Temperate glaciers in the southeastern Tibetan Plateau have experienced significant mass loss and retreat in recent decades, yet detailed on-site observations remain limited. Here we present the measured records of surface mass balance, ice velocity and surface ice temperature of Baishui River Glacier No. 1 in Yulong Snow Mountain from 2018 to 2022. Our observations reveal an annual mean mass balance of −1.29±0.16 m w.e., demonstrating a significant seasonal imbalance between reduced accumulation (multi-year average of 0.51±0.07 m w.e.) and enhanced ablation (multi-year average of 1.80±0.26 m w.e.), which provides crucial evidence for explaining the long-term mass loss. The average annual ice velocity, predominantly controlled by monsoon season dynamics which contribute 69

Temperate glaciers in the southeastern Tibetan Plateau are shrinking rapidly in response to ongoing climate change. This study focuses on the Baishui River Glacier No. 1, a typical temperate glacier in the Yulong Snow Mountain. Through field observations over four years, we have obtained records and valuable data on the mass balance, ice flow velocity and emergence velocity. The results show that it has been in a state of negative mass balance in recent 4‐years. The mass loss ranges from 1.17 ± 0.18 to 1.46 ± 0.25 m w.e., with an average annual mass loss of 1.29 ± 0.17 m w.e. The average ice flow velocity is ~29.24 ± 3.51 m yr −1 , with spatial differences related to glacier morphology and mass turnover. These differences can be attributed to the glacier's morphological characteristics (such as width, slope, thickness and crevasse) and the large mass turnover conditions. In its low‐latitude wet climate, BRG1 has a fast emergence velocity of ~4.07 ± 1.03 m yr −1 . The emergent ice flow is insufficient cannot offset melting. Slope change uncertainties hamper calculating surface mass balance from emergence velocity. Our data reveals a significant correlation (r 2 = 0.69) between ice flow velocity and emergence velocity, and a very significant negative one (r 2 = 0.78) between ice flow velocity and mass balance. Faster ice flow transports more ice to lower, warmer areas, accelerating melting. The data presented in this article offers valuable and useful insights into the physical ice flow model of such low‐latitude temperate glaciers.

Aerosol samples were collected during pre-monsoon, monsoon and post-monsoon periods in 2009 in Lijiang, a tourism city located on the southeast Tibetan Plateau, southwest China. To determine the seasonal variation and sources of aerosol species, main elements and water soluble ions were analyzed. The results showed that crustal elements (Si, K, Ca, Ti and Fe) were the main elements with an enrichment whose enrichment factor (EF) value were lower than 10, with the large value (except Ca) occurring during the pre-monsoon period. The EF values of S, Cl, Zn, As, Br, Sb, Pb, and Cu were higher than those of the crustal elements and the large concentration appeared during the monsoon period. Ca2+ and SO42– were the dominant cation and anion, respectively. The greatest value of total ionic concentration was found during the monsoon period, mainly because of the high concentration of SO42– and NH4+. Using the positive matrix factorization model, it was found that the main sources of species were from crustal source, transport from south Asia and eastern China, local vehicle emissions and sea salt. Further results indicated that the pollutants mixed with dust, anthropogenic pollutants and biomass burning emissions can be transported to Lijiang from south Asia and Southeast Asia during the pre-monsoon period. In addition, pollutants rich in SO42– and heavy metal from the Sichuan Basin and eastern Yunnan Province can also be occasionally transported to Lijiang during the monsoon period. The seasonal differences in chemical composition and transportation pathway may have important implications for regional climate change.

After nearly 20 years of development,the Yulong Snow Mountain National Field Observation and Research Station for Cryosphere and Sustainable Development,Chinese Academy of Sciences has built a field comprehensive observation system and data online visualization platform of temperate glacier and environment integrating observation,research,demonstration,and service.Based on the long-term positioning monitoring of temperate glaciers and the environment,and focusing on key scientific issues related to sustainable development in temperate glacier areas,this study deeply analyzes the mechanism of changes in temperate glaciers,reveals the hydrological,microorganisms,and climatic effects of temperate glacier change,evaluates the effectiveness of temperate glacier tourism services and integrated risk of glacial lake outburst disasters,and provides scientific and technological support for regional sustainable development.

Glacier mass balance provides a sensitive barometer of climate-glacier interactions, yet only a few glaciers have been continuously well-documented. Here we evaluated the retreat status of Baishui River Glacier No. 1 (reference glacier of Yulong Snow Mountain) during the 1951-2020 period and explored its response to climate change. In particular, based on 12-years of continuous in-situ measurements, we presented the first comprehensive set of mass balance for the Baishui River Glacier No. 1 from 2008 to 2020. The result shows that the Baishui River Glacier No. 1 suffered sustained shrinkage in terms of both its area (which fell by 36 %) and reserves (with cumulative mass losses over 32.38 +/- 3.62 m w.e.) over the past 70-years. The terminus rose from 4100 m asl in 1982 to 4395 m asl in 2017. The equilibrium line altitude has risen above the glacier's summit since 2010, and the accumulation zone disappeared. Since the 1980s, the acceleration of glacier retreat has become established, and has been further strengthened after 2000, this corresponds to the process of climate warming. In-situ measurements showed that any glacial accumulation during the non-monsoon period (with a multiyear mean of 0.53 +/- 0.08 m w.e.) fell far short of offsetting the ablation driven by both air temperature and liquid precipitation in the monsoon season (with a multiyear mean of 2.08 +/- 0.20 m w.e.), meaning that the glacier could not attain a state of equilibrium, and quickly lost a significant mass (with multiyear mean losses of 1.54 +/- 0.30 m w.e.). Given that, the current atmospheric conditions are unlikely to allow Baishui River Glacier No. 1 to suppress its loss trend.

We seek to use electrically conducting polymers, such as those commonly utilized in polymeric LEDs, as hosts for silicon nanoparticles. The proper design of multilayered devices based on these materials will yield efficient light-emitters in which charge carriers localize and recombine within the nanoparticles. Furthermore, these may combine the flexibility and processability of polymeric LEDs with the reliability of inorganic materials. We have synthesized luminescent silicon nanoparticles and have characterized their photoluminescence (PL) using continuous-wave and time-resolved spectroscopy. These particles have been, incorporated into a variety of transparent solid hosts. The photoluminescence obtained from particle-containing poly(methyl methacrylate) (PMMA) matrices is very similar to that of the particles in solution, both in spectral content and PL decay characteristics. However, when incorporated into a variety of conducting polymers, such as poly(N-vinylcarbazole) (PVK), the nanoparticles do not retain their photoluminescence properties. A variety of chemical species have been reported as effective PL quenchers for porous silicon. We believe that these polymers quench the luminescence through similar mechanisms. Protective passivation of the nanoparticle surface is suggested as a strategy for overcoming this quenching.

Daily precipitation samples were collected at four sites in Mount Yulong and Mount Meili regions of southeastern Tibetan Plateau and analyzed for isotopic composition. Combined with water vapor isotopic composition derived from satellites data (Infrared Atmospheric Sounding Interferometer, Tropospheric Emission Spectrometer, and Greenhouse gases Observing Satellite), the factors controlling the variability in the isotopic composition of precipitation are investigated at the synoptic, intraseasonal, and seasonal time scales. At the seasonal scale, the isotope composition in precipitation is controlled by processes along air mass trajectories affecting the water vapor at the large scale (>200 km), especially upstream deep convection and air mass origin, and by local processes transforming the large-scale water vapor isotopic composition into the precipitation composition, especially rain evaporation and local circulation. At the intraseasonal and synoptic scales, the isotope composition in precipitation is mainly controlled by these local processes. The shorter the time scale of isotopic variations, the smaller the spatial imprint of these variations. The fact that different factors control the isotopic variability at different time scales calls for caution when applying relationships observed at these time scales to interpret isotopic variations at paleoclimatic time scales. While general circulation models successfully capture the isotopic variability and its controlling factors at the seasonal scale, it fails to simulate them at shorter time scales, because it fails to simulate the local processes. Plain Language Summary Water molecules can be light (one oxygen atom and two hydrogen atoms) or heavy (one hydrogen atom is replaced by a deuterium atom). These different molecules are called water isotopes. The isotopic composition of precipitation, when recorded in ice cores, can provide information about past climate. In southeastern TP ice cores, the isotopic records have been interpreted as reflecting past variations in temperature,or as reflecting past variations in monsoon strength. This illustrates that we need to better understand what processes control the isotopic composition of precipitation. We investigate the processes at the seasonal (>1 month), intraseasonal (10-30 days), and synoptic (<10 days) time scales. We use precipitation samples collected in the southeastern TP and satellite retrievals of water vapor isotope. We show that storm activity along air mass trajectories is an important factor controlling isotopic variations at the seasonal scale. But local processes, such as the evaporation of rain drops or local winds, are also important, especially at shorter time scales. The fact that the processes control the isotopic composition of precipitation depend on the time scale calls for caution when applying the factors observed in present-day variability to interpret isotopic ice core records at very long time scales.

Using ground-penetrating radar (GPR), we measured and estimated the ice thickness of the Baishui River Glacier No. 1 of Yulong Snow Mountain. According to the position of the reflected media from the GPR image, combined with the radar waveform amplitude and polarity change information, the ice thickness and the changing medium position at the bottom of this temperate glacier were identified. Water paths were found in the measured ice, including ice caves and crevasses. A debris-rich ice layer was found at the bottom of the glacier, which produces strong abrasion and ploughing action at the bedrock surface. This results in the formation of different detrital layers stagnated at the ice-bedrock interface and numerous crevasses on the bedrock surface. Based on the obtained ice thickness and differential GPS data, combined with Landsat images, the kriging interpolation method was used to obtain grid data. The average ice thickness was 52.48 m and between 4740 and 4890 m above sea level, with a maximum depth of 92.83 m. The bedrock topography map of this area was drawn using digital elevation model from the Shuttle Radar Topography Mission. The central part of the glacier was characterized by small ice basins with distributed ice steps and ice ridges at the upper and lower parts.

Observing the isotopic evolution of snow meltwater helps in understanding the process of snow melting but remains a challenge to acquire in the field. In this study, we monitored the melting of two snowpacks near Baishui Glacier No. 1, a typical temperate glacier on the southeastern Tibetan Plateau. We employed a physically based isotope model (PBIM) to calculate the isotopic composition of meltwater draining from natural snowpacks. The initial condition of the PBIM was revised to account for natural conditions, i.e., the initial delta O-18 stratigraphy of snow layers before melting. Simulations revealed that the initial heterogeneity of delta O-18 in snow layers as well as ice-liquid isotopic exchange were responsible for most variations of delta O-18 in snow meltwater, whereas new snow and wind drift could result in sudden changes of the isotopic composition of the meltwater. The fraction of ice involved in the isotopic exchange (f) was the most sensitive parameter for the model output. The initial delta O-18 in the snowpack is mirrored in meltwater in case of smallfand is smoothed with a large exchange fractionf. The other unknown parameter of the PBIM is the dimensionless rate constant of isotopic exchange, which depends on water percolation and initial snow depth. The successful application of the PBIM in the field might not only be useful for understanding snow melting process but might also provide the possibility of predicting the isotopic composition of snow meltwater and improve the accuracy of hydrograph separation.

It is the basis of isotope technology application to clarify which factors are related to precipitation isotopes in different regions. China has a vast territory, and there is still no comprehensive and systematic understanding of the spatial distribution pattern and influencing factors of precipitation stable isotopes in China. Based on the known Bowen and Wilkinson model, the latitude and altitude of 117 sites in China were used to simulate δ 18 O value of each site and to generate the high precision spatial distribution map of the precipitation oxygen stable isotope over China. According to the spatial distribution of precipitation δ 18 O, the basic effects of isotope variation in different climatic regions were analyzed: latitude effect, elevation effect, temperature effect, precipitation effect, and water vapor source and transportation process. In the eastern monsoon region, the latitude effect of isotope variation is shown, but the difference between the southern region and the northern region is large. The southern region is affected by the water vapor of the subtropical Pacific Ocean and precipitation amount effect to form a high value area of δ 18 O, and the northern region is more susceptible to the temperature effect. In the same latitude area, due to the influence of local recycled water vapor and local evaporation, a high-value area of δ 18 O is formed in the inland basin of the northwestern arid region. In the Qinghai–Tibet Plateau, the isotope values affected by the high terrain are generally low. The change of δ 18 O value reflects the extent to which the south and north areas of the Qinghai–Tibet Plateau are affected by the southwest monsoon and local water vapor.

利用2011年10月1日至2012年9月30日玉龙雪山白水1号冰川海拔4500 m气象观测资料,对位于我国最南、亚欧大陆距赤道最近的海洋型冰川区近地层气象要素基本特征进行了分析,并与同海拔大陆型冰川——祁连山老虎沟12号冰川区近地层气象要素进行了对比.研究表明:海洋型与大陆型冰川区气温逐时变化呈单峰单谷型分布,均表现出升温快降温慢的特点,观测点5 m层气温高于2 m层气温,二者差值日变化呈单峰型,峰值出现在北京时间12:00;受季风气候影响,研究区干季相对湿度小,湿季相对湿度大,年均相对湿度为73.3％,与相对湿度相比,研究区水汽压变化更受控于气温;两冰川区冬半年气压低,夏半年气压高,均表现为典型的"高山型"气压;受冰川"冷效应"影响研究区干季风速大,湿季风速小,因冰川规模较小,研究区冰川风不发达,谷风发育强劲;受季风期云雨影响,白水1号冰川区总辐射在季风前期达到最大值,季风期达到极小值,年均总辐射量低于老虎沟12号冰川同海拔地区.

From July 2014 to June 2015,precipitation,surface water and groundwater samples were collected in Shiyang River Basin.The main acid ion contents in the samples were analyzed by ion chromatograph.The characteristics of acid ions in different water bodies of Shiyang River basin,seasonal differentiation and its influencing factors were studied.The results shown that all water samples were mildly alkaline and the acid radical ions consisted of SO42-and HCO3-as dominant ions,which accounted for 38.68％ and 33.49％ of total anion,respectively.Obvious variations have been perceived during different seasons,which the highest anion content was in spring and the lowest value in summer.Seasonal variation of groundwater was smaller than that of surface water.The concentration of acid root ion in surface water is much lower than that of groundwater.The weathering of carbonate and the dissolution of evaporite were the main sources of acid ion.In addition,the human activities have caused mild pollution to the water body of the Shiyang River Basin.

通过文献综述和多次野外考察,依据国土资源部针对地质遗迹印发的最新分类标准,对玉龙雪山地质公园内地质遗迹资源进行分类,并运用层次分析法与综合评估方法对地质遗迹资源亚类进行评价.结果表明:地质公园内地质遗迹资源可分为地质剖面、地质构造、地貌景观、环境地质遗迹景观、水体景观5个大类、9个类、15个亚类;评价因子权重文化属性＞自然属性,科研价值=科普价值＞美学价值＞经济社会价值＞典型性＞稀有性＞系统性＞历史文化价值＞自然性;地质遗迹资源亚类划分为三级,其中有Ⅰ级地质遗迹亚类4个、Ⅱ级8个、Ⅲ级3个.总体上,玉龙雪山国家地质公园内地质遗迹类型多样且保存完整,以河流地貌和构造地质遗迹为主要代表,以冰川地质遗迹为主要特色.地质遗迹资源丰富、普遍品质高,有极高的科研、科普价值,尤其是地学方面的研究意义重大.通过对玉龙雪山国家地质公园地质遗迹评价,为地质公园内地质遗迹资源保护和可持续发展提供基础资料和科学参考.

97735 artificial reservoirs have been built in China since 1950s, which could guarantee the supply of urban water and agricultural irrigation. In arid oasis area, only the water of reservoir is available as water resource. The study of hydrochemical characteristics is the prerequisite for evaluating the water quality of domestic water and irrigation water. In the Hongyashan Reservoir, the middle of the Shiyang River Basin and the Tengger desert and Badain Jaran desert, water samples were taken at different points of the lake for about 3 years. The chemical characteristics of the lake water and their influencing factors were studied. The results of the samples for the test have shown that water of the Hongyashan Reservoir is weakly alkaline. And the main compositions of ions in the water are Ca2+ and \(\text{HCO}_{3}^{ - }\), hydrochemical type is Ca–HCO3. In terms of the seasonal variation of Hongyashan Reservoir, except for \(\text{NO}_{3}^{ - }\), the ions in the rest of the water showed roughly the same changeable characteristics in that the composition of ion is higher in summer and autumn, but lower in winter and spring. This is consistent with the seasonal variation in runoff ions throughout the Shiyang River Basin. Ionic characteristics are consistent with the ionic values of dry lakes in the world, which are suitable for urban water and water for irrigation, but are slightly higher than the global lake background standard. Carbonate weathering products are the main source of water ions in Hongyashan Reservoir, and evaporation also affects the ion characteristics of water.

Snow and glaciers are known to be important sources for freshwater; nevertheless, our understanding of the hydrological functioning of glacial catchments remains limited when compared with lower altitude catchments. In this study, a temperate glacial region located in the southeast margin of the Tibetan Plateau is selected to analyse the characteristics of O-18 and D in different water sources and the contribution of glacier-snow meltwater to streamflow. The results indicate that the O-18 of river water ranges from -16.2 parts per thousand to -10.2 parts per thousand with a mean of -14.1 parts per thousand and that the D values range from -117.0 parts per thousand to -68.0 parts per thousand with a mean of -103.1 parts per thousand. These values are more negative than those of glacier-snow meltwater but less negative than those of precipitation. The d-excess values are found to decrease from meltwater to river to lake/reservoir water as a result of evaporation. On the basis of hydrograph separation, glacier-snow meltwater accounts for 51.5% of river water in the Baishui catchment in the melting season. In the Yanggong catchment, snow meltwater contributes 47.9% to river water in the premonsoon period, and glacier meltwater contributes only 6.8% in the monsoon period. The uncertainty in hydrograph separation is sensitive to the variation of tracer concentrations of streamflow components. The input of meltwater to a water system varies with local climate and glacier changes. The results confirm that hydrograph separation using water isotopes is valuable for evaluating the recharge sources of rivers, especially in ungauged glacial regions. This study provides insights into the hydrological processes of glacial catchments on the Tibetan Plateau, which is important for water resource management.

On July 15, 2016, 16 stakes were set up on the surface of the Baishui Glacier No. 1 in Yulong Moun-tain, in order to establish a network for survey glacial movement velocity Handheld difference GPS, Trimble-GeoXT, was used to survey the positions of these stakes. The displacement data of these stakes, from July to October in 2016, were collected and analyzed. The results show that:(1) in a transverse profile the velocity of glacier flow was larger in the mainstream line than that in both sides; in a longitudinal profile, the velocity of glacier flow gradually decreased from the terminus to the firn basin, which was different with general mountain glaciers;in the direction of glacier movement, the velocity vector is mostly moving down along the mainstream line or slightly off the mainstream line;(2) the flow velocity of the glacier was not synchronized with the change of the ablation speed of the glacier, having a lag; ( 3 ) the strongly developed ice crevasses divided the ice bodies, affecting the overall flow of the glacier and making the flow of the glacier more special;(4) the retreat speed of the glacier terminal will continue to accelerate and the retreat trend will continue.

The MIS 3 (Marine Isotope Stage 3) was a special period during the past global climate evolution process.It is important for getting more details about MIS 3 for deeply understanding the regional change of paleo-climate and paleo-environment.The paleo-Daocheng Ice Cap is situated in the southeastern Tibetan Plateau,where the glacial remnants (including the oldest moraines in the Hengduan Mountains) have been well preserved,which provides a natural laboratory to study the glacial history and climate change during Quaternary.Although there has been a lot of work in this area,consensus has not reached on the time of the maximum glaciation and whether glacier advance during MIS 3.In this paper,the possibility of MIS 3 glacial advance in paleoDaocheng Ice Cap is explored based on the climatic records (stalagmites,ice cores,marine sediments and pollen data) and the dating data of glacial advance in the plateau (include the paleo-Daocheng Ice Cap) and around areas during MIS 3.The results showed that glaciers had advanced during 43 ～53 ka (MIS 3).This research will provide new data for climate and environment reconstruction.

Melting of high-elevation glaciers can be accelerated by the deposition of light-absorbing aerosols (e.g., organic carbon, mineral dust), resulting in significant reductions of the surface albedo on glaciers. Organic carbon deposited in glaciers is of great significance to global carbon cycles, snow photochemistry, and air-snow exchange processes. In this work, various snow and ice samples were collected at high elevation sites (4300-4850masl) from Mt. Yulong on the southeastern Tibetan Plateau in 2015. These samples were analyzed for water-soluble organic carbon (DOC), total nitrogen (TN), and water-soluble inorganic ions (WSIs) to elucidate the chemical species and compositions of the glaciers in the Mt. Yulong region. Generally, glacial meltwater had the lowest DOC content (0.39mgL-1), while fresh snow had the highest (2.03mgL-1) among various types of snow and ice samples. There were obvious spatial and temporal trends of DOC and WSIs in glaciers. The DOC and TN concentrations decreased in the order of fresh snow, snow meltwater, snowpit, and surface snow, resulting from the photolysis of DOC and snow's quick-melt effects. The surface snow had low DOC and TN depletion ratios in the melt season; specifically, the ratios were -0.79 and -0.19mgL-1d-1, respectively. In the winter season, the ratios of DOC and TN were remarkably higher, with values of -0.20mgL-1d-1 and -0.08mgL-1d-1, respectively. A reduction of the DOC and TN content in glaciers was due to snow's quick melt and sublimation. Deposition of these light-absorbing impurities (LAPs) in glaciers might accelerate snowmelt and even glacial retreat.

Lijiang is a high-altitude city located on the eastern fringe of the Tibetan Plateau, with complex seasonal atmospheric circulations (i.e. westerly wind, Indian Monsoon, and East Asia Monsoon). Very few previous studies have focused on seasonal variations and sources of organic pollutants in Lijiang. In this study, a four-year air campaign from June 2009 to July 2013 was conducted to investigate the temporal trends and the sources of polycyclic aromatic hydrocarbons (PAHs) and organochlorine compounds [including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs)]. The atmospheric PAH concentrations in winter are 2-3 times of those in summer, probably because of the combined result of enhanced local emission and long-range atmospheric transport (LRAT) during winter. Traffic pollution was the primary local source of PAHs, while biomass burning is the dominant LRAT source. OCPs and PCBs also mainly underwent LRAT to reach Lijiang. The peak concentrations of most of OCPs occurred in pre-monsoon season and winter, which were carried by air masses from Myanmar and India through westerly winds. As compared with other sites of the Tibetan Plateau, without the direct barrier of the Himalaya, Lijiang is easily contaminated by the incursion of polluted air masses.

Lakes are regarded as important nodes in water resources, playing pivotal roles in the regional hydrological cycle. However, the systematic study on lake water balance is scarce in Mt. Yulong region. Here, we study the stable isotope compositions of precipitation, inflowing rivers and lake water to exploit the characteristics of hydrological supply and lake water balance. The results showed that there was a typical spatial distribution of surface isotope in August and April. Relatively high δ18O values with low d-excess were found on the east and west shores of the lake in August and in the middle part of the lake in April. The lowest δ18O with highest d-excess were found in the north and south shores in August and April, respectively. Meanwhile, slight isotopic stratification indicated that the lake water was vertically mixed-well. Subsequently, the evaporation-to-inflow ratios (E/Is) during the two periods were further derived based on the isotope mass balance model. Approximately 51% in August and 12% in April of the water flowing into Lashi Lake underwent evaporation. This study provides a reference for the long-term monitoring and modeling the hydrology processes of the basin, and is important for the regional water resource.