10.5194/tc-6-1445-2012.
Full textAbstract:
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.
16
Yafeng, Shi, and Ren Jiawen. "Glacier Recession and Lake Shrinkage Indicating a Climatic Warming and Drying Trend in Central Asia." Annals of Glaciology 14 (1990): 261–65. http://dx.doi.org/10.3189/s0260305500008715.
Full textAbstract:
Mass balance observations on Urumqi River No. 1 Glacier and Tuyuksu Glacier in Tianshan show a large deficit during the 1980s as compared to the decades before. The Qinghai Lake in northeastern Qinghai-Xizang (Tibet) Plateau and the Issyk-kul Lake in Soviet Tianshan have been continuously shrinking during the past few centuries. Since the maximum of the Little Ice Age which occurred mainly in the 18th century, glaciers have decreased in area by about 44% in the Urumqi valley. These data and other evidence from glaciers, lakes, etc. clearly indicate that the climatic warming and drying tendency grows stronger in this century and will possibly persist to the early decades of the next century. The growing greenhouse effect due to the increase of CO2 and other related gases will enhance this tendency in the near future. However, should the high temperature period of the early and middle Holocene reappear, the climate would become humid.
17
Yafeng, Shi, and Ren Jiawen. "Glacier Recession and Lake Shrinkage Indicating a Climatic Warming and Drying Trend in Central Asia." Annals of Glaciology 14 (1990): 261–65. http://dx.doi.org/10.1017/s0260305500008715.
Full textAbstract:
Mass balance observations on Urumqi River No. 1 Glacier and Tuyuksu Glacier in Tianshan show a large deficit during the 1980s as compared to the decades before. The Qinghai Lake in northeastern Qinghai-Xizang (Tibet) Plateau and the Issyk-kul Lake in Soviet Tianshan have been continuously shrinking during the past few centuries. Since the maximum of the Little Ice Age which occurred mainly in the 18th century, glaciers have decreased in area by about 44% in the Urumqi valley. These data and other evidence from glaciers, lakes, etc. clearly indicate that the climatic warming and drying tendency grows stronger in this century and will possibly persist to the early decades of the next century. The growing greenhouse effect due to the increase of CO2 and other related gases will enhance this tendency in the near future. However, should the high temperature period of the early and middle Holocene reappear, the climate would become humid.
18
Lu, Xin, and Guang-mei Zheng. "Why do eared-pheasants of the eastern Qinghai-Tibet plateau show so much morphological variation?" Bird Conservation International 10, no. 4 (December 2000): 305–9. http://dx.doi.org/10.1017/s0959270900000253.
Full textAbstract:
It is known that White Eared-pheasants Crossoptilon crossoptilon drouyni interbreed widely with Tibetan Eared-pheasants C. harmani at the boundary of their ranges. A new hybrid zone has been found recently in eastern Tibet, far away from the boundary of the parental species' ranges. Based on ecological observations of eared-pheasants and the geographical history and pattern of modern glaciers, we have attributed the complex morphological variation of eared-pheasants and the high biodiversity of the eastern Qinghai-Tibet plateau to its varied geography.
19
Zhou, Shuaibo, Zhangli Sun, and Peijun Sun. "Rapid Glacier Shrinkage in the Gongga Mountains in the Last 27 Years." Remote Sensing 14, no. 21 (October 27, 2022): 5397. http://dx.doi.org/10.3390/rs14215397.
Full textAbstract:
Glaciers are an important part of the cryosphere and important reservoirs of fresh water on Earth. Glaciers in the Gongga Mountains, located in the southeastern Tibetan Plateau, have been experiencing dramatic changes and substantially shrinking over the past two decades. We analyzed the glacier change over the Gongga Mountains using the Landsat data from 1994 to 2021 (interval of 4 or 5 years), with Gaofen-1 (GF-1) data to evaluate the uncertainty. The glacier shrinkage under different terrain conditions, including altitudes, slope, and slope direction, was further explored. Finally, we evaluated the response of glacier shrinkage to climate change using precipitation and temperature data for nearly 30 years. Results show that the glaciers in the Gongga Mountains are experiencing an accelerating ablation, with a glacier area of ~240 km2 in 1994 and ~212 km2 in 2021 (an average annual shrinkage rate of 1.04 km2/a). The shrinkage mainly occurs in areas with altitudes of 5000–5300 m and a slope of 30–40°. Moreover, the shrinkage is strongly related to the recent warming of the climate, with the warming rate being 0.19 °C/10a, while precipitation remains almost constant during 1978–2019. The results provide a scientific basis for water resources management, ecological environmental protection, and natural disaster protection in southeast Tibet for decision making.
20
Zhang, Ruixiong, Yuhang Wang, Qiusheng He, Laiguo Chen, Yuzhong Zhang, Hang Qu, Charles Smeltzer, et al. "Enhanced trans-Himalaya pollution transport to the Tibetan Plateau by cut-off low systems." Atmospheric Chemistry and Physics 17, no. 4 (February 28, 2017): 3083–95. http://dx.doi.org/10.5194/acp-17-3083-2017.
Full textAbstract:
Abstract. Long-range transport followed by deposition of black carbon on glaciers of Tibet is one of the key issues of climate research as it induces changes on radiative forcing and subsequently impacting the melting of glaciers. The transport mechanism, however, is not well understood. In this study, we use short-lived reactive aromatics as proxies to diagnose transport of pollutants to Tibet. In situ observations of short-lived reactive aromatics across the Tibetan Plateau are analyzed using a regional chemistry and transport model. The model performance using the current emission inventories over the region is poor due to problems in the inventories and model transport. Top-down emissions constrained by satellite observations of glyoxal are a factor of 2–6 higher than the a priori emissions over the industrialized Indo-Gangetic Plain. Using the top-down emissions, agreement between model simulations and surface observations of aromatics improves. We find enhancements of reactive aromatics over Tibet by a factor of 6 on average due to rapid transport from India and nearby regions during the presence of a high-altitude cut-off low system. Our results suggest that the cut-off low system is a major pathway for long-range transport of pollutants such as black carbon. The modeling analysis reveals that even the state-of-the-science high-resolution reanalysis cannot simulate this cut-off low system accurately, which probably explains in part the underestimation of black carbon deposition over Tibet in previous modeling studies. Another model deficiency of underestimating pollution transport from the south is due to the complexity of terrain, leading to enhanced transport. It is therefore challenging for coarse-resolution global climate models to properly represent the effects of long-range transport of pollutants on the Tibetan environment and the subsequent consequence for regional climate forcing.
21
Ye, Qinghua, Liping Zhu, Hongxing Zheng, Renji Naruse, Xueqin Zhang, and Shichang Kang. "Glacier and lake variations in the Yamzhog Yumco basin, southern Tibetan Plateau, from 1980 to 2000 using remote-sensing and GIS technologies." Journal of Glaciology 53, no. 183 (2007): 673–76. http://dx.doi.org/10.3189/002214307784409261.
Full textAbstract:
Glacier and lake variations in the Yamzhog Yumco basin in southern Tibet were studied by integrating series of spatial data from topographic maps and Landsat images at three different times: 1980, 1988/90 and 2000. The results indicate that the total glacier area has decreased from 218 km2 in 1980 to 215 km2 in 2000, a total reduction of 3 km2 (i.e. a 1.5% decrease). Glacier recession rates were clearly larger in the 1990s than the 1980s due to the warmer climate. The total lake area decreased by about 67 km2 during 1980–90 and increased by 32 km2 during 1990–2000. It is suggested that change of lake area in the basin was rapid and most likely caused primarily by the change in precipitation and evaporation in the basin, and secondarily by the increased water supply from melting glaciers.
22
Ye, Qinghua, Shichang Kang, Feng Chen, and Jinghua Wang. "Monitoring glacier variations on Geladandong mountain, central Tibetan Plateau, from 1969 to 2002 using remote-sensing and GIS technologies." Journal of Glaciology 52, no. 179 (2006): 537–45. http://dx.doi.org/10.3189/172756506781828359.
Full textAbstract:
AbstractUsing Geographical Information System (GIS) and remote-sensing technologies, we describe quantitative measurements of glacier variations in the Geladandong mountain region of central Tibet. Data from Landsat images at three different times, 1973–76, 1992 and 2002, are compared with glacier areas digitized from a topographic map based on aerial photographs taken in 1969. We find that while some glaciers have advanced during the past 30 years, others have retreated. The area of retreat is much larger than that of advance. The total glacier area has decreased from 889km2 in 1969 to 847km2 in 2002, a reduction of almost 43 km2 (i.e. 4.8% decrease, or an average of 1.29km2 a–1). The variation of glacier area in the Geladandong mountain region is not as large as in other regions within the Tibetan Plateau. Glacier areas decreased 4.7km2 (i.e. an average of 0.68km2 a–1) during 1969–76, 15.4km2 (0.96km2 a–1) during 1976–92, and 22.4km2 (2.24km2 a–1) during 1992–2002, suggesting accelerated glacier retreat in recent years. The recession rates of glacier termini also increased. It is likely that the increase in summer air temperature is the major reason for glacier shrinkage in the Geladandong mountain region.
23
Shi, Junchao, Massimo Menenti, and Roderik Lindenbergh. "Parameterization of Surface Roughness Based on ICESat/GLAS Full Waveforms: A Case Study on the Tibetan Plateau." Journal of Hydrometeorology 14, no. 4 (August 1, 2013): 1278–92. http://dx.doi.org/10.1175/jhm-d-12-0130.1.
Full textAbstract:
Abstract Glaciers in the Tibetan mountains are expected to be sensitive to turbulent sensible and latent heat fluxes. One of the most significant factors of the energy exchange between the atmospheric boundary layer and the glacier is the roughness of the glacier surface. However, methods to parameterize this roughness for glacier surfaces in remote regions are not well known. In this paper, the authors use the data acquired by Ice, Cloud, and Land Elevation Satellite (ICESat)/Geoscience Laser Altimeter System (GLAS) laser altimetry from February 2003 to November 2004 along several tracks over glaciers of the Nyainqêntanglha range in central Tibet. The authors make a study of the waveforms measured by the ICESat/GLAS laser system over mountainous and glacial areas. The surface characteristics are evaluated within laser footprints over the glacier outlines based on the glaciological inventory of the Tibetan Plateau constructed by the Cold and Arid Regions Environmental and Engineering Research Institute (CAREERI), Chinese Academy of Sciences. For this purpose, the authors extract waveform parameters: the waveform width, the number of modes, and the RMS width of the waveform. These parameters are compared with surface slope and roughness obtained from the Advanced Spaceborne Thermal Emission and Reflection Radar (ASTER) Global Digital Elevation Model (GDEM). Through this analysis, the impact of morphology on the returned laser waveform is shown for the Nyainqêntanglha range. The roughness and the slope of the surface can be quite significant and may contribute from several meters to tens of meters to the pulse extent. The waveform analysis results indicate that the received waveforms are capable representations of surface relief within the GLAS footprints.
24
Wang, Chao, Qiong Gao, and Mei Yu. "Quantifying Trends of Land Change in Qinghai-Tibet Plateau during 2001–2015." Remote Sensing 11, no. 20 (October 20, 2019): 2435. http://dx.doi.org/10.3390/rs11202435.
Full textAbstract:
The Qinghai-Tibet Plateau (QTP) is among the most sensitive ecosystems to changes in global climate and human activities, and quantifying its consequent change in land-cover land-use (LCLU) is vital for assessing the responses and feedbacks of alpine ecosystems to global climate changes. In this study, we first classified annual LCLU maps from 2001–2015 in QTP from MODIS satellite images, then analyzed the patterns of regional hotspots with significant land changes across QTP, and finally, associated these trends in land change with climate forcing and human activities. The pattern of land changes suggested that forests and closed shrublands experienced substantial expansions in the southeastern mountainous region during 2001–2015 with the expansion of massive meadow loss. Agricultural land abandonment and the conversion by conservation policies existed in QTP, and the newly-reclaimed agricultural land partially offset the loss with the resulting net change of −5.1%. Although the urban area only expanded 586 km2, mainly at the expense of agricultural land, its rate of change was the largest (41.2%). Surface water exhibited a large expansion of 5866 km2 (10.2%) in the endorheic basins, while mountain glaciers retreated 8894 km2 (−3.4%) mainly in the southern and southeastern QTP. Warming and the implementation of conservation policies might promote the shrub encroachment into grasslands and forest recovery in the southeastern plateau. While increased precipitation might contribute to the expansion of surface water in the endorheic basins, warming melts the glaciers in the south and southeast and complicates the hydrological service in the region. The substantial changes in land-cover reveal the high sensitivity of QTP to changes in climate and human activities. Rational policies for conservation might mitigate the adverse impacts to maintain essential services provided by the important alpine ecosystems.
25
Aizen, Vladimir B., Elena M. Aizen, Daniel R. Joswiak, Koji Fujita, Nozomu Takeuchi, and Stanislav A. Nikitin. "Climatic and atmospheric circulation pattern variability from ice-core isotope/geochemistry records (Altai, Tien Shan and Tibet)." Annals of Glaciology 43 (2006): 49–60. http://dx.doi.org/10.3189/172756406781812078.
Full textAbstract:
AbstractSeveral firn/ice cores were recovered from the Siberian Altai (Belukha plateau), central Tien Shan (Inilchek glacier) and the Tibetan Plateau (Zuoqiupu glacier, Bomi) from 1998 to 2003. The comparison analyses of stable-isotope/geochemistry records obtained from these firn/ice cores identified the physical links controlling the climate-related signals at the seasonal-scale variability. The core data related to physical stratigraphy, meteorology and synoptic atmospheric dynamics were the basis for calibration, validation and clustering of the relationships between the firn-/ice-core isotope/ geochemistry and snow accumulation, air temperature and precipitation origin. The mean annual accumulation (in water equivalent) was 106 gcm−2 a−1 at Inilchek glacier, 69 gcm−2 a−1 at Belukha and 196 g cm−2 a−1 at Zuoqiupu. The slopes in regression lines between the δ18O ice-core records and air temperature were found to be positive for the Tien Shan and Altai glaciers and negative for southeastern Tibet, where heavy amounts of isotopically depleted precipitation occur during summer monsoons. The technique of coupling synoptic climatology and meteorological data with δ18O and d-excess in firn-core records was developed to determine climate-related signals and to identify the origin of moisture. In Altai, two-thirds of accumulation from 1984 to 2001 was formed from oceanic precipitation, and the rest of the precipitation was recycled over Aral–Caspian sources. In the Tien Shan, 87% of snow accumulation forms by precipitation originating from the Aral–Caspian closed basin, the eastern Mediterranean and Black Seas, and 13% from the North Atlantic.
26
Zhang, Xiaopeng, Xiang Qin, Chunhai Xu, and Yushuo Liu. "Simulation of Runoff and Glacier Mass Balance and Sensitivity Analysis in a Glacierized Basin, North-Eastern Qinhai-Tibetan Plateau, China." Water 10, no. 9 (September 15, 2018): 1259. http://dx.doi.org/10.3390/w10091259.
Full textAbstract:
Glaciers have been recognized as the most sensitive indicators of climate change. Mountainous areas, with their characteristic snow and glacier cover, have long been recognized as special hydrological environments, receiving above-average amounts of precipitation. The streams originating in the mountains, nourished with distinct seasonal variations, provide water for the populations of the adjacent lowland. Little is known about the effect of climate change on snow and glacier hydrology and glacier mass balance in the Laohugou Glacier Basin (LHGB) over the past 50 years. A study of the glacier basin was performed to quantify the expected impact of climate change on the hydrology in the north-eastern Qinghai-Tibet Plateau. The DEM (Digital Elevation Model) data, daily temperature, daily precipitation, and evaporation data were applied to force the HBV (Hydrologiska Byrans Vattenbalansavdelning)-light conceptual model to simulate runoff depth and glacier mass balance in the historical period (1959–2015). A genetic calibration algorithm approach (GAP method) was used to obtain parameter sets that reproduced observed runoff depth well. The results suggested a drastic increase of the runoff depth from 1995 to 2015 in the Laohugou glacier basin driven by increased temperature. Temperature and precipitation increased by 0.40 °C (10a)−1 and 1.6 mm·a−1 (p < 0.01), respectively, at AWS1 (the automatic weather station at 4192 m a.s.l. near the hydrological station) in the LHGB from 1959 to 2015. The simulated runoff depth increased at 5.7 mm·a−1 (p < 0.01), the glacier mass balance (GMB) of the LHGB was −280.5 mm·a−1, and the overall glacier mass balance was −17.55 m w.e. from 1959 to 2015. The runoff is found to be more sensitive to the variation of temperature than the variation of precipitation. When the glacier area is decreased by 10%, 53%, and 100%, the peak runoff (July) decreased by 20.4%, 54.2%, and 72.3% relative to the baseline, respectively. In the future climate, the function of glaciers in compensating a potential low flow and regulating peak flow will be weakened in the critical months.
27
Jia, Huicong, Fang Chen, and Donghua Pan. "Disaster Chain Analysis of Avalanche and Landslide and the River Blocking Dam of the Yarlung Zangbo River in Milin County of Tibet on 17 and 29 October 2018." International Journal of Environmental Research and Public Health 16, no. 23 (November 26, 2019): 4707. http://dx.doi.org/10.3390/ijerph16234707.
Full textAbstract:
As a “starting zone” and “amplifier” of global climate change, the Qinghai–Tibet Plateau is very responsive to climate change. The global temperature rise has led directly to an acceleration of glacial melting in the plateau and various glacier avalanche disasters have frequently occurred. The landslide caused by glacier avalanches will damage the surrounding environment, causing secondary disasters and a disaster chain effect. Take the disaster chain of the Yarlung Zangbo River at Milin County in Tibet on 17 and 29 October 2018 as an example; a formation mechanical model was proposed. The evolution mechanism for the chain of events is as follows: glacial melt → loose moraine deposit → migration along the steep erosion groove resulting in glacier clastic deposition then debris flow → formation of the dam plug to block the river → the dammed lake. This sequence of events is of great significance for understanding the developmental trends for future avalanches, landslides, and river blocking dam disasters, and for disaster prevention planning and mitigation in the Qinghai–Tibet Plateau.
28
Li, Bo, Hai Yan Liu, Xian Wei Shi, Feng Li, and Tie Ming Yu. "Application of "3S" Technology in Surveying and Mapping in the Glaciers on the Qinghai-Tibet Plateau." Applied Mechanics and Materials 347-350 (August 2013): 3172–76. http://dx.doi.org/10.4028/www.scientific.net/amm.347-350.3172.
Full textAbstract:
Geographic Information System Technology, Global Positioning System Technology, Remote Sensing Technology, collectively known as 3S technology. In the information age, the technology is one of the important technologies for human changes in the Earth's sustainable development research. As the center of the content of the Earth Information Science, along with the surging trend of information technology, it has been a wide range of applications. Through the practical application of 3S technology, this paper maps on the glacier on the Qinghai-Tibet Plateau for a simple exposition.
29
Ma, Rui, Ziyong Sun, Yalu Hu, Qixin Chang, Shuo Wang, Wenle Xing, and Mengyan Ge. "Hydrological connectivity from glaciers to rivers in the Qinghai–Tibet Plateau: roles of suprapermafrost and subpermafrost groundwater." Hydrology and Earth System Sciences 21, no. 9 (September 27, 2017): 4803–23. http://dx.doi.org/10.5194/hess-21-4803-2017.
Full textAbstract:
Abstract. The roles of groundwater flow in the hydrological cycle within the alpine area characterized by permafrost and/or seasonal frost are poorly known. This study explored the role of permafrost in controlling groundwater flow and the hydrological connections between glaciers in high mountains and rivers in the low piedmont plain with respect to hydraulic head, temperature, geochemical and isotopic data, at a representative catchment in the headwater region of the Heihe River, northeastern Qinghai–Tibet Plateau. The results show that the groundwater in the high mountains mainly occurred as suprapermafrost groundwater, while in the moraine and fluvioglacial deposits on the planation surfaces of higher hills, suprapermafrost, intrapermafrost and subpermafrost groundwater cooccurred. Glacier and snow meltwaters were transported from the high mountains to the plain through stream channels, slope surfaces, and supra- and subpermafrost aquifers. Groundwater in the Quaternary aquifer in the piedmont plain was recharged by the lateral inflow from permafrost areas and the stream infiltration and was discharged as baseflow to the stream in the north. Groundwater maintained streamflow over the cold season and significantly contributed to the streamflow during the warm season. Two mechanisms were proposed to contribute to the seasonal variation of aquifer water-conduction capacity: (1) surface drainage through the stream channel during the warm period and (2) subsurface drainage to an artesian aquifer confined by stream icing and seasonal frost during the cold season.
30
Yi, Shuang, Chunqiao Song, Kosuke Heki, Shichang Kang, Qiuyu Wang, and Le Chang. "Satellite-observed monthly glacier and snow mass changes in southeast Tibet: implication for substantial meltwater contribution to the Brahmaputra." Cryosphere 14, no. 7 (July 21, 2020): 2267–81. http://dx.doi.org/10.5194/tc-14-2267-2020.
Full textAbstract:
Abstract. High-Asia glaciers have been observed to be retreating the fastest in the southeastern Tibet Plateau (SETP), where vast numbers of glaciers and amounts of snow feed the streamflow of the Brahmaputra, a transboundary river linking the world's two most populous countries, China and India. However, the low temporal resolutions in previous observations of glacier and snow (GS) mass balance obscured the seasonal accumulation–ablation variations, and their modelling estimates were divergent. Here we use monthly satellite gravimetry observations from August 2002 to June 2017 to estimate GS mass variation in the SETP. We find that the “spring-accumulation-type” glaciers and snow in the SETP reach their maximum in May. This is in stark contrast to seasonal variations in terrestrial water storage, which is controlled by summer precipitation and reaches the maximum in August. These two seasonal variations are mutually orthogonal and can be easily separated in time-variable gravity observations. Our GS mass balance results show a long-term trend of -6.5±0.8 Gt yr−1 (or 0.67±0.08 m w.e. yr−1) and annual mass decreases ranging from −49.3 to −78.3 Gt with an average of -64.5±8.9 Gt in the SETP between August 2002 and June 2017. The contribution of summer meltwater to the Brahmaputra streamflow is estimated to be 51±9 Gt. This result could help to resolve previous divergent modelling estimates and underlines the importance of meltwater to the Brahmaputra streamflow. The high sensitivity between GS melting and temperature on both annual and monthly scales suggests that the Brahmaputra will suffer from not only changes in total annual discharge but also an earlier runoff peak due to ongoing global warming.
31
Liu, Yushuo, Dahe Qin, Zizhen Jin, Yanzhao Li, Liang Xue, and Xiang Qin. "Dynamic Monitoring of Laohugou Glacier No. 12 with a Drone, West Qilian Mountains, West China." Remote Sensing 14, no. 14 (July 9, 2022): 3315. http://dx.doi.org/10.3390/rs14143315.
Full textAbstract:
Laohugou glacier No. 12 (LHG12), located in the northeast of the Qinghai–Tibet Plateau, is the largest valley glacier in the Qilian mountains. Since 1957, LHG12 has shrunk significantly. Due to the limitations of in situ observations, simulations and investigations of LHG12 have higher levels of uncertainty. In this study, consumer-level, low-altitude microdrones were used to conduct repeated photogrammetry at the lower part of LHG12, and a digital orthophoto map (DOM) and a digital surface model (DSM) with a resolution at the centimeter scale were generated, from 2017 to 2021. The dynamic parameters of the glacier were detected by artificial and automatic extraction methods. Using a combination of GNSS and drone-based data, the dynamic process of LHG12 was analyzed. The results show that the terminus of LHG12 has retreated by 194.35 m in total and by 19.44 m a−1 on average during 2008–2021. The differential ablation leading to terminus retreat distance markedly increased during the study period. In 2019–2021, the maximum annual surface velocity was 6.50 cm day−1, and during ablation season, the maximum surface velocity was 13.59 cm day−1, 52.17% higher than it is annually. The surface parameters, motion, and mass balance characteristics of the glacier had significant differences between the west and east branches. The movement in the west branch is faster than it is in the east branch. Because of the extrusion of the two ice flows, there is a region with a faster surface velocity at the ablation area. The ice thickness of LHG12 is decreasing due to intensified ablation, leading to a deceleration in the surface velocity. In large glaciers, this phenomenon is more obvious than it is in small glaciers in the Qilian mountains.
32
Xu, Xia. "Study on Spatial Distribution of Surface Water Resources in Lhasa Based on RS and GIS." Applied Mechanics and Materials 368-370 (August 2013): 417–20. http://dx.doi.org/10.4028/www.scientific.net/amm.368-370.417.
Full textAbstract:
Surface water resources study has vital function for Lhasa and whole Tibet. TM images in 2000 and 2010, GIS and landscape ecological theory are applied to analyze the spatial distribution characteristics of Lhasas surface water resources. The results show: there are 6662 patches in 2000 and 6340 patches in 2010, which means there have disappeared 322 patches, while the area have increased 20.95km2. The lakes class is the main surface water resources with 41.11% in 2000 and 41.03% in 2010. Tibetan Plateau is very sensitive to global cliamte change, espectially in water resouces. The areas of ice and glaciers, forested swamps, shrub swamps have no change. While other kinds of classs area shows increasing trend, especially rivers area, which increased 12.20 km2.
33
Cai, Jiaxin, Xiaowen Wang, Guoxiang Liu, and Bing Yu. "A Comparative Study of Active Rock Glaciers Mapped from Geomorphic- and Kinematic-Based Approaches in Daxue Shan, Southeast Tibetan Plateau." Remote Sensing 13, no. 23 (December 4, 2021): 4931. http://dx.doi.org/10.3390/rs13234931.
Full textAbstract:
Active rock glaciers (ARGs) are important permafrost landforms in alpine regions. Identifying ARGs has mainly relied on visual interpretation of their geomorphic characteristics with optical remote sensing images, while mapping ARGs from their kinematic features has also become popular in recent years. However, a thorough comparison of geomorphic- and kinematic-based inventories of ARGs has not been carried out. In this study, we employed a multi-temporal interferometric synthetic aperture radar (InSAR) technique to derive the mean annual surface displacement velocity over the Daxue Shan, Southeast Tibet Plateau. We then compiled a rock glacier inventory by synergistically interpreting the InSAR-derived surface displacements and geomorphic features based on Google Earth images. Our InSAR-assist kinematic-based inventory (KBI) was further compared with a pre-existing geomorphic-based inventory (GBI) of rock glaciers in Daxue Shan. The results show that our InSAR-assist inventory consists of 344 ARGs, 36% (i.e., 125) more than that derived from the geomorphic-based method (i.e., 251). Only 32 ARGs in the GBI are not included in the KBI. Among the 219 ARGs detected by both approaches, the ones with area differences of more than 20% account for about 32% (i.e., 70 ARGs). The mean downslope velocities of ARGs calculated from InSAR are between 2.8 and 107.4 mm∙a−1. Our comparative analyses show that ARGs mapping from the InSAR-based kinematic approach is more efficient and accurate than the geomorphic-based approach. Nonetheless, the completeness of the InSAR-assist KBI is affected by the SAR data acquisition time, signal decorrelation, geometric distortion of SAR images, and the sensitivity of the InSAR measurement to ground deformation. We suggest that the kinematic-based approach should be utilized in future ARGs-based studies such as regional permafrost distribution assessment and water storage estimates.
34
Zhang, Mi, Yuping Zhao, Fengqiao Liu, and Xubin Pan. "Glacier Dynamics and Water Balance in the Qinghai-Tibet Plateau." Environmental Science & Technology 46, no. 12 (May 31, 2012): 6449–50. http://dx.doi.org/10.1021/es301928p.
Full text
35
Menenti, M., X. Li, J. Wang, H. Vereecken, J. Li, M. Mancini, Q. Liu, et al. "HYDROLOGIC AND CRYOSPHERIC PROCESSES OBSERVED FROM SPACE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-7/W3 (April 30, 2015): 1101–10. http://dx.doi.org/10.5194/isprsarchives-xl-7-w3-1101-2015.
Full textAbstract:
Ten Dragon 3 projects deal with hydrologic and cryosphere processes, with a focus on the Himalayas and Qinghai – Tibet Plateau, but not limited to that. At the 1st Dragon 3 Progress Symposium in 2013 a significant potential for a better and deeper integration appeared very clearly and we worked out an overview of the ten projects identifying specific issues and objectives shared by at least two projects. At the Mid Term Symposium in 2014 a joint session was held over two days. As regards cryospheric processes science highlights covered: Glacier flow velocity by optical and SAR features tracking and InSAR; Patterns in space and time of glacier flow velocity; Mass change estimated with DTM-s and altimetry; Reflectance and LST used to classify glacier surface and understand surface processes, Inventory and changes in the number and area of lakes in the Qinghai – Tibet Plateau 1970, 1990, 2000 and 2010; Deformation of permafrost along the Qinghai – Tibet railway. <br><br> Highlights on hydrologic processes included: Global comparison of SMOS, ASCAT and ERA soil moisture data products; Relative deviations evaluated by climate zone; Soil moisture data products improved with ancillary data; Assimilation of FY - , TRMM and GPM precipitation data products in WRF; Improved algorithm and data products on fractional snow cover; Improvement of MODIS ET with assimilation of LST; TRMM data products evaluated in the Yangtze; Calibration of river basin models using LST; System to calibrate, correct and normalize (spatial, spectral) data collected by imaging spectral radiometers; Integration of data acquired by different sensors, e.g. ET Monitor with optical and microwave (SMOS, FY – 3) data; Hydrological data products used both for forcing and evaluation of Qinghai – Tibet Plateau hydrological model; Wetlands vulnerability assessed through changes in land cover 1987 – 2013; Multi incidence angle and multi – temporal SAR to monitor water extent. In the general session a proposal for a Dragon Water Cycle Initiative was presented.
36
Wang, Weicai, Tandong Yao, and Xiaoxin Yang. "Variations of glacial lakes and glaciers in the Boshula mountain range, southeast Tibet, from the 1970s to 2009." Annals of Glaciology 52, no. 58 (2011): 9–17. http://dx.doi.org/10.3189/172756411797252347.
Full textAbstract:
AbstarctCatastrophic floods originating from glacial lake outbursts have recently become one of the primary natural hazards in the southeastern Tibetan Plateau. Here we report observations of glacial lake expansions and glacier recessions in the Boshula mountain range, southeast Tibet, derived from multitemporal remote-sensing images and digital elevation models during the period from the 1970s to 2009. The area of glacial lakes has expanded from 10.96 ± 0.1 km2 in the 1970s to 10.96±0.1km2 in 2009. Specifically, the area of moraine-dammed lakes has increased by 26.8%. From the 1970s to 2009, the glacierized area in the Boshula mountain range shrank by 12.7% (21.2 km2). Increasing mean summer air temperature was the main cause for the glacier recession and lake expansion from the 1970s to 2001, while the combination of increased summer temperature and decreased summer precipitation led to accelerated glacier recession after 2001. Climate warming and ongoing deglaciation play important roles in the expansion of moraine-dammed lakes, calling for intensified monitoring to properly address the hazard potential in the study area.
37
Wang, Xiaowen, Lin Liu, Yan Hu, Tonghua Wu, Lin Zhao, Qiao Liu, Rui Zhang, Bo Zhang, and Guoxiang Liu. "Multi-decadal geomorphic changes of a low-angle valley glacier in the East Kunlun Mountains: remote sensing observations and detachment hazard assessment." Natural Hazards and Earth System Sciences 21, no. 9 (September 13, 2021): 2791–810. http://dx.doi.org/10.5194/nhess-21-2791-2021.
Full textAbstract:
Abstract. Detachments of large parts of low-angle mountain glaciers in recent years have raised great attention due to their threats to lives and properties downstream. While current studies have mainly focused on post-event analysis, a few opportunities have presented themselves to assess the potential hazards of a glacier prone to detachment. Here we present a comprehensive analysis of the dynamics and runout hazard of a low-angle (∼20∘) valley glacier, close to the Qinghai–Tibet railway and highway, in the East Kunlun Mountains on the Qinghai–Tibet Plateau. The changes in morphology, terminus position, and surface elevation of the glacier between 1975 and 2021 were characterized with a stereo-image pair from the historical KH-9 spy satellite, six digital elevation models (DEMs), and 11 high-resolution images from Planet Labs. The surface flow velocities of the glacier tongue between 2009 and 2020 were also tracked based on cross-correlation of Planet images. Our observations show that the glacier snout has been progressively advancing in the past 4 decades, with a stepwise increase in advance velocity from 4.55±0.46ma-1 between 1975 and 2009 to 30.88±2.36ma-1 between 2015 and 2020. DEM differencing confirms the glacial advance, with surface thinning in the source region and thickening in the tongue. The net volume loss over the glacier tongue was about 11.21±2.66×105 m3 during 1975–2018. Image cross-correlation reveals that the surface flow velocity of the glacier tongue has been increasing in recent years, with the mean velocity below 4800 m more than tripling from 6.3±1.8ma-1 during 2009–2010 to 22.3±3.2ma-1 during 2019–2020. With a combined analysis of the geomorphic, climatic, and hydrologic conditions of the glacier, we suggest that the flow of the glacier tongue is mainly controlled by the glacier geometry, while the presence of an ice-dammed lake and a supraglacial pond implies a hydrological influence as well. Taking the whole glacier and glacier tongue as two endmember avalanche sources, we assessed the potential runout distances of these two scenarios using the angle of reach and the Voellmy–Salm avalanche model. The assessments show that the avalanche of the whole glacier would easily travel a distance that would threaten the safety of the railway. In contrast, the detachment of the glacier tongue would threaten the railway only with a small angle of reach or when employing a low-friction parameter in the Voellmy–Salm modeling.
38
Burbank, Douglas W., and Kang Jian Cheng. "Relative dating of Quaternary moraines, Rongbuk valley, Mount Everest, Tibet: Implications for an ice sheet on the Tibetan Plateau." Quaternary Research 36, no. 1 (July 1991): 1–18. http://dx.doi.org/10.1016/0033-5894(91)90013-u.
Full textAbstract:
AbstractRelative-dating studies applied to high-altitude moraines (5000–5500 m) in the Rongbuk valley on the northern flank of Mt. Everest reveal strong contrasts in the weathering characteristics of the boulders exposed along moraine crests. These differences serve to define three intervals of major Pleistocene glaciation that, on the basis of the degree of weathering, are interpreted to extend back to at least the penultimate glaciation and probably encompass at least one still older glaciation. Either interpretation indicates that some of these moraines are considerably older than their previously assigned ages. The magnitude of equilibrium-line lowering during Neoglacial and late Pleistocene times is calculated to be ca. 50–100 and 350–450 m, respectively. The data described here are incompatible with the recently proposed model (Kuhle, 1987) for large-scale ice-sheet development on the Tibetan Plateau. The reconstructed equilibrium-line lowering in the Everest region is only 30% of that cited in the ice-sheet model. Moreover, the flow patterns and geometry of the former Rongbuk glaciers are in opposition to those proposed by the model. Based on the data from the Everest region, it appears that valley glaciation, rather than ice-sheet growth, characterized the southern margin of the Tibetan Plateau during the middle and late Pleistocene glaciations.
39
Xu, Y., V. Ramanathan, and W. M. Washington. "Observed high-altitude warming and snow cover retreat over Tibet and the Himalayas enhanced by black carbon aerosols." Atmospheric Chemistry and Physics Discussions 15, no. 13 (July 10, 2015): 19079–109. http://dx.doi.org/10.5194/acpd-15-19079-2015.
Full textAbstract:
Abstract. Himalayan mountain glaciers and the snowpack over the Tibetan Plateau provide the headwater of several major rivers in Asia. In-situ observations of snow cover fraction since the 1960s suggest that the snow pack in the region have retreated significantly, accompanied by a surface warming of 2–2.5 °C observed over the peak altitudes (5000 m). Using a high-resolution ocean–atmosphere global climate model and an observationally constrained black carbon (BC) aerosol forcing, we attribute the observed altitude dependence of the warming trends as well as the spatial pattern of reductions in snow depths and snow cover fraction to various anthropogenic factors. At the Tibetan Plateau altitudes, the increase of atmospheric CO2 concentration exerted a warming of 1.7 °C, BC 1.3 °C where as cooling aerosols cause about 0.7 °C cooling, bringing the net simulated warming consistent with the anomalously large observed warming. We therefore conclude that BC together with CO2 has contributed to the snow retreat trends. Especially, BC increase is the major factor in the strong elevation dependence of the observed surface warming. The atmospheric warming by BC as well as its surface darkening of snow are coupled with the positive snow albedo feedbacks to account for the disproportionately large role of BC in high-elevation regions. These findings reveal that BC impact needs to be properly accounted for in future regional climate projections, in particular on high-altitude cryosphere.
40
Xu, Y., V. Ramanathan, and W. M. Washington. "Observed high-altitude warming and snow cover retreat over Tibet and the Himalayas enhanced by black carbon aerosols." Atmospheric Chemistry and Physics 16, no. 3 (February 5, 2016): 1303–15. http://dx.doi.org/10.5194/acp-16-1303-2016.
Full textAbstract:
Abstract. Himalayan mountain glaciers and the snowpack over the Tibetan Plateau provide the headwater of several major rivers in Asia. In situ observations of snow cover extent since the 1960s suggest that the snowpack in the region have retreated significantly, accompanied by a surface warming of 2–2.5 °C observed over the peak altitudes (5000 m). Using a high-resolution ocean–atmosphere global climate model and an observationally constrained black carbon (BC) aerosol forcing, we attribute the observed altitude dependence of the warming trends as well as the spatial pattern of reductions in snow depths and snow cover extent to various anthropogenic factors. At the Tibetan Plateau altitudes, the increase in atmospheric CO2 concentration exerted a warming of 1.7 °C, BC 1.3 °C where as cooling aerosols cause about 0.7 °C cooling, bringing the net simulated warming consistent with the anomalously large observed warming. We therefore conclude that BC together with CO2 has contributed to the snow retreat trends. In particular, BC increase is the major factor in the strong elevation dependence of the observed surface warming. The atmospheric warming by BC as well as its surface darkening of snow is coupled with the positive snow albedo feedbacks to account for the disproportionately large role of BC in high-elevation regions. These findings reveal that BC impact needs to be properly accounted for in future regional climate projections, in particular on high-altitude cryosphere.
41
Zhu, Guofeng, Yuanfeng Liu, Yuanqing He, Tao Pu, Jiafang Li, and Ling Yang. "Variations of chemical features in a monsoon glacier watershed, southeastern Tibet Plateau." Environmental Earth Sciences 74, no. 7 (June 13, 2015): 5793–803. http://dx.doi.org/10.1007/s12665-015-4597-y.
Full text
42
Krause, P., S. Biskop, J. Helmschrot, W. A. Flügel, S. Kang, and T. Gao. "Hydrological system analysis and modelling of the Nam Co basin in Tibet." Advances in Geosciences 27 (August 25, 2010): 29–36. http://dx.doi.org/10.5194/adgeo-27-29-2010.
Full textAbstract:
Abstract. The Tibetan Plateau and the adjacent high mountain regions of the Himalayas play an important role in the global climate dynamic through its impact on the Asian monsoon system, which in turn is impacting the water resources of this extremely vulnerable region. To provide further knowledge about the changing impact of rainfall patterns, spatial and temporal variability of snow cover contribution, amount of snow and ice melt runoff, evapotranspiration as well as dynamics of wetlands and permafrost water balance studies are required. This is of particular importance in terms of global climate change because of a severe gap in the knowledge of the short, mid and long term implications on the hydrological system. This study concentrates on the macroscale catchment of the lake Nam Co, located at 4718 m a.s.l. at the foot of the Nyainqentanglha Mountains in central Tibet (30° N, 90° E). The water balance of the Nam Co basin is dominated by semi-arid climate, snow and ice melt runoff and high evaporation rates due to the high radiation input and the low air humidity. The observed temperature rise, glacier retreat, permafrost decay and lake level increase indicate significant system changes and the high sensitivity of the Tibetan Plateau on global warming. The development of a suitable water balance model and its preliminary application was the main objective of this study. The development was done with the Jena Adaptable Modelling System JAMS along with existing scientific process components of the J2000 module library which were partly further developed to reflect the specific conditions of the high elevation Nam Co basin. The preliminary modelling exercise based on gridded data from a downscaled ECHAM5 data set provided reasonable estimates about the important hydrological water balance components of the Nam Co basin. With the modelling results the observed lake level rise could be reproduced and it could be shown that the runoff from the glaciered areas seems to be the most important component to explain the increasing amount of lake water.
43
Lüthi, Z. L., B. Škerlak, S. W. Kim, A. Lauer, A. Mues, M. Rupakheti, and S. Kang. "Atmospheric brown clouds reach the Tibetan Plateau by crossing the Himalayas." Atmospheric Chemistry and Physics Discussions 14, no. 20 (November 13, 2014): 28105–46. http://dx.doi.org/10.5194/acpd-14-28105-2014.
Full textAbstract:
Abstract. The Himalayas and the Tibetan Plateau region (HTP), despite being a remote and sparsely populated area, is regularly exposed to polluted air masses with significant amounts of aerosols including black carbon. These dark, light-absorbing particles are known to exert a great melting potential on mountain cryospheric reservoirs through albedo reduction and radiative forcing. This study combines the available yet sparse ground-based and satellite data to identify a severe aerosol pollution episode observed simultaneously in central Tibet and on the southern side of the Himalayas during 13–19 March 2009. We detail how polluted air masses such as an atmospheric brown cloud (ABC) over South Asia reached the Tibetan Plateau during this pre-monsoon case study. In order to address the mechanisms of pollution transport in the complex topography of the HTP, air-mass trajectories are calculated using hourly outputs from the high-resolution numerical weather prediction model COSMO. Cross-mountain pollution transport is found to occur to a large extent at elevated tropospheric levels other than just through major river valleys. Lifting and advection of polluted air masses over the great mountain range is enabled by a combination of synoptic and local meteorological settings. Winds over the Indo Gangetic Plain (IGP) are generally weak at lower levels during the event, allowing for accumulation of pollutants. The passing of synoptic-scale troughs leads to south-westerly flow in the middle troposphere over northern and central India. Thus, ABC can build up south of the Himalayas and get carried northwards across the mountain range and onto the Tibetan Plateau as the winds obtain a southerly component. Air masses from the ABC hot-spot of the IGP can reach the high glaciers, which may have serious implications for the cryosphere in the HTP region and for climate on regional to global scales.
44
Sun, Xi-yong, Rui-jiang Zhang, Wei Huang, Ang Sun, Liang-jun Lin, Hong-gen Xu, and De-cai Jiang. "The response between glacier evolution and eco-geological environment on the Qinghai-Tibet Plateau." China Geology 2, no. 1 (2019): 1–7. http://dx.doi.org/10.31035/cg2018078.
Full text
45
Li, Liu, Liu, Li, and Xu. "Greening Implication Inferred from Vegetation Dynamics Interacted with Climate Change and Human Activities over the Southeast Qinghai–Tibet Plateau." Remote Sensing 11, no. 20 (October 18, 2019): 2421. http://dx.doi.org/10.3390/rs11202421.
Full textAbstract:
Vegetation dynamics are sensitive to climate change and human activities, as vegetation interacts with the hydrosphere, atmosphere, and biosphere. The Yarlung Zangbo River (YZR) basin, with the vulnerable ecological environment, has experienced a series of natural disasters since the new millennium. Therefore, in this study, the vegetation dynamic variations and their associated responses to environmental changes in the YZR basin were investigated based on Normalized Difference Vegetation Index (NDVI) and Global Land Data Assimilation System (GLDAS) data from 2000 to 2016. Results showed that (1) the YZR basin showed an obvious vegetation greening process with a significant increase of the growing season NDVI (Zc = 2.31, p < 0.05), which was mainly attributed to the wide greening tendency of the downstream region that accounted for over 50% area of the YZR basin. (2) Regions with significant greening accounted for 25.4% of the basin and were mainly concentrated in the Nyang River and Parlung Tsangpo River sub-basins. On the contrary, the browning regions accounted for <25% of the basin and were mostly distributed in the urbanized cities of the midstream, implying a significant influence of human activities on vegetation greening. (3) The elevation dependency of the vegetation in the YZR basin was significant, showing that the vegetation of the low-altitude regions was better than that of the high-altitude regions. The greening rate exhibited a significantly more complicated relationship with the elevation, which increased with elevated altitude (above 3500 m) and decreased with elevated altitude (below 3500 m). (4) Significantly positive correlations between the growing season NDVI and surface air temperature were detected, which were mainly distributed in the snow-dominated sub-basins, indicating that glaciers and snow melting processes induced by global warming play an important role in vegetation growth. Although basin-wide non-significant negative correlations were found between precipitation and growing season NDVI, positive influences of precipitation on vegetation greening occurred in the arid and semi-arid upstream region. These findings could provide important information for ecological environment protection in the YZR basin and other high mountain regions.
46
Li, Dong-Sheng, Bu-Li Cui, Ying Wang, Bei Xiao, and Bao-Fu Jiang. "Glacier extent changes and possible causes in the Hala Lake Basin of Qinghai-Tibet Plateau." Journal of Mountain Science 16, no. 7 (July 2019): 1571–83. http://dx.doi.org/10.1007/s11629-018-5198-5.
Full text
47
Wang, Rongjun, Yongjian Ding, Donghui Shangguan, Lan Cuo, Qiudong Zhao, Jia Qin, Jing Li, and Miao Song. "Projections of glacier peak water and its timing in the Sanjiangyuan on the Tibet Plateau." Journal of Hydrology: Regional Studies 45 (February 2023): 101313. http://dx.doi.org/10.1016/j.ejrh.2022.101313.
Full text
48
Dahe, Qin, Paul A. Mayewski, Cameron P. Wake, Kang Shichang, Ren Jiawen, Hou Shugui, Yao Tandong, Yang Qinzhao, Jin Zhefan, and Mi Desheng. "Evidence for recent climate change from ice cores in the central Himalaya." Annals of Glaciology 31 (2000): 153–58. http://dx.doi.org/10.3189/172756400781819789.
Full textAbstract:
AbstractComparison of the terminus locations of Rongbuk Glacier, Mount Everest, measured in 1966 and 1997 shows that in the past 30 years the glacier has retreated 170–270 m equivalent to a retreat speed of 5.5–8.7 m a–1 . During summer 1997, a 15 m firn core was recovered from Dasuopu glacier (28°23’ N, 85°44’ E; 7000 m a.s.D on the northwest margin of Xixabangma Feng, Xizang (Tibet). The seasonal variations of δ18O values in the core indicate that monsoon signals are clearly recorded in the glacier. δ18O values are controlled by the amount effect in the monsoon season; more negative δ18O is representative of the monsoon season in snow layers. Analysis of the relationship between ice-core δ18O, sampled from 6500 m a.s.l. on the north side of Mount Everest, and instrumental series representing regional-scale precipitation, atmospheric circulation and temperature suggests a change in the relative influence of these parameters on δ18O since the 1940s. The results of the comparison add to and lengthen the sparse array of instrument data available for the Tibetan (Qinghai-Xizang) Plateau and demonstrate a recent decline in moisture flux for at least the southern part of the plateau. Glacier retreat, associated with a recent increase in temperature in the region, is coincident with this period of decreased moisture flux.
49
Wu, Jinkui, Hongyuan Li, Jiaxin Zhou, Shuya Tai, and Xueliang Wang. "Variation of Runoff and Runoff Components of the Upper Shule River in the Northeastern Qinghai–Tibet Plateau under Climate Change." Water 13, no. 23 (November 26, 2021): 3357. http://dx.doi.org/10.3390/w13233357.
Full textAbstract:
Quantifying the impact of climate change on hydrologic features is essential for the scientific planning, management and sustainable use of water resources in Northwest China. Based on hydrometeorological data and glacier inventory data, the Spatial Processes in Hydrology (SPHY) model was used to simulate the changes of hydrologic processes in the Upper Shule River (USR) from 1971 to 2020, and variations of runoff and runoff components were quantitatively analyzed using the simulations and observations. The results showed that the glacier area has decreased by 21.8% with a reduction rate of 2.06 km2/a. Significant increasing trends in rainfall runoff, glacier runoff (GR) and baseflow indicate there has been a consistent increase in total runoff due to increasing rainfall and glacier melting. The baseflow has made the largest contribution to total runoff, followed by GR, rainfall runoff and snow runoff, with mean annual contributions of 38%, 28%, 18% and 16%, respectively. The annual contribution of glacier and snow runoff to the total runoff shows a decreasing trend with decreasing glacier area and increasing temperature. Any increase of total runoff in the future will depend on an increase of rainfall, which will exacerbate the impact of drought and flood disasters.
50
Wang, Mingguo, Li Yang, Jingjie Li, and Qian Liang. "Hydrochemical Characteristics and Controlling Factors of Surface Water in Upper Nujiang River, Qinghai-Tibet Plateau." Minerals 12, no. 4 (April 17, 2022): 490. http://dx.doi.org/10.3390/min12040490.
Full textAbstract:
Rivers play an essential role in the global matter transport and hydrogeochemical cycle. Hydrogeochemical research is significant to developing and protecting water resources in the Qinghai-Tibet Plateau and its lower reaches. This study aimed to identify the hydrochemical characteristics and controlling factors of Daqu River and Gaqu River in Dingqing County, two tributaries of the upper Nujiang River. This study used spatial analysis, trilinear diagram analysis, and ion ratio analysis of hydrochemical indexes to investigate the hydrochemical characteristics and controlling factors. Results show that Ca2+ and Mg2+, and HCO3− and SO42− are the main cations and anions of these two rivers. HCO3·SO4-Mg·Ca and HCO3·SO4-Ca·Mg are the primary hydrochemical types for the surface water of Daqu and Gaqu Rivers, respectively. The influence of atmospheric precipitation and anthropogenic activities is weak. The carbonated water–rock reaction is the main Ca2+, Mg2+, and HCO3− source, and hot springs act as the primary source of SO42− and supplements Ca2+, Mg2+, and HCO3−. Mg2+ from magnesite dissolution exists in the Daqu River basin. Weak reverse cation exchange occurs in both rivers. Daqu River receives more low-mineralized glacier meltwater along the flow, whereas Gaqu River receives more high-mineralized hot spring water.