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51.
2013—2015年由中国国土资源航空物探遥感中心牵头开展了中国地质调查局地质调查项目“西北边境地区国土资源遥感综合调查”,我国西北边境高寒、高海拔地区的冰冻圈遥感调查是其中一项重要内容。冰冻圈遥感调查的主要进展有: 基于地形地貌、地温分布和坡度坡向特征等综合信息完成了藏北等地区的多年冻土范围调查; 利用高分1号(GF-1)宽幅数据和Landsat数据,对2013年1月—2014年12月期间阿里西部地区近10 000 km2的积雪覆盖情况进行了连续19个期次的动态监测; 基于1999—2013年间的Landsat多期影像,对班公湖和斯潘古尔湖冷季6个月份的湖冰覆盖情况进行了动态调查。  相似文献   
52.
Glacial retreat and the thawing of permafrost due to climate warming have altered the hydrological cycle in cryospheric‐dominated watersheds. In this study, we analysed the impacts of climate change on the water budget for the upstream of the Shule River Basin on the northeast Tibetan Plateau. The results showed that temperature and precipitation increased significantly during 1957–2010 in the study area. The hydrological cycle in the study area has intensified and accelerated under recent climate change. The average increasing rate of discharge in the upstream of the Shule River Basin was 7.9 × 106 m3/year during 1957–2010. As the mean annual glacier mass balance lost ?62.4 mm/year, the impact of glacier discharge on river flow has increased, especially after the 2000s. The contribution of glacier melt to discharge was approximately 187.99 × 108 m3 or 33.4% of the total discharge over the study period. The results suggested that the impact of warming overcome the effect of precipitation increase on run‐off increase during the study period. The evapotranspiration (ET) increased during 1957–2010 with a rate of 13.4 mm/10 years. On the basis of water balance and the Gravity Recovery and Climate Experiment and the Global Land Data Assimilation System data, the total water storage change showed a decreasing trend, whereas groundwater increased dramatically after 2006. As permafrost has degraded under climate warming, surface water can infiltrate deep into the ground, thus changing both the watershed storage and the mechanisms of discharge generation. Both the change in terrestrial water storage and changes in groundwater have had a strong control on surface discharge in the upstream of the Shule River Basin. Future trends in run‐off are forecasted based on climate scenarios. It is suggested that the impact of warming will overcome the effect of precipitation increase on run‐off in the study area. Further studies such as this will improve understanding of water balance in cold high‐elevation regions.  相似文献   
53.
全球山地冰冻圈变化、影响与适应   总被引:1,自引:0,他引:1  
冰冻圈是高山地区不可或缺的重要组成部分,居住着全球约10%的人口。近几十年来,冰冻圈变化对山区和周围地区的自然和人类系统产生了广泛而深远的影响,对海洋也发挥着重要作用。IPCC最新发布的《气候变化中的海洋和冰冻圈特别报告》(SROCC)指出,过去几十年全球高山区气温显著升高,使山地冰冻圈发生了大范围显著退缩。观测到的山地(特别是低海拔山区)积雪期缩短、雪深和积雪覆盖范围减小;冰川物质持续亏损,其中全球最大的冰川负物质平衡出现在南安第斯山、高加索山和欧洲中部,亚洲高山区冰川负物质平衡最小;多年冻土温度升高、厚度减薄,地下冰储量减少;河、湖冰持续时间缩短。随着气候持续变暖,山地冰冻圈在21世纪仍将呈继续退缩状态。到21世纪末,低海拔山区积雪深度和积雪期将减少,冰川物质损失继续增加,多年冻土持续退化。冰冻圈变化已经或将改变山地灾害发生频率和强度,并对水资源、生态系统和经济社会系统产生重要影响。应对山地冰冻圈变化应从管理和优化利用冰冻圈资源、加强冰冻圈变化灾害风险的有效治理、增强国际合作及公约制定等适应策略着手开展,增强适应能力,从而有益于推动山地生态系统和经济社会系统可持续发展。  相似文献   
54.
The cryosphere is one of the climate system component which plays an important role in the global biogeochemical mercury cycling. Anthropogenic mercury has been transported to remote cold and high regions worldwide through atmospheric circulation,and then transformed into methylmercury in the cryosphere. As one of the highly toxic environmental pollutants,methylmercury can be greatly bioaccumulated and biomagnified through the food web,which potentially poses threats to human and wildlife as well as the global cryospheric en⁃ vironments. In order to gain a full picture of research progress on methylmercury in the cryosphere,our study comprehensively summarized the concentration levels and analytical methods of methylmercury,and biogeo⁃ chemical processes such as the migration,transformation and fate of methylmercury in various cryospheric envi⁃ ronments including glacier,permafrost,snow ice and sea ice. We particularly made the literature review of mi⁃ crobial mercury methylation and evaluated the risk of methylmercury exposure to human and wildlife in the cryo⁃ sphere. Meanwhile,we focus on distribution,behavior,and environmental effects of methylmercury in the cryosphere against the backdrop of climate change,which is essential for assessing the exposure risk of methyl⁃ mercury to humans and wildlife. Perspectives of methylmercury researches in the cryosphere have also been highlighted in this review,though there is existing a knowledge gap of biogeochemical methylmercury cycling in the low temperature environments which merits further study. © 2023 The Author(s).  相似文献   
55.
The Anthropocene is proposed as a new interval of geological time in which human influence on Earth and its geological record dominates over natural processes. A major challenge in demarcating the Anthropocene is that the balance between human‐influenced and natural processes varies over spatial and temporal scales owing to the inherent variability of both human activities (as associated with culture and modes of development) and natural drivers (e.g. tectonic activity and sea level variation). Against this backdrop, we consider how geomorphology might contribute towards the Anthropocene debate by focusing on human impact on aeolian, fluvial, cryospheric and coastal process domains, and how evidence of this impact is preserved in landforms and sedimentary records. We also consider the evidence for an explicitly anthropogenic geomorphology that includes artificial slopes and other human‐created landforms. This provides the basis for discussing the theoretical and practical contributions that geomorphology can make to defining an Anthropocene stratigraphy. It is clear that the relevance of the Anthropocene concept varies considerably amongst different branches of geomorphology, depending on the history of human actions in different process domains. For example, evidence of human dominance is more widespread in fluvial and coastal records than in aeolian and cryospheric records, so geomorphologically the Anthropocene would inevitably comprise a highly diachronous lower boundary. Even to identify this lower boundary, research would need to focus on the disambiguation of human effects on geomorphological and sedimentological signatures. This would require robust data, derived from a combination of modelling and new empirical work rather than an arbitrary ‘war of possible boundaries' associated with convenient, but disputed, ‘golden’ spikes. Rather than being drawn into stratigraphical debates, the primary concern of geomorphology should be with the investigation of processes and landform development, so providing the underpinning science for the study of this time of critical geological transition. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
56.
从第三极到北极: 气候与冰冻圈变化及其影响   总被引:10,自引:10,他引:0  
第三极和北极地区对于区域和全球环境、 社会经济以及国家战略的重要性日益凸现。通过对第三极和北极气候与冰冻圈研究的现状、 趋势进行梳理总结, 为未来的系统研究提供借鉴。结果显示, 第三极和北极气候系统与冰冻圈正在发生显著变化并预计将持续下去。第三极和北极地区气温在以全球平均升温速度两倍的速率变暖, 且在20世纪70年代以来, 变化总体趋势高度一致; 降水变化总体呈增加趋势, 但变率和不确定性较大; 极端事件(尤其是极端降水)的频率增加; 积雪范围总体上呈现减少趋势, 雪水当量、 积雪天数的变化存在区域和周期性差异; 多年冻土温度升高, 活动层厚度增加, 亦呈现较大的区域差异。这些变化不仅对生态、 水文、 碳循环产生重要影响, 而且对基础设施、 社会经济以及人类健康产生不可忽视的影响, 包括重金属污染、 食品安全等。气候及冰冻圈快速变化会通过反照率反馈、 水汽反馈等机制被放大, 并通过一系列大气及海洋环流过程, 对周边乃至全球气候系统产生广泛影响。目前第三极和北极研究中面临的重要共同问题包括极度稀疏的地面观测资料、 模型物理机制和精细化描述不足以及缺少与周边地区乃至全球系统关联的量化研究和可靠证据。这些问题的解决都需要依赖地面监测网络的扩展以及对冰冻圈和气候系统物理过程理解的提升。从第三极到北极, 不仅是研究视角的扩大, 更是全面理解第三极和北极在地球系统中作用的必经之路。  相似文献   
57.
Deng  Haijun  Chen  Yaning  Li  Yang 《地理学报(英文版)》2019,29(1):84-100
Journal of Geographical Sciences - Glaciers and snow are major constituents of solid water bodies in mountains; they can regulate the stability of local water sources. However, they are strongly...  相似文献   
58.
Mountain glacier-related hazards occur worldwide in response to increasing glacier instability and human activity intensity in modern glacierized regions. These hazards are characterized by their spatial aggregation and temporal repeatability. Comprehensive knowledge about mountain glacier-related hazards is critical for hazard assessment, mitigation, and prevention in the mountain cryosphere and downstream regions. This article systematically schematizes various mountain glacier-related hazards and analyzes their inherent associations with glacier changes. Besides, the processes, manifestations, and mechanisms of each of the glacier-related hazards are summarized. In the future, more extensive and detailed systematic surveys, for example, considering integrated ground-air-space patterns, should be undertaken for typical glacierized regions to enhance existing knowledge of such hazards. The use of coupled numerical models based on multi-source data is challenging but will be essential to improve our understanding of the complex chain of processes involved in thermal-hydrogeomorphic glacier-related hazards in the mountain cryosphere.  相似文献   
59.
近年来,青藏高原冰川持续退缩,显著影响区域气候与生物地球化学循环.作为重要的营养元素,氮在生态系统中的循环备受关注.冰川中含氮化合物的迁移转化是冰冻圈地区氮循环的重要环节.基于青藏高原地区冰川氮记录研究,综述了近年来冰芯氮记录的历史变化,指出不同区域的变化趋势存在差异,认为一定程度上受亚洲地区人类活动排放污染物的影响....  相似文献   
60.
RogerG.Barry 《冰川冻土》2002,24(5):523-525
The cryosphere is an integral part of the global climate system, however, many aspects of the cryosphere have not been fully covered within WCRP. Issues relating to potential changes in the climate cryosphere system become more and more important in order to describes research and coordination initiatives required to integrate fully studies of impact and response of the cryosphere to climate change. The article also indicates the recent progress of CliC, and its future plan.  相似文献   
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