By using a degree-day based distributed hydrological model, regimes of glacial runoff from the Koxkar glacier during 2007-2011 are simulated, and variations and characteristics of major hydrological components are dis...By using a degree-day based distributed hydrological model, regimes of glacial runoff from the Koxkar glacier during 2007-2011 are simulated, and variations and characteristics of major hydrological components are discussed. The results show that the meltwater runoff contributes 67.4%, of the proglacial discharge, out of which snowmelt, clean ice melting, buried-ice ablation and ice-cliff backwasting account for 22.4%, 21.9%, 17.9% and 5.3% of the total melt runoff, respectively. Rainfall runoff is significant in mid-latitude glacierized mountain areas like Tianshan and Karakorum. In the Koxkar glacier catchment, about 11.5% of stream water is initiated from liquid precipitation. Spatial distributions for each glacial runoff component reveal the importance of climatic gradients, local topography and morphology on glacial runoff generation, and temporal variations of these components is closely related to the annual cycle of catchment meteorology and glacier storage. Four stages are recognized in the seasonal variations of glacier storage, reflecting changes in meltwater yields, meteorological conditions and drainage systems in the annual hydrological cycle.展开更多
Glaciers in the Shaksgam valley provide important fresh water resources to neighbourhood livelihood. Repeated creation of the glacier inventories is important to assess glacier–climate interactions and to predict fut...Glaciers in the Shaksgam valley provide important fresh water resources to neighbourhood livelihood. Repeated creation of the glacier inventories is important to assess glacier–climate interactions and to predict future runoff from glacierized catchments. For this study, we applied a multi-criteria technique to map the glaciers of the Shaksgam valley of China, using Landsat Thematic Mapper(Landsat TM)(2009) and Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model version two(ASTER GDEM V2) data. The geomorphometric parameters slope, plan, and profile curvature were generated from ASTER GDEM. Then they were organized in similar surface groups using cluster analysis. For accurate mapping of supraglacial debris area, clustering results were combined with a thermal mask generated from the Landsat TM thermal band. The debris-free glaciers were identified using the band ratio(TM band 4/TM band 5) technique. Final vector maps of the glaciers were created using overlay tools in a geographic information system(GIS).Accuracy of the generated glacier outlines was assessed through comparison with glacier outlines based on the Second Chinese Glacier Inventory(SCGI) data and glacier outlines created from high-resolution Google Earth? images of 2009. Glacier areas derived using the proposed approach were 3% less than in the reference datasets. Furthermore, final glacier maps show satisfactory mapping results, but identification of the debris-cover glacier terminus(covered by thick debris layer) is still problematic. Therefore, manual editing was necessary to improve the final glacier maps.展开更多
Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In t...Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun Group of Glaciers(NKGG),were investigated using Landsat satellite data during 2000-2020.Changes in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field observations.The study revealed that the NKGG glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation period.Using the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and 2012.The observed mass loss of the NKGG has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in 2020.The ELA has shifted upwards by 83.0±22 m during the period.Glacier morphological and topographic factors showed a strong influence on glacier recession.Furthermore,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger glaciers.The debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKGG during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin.展开更多
In the hydrological year 2022/2023,the glaciers in the Qilian Mountains experienced unprecedented mass loss.The glacier-wide mass balance was-1,188 mm w.e.,in contrast to-350 mm of average mass balance since 1990 over...In the hydrological year 2022/2023,the glaciers in the Qilian Mountains experienced unprecedented mass loss.The glacier-wide mass balance was-1,188 mm w.e.,in contrast to-350 mm of average mass balance since 1990 over the Bailanghe Glacier No.12 in the middle of Qilian Mountains.The temperature during 2022–2023 reached the highest value ever recorded,second only to 2022,while at the same time the precipitation amount was less compared to other year since 2000,which together led to the strongest glacier mass loss during 2022–2023.The atmospheric circulation analysis shows that the high temperature in the Qilian Mountains in 2023 was jointly caused by the Arctic air mass and East Asian monsoon.展开更多
Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years...Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years 1993,2000,2010,and 2019 using Landsat Thematic Mapper(TM),Enhanced Thematic Mapper(ETM),and Operational Land Imager(OLI)datasets.A total of 251 glaciers,each having an area above 0.5 km^(2),were identified,which include 216 clean-ice and 35 debris-covered glaciers.Area changes are estimated for three periods:1993-2000,2000-2010,and 2010-2019.The total glacierized area was 996±62 km^(2) in 1993,which decreased to 973±70 km^(2) in 2019.The mean rate of glacier area loss was higher in the recent decade(2010-2019),at 0.036 km^(2),compared to previous decades(0.029 km^(2) in 2000-2010 and 0.025 km^(2) in 1993-2000).Supraglacial debris cover changes are also mapped over the period of 1993 and 2019.It is found that the supraglacial debris cover increased by 14.12±2.54 km^(2)(15.2%)during 1993-2019.Extensive field surveys on Chhota Shigri,Panchi II,Patsio,Hamtah,Mulkila,and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite datasets.Controls of various morphological parameters on retreat were also analyzed.It is observed that small,clean ice,south oriented glaciers,and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin.展开更多
Investigating the characteristics and transformation of water-soluble carbonaceous matter in the cryosphere regions is important for understanding biogeochemical process in the earth system.Water-soluble carbonaceous ...Investigating the characteristics and transformation of water-soluble carbonaceous matter in the cryosphere regions is important for understanding biogeochemical process in the earth system.Water-soluble carbonaceous matter is a heterogeneous mixture of organic compounds that is soluble in aquatic environments.Despite its importance,we still lack systematic understanding for dissolved organic carbon(DOC)in several aspects including exact chemical composition and physical interactions with microorganisms,glacier meltwater.This review presents the chemical composition and physical properties of glacier DOC deposited through anthropogenic emission,terrestrial,and biogenic sources.We present the molecular composition of DOC and its effect over snow albedo and associated radiative forcings.Results indicate that DOC in snow/ice is made up of aromatic protein-like species,fulvic acid-like materials,and humic acid-like materials.Light-absorbing impurities in surface snow and glacier ice cause considerable albedo reduction and the associated radiative forcing is definitely positive.Water-soluble carbonaceous matter dominated the carbon transport in the high-altitude glacial area.Owing to prevailing global warming and projected increase in carbon emission,the glacial DOC is expected to release,which will have strong underlying impacts on cryosphere ecosystem.The results of this work have profound implications for better understanding the carbon cycle in high altitude cryosphere regions.A new compilation of globally distributed work is required,including large-scale measurements of glacial DOC over high-altitude cryosphere regions,to overcome and address the scientific challenges to constrain climate impacts of light-absorbing impurities related processes in Earth system and climate models.展开更多
In field trials on Austrian glaciers,nonwovens made of ce u osic LENZING^(TM) fibers are being used to cover glacier mass.They are showing promising results and offer a sustainable solution for glacier protection.Nonw...In field trials on Austrian glaciers,nonwovens made of ce u osic LENZING^(TM) fibers are being used to cover glacier mass.They are showing promising results and offer a sustainable solution for glacier protection.Nonwovens containing fossilbased synthetic fibers might cause negative environmental consequences such as microplastics on glaciers.Geotextiles with ce u osic LENZINGTMfibers won the prestigious Swiss BIO TOP,an award for wood and material innovations.Geotextiles are already widely used to protect snow and ice on glaciers frommelting.展开更多
The highest volcano in Mexico,at the same time the third largest mountain in North America(Citlaltépetl,5610 m a.s.l.),is home to the largest glacier in the country.Because of the extinction of the Popocatép...The highest volcano in Mexico,at the same time the third largest mountain in North America(Citlaltépetl,5610 m a.s.l.),is home to the largest glacier in the country.Because of the extinction of the Popocatépetl glacier(5500 m a.s.l.)caused by eruptive activity,and the almost disappearance of the Iztaccíhuatl glaciers(5220 m a.s.l.)due to the lower elevation of the mountain,the Glaciar Norte of Citlatépetl has been the only glacier that has shown a certain degree of stability as a response to the altitude in which it is located.However,as occurs in almost all glaciers on the planet,the retreat of its glacier terminus has been continuous.Furthermore,during the last years the thickness of its upper part began to decrease rapidly until its bedrock was exposed for the first time in 2019.Due to its ecosystem importance and because it is the main glacier in Mexico,as well as the only one in the world located at latitude 19°N,in this work its current dimensions are updated,as well as the local climatology that governs the current state of the glacier is pointed out.The study was based on the analysis of high-resolution Sentinel-2 optical images,as well as through Sentinel-1 SAR images,with the support of climatological information from the study area.Therefore,the outcropping of the bedrock in the accumulation zone and the consequent horizontal retreat of the upper part of the glacier are documented;at the same time,the decrease in the thickness of the ice along it is noted.The rocky outcrop in the accumulation zone suggests that the flow dynamics of the ice towards the ablation zone will be considerably less,accelerating the retreat of the glacier terminus.Finally,the ascent of the glacial front to 5102 m a.s.l.and the modelled altitude of the equilibrium line to 5276 m a.s.l.are reported as a warning signal in terms of snow catchment and mass balance;likewise,the decrease of 23%of its surface is also indicated regarding the surface reduction monitoring that has been done until 2017.These findings may indicate that the future of this glacier is related to its possible extinction sooner than previously thought,with severe environmental consequences,especially in terms of the provision of drinking water for thousands of inhabitants of the slopes of the volcano.This research is expected to help reflect on the impacts of current climate variability and at the same time serve as a reference for the tropical glaciers on the planet.展开更多
Glacier response patterns at the catchment scale are highly heterogeneous and defined by a complex interplay of various dynamics and surface factors.Previous studies have explained heterogeneous responses in qualitati...Glacier response patterns at the catchment scale are highly heterogeneous and defined by a complex interplay of various dynamics and surface factors.Previous studies have explained heterogeneous responses in qualitative ways but quantitative assessment is lacking yet where an intrazone homogeneous climate assumption can be valid.Hence,in the current study,the reason for heterogeneous mass balance has been explained in quantitative methods using a multiple linear regression model in the Sikkim Himalayan region.At first,the topographical parameters are selected from previously published studies,then the most significant topographical and geomorphological parameters are selected with backward stepwise subset selection methods.Finally,the contributions of selected parameters are calculated by least square methods.The results show that,the magnitude of mass balance lies between-0.003±0.24 to-1.029±0.24 m.w.e.a^(-1) between 2000 and 2020 in the Sikkim Himalaya region.Also,the study shows that,out of the terminus type of the glacier,glacier area,debris cover,ice-mixed debris,slope,aspect,mean elevation,and snout elevation of the glaciers,only the terminus type and mean elevation of the glacier are significantly altering the glacier mass balance in the Sikkim Himalayan region.Mathematically,the mass loss is approximately 0.40 m.w.e.a^(-1) higher in the lake-terminating glaciers compared to the land-terminating glaciers in the same elevation zone.On the other hand,a thousand meters mean elevation drop is associated with 0.179 m.w.e.a-1of mass loss despite the terminus type of the glaciers.In the current study,the model using the terminus type of the glaciers and the mean elevation of the glaciers explains 76% of fluctuation of mass balance in the Sikkim Himalayan region.展开更多
The paper discussed the influence of the forms of sediment accumulation on the surface of glaciers on their chemical and physicochemical properties.The materials sampled from the surface of five glaciers of the Svalba...The paper discussed the influence of the forms of sediment accumulation on the surface of glaciers on their chemical and physicochemical properties.The materials sampled from the surface of five glaciers of the Svalbard Archipelago was analyzed.We studied such forms of sediment accumulation as dirt cones-the ice core covered with sediments and cryoconite holes-hollows on the glacier surface containing cryoconite material.Parameters such as total organic carbon content,microbiological activity,pH,the content of mobile forms of potassium and phosphorus,and concentrations of heavy and trace metals were studied.Also,mesomorphological studies were carried out and the polydisperse composition of the sediments was determined.According to the results of this work,it was found that the content of organic carbon in the material selected from dirt cones and cryoconite holes can be up to 2.5%,but the content of clay particles in it is mainly at the 10–15%level.Potassium concentrations are up to 250 mg/kg,and phosphorus is up to 800 mg/kg.The content of metals is typical or lower than in the previously published data.The main influence on the chemical composition of materials has a geographical factor of the sampling site,rather than the form of material accumulation.展开更多
Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this stud...Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this study,a distributed multi-sensor measurement system for glacier deformation was established by integrating piezoelectric sensing,coded sensing,attitude sensing technology and wireless communication technology.The traditional Modbus protocol was optimized to solve the problem of data identification confusion of different acquisition nodes.Through indoor wireless transmission,adaptive performance analysis,error measurement experiment and landslide simulation experiment,the performance of the measurement system was analyzed and evaluated.Using unmanned aerial vehicle technology,the reliability and effectiveness of the measurement system were verified on the site of Galongla glacier in southeastern Tibet,China.The results show that the mean absolute percentage errors were only 1.13%and 2.09%for the displacement and temperature,respectively.The distributed glacier deformation real-time measurement system provides a new means for the assessment of the development process of glacier disasters and disaster prevention and mitigation.展开更多
Velocity is an important component of glacier dynamics and directly reflects the response of glaciers to climate change.As a result,an accurate determination of seasonal variation in glacier velocity is very important...Velocity is an important component of glacier dynamics and directly reflects the response of glaciers to climate change.As a result,an accurate determination of seasonal variation in glacier velocity is very important in understanding the annual variation in glacier dynamics.However,few studies of glacier velocity in the High Mountain Asia(HMA)region were done.Along these lines,in this work,based on Sentinel-1 glacier velocity data,the distribution of glacier velocity in the HMA region was plotted and their seasonal variations during 2015-2020 were systematically analysed.The average glacier velocity in the HMA region was 0.053 m/d,and was positively correlated with the glacier area and slope.Glaciers in the Karakoram Mountains had the fastest average flow velocity(0.060 m/d),where the glaciers exhibited the largest average area and average slope.Moreover,glaciers in the GangdisêMountains had the slowest velocity(0.022 m/d)and the smallest average glacier area.The glacier flows were the fastest in spring(0.058 m/d),followed by summer(0.050 m/d),autumn(0.041 m/d),and winter(0.040 m/d).In addition,the glacier flows were the maximum in May,being 1.4 times of the annual average velocity.In some areas,such as the Qilian,Altun,Tibetan Interior,Eastern Kunlun,and Western Kunlun mountains,the peak glacier velocities appeared in June and July.The glacier velocity in the HMA region decreased in midsummer and reached the minimum in December when it was 75%of the annual average.These results highlight the role of meltwater in the seasonal variation in glacier flows in late spring and early summer.The seasonal velocity variation of lake-terminating glaciers was similar to that of land-terminating ones,but the former flowed faster.The velocity difference close to the mass balance line between the lake-and land-terminating glaciers was obviously greater in spring than in other seasons.In summer,the difference between the lake-and land-terminating glaciers at a normalized distance of 0.05-0.40 from the terminus was significantly greater than those of other seasons.The velocity difference between the lake-and land-terminating glaciers is closely related to the variable of ice thickness,and also to the frictional force of the terminal base reduced by proglacial lakes.Thus,it can be concluded that in addition to the variation of the glacier thickness and viscosity,the variation of glacier water input also plays a key role in the seasonal variation of glacier velocity.展开更多
Solid precipitation is not only the main supply for glacier mass,but also exerts an important influence on surface albedo and intensifies glacier melting.However,precipitation type observation is very scarce in the hi...Solid precipitation is not only the main supply for glacier mass,but also exerts an important influence on surface albedo and intensifies glacier melting.However,precipitation type observation is very scarce in the high alpine glaciers,which limits the precise simulation of glacier mass balance.This study assessed three discrimination methods of precipitation types including Ding method,Dai method and Froidurot method based on surface albedo observation data on the Laohugou Glacier No.12(LHG Glacier)in western Qilian Mountains.The results showed that Ding method had a best applicability on the LHG Glacier,the other two need to calibrate parameters when they are used in the high elevation glacier region.Then we fitted the relationship between snowfall probability and fresh snow albedo,and put forward a revised formula to simulate fresh snow albedo based on Ding method,which is expected to reduce the uncertainty in glacier mass and energy balance model.Finally,we found a best air temperature threshold of 4℃for discriminating monthly precipitation types.In order to accurately simulate the glacier melt,it is necessary to obtain the threshold temperature appropriately in different glacier region with different elevation and humidity.展开更多
Glacier shrinkage is a globally occurring phenomena.High-resolution change detection based on frequent mapping and monitoring of high-altitude glaciers is necessary to precisely evaluate future water availability and ...Glacier shrinkage is a globally occurring phenomena.High-resolution change detection based on frequent mapping and monitoring of high-altitude glaciers is necessary to precisely evaluate future water availability and to understand glacier evolution under different climatic scenarios in the Hindukush-Karakoram-Himalayan(HKH)region.This also holds true for the Bhaga basin of the western Himalaya.This study investigates glacier and glacier lake changes in the Bhaga basin,over the last five decades based on satellite imagery including Corona KH4(1971),Landsat 7 Enhanced Thematic Mapper Plus(ETM+;2000),Linear Imaging Self-Scanning Sensor(LISS Ⅳ;2013),and Sentinel 2(2020).Regional temperature and precipitation trends were evaluated from gridded climatic datasets(1900–2020).In the Bhaga basin 306 glaciers(>0.2 km^(2))were mapped with a total area of 360.3±4.0 km^(2),of which 55.7±0.6 km^(2)was covered with debris in 2013.The total glacier covered area decreased by∼8.2±1.5%(0.16±0.03%yr-1)during the entire observation period 1971–2020,with noticeable heterogeneity between tributary watersheds.In the past two decades(2000–2020),the deglaciation rate has increased significantly(0.25%yr-1)compared to the previous decades(1971–2000;0.12%yr-1).Glacier lake area increased by 0.6±0.1 km^(2)(0.012 km^(2)yr-1)between 1971 and 2020.The NCEP/NCAR climatic data reveals an increase of 0.63℃in temperature and a decrease of 6.39 mm in precipitation for the period 1948–2018.In comparison,APHRODITE data shows an increasing trend in temperature of 1.14℃between 1961 and 2015 and decreasing trend in precipitation of 31 mm between 1951 and 2007.Both NCEP/NCAR and APHRODITE data reveal significant temperature increase and precipitation decrease since the 1990s,which have probably augmented ice loss in the Bhaga basin during the early 21st century.展开更多
Theδ18O of ice core enclosed gaseous oxygen(δ18Obub)has been widely used for climate reconstruction in polar regions.Yet,less is known about its climatic implication in the mountainous glaciers as the lack of contin...Theδ18O of ice core enclosed gaseous oxygen(δ18Obub)has been widely used for climate reconstruction in polar regions.Yet,less is known about its climatic implication in the mountainous glaciers as the lack of continuous record.Here,we present a long-term,continuousδ18Obub record from the Tanggula glacier in the central Tibetan Plateau(TP).Based on comparisons of its variation with regional climate and glacier changes,we found that there was a good correlation between the variation of theδ18Obub in this alpine ice core and the accumulation and melting of this glacier.The more developed the firn layer on glacier surface,the more positive theδ18Obub.Conversely,the more intense the glacier melting,the more negative theδ18Obub.Combined with the chronology of ice core enclosed gases,the glacier variations since the late Holocene in the central TP were reconstructed.The result showed that there were four accumulation and three deficit periods of glaciers in this region.The strongest glacier accumulation period was 1610-300 B.C.,which corresponds to the Neoglaciation.The most significant melting period was the last 100 years,which corresponds to the recent global warming.The Medieval Warm Period was relatively significant in the central TP.However,during the Little Ice Age,there was no significant glacier accumulation in the central TP,and even short deficit events occurred.Comparisons of the late Holocene glacier variation in the central TP with glacier and climate variations in the TP and the Northern Hemisphere showed that it was closely related to the North Atlantic Oscillation.展开更多
The evolution of mountainous topography is the result of the interactions of climate,topography,and erosion.Glaciers are one of the most active erosional forces sculpting mountainous regions.However,our ability to und...The evolution of mountainous topography is the result of the interactions of climate,topography,and erosion.Glaciers are one of the most active erosional forces sculpting mountainous regions.However,our ability to understand this erosional force is limited by the controversy regarding the major factors controlling glacial erosion.We selected the Nianbaoyeze Shan,which is occupied by subcontinental glaciers(likely cold-based or polythermal glaciers)in the northeastern Tibetan Plateau,to study how erosion by alpine glaciers sculpts the landscape.We first applied a power law model(y=axb)fit to the cross-profiles of glacial valleys and analyzed the controlling factor of glacial erosion;we then identified the morphometric characteristics of the cirques to analyze the influencing factors,and investigated the development patterns of glacial valleys and cirques.Finally,we used hypsometry and the slopealtitude curves and reconstructed the palaeo-glacier surfaces and palaeo-Equilibrium Line Altitudes(ELAs)to determine if the glacial buzzsaw effect had impacted this glaciated region with subcontinental glaciers.Our findings show that ice flux is the main factor controlling glacial erosion.In this region,decreasing temperatures promote an increase in glacier mean size(i.e.,ice flux),which enhances the rate of glacial erosion.Cirque morphology is mainly influenced by aspect and the ELA.The development patterns of glacial valleys and cirques were dominated by a widening process.The ELAs of Marine Isotope Stage(MIS)-3 derived from the cirque floor altitudes or the Accumulation Area Ratio(AAR)and Area-Altitude Balance Ratio(AABR)coincide with the hypsometric maximum and the reduction in slopealtitude curves,which indicates that glacial buzzsaw has impacted this region.Furthermore,the glacial buzzsaw effect has profoundly influenced the mountain heights and topographic evolution in this subcontinental glaciated region.展开更多
The current article is an opinion on the sensitivity of high mountain regions which are the most fragile,sensitive and vulnerable to ongoing climate change.Its impacts are especially severe on the high mountain commun...The current article is an opinion on the sensitivity of high mountain regions which are the most fragile,sensitive and vulnerable to ongoing climate change.Its impacts are especially severe on the high mountain communities owing to their weak socio-economic profile,limited livelihood resources and agricultural land.The melting of glaciers and changes in the snow cover under the climate change scenario is leading to the scarcity of freshwater supplies,affecting both local and downstream communities.Changes in the precipitation patterns have been suggested to cause droughts,impact restricted agriculture,and limit the availability of water for domestic use.Additionally,the high mountain areas contain distinct flora and fauna,and climate change is not just altering them,but also has resulted in biodiversity loss as species are unable to adapt to the changing climate.Because of its higher altitudes and semi-arid to arid climate,the consequences of climate change are more evident in the higher Himalayas.Climate change is affecting the availability of key resources,such as freshwater and agriculture and pasture lands,resulting in food and water insecurity and their reliance on imports from other regions.As a result,high mountain communities in the Himalayas are progressively shifting to higher glacier valleys in search of suitable cultivable land with adequate irrigation.People are engaging in agro-pastoral activities around thermokarst lakes(Oasis)atop rock glaciers as part of this endeavour.Such actions underscore the crucial role of rock glaciers in dealing with and adjusting to the consequences of climate change.Despite its relevance,rock glacier research in the Himalayan region is still in its infancy.The purpose of this work is to emphasise the significance of these major climate-resilient water resources,as well as the methodology that must be adopted for their systematic and compressive investigations.展开更多
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences under Grant No. KZCX2-YW-GJ04National Nature Science Foundation of China (NSFC) under Grant Nos. 41130641 and 41271078
文摘By using a degree-day based distributed hydrological model, regimes of glacial runoff from the Koxkar glacier during 2007-2011 are simulated, and variations and characteristics of major hydrological components are discussed. The results show that the meltwater runoff contributes 67.4%, of the proglacial discharge, out of which snowmelt, clean ice melting, buried-ice ablation and ice-cliff backwasting account for 22.4%, 21.9%, 17.9% and 5.3% of the total melt runoff, respectively. Rainfall runoff is significant in mid-latitude glacierized mountain areas like Tianshan and Karakorum. In the Koxkar glacier catchment, about 11.5% of stream water is initiated from liquid precipitation. Spatial distributions for each glacial runoff component reveal the importance of climatic gradients, local topography and morphology on glacial runoff generation, and temporal variations of these components is closely related to the annual cycle of catchment meteorology and glacier storage. Four stages are recognized in the seasonal variations of glacier storage, reflecting changes in meltwater yields, meteorological conditions and drainage systems in the annual hydrological cycle.
文摘Glaciers in the Shaksgam valley provide important fresh water resources to neighbourhood livelihood. Repeated creation of the glacier inventories is important to assess glacier–climate interactions and to predict future runoff from glacierized catchments. For this study, we applied a multi-criteria technique to map the glaciers of the Shaksgam valley of China, using Landsat Thematic Mapper(Landsat TM)(2009) and Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model version two(ASTER GDEM V2) data. The geomorphometric parameters slope, plan, and profile curvature were generated from ASTER GDEM. Then they were organized in similar surface groups using cluster analysis. For accurate mapping of supraglacial debris area, clustering results were combined with a thermal mask generated from the Landsat TM thermal band. The debris-free glaciers were identified using the band ratio(TM band 4/TM band 5) technique. Final vector maps of the glaciers were created using overlay tools in a geographic information system(GIS).Accuracy of the generated glacier outlines was assessed through comparison with glacier outlines based on the Second Chinese Glacier Inventory(SCGI) data and glacier outlines created from high-resolution Google Earth? images of 2009. Glacier areas derived using the proposed approach were 3% less than in the reference datasets. Furthermore, final glacier maps show satisfactory mapping results, but identification of the debris-cover glacier terminus(covered by thick debris layer) is still problematic. Therefore, manual editing was necessary to improve the final glacier maps.
基金as part of the Department of Science and Technology (DST), Government of India sponsored research projects titled “Centre of Excellence for Glaciological Research in Western Himalaya”the financial assistance received from the Department under the projects to conduct the research。
文摘Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun Group of Glaciers(NKGG),were investigated using Landsat satellite data during 2000-2020.Changes in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field observations.The study revealed that the NKGG glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation period.Using the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and 2012.The observed mass loss of the NKGG has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in 2020.The ELA has shifted upwards by 83.0±22 m during the period.Glacier morphological and topographic factors showed a strong influence on glacier recession.Furthermore,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger glaciers.The debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKGG during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin.
基金supported by the Science Fund for Creative Research Groups of Gansu Province (Grant No.23JRRA567)the National Natural Science Foundation of China (42101139,42071018)+1 种基金Meteorological Administration Climate Change Special Program (CMA-CCSP:QBZ202308)CAS"Light of West China"Program。
文摘In the hydrological year 2022/2023,the glaciers in the Qilian Mountains experienced unprecedented mass loss.The glacier-wide mass balance was-1,188 mm w.e.,in contrast to-350 mm of average mass balance since 1990 over the Bailanghe Glacier No.12 in the middle of Qilian Mountains.The temperature during 2022–2023 reached the highest value ever recorded,second only to 2022,while at the same time the precipitation amount was less compared to other year since 2000,which together led to the strongest glacier mass loss during 2022–2023.The atmospheric circulation analysis shows that the high temperature in the Qilian Mountains in 2023 was jointly caused by the Arctic air mass and East Asian monsoon.
基金the Space Application Center, Ahmedabad (ISRO) for providing field support under “Integrated studies of Himalayan Cryosphere” programthe Glaciology Group, Jawaharlal Nehru University for providing necessary support for this research+1 种基金the grants from SERB (CRG/2020/004877) and MOES/16/19/2017-RDEAS projectsthe support from ISRO/RES/4/690/21-22 project
文摘Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years 1993,2000,2010,and 2019 using Landsat Thematic Mapper(TM),Enhanced Thematic Mapper(ETM),and Operational Land Imager(OLI)datasets.A total of 251 glaciers,each having an area above 0.5 km^(2),were identified,which include 216 clean-ice and 35 debris-covered glaciers.Area changes are estimated for three periods:1993-2000,2000-2010,and 2010-2019.The total glacierized area was 996±62 km^(2) in 1993,which decreased to 973±70 km^(2) in 2019.The mean rate of glacier area loss was higher in the recent decade(2010-2019),at 0.036 km^(2),compared to previous decades(0.029 km^(2) in 2000-2010 and 0.025 km^(2) in 1993-2000).Supraglacial debris cover changes are also mapped over the period of 1993 and 2019.It is found that the supraglacial debris cover increased by 14.12±2.54 km^(2)(15.2%)during 1993-2019.Extensive field surveys on Chhota Shigri,Panchi II,Patsio,Hamtah,Mulkila,and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite datasets.Controls of various morphological parameters on retreat were also analyzed.It is observed that small,clean ice,south oriented glaciers,and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin.
基金supported by the second Tibetan Plateau Scientific Expedition and Research Program(STEP)(2019QZKK0605)the National Natural Science Foundation of China(41971080)the support of Youth Innovation Promotion Association CAS(2021429)。
文摘Investigating the characteristics and transformation of water-soluble carbonaceous matter in the cryosphere regions is important for understanding biogeochemical process in the earth system.Water-soluble carbonaceous matter is a heterogeneous mixture of organic compounds that is soluble in aquatic environments.Despite its importance,we still lack systematic understanding for dissolved organic carbon(DOC)in several aspects including exact chemical composition and physical interactions with microorganisms,glacier meltwater.This review presents the chemical composition and physical properties of glacier DOC deposited through anthropogenic emission,terrestrial,and biogenic sources.We present the molecular composition of DOC and its effect over snow albedo and associated radiative forcings.Results indicate that DOC in snow/ice is made up of aromatic protein-like species,fulvic acid-like materials,and humic acid-like materials.Light-absorbing impurities in surface snow and glacier ice cause considerable albedo reduction and the associated radiative forcing is definitely positive.Water-soluble carbonaceous matter dominated the carbon transport in the high-altitude glacial area.Owing to prevailing global warming and projected increase in carbon emission,the glacial DOC is expected to release,which will have strong underlying impacts on cryosphere ecosystem.The results of this work have profound implications for better understanding the carbon cycle in high altitude cryosphere regions.A new compilation of globally distributed work is required,including large-scale measurements of glacial DOC over high-altitude cryosphere regions,to overcome and address the scientific challenges to constrain climate impacts of light-absorbing impurities related processes in Earth system and climate models.
文摘In field trials on Austrian glaciers,nonwovens made of ce u osic LENZING^(TM) fibers are being used to cover glacier mass.They are showing promising results and offer a sustainable solution for glacier protection.Nonwovens containing fossilbased synthetic fibers might cause negative environmental consequences such as microplastics on glaciers.Geotextiles with ce u osic LENZINGTMfibers won the prestigious Swiss BIO TOP,an award for wood and material innovations.Geotextiles are already widely used to protect snow and ice on glaciers frommelting.
文摘The highest volcano in Mexico,at the same time the third largest mountain in North America(Citlaltépetl,5610 m a.s.l.),is home to the largest glacier in the country.Because of the extinction of the Popocatépetl glacier(5500 m a.s.l.)caused by eruptive activity,and the almost disappearance of the Iztaccíhuatl glaciers(5220 m a.s.l.)due to the lower elevation of the mountain,the Glaciar Norte of Citlatépetl has been the only glacier that has shown a certain degree of stability as a response to the altitude in which it is located.However,as occurs in almost all glaciers on the planet,the retreat of its glacier terminus has been continuous.Furthermore,during the last years the thickness of its upper part began to decrease rapidly until its bedrock was exposed for the first time in 2019.Due to its ecosystem importance and because it is the main glacier in Mexico,as well as the only one in the world located at latitude 19°N,in this work its current dimensions are updated,as well as the local climatology that governs the current state of the glacier is pointed out.The study was based on the analysis of high-resolution Sentinel-2 optical images,as well as through Sentinel-1 SAR images,with the support of climatological information from the study area.Therefore,the outcropping of the bedrock in the accumulation zone and the consequent horizontal retreat of the upper part of the glacier are documented;at the same time,the decrease in the thickness of the ice along it is noted.The rocky outcrop in the accumulation zone suggests that the flow dynamics of the ice towards the ablation zone will be considerably less,accelerating the retreat of the glacier terminus.Finally,the ascent of the glacial front to 5102 m a.s.l.and the modelled altitude of the equilibrium line to 5276 m a.s.l.are reported as a warning signal in terms of snow catchment and mass balance;likewise,the decrease of 23%of its surface is also indicated regarding the surface reduction monitoring that has been done until 2017.These findings may indicate that the future of this glacier is related to its possible extinction sooner than previously thought,with severe environmental consequences,especially in terms of the provision of drinking water for thousands of inhabitants of the slopes of the volcano.This research is expected to help reflect on the impacts of current climate variability and at the same time serve as a reference for the tropical glaciers on the planet.
文摘Glacier response patterns at the catchment scale are highly heterogeneous and defined by a complex interplay of various dynamics and surface factors.Previous studies have explained heterogeneous responses in qualitative ways but quantitative assessment is lacking yet where an intrazone homogeneous climate assumption can be valid.Hence,in the current study,the reason for heterogeneous mass balance has been explained in quantitative methods using a multiple linear regression model in the Sikkim Himalayan region.At first,the topographical parameters are selected from previously published studies,then the most significant topographical and geomorphological parameters are selected with backward stepwise subset selection methods.Finally,the contributions of selected parameters are calculated by least square methods.The results show that,the magnitude of mass balance lies between-0.003±0.24 to-1.029±0.24 m.w.e.a^(-1) between 2000 and 2020 in the Sikkim Himalaya region.Also,the study shows that,out of the terminus type of the glacier,glacier area,debris cover,ice-mixed debris,slope,aspect,mean elevation,and snout elevation of the glaciers,only the terminus type and mean elevation of the glacier are significantly altering the glacier mass balance in the Sikkim Himalayan region.Mathematically,the mass loss is approximately 0.40 m.w.e.a^(-1) higher in the lake-terminating glaciers compared to the land-terminating glaciers in the same elevation zone.On the other hand,a thousand meters mean elevation drop is associated with 0.179 m.w.e.a-1of mass loss despite the terminus type of the glaciers.In the current study,the model using the terminus type of the glaciers and the mean elevation of the glaciers explains 76% of fluctuation of mass balance in the Sikkim Himalayan region.
基金supported by Russian Foundation for Basic Research(project No 19-05-50107)"The role of microparticles of organic carbon in degradation of ice cover of polar regions of the Earth and in the process of soil-like bodies formation".
文摘The paper discussed the influence of the forms of sediment accumulation on the surface of glaciers on their chemical and physicochemical properties.The materials sampled from the surface of five glaciers of the Svalbard Archipelago was analyzed.We studied such forms of sediment accumulation as dirt cones-the ice core covered with sediments and cryoconite holes-hollows on the glacier surface containing cryoconite material.Parameters such as total organic carbon content,microbiological activity,pH,the content of mobile forms of potassium and phosphorus,and concentrations of heavy and trace metals were studied.Also,mesomorphological studies were carried out and the polydisperse composition of the sediments was determined.According to the results of this work,it was found that the content of organic carbon in the material selected from dirt cones and cryoconite holes can be up to 2.5%,but the content of clay particles in it is mainly at the 10–15%level.Potassium concentrations are up to 250 mg/kg,and phosphorus is up to 800 mg/kg.The content of metals is typical or lower than in the previously published data.The main influence on the chemical composition of materials has a geographical factor of the sampling site,rather than the form of material accumulation.
基金funded by National Key R&D Program of China((Nos.2022YFC3003403 and 2018YFC1505203)Key Research and Development Program of Tibet Autonomous Region(XZ202301ZY0039G)+1 种基金Natural Science Foundation of Hebei Province(No.F2021201031)Geological Survey Project of China Geological Survey(No.DD20221747)。
文摘Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this study,a distributed multi-sensor measurement system for glacier deformation was established by integrating piezoelectric sensing,coded sensing,attitude sensing technology and wireless communication technology.The traditional Modbus protocol was optimized to solve the problem of data identification confusion of different acquisition nodes.Through indoor wireless transmission,adaptive performance analysis,error measurement experiment and landslide simulation experiment,the performance of the measurement system was analyzed and evaluated.Using unmanned aerial vehicle technology,the reliability and effectiveness of the measurement system were verified on the site of Galongla glacier in southeastern Tibet,China.The results show that the mean absolute percentage errors were only 1.13%and 2.09%for the displacement and temperature,respectively.The distributed glacier deformation real-time measurement system provides a new means for the assessment of the development process of glacier disasters and disaster prevention and mitigation.
基金supported by the Major Project on Natural Science Foundation of Universities in Anhui Province (2022AH040111)the National Natural Science Foundation of China (42071085,41701087)。
文摘Velocity is an important component of glacier dynamics and directly reflects the response of glaciers to climate change.As a result,an accurate determination of seasonal variation in glacier velocity is very important in understanding the annual variation in glacier dynamics.However,few studies of glacier velocity in the High Mountain Asia(HMA)region were done.Along these lines,in this work,based on Sentinel-1 glacier velocity data,the distribution of glacier velocity in the HMA region was plotted and their seasonal variations during 2015-2020 were systematically analysed.The average glacier velocity in the HMA region was 0.053 m/d,and was positively correlated with the glacier area and slope.Glaciers in the Karakoram Mountains had the fastest average flow velocity(0.060 m/d),where the glaciers exhibited the largest average area and average slope.Moreover,glaciers in the GangdisêMountains had the slowest velocity(0.022 m/d)and the smallest average glacier area.The glacier flows were the fastest in spring(0.058 m/d),followed by summer(0.050 m/d),autumn(0.041 m/d),and winter(0.040 m/d).In addition,the glacier flows were the maximum in May,being 1.4 times of the annual average velocity.In some areas,such as the Qilian,Altun,Tibetan Interior,Eastern Kunlun,and Western Kunlun mountains,the peak glacier velocities appeared in June and July.The glacier velocity in the HMA region decreased in midsummer and reached the minimum in December when it was 75%of the annual average.These results highlight the role of meltwater in the seasonal variation in glacier flows in late spring and early summer.The seasonal velocity variation of lake-terminating glaciers was similar to that of land-terminating ones,but the former flowed faster.The velocity difference close to the mass balance line between the lake-and land-terminating glaciers was obviously greater in spring than in other seasons.In summer,the difference between the lake-and land-terminating glaciers at a normalized distance of 0.05-0.40 from the terminus was significantly greater than those of other seasons.The velocity difference between the lake-and land-terminating glaciers is closely related to the variable of ice thickness,and also to the frictional force of the terminal base reduced by proglacial lakes.Thus,it can be concluded that in addition to the variation of the glacier thickness and viscosity,the variation of glacier water input also plays a key role in the seasonal variation of glacier velocity.
基金supported by the National key research and development project(2022YFF0711704)the Science Fund for Creative Research Groups of Gansu Province(Grant No.23JRRA567)+2 种基金China Meteorological Administration Climate Change Special Program(CMA-CCSP:QBZ202308)Innovation and Development Project of China Meteorological Administration(CXFZ2022J039)the Gansu Provincial Science and Technology Program(22ZD6FA005)。
文摘Solid precipitation is not only the main supply for glacier mass,but also exerts an important influence on surface albedo and intensifies glacier melting.However,precipitation type observation is very scarce in the high alpine glaciers,which limits the precise simulation of glacier mass balance.This study assessed three discrimination methods of precipitation types including Ding method,Dai method and Froidurot method based on surface albedo observation data on the Laohugou Glacier No.12(LHG Glacier)in western Qilian Mountains.The results showed that Ding method had a best applicability on the LHG Glacier,the other two need to calibrate parameters when they are used in the high elevation glacier region.Then we fitted the relationship between snowfall probability and fresh snow albedo,and put forward a revised formula to simulate fresh snow albedo based on Ding method,which is expected to reduce the uncertainty in glacier mass and energy balance model.Finally,we found a best air temperature threshold of 4℃for discriminating monthly precipitation types.In order to accurately simulate the glacier melt,it is necessary to obtain the threshold temperature appropriately in different glacier region with different elevation and humidity.
基金the University Grant Commission, New Delhi (3090/ (NET–DEC.2014) for financial support during field visitsthe Department of Science and Technology, Govt of India, for sponsoring the project “Himalayan Cryosphere: Science and Society”
文摘Glacier shrinkage is a globally occurring phenomena.High-resolution change detection based on frequent mapping and monitoring of high-altitude glaciers is necessary to precisely evaluate future water availability and to understand glacier evolution under different climatic scenarios in the Hindukush-Karakoram-Himalayan(HKH)region.This also holds true for the Bhaga basin of the western Himalaya.This study investigates glacier and glacier lake changes in the Bhaga basin,over the last five decades based on satellite imagery including Corona KH4(1971),Landsat 7 Enhanced Thematic Mapper Plus(ETM+;2000),Linear Imaging Self-Scanning Sensor(LISS Ⅳ;2013),and Sentinel 2(2020).Regional temperature and precipitation trends were evaluated from gridded climatic datasets(1900–2020).In the Bhaga basin 306 glaciers(>0.2 km^(2))were mapped with a total area of 360.3±4.0 km^(2),of which 55.7±0.6 km^(2)was covered with debris in 2013.The total glacier covered area decreased by∼8.2±1.5%(0.16±0.03%yr-1)during the entire observation period 1971–2020,with noticeable heterogeneity between tributary watersheds.In the past two decades(2000–2020),the deglaciation rate has increased significantly(0.25%yr-1)compared to the previous decades(1971–2000;0.12%yr-1).Glacier lake area increased by 0.6±0.1 km^(2)(0.012 km^(2)yr-1)between 1971 and 2020.The NCEP/NCAR climatic data reveals an increase of 0.63℃in temperature and a decrease of 6.39 mm in precipitation for the period 1948–2018.In comparison,APHRODITE data shows an increasing trend in temperature of 1.14℃between 1961 and 2015 and decreasing trend in precipitation of 31 mm between 1951 and 2007.Both NCEP/NCAR and APHRODITE data reveal significant temperature increase and precipitation decrease since the 1990s,which have probably augmented ice loss in the Bhaga basin during the early 21st century.
基金supported by the National Natural Science Foundation of China(Grant No.42271312,41201058)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA20070102)+1 种基金the National Key R&D Program of China(Grant No.2018YFB1307504)the Science and Technology Program of Tibet Autonomous Region of China(Grant No.XZ202101ZD0014G).
文摘Theδ18O of ice core enclosed gaseous oxygen(δ18Obub)has been widely used for climate reconstruction in polar regions.Yet,less is known about its climatic implication in the mountainous glaciers as the lack of continuous record.Here,we present a long-term,continuousδ18Obub record from the Tanggula glacier in the central Tibetan Plateau(TP).Based on comparisons of its variation with regional climate and glacier changes,we found that there was a good correlation between the variation of theδ18Obub in this alpine ice core and the accumulation and melting of this glacier.The more developed the firn layer on glacier surface,the more positive theδ18Obub.Conversely,the more intense the glacier melting,the more negative theδ18Obub.Combined with the chronology of ice core enclosed gases,the glacier variations since the late Holocene in the central TP were reconstructed.The result showed that there were four accumulation and three deficit periods of glaciers in this region.The strongest glacier accumulation period was 1610-300 B.C.,which corresponds to the Neoglaciation.The most significant melting period was the last 100 years,which corresponds to the recent global warming.The Medieval Warm Period was relatively significant in the central TP.However,during the Little Ice Age,there was no significant glacier accumulation in the central TP,and even short deficit events occurred.Comparisons of the late Holocene glacier variation in the central TP with glacier and climate variations in the TP and the Northern Hemisphere showed that it was closely related to the North Atlantic Oscillation.
基金funded by the National Natural Science Foundation of China(Grant Nos.41971003)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant Nos.2019QZKK0205)the Science and technology Project of Tibet Autonomous Region(Grant Nos.XZ202101ZY0001G)。
文摘The evolution of mountainous topography is the result of the interactions of climate,topography,and erosion.Glaciers are one of the most active erosional forces sculpting mountainous regions.However,our ability to understand this erosional force is limited by the controversy regarding the major factors controlling glacial erosion.We selected the Nianbaoyeze Shan,which is occupied by subcontinental glaciers(likely cold-based or polythermal glaciers)in the northeastern Tibetan Plateau,to study how erosion by alpine glaciers sculpts the landscape.We first applied a power law model(y=axb)fit to the cross-profiles of glacial valleys and analyzed the controlling factor of glacial erosion;we then identified the morphometric characteristics of the cirques to analyze the influencing factors,and investigated the development patterns of glacial valleys and cirques.Finally,we used hypsometry and the slopealtitude curves and reconstructed the palaeo-glacier surfaces and palaeo-Equilibrium Line Altitudes(ELAs)to determine if the glacial buzzsaw effect had impacted this glaciated region with subcontinental glaciers.Our findings show that ice flux is the main factor controlling glacial erosion.In this region,decreasing temperatures promote an increase in glacier mean size(i.e.,ice flux),which enhances the rate of glacial erosion.Cirque morphology is mainly influenced by aspect and the ELA.The development patterns of glacial valleys and cirques were dominated by a widening process.The ELAs of Marine Isotope Stage(MIS)-3 derived from the cirque floor altitudes or the Accumulation Area Ratio(AAR)and Area-Altitude Balance Ratio(AABR)coincide with the hypsometric maximum and the reduction in slopealtitude curves,which indicates that glacial buzzsaw has impacted this region.Furthermore,the glacial buzzsaw effect has profoundly influenced the mountain heights and topographic evolution in this subcontinental glaciated region.
文摘The current article is an opinion on the sensitivity of high mountain regions which are the most fragile,sensitive and vulnerable to ongoing climate change.Its impacts are especially severe on the high mountain communities owing to their weak socio-economic profile,limited livelihood resources and agricultural land.The melting of glaciers and changes in the snow cover under the climate change scenario is leading to the scarcity of freshwater supplies,affecting both local and downstream communities.Changes in the precipitation patterns have been suggested to cause droughts,impact restricted agriculture,and limit the availability of water for domestic use.Additionally,the high mountain areas contain distinct flora and fauna,and climate change is not just altering them,but also has resulted in biodiversity loss as species are unable to adapt to the changing climate.Because of its higher altitudes and semi-arid to arid climate,the consequences of climate change are more evident in the higher Himalayas.Climate change is affecting the availability of key resources,such as freshwater and agriculture and pasture lands,resulting in food and water insecurity and their reliance on imports from other regions.As a result,high mountain communities in the Himalayas are progressively shifting to higher glacier valleys in search of suitable cultivable land with adequate irrigation.People are engaging in agro-pastoral activities around thermokarst lakes(Oasis)atop rock glaciers as part of this endeavour.Such actions underscore the crucial role of rock glaciers in dealing with and adjusting to the consequences of climate change.Despite its relevance,rock glacier research in the Himalayan region is still in its infancy.The purpose of this work is to emphasise the significance of these major climate-resilient water resources,as well as the methodology that must be adopted for their systematic and compressive investigations.