Cryospheric change in China

This paper provides an overview of the current status of the cryosphere in China and its changes. Up-to-date statistics of the cryosphere in China are summarized based on the latest available data. There are 46,377 glaciers in China, covering an area of 59,425 km². The glacier ice reserve is estimated to be about 5600 km³ and the annual glacier runoff is about 61.6 × 10⁹ m³. The continuous snow cover extent (> 60 days) in China is about 3.4 × 10⁶ km² and the maximum water equivalent is 95.9 × 10⁹ m³ yr^− 1. The permafrost area in China is about 1.72 × 10⁶ km². The total ground ice reserve on the Qinghai–Tibetan Plateau is estimated to be about 10,923 km³. Recent investigations indicated that glacier areas in China have shrunk about 2–10% over the past 45 yr. Total glacier area has receded by about 5.5%. Snow mass has increased slightly. Permafrost is clearly degrading, as indicated by shrinking areas of permafrost, increasing depth of the active layer, rising of lower limit of permafrost, and thinning of the seasonal frost depth. Some models predict that glacier area shrinkage could be as high as 26.7% in 2050, with glacier runoff increasing until its maximum in about 2030. Although snow mass shows an increasing trend in western China, in eastern China the trend is toward decreasing snow mass, with increasing interannual fluctuations. Permafrost degradation is likely to continue, with one-third to one-half of the permafrost on the Qinghai–Tibetan Plateau anticipated to degrade by 2100. Most of the high-temperature permafrost will disappear by then. The permafrost in northeastern China will retreat further northward.     

中国冰川学和冻土学研究40年进展和展望

回顾４０年来中国冰川学和冻土学从无到有,不断发展壮大,及其所取得的主要研究成果,提出了进一步深入开展冰冻圈与气候变化关系的研究,以及在气候转暖条件下开展干旱与寒区水资源和寒区工程及减灾防灾研究的重要性,并指出了加快发展地理信息科学的必要性。     

Research progress on behaviors and environmental effects of mercury in the cryosphere of the Tibetan Plateau:a critical review

The behavior and fates of environmental pollutants within the cryosphere and the associated environmental impacts are of increasing concerns in the context of global warming.The Tibetan Plateau(TP),also known as the"Third Pole",represents one of the most important cryospheric regions in the world.Mercury(Hg)is recognized as a global pollutant.Here,we summarize the current knowledge of Hg concentration levels,pools and spatio-temporal distribution in cryospheric environments(e.g.,glacier,permafrost),and its transfer and potential cycle in the TP cryospheric region.Transboundary transport of anthropogenic Hg from the surrounding heavily-polluted regions,such as South and Southeast Asia,provides significant sources of atmospheric Hg depositions onto the TP cryosphere.We concluded that the melting of the cryosphere on the TP represents an increasing source of Hg and brings a risk to the TP environment.In addition,global warming acts as an important catalyst accelerating the release of legacy Hg from the melting cryosphere,adversely impacting ecosystems and biological health.Furthermore,we emphasize on the remaining gaps and proposed issues needed to be addressed in future work,including enhancing our knowledge on some key release pathways and the related environmental effects of Hg in the cryospheric region,integrated observation and consideration of Hg distribution,migration and cycle processes at a key region,and uses of Hg isotopic technical and Hg models to improve the understanding of Hg cycling in the TP cryospheric region.     

乌鲁木齐河流域普通民众对冰冻圈变化的感知及适应性对策选择

基于乌鲁木齐河流域普通民众对气候变化及冰冻圈变化感知情况的问卷调查,结合有关监测研究结果,分析了普通民众对流域气候变化及冰冻圈变化的感知情况,探讨了环境变化对流域水资源和农业生产的可能影响.普通民众对气候变化和冰冻圈变化的感知基本与科学监测事实相符.对气候变化和冰冻圈变化条件下普通民众对水资源紧缺的适应措施的分析发现:...     

Distinguishing the Effects of Cryosphere Change in the Background of Climate Change in China

Climate change has major impacts directly on the natural ecosystem and human society, of which the cryosphere is most easily affected be-cause of its frangibility and sensitivity. Similarly, cryosphere change has numerous impacts on the natural ecosystem and human society, which may resemble an indirect influence of climate change. These two types of impacts, in shared fields, are distinguished in space and time by effective mechanisms and processes. Climate change has positive and negative impacts on some systems, which may be adjusted by cryosphere change. These indirect and direct impacts may be distinguished, and then correct policies and measures can be made against these changes.     

青藏高原第四纪冰川的早期记录及其构造与气候含义

综合青藏高原第四纪冰川早期记录的研究进展和典型盆地地层、沉积、古生物、古环境研究的系统成果,扎达盆地香孜组上部冻融层的出现代表了区域的古海拔达到了高原冰缘的高度,即3 500 m以上.这一段地层的时代可能从2.3 Ma前后开始.并与贡巴砾石层下部冰水沉积层的时代基本一致.卓奥友冰期和希夏邦马冰期的时代与扎达盆地沉积结束后,直接覆盖其上的终碛垄和冰碛垄的时代大致相当,展现了这一时期喜马拉雅山脉的山岳冰川进一步发育,也说明喜马拉雅山脉作为青藏高原海拔最高的地区开始冰冻圈的环境很可能在早更新世早中期.川西地区的早更新世的冰川沉积说明东喜马拉雅构造结附近地区这一时期已经抬升至冰冻圈高度,但是,海拨高度与气候环境与喜马拉雅山脉应有不同.具体的时代仍需要深入工作.青藏高原普遍开始冰冻罔记录是在中更新世早期.伴随着全球冰期的到来,这一时期的冰川作用在青藏高原最为发育和广泛.这些暗示着青藏高原在中更新世早期整体性地较快速抬升进入冰冻圈,即海拔3 500 m以上.详细的过程仍有待深入研究.     

气候变化与冰川演变的研究进展

在气候变化影响的诸环境系统中，冰冻圈首当其冲。冰冻圈不仅对全球变暖的敏感性最高、变化最快、最明显，而且人类对它的变化很难采取有效的防范措施，因此，它被认为是最容蝗受到气候变化损害的脆弱环，尤其是山地冰川，其进退这变化就是对气候变化的响应，正因如此，对冰川及其与气候变化的关系研究越来越为人们所关注。     

祁连山黑河径流变化特征及影响因素研究

基于黑河流域径流、气象和土地利用类型等资料,采用弹性系数等方法研究了黑河径流变化特征及影响因素。结果表明：（1） 1990年后黑河流域径流量增加趋势明显加速,并且在黑河干流表现最为明显,1957—1990年莺落峡站径流量增加速率为0.75×10⁸ m³·(10a)^-1,而1991—2020年其增加速率为2.60×10⁸ m³·(10a)^-1,后者是前者的3.47倍,并且黑河全流域1990年后径流量增加主要发生在夏季和秋季,较1990年前分别增加了7.07%和26.58%。（2） 径流对气候变化的响应在夏季最为敏感,并且降水是导致径流增多的主要气候因素,夏季降水量增多1.000%,同期径流量平均增多0.741%（P<0.01）。（3） 2020年较1980年黑河流域耕地和建设用地面积相对增幅分别为24.20%和71.43%;草地和未利用土地面积相对降幅分别为1.30%和5.28%。径流量与林地面积、建设用地面积呈正相关,而径流量与草地面积呈负相关。研究结果可以为黑河流域水资源的科学管理、优化配置和后续生态工程的实施提供参考。     

Determining annual cryosphere storage contributions to streamflow using historical hydrometric records

Alpine glaciers and perennial snow fields are important hydrologic elements in many mountain environments providing runoff during the late summer and during periods of drought. Because relatively long records of glacier mass–balance data are absent from many glacierized catchments, it remains unclear to what extent shrinking perennial snow and glaciers have affected runoff trends from these watersheds. Here, we employ a hydrograph separation technique that uses a double mass curve in an attempt to isolate changes in runoff due to glacier retreat and disappearance of perennial snow. The method is tested using hydrometric data from 20 glacierized and 16 nonglacierized catchments in the Columbia Basin of Canada. The resulting estimates on cryosphere storage contribution to streamflow were well correlated to other regional estimates on the basis of measurements as well as empirical and mechanistic models. Annual cryosphere runoff changed from +19 to ?55% during the period 1975–2012, with an average decline of 26%. For August runoff, these changes ranged from +17 to ?66%, with an average decrease of 24%. Reduction of cryosphere contributions to annual and late summer flows is expected to continue in the coming decades as glaciers and the perennial snow patches shrink. Our method to isolate changes in late summer cryospheric storage contributions can be used as a first order estimate on changes in glacier contributions to flow and may help researchers and water managers target watersheds for further analysis.     

冰冻圈变化及其对中国气候的影响

The cryosphere is a prominent factor in and an indicator of global climate change. It serves one of the most direct and sensitive feedbacks in the climate system, and plays an important role in the earth＇s climate system. Cryospheric research has attracted unprecedented attention in the context of global warming, and is now one of the most active areas in studies of global change, sustainable development, and the climate system. This paper addresses recent and potential future changes in the cryosphere both globally and within China under the background of global warming. Particular attention is paid to progress toward understanding the impacts of the Tibetan Plateau and Eurasian snow cover, Arctic and Antarctic sea ice, and permafrost and glaciers on Chinese climate. The future development of cryospheric research in China is also discussed.