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41.
42.
中国冰冻圈文化服务专题区划研究 总被引:1,自引:0,他引:1
本文以中国冰冻圈服务综合区划、自然和人文地理区划等理论、方法为基础,综合中国冰冻圈主要组成要素(冰川、冻土、积雪)及其社会文化要素(民族、历史、聚落、旅游文化和行政区划),采用相似性与差异性、综合性与主导性、等级性与逻辑性和空间连续与行政边界相结合的方法,提出了“文化服务+文化产业+经济开发”导向的中国冰冻圈文化服务专题区划方案。根据空间聚类方法和专家判断,将其划分为青藏高原冰川—冻土—积雪文化区、西北冰川—积雪文化区、东北冻土—积雪文化区、北方积雪文化区和南方积雪文化区5个一级区划大区,依据文化与地域要素异质性原则,再细分为12个二级区划亚类和51个三级区划基本类型。专题区划方案与中国冰冻圈空间分布、中国自然地理综合区划、中国人文地理综合区划等的吻合度较高,体现了冰冻圈组成要素与冰冻圈区域文化要素的依存关系及区域空间异质性规律。本文深化了对中国冰冻圈文化服务及其空间异质性的认知,可为冰冻圈文化保护、传承、发扬,以及不同区域冰冻圈文化、旅游产业的开发及相关产业的运营、管理提供科学依据。 相似文献
43.
Progress on observation of cryospheric components and climate-related studies in China 总被引:1,自引:0,他引:1
Systematic studies on the cryosphere in China started in the late 1950s. Significant achievements have been made by continuous investigation of glacier inventories, frozen ground observations, paleo-climate analyses of ice cores, process studies and the modeling of cryopsheric/atmospheric interactions. The general facts and understanding of these changes include: (1) Solid precipitation, including the number of days with frost and hail storms, shows a decreasing tendency over the past half century. (2) In most areas glaciers are retreating or have completely vanished (〉80%), some glaciers are still advancing (5%-20% depending upon time period). The annual glacial melt water has been increasing since the 1980s. This increased supply of melt water to river runoff in Northwest China is about a 10%-13%. (3) The long-term variability of snow cover in western China is characterized by a large inter-annual variation superimposed on a small increasing trend. Snow cover variability in the Qinghai-Xizang Plateau (QXP) is influenced by the Indian monsoon, and conversely impacts monsoon onset and strength and eventually the drought and flood events in middle-low reaches of Yangtze River. (4) Frozen ground, including permafrost, is decaying both in QXP and in Northeast China. The most significant changes occurred in the regions with thickest seasonal frozen ground (SFG), i.e., inland QXP, then northeastern and northwestern QXP. The cold season air temperature is the main factor controlling SFG change. The increase of ground surface temperatures is more significant than air temperature. (5) The sea ice coverage over the Bohai Sea and Yellow Sea has deceased since the 1980s. (6) River ice duration and ice thickness is also decreasing in northern China.
In 2001, the Chinese National Committee of World Climate Research Program/Climate and Cyosphere (WCRP/CliC) (CNC-CliC) was organized to strengthen research on climate and cryosphere in China. Future monitoring of the cryosphe 相似文献
In 2001, the Chinese National Committee of World Climate Research Program/Climate and Cyosphere (WCRP/CliC) (CNC-CliC) was organized to strengthen research on climate and cryosphere in China. Future monitoring of the cryosphe 相似文献
44.
PHILIP DELINE MARIE GARDENT FLORENCE MAGNIN LUDOVIC RAVANEL 《Geografiska Annaler: Series A, Physical Geography》2012,94(2):265-283
One of the most glacierized areas in the European Alps, the Mont Blanc massif, illustrates how fast changes affect the cryosphere and the related morphodynamics in high mountain environments, especially since the termination of the Little Ice Age. Contrasts between the north‐west side, gentle and heavily glaciated, and the south‐east side, steep and rocky, and between local faces with varying slope angle and aspect highlight the suitability of the study site for scientific investigations. Glacier shrinkage is pronounced at low elevation but weaker than in other Alpine massifs, and supraglacial debris covers have developed over most of the glaciers, often starting in the nineteenth century. Lowering of glacier surface also affects areas of the accumulation zone. While modern glaciology has been carried out in the massif for several decades, study of the permafrost has been under development for only a few years, especially in the rock walls. Many hazards are related to glacier dynamics. Outburst flood from englacial pockets, ice avalanche from warm‐based and cold‐based glaciers, and rock slope failure due to debuttressing are generally increasing with the current decrease or even the vanishing of glaciers. Permafrost degradation is likely involved in rockfall and rock avalanche, contributing to the chains of processes resulting from the high relief of the massif. The resulting hazards could increasingly endanger population and activities of the valleys surrounding the Mont Blanc massif. 相似文献
45.
1980年以来冰冻圈对气候变暖响应的若干证据 总被引:11,自引:1,他引:11
进入80 年代,气候较前10-20年显示出明显的变暖趋势。冰冻圈对此迅速作出了反应:出岳冰川物质平衡80年代较60-70年代平均减少近173mm,相当于冰川敏感值升高约0.38℃;对气候变化反应敏感的小冰川退缩比例增加了15-20%;冰土层中温度亦显示出强劲增势,冰土隔深、冻土界退的变化已有所表现。 相似文献
46.
A geometrical model, including different geometrical shapes influencing thermal conductivity of snow is proposed. The geometrical
model has been assumed to comprise of unit cells having solid (ice) inclusion as an aggregation of spherical, cylindrical
or cubical shapes with vertical connection, arranged in a cubic packing. From the geometrical model and one-dimensional heat
transfer theory, the effective thermal conductivity has been computed. For this purpose, coupled one-dimensional heat transfer
equations have been solved for steady-state condition to account for conduction in ice, conduction in air and latent heat
transfer due to water vapour sublimation through air. The model demonstrates the dependency of thermal conductivity on density,
grain-spacing, grain contact ratio and temperature. Spherical inclusions give highest conductivity while cubical inclusion
estimates lowest value for the same density. Thermal conductivity has been found increasing sharply near to the packing density
for all three shapes. Empirical model results and results obtained from existing microstructure based models have also been
compared with the present model. 相似文献
47.
Observation and estimation of evaporation from the ground surface of the cryosphere in eastern Asia 总被引:1,自引:0,他引:1
The characteristics of evaporation from the ground surface of Asian cryosphere sites are presented, as estimated by the lysimeter method, a profile method, and a heat budget method. The observation sites were located on the eastern Tibetan Plateau, in the Qilian and Tianshan Mountains of China, and in eastern Siberia. The lysimeter method has been demonstrated to be a reliable observation technique for estimating daily evaporation from the land surface, given suitable experiment design and operation. Daily mean evaporation varied within the range of 0·3 to 3·5 mm on the permafrost surface, and regional differences in evaporation were strongly related to surface soil moisture. Locally, topography, by way of its influence on surface soil moisture, was found to control evaporation systematically. Seasonality of ground evaporation in permafrost regions is dominated by thaw–freeze cycles at the surface; evaporation from the melting permafrost surface is up to four to seven times greater than that from frozen ground. In forested terrain, the interception of precipitation can reduce daily evaporation by 60 to 70%. Sublimation from the snow surface was observed at some sites in the range of 0·2 to 1·0 mm daily; atmospheric conditions, such as wind speed and saturation deficit, were dominant factors in determining snow sublimation. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
48.
冰冻圈变化对经济社会系统的综合影响及其适应性管理策略 总被引:4,自引:4,他引:0
冰冻圈是气候系统影响最直接和最敏感的圈层。在全球变化背景下,冰冻圈变化与生物圈、岩石圈、水圈、大气圈、人类圈之间的相互作用日趋加剧。特别地,冰冻圈快速变化对其影响区经济社会系统产生了广泛而深刻的负面影响,甚至危及人类福祉、经济社会系统的健康、和谐、持续发展。鉴于冰冻圈区位劣势及其较为落后的经济水平,其应对冰冻圈变化的能力极为有限。目前,适应仍然是冰冻圈应对气候变化的主要途径。冰冻圈变化对经济社会系统的综合影响分析是适应冰冻圈快速变化的基础,其适应性管理战略则是减轻冰冻圈快速变化不利影响、降低自然和经济社会系统防御其不利影响脆弱性的最终目标。 相似文献
49.
In order to discuss the characteristics of sea ice change of strong signal area on Antarctic and Arctic and the correlation between the thermal state on the land surface of Tibetan Plateau and the atmosphere circulation of North Hemisphere or the climate changes in China, and to study the feedback mechanism among “three-pole” factors, the earlier stage “three-pole” strong signal characteristics by using statistic methods such as teleconnection,which affect the regional climate changes in China and East Asia. The cross-correlation feature and coupling effect between ice caps of North and South pole and water-thermal state on Tibetan Plateau surface are discussed as well. The contribution of three-pole's earlier stage factors to China's summer climate change and the influence of its dynamic structure are compared here. The formation mechanisms of global climate change and regional climate change of China are investigated from the aspect of qualitative correlation mode of global sea-land-air-ice. 相似文献
50.