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CHEN BaiLian ZHANG RenHe SUN ShuFen BIAN LinGen XIAO CunDe & ZHANG TingJun Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Chinese Academy of Meteorological Sciences Beijing Graduate University of Chinese Academy of Sciences Beijing Cold Arid Regions Environmental Engineering Research Institute Lanzhou The National Snow Ice Data Center University of Colorado... 《中国科学:地球科学(英文版)》2010,(5)
A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°22′S, 70°22′E), we applied the model to simulate the seasonal temperature variation within a depth of 20 m. Comparison of modeled results with observed snow temperat... 相似文献
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Alpine glaciers usually feature with best hydrothermal condition in mountain climate,and present beautiful glacier scenery,various glacier landforms,rich biodiversity,and easier accessibility,compared with continental glaciers or ice sheets.Nevertheless,Alpine glaciers are more sensitive to climate warming,and climate warming has seriously affected Alpine glaciers and surroundingenvironment.The quality and attractiveness of Alpine glaciers to tourism has been and will continue to be diminished with tourists... 相似文献
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Based on the meteorological and hydrologic data in the Lijang(丽江) basin from 1979 to 2006,variational trend and characteristics of climate change and its effect on runoff in Yanggong(漾弓) River were examined in the study.The results show that the temperature have significantly increased in the drainage basin during the past 28 years.The average temperature increased markedly from 1979 to 2006,and the increase of temperature in winter was higher than those in other seasons.The annual precipitation varied with... 相似文献
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To evaluate the water storage and project the future evolution of glaciers, the ice-thickness of glaciers is an essential input. However, direct measurements of ice thickness are labo-rious, not feasible everywhere, and necessarily restricted to a small number of glaciers. In this article, we develop a simple method to estimate the ice-thickness along flow-line of mountain glaciers. Different from the traditional method based on shallow ice approximation (SIA), which gives a relationship be-tween ice thickn... 相似文献
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In order to study the chemical characteristics of snow-firn pack in Altai Mountains and its environmental significance, a 1.5-m deep snow-firn pack was dug in the accumulation zone (3 300 m a.s.l.) of the Kanas Glacier in August 2009. A total of 15 samples were analyzed for major ions. Results show that the concentrations of major ions in the snow-firn pack are NH4+>SO42->Ca2+>NO3-> Na+>Cl->K+>Mg2+. NH4+ is the dominant cation with a medium value of 4.7 ueq·L-1, accounting for 39.8% of the total cations, an... 相似文献
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1 IntroductionSeaice ,asanimportantcomponentoftheArcticclimatesystem ,hasdrawnsignifi cantscientificinterest.Seaicethicknessanditsmorphologyhavedramaticimpactsono cean atmosphere iceinteractions(Wadhams 1 994;Barryetal.1 993 ;Dickson 1 999;PadhamsandNorman 2 0 0 0 ) ,whichdirectlyaffecttheexchangeprocessandspeedofheatandmassbetweentheoceanandtheatmosphere ,dominatethephysicalmechanicsfea turesofseaice ,andaffecttheseaicemovement&deformationaswellasicefreezing&meltingprocess(Hollandetal.1 99… 相似文献
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我国典型海洋型冰川区高海拔区输出水量变化对气候变暖的响应 总被引:2,自引:0,他引:2
通过丽江盆地气象水文观测资料研究发现: 冰雪消融加剧、融水增加, 漾弓江流域径流量明显上升; 高海拔冰雪区消融期提前, 春季径流增加明显; 高海拔冰雪区的径流输出对漾弓江流域水量平衡的贡献量逐年增加, 体现了全球气候变暖背景下高海拔冰雪区对整个流域水循环的重要性.对海螺沟流域实测气象水文资料的分析也表明, 气候变暖背景下, 该流域冰雪区水量输出也逐年上升.两流域高海拔区输出水量的剧烈增加, 明显响应了气候变暖, 表明了流域水循环的加速, 这必然将对区域的发展和资源开发产生重要影响. 相似文献
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Using lightning locating system based on time-of-arrival technique to study three-dimensional lightning discharge processes 总被引:2,自引:0,他引:2
ZHANG GuangShu WANG YanHui QIE XiuShu ZHANG Tong ZHAO YuXiang LI YaJun & CAO DongJie Laboratory for Climate Environment Disasters of Western China Cold Arid Regions Environmental Engineering Research Institute Chinese Academy of Sciences Lanzhou China Laboratory for Middle Atmosphere Global Environment Observation 《中国科学:地球科学(英文版)》2010,(4)
A time-of-arrival(TOA) system based on GPS technology for locating VHF radiation sources from lightning has been developed and used in observation sites in the northern Shandong Province,China.The 3D images of the lightning progression have been obtained successfully for the first time in China.The 3D-channel evolutions of typical negative CG,positive CG and IC lightning flashes have been discussed together with the data of fast electric field change.It was found that significant differences existed between the negative and positive CG lightning flashes in terms of the initiation and propagation of the radiation sources.The preliminary breakdown of a negative CG lightning flash propagated at a speed about 5.2×104 m/s.The stepped leader of negative CG lightning flashes was trigged by negative initial breakdown.Thereafter,it propagated downward at a speed of 1.3×105 m/s.The initial process of the positive CG lightning flashes was also a propagation process of negative streamer.These streamers propagated dominantly horizontally in the positive charge region and accumulated positive charges at the origin of the lightning,and as a consequence,initiated downward positive streamers.A new type of lightning discharge that was triggered by a narrow bipolar pulse(NBP) is discussed in this study.The NBP was originated at altitude of about 10.5 km in the upper positive charge region.As a distinct difference from normal IC flash,its channels extended horizontally all around and produced a lot of radiation sources.The source power of the NBP could approach 16.7 kW,which is much greater than that of normal lightning discharge ranging between 100 mW and 500 W.The 3D propagation of this new type of lightning discharge was observed and obtained for the first time in China.The possible initiation mechanism of this new type of light-ning is discussed here. 相似文献