检索结果-南通市图书馆

Identification of ice Elevation Change of the Shuiguan River No.4 Glacier in the Qilian Mountains,china

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2010年第4期7卷 375-379页

作者： LI Jing LIU Shiyin SHANGGUAN Donghui ZHANG Yinsong State key laboratory of Cryospheric sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

GPS measurement,an effective method for surveying glacier surface topography,has been applied in some glaciers for many *** Shuiguan River No.4 glacier,a small glacier with its area of 1.84 km2 in 1972,located in the east of the Qilian Mountains,china,was selected to study its ice elevation change using GPS measurement in *** study was conducted on the ablation area with GPS-measured area 0.5.*** ice elevation change of the glacier was obtained by comparing the DEM obtained by a 1:5. 000 topographic map made in 1972 with the DEM by GPS-measured data acquired in *** differences of the two DEMs showed the thinning condition of the glacier was *** mean thinning was 15.8 m with the mean thinning rate of 0.42±0.22 m a-1 for 1972-2007 in the measurement area,which equaled 0.38±0.20 m yr-1 in water equivalent(w.e.).The prominent thinning occurred on the south part of the glacier,which was the area near the glacier terminus with the maximum thinning of 41±8 *** the thinning value of 15.8 m for the glacier area below 4640 m a.s.l.,the wasting ice mass was calculated to be 6.4±3.2×10-3 km3 for 1972-2007,corresponding to 5.7±2.8×10-3 km3 w.e.,which meant that the montane runoff released by the glacier was at least 5.7±2.8×106 m3 between 1972-2007.

关键词： GPS RTK DEM Glacier mass balance Mountane runoff

CLIMATIC VARIATIONS IN china OVER THE LAST 2000 YEARS

在线全文

学校读者我要写书评

暂无评论

chinese Geographical Science 2001年第2期11卷 97-103页

作者： YANG Bao1, SHI Ya-feng2, LI Heng-peng2 (1. cold and arid regions environmental and engineering {5. institute, the chinese academy of sciences,lanzhou 730000, P.R. china 2. institute of Geography and Limnology, the chinese academy of sciences cold and arid regions environmental and engineering {5. institute the Chinese Academy of Sciences Lanzhou P. R. China institute of Geography and Limnology the Chinese Academy of Sciences Nanjing P. R. China

A compilation of paleoclimate records from ice core, tree-rings, lake sediments and historical documents provides a view of temperature change in china over the recent 2000 years. For all-china temperature reconstruction, six sub-stages are identified for the last two millennia. Around AD 0－240, AD 800－1100, AD 1320－1400 and the period from AD 1880 on were warm while around AD 240－800, AD 1100－1320, AD 1400－1880 were cold. Also, temperature varied from region to region in each of the warm or cold periods. The Eastern Han warm period (0－AD 240), the cold period covering the span of Wei, Jin, and the Southern and Northern Dynasties, the MWP (AD 800－1100) and succeeding LIA occurred in eastern china and the Qilian Mountains. Only the first two climatic events were recorded in Guliya ice core while the so-called MWP and LIA was far weaker. Also, the warming between AD 800 and 1100 didn′t occur in the south of Xizang (Tibet) Plateau. Instead, the southern Xizang Plateau experienced warming in AD 115.－1400. The aggregated china temperature agrees well with North-hemisphere temperature in the past millennia, indicating close relationship of temperature changes between china and North-hemisphere.

关键词： climatic variations the last two millennia china

Grain size record of microparticles in the Muztagata ice core

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2006年第1期49卷 10-17页

作者： WU Guangjian1,2, YAO Tandong1,2, XU Baiqin1,2, LI Zheng2, TIAN Lide1,2, DUAN Keqin2 & WEN Linke2 1. laboratory of environment and Process on Tibetan Plateau, institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085.{5. 2. key laboratory of Cryosphere and environment, Jointly Established by cold and arid regions environmental and Engi-neering research institute and institute of Tibetan Plateau research, chinese academy of sciences and chinese academy of Meteorological sciences,{5. Meteorological Administration, lanzhou 730000,{5. laboratory of environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China key laboratory of Cryosphere and environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China

The dust transport and sediment characteristics are discussed based onanalysis of mi-croparticle size and size distribution in the Muztagata ice core at 635. m a.s.I. Thefiner particles with diameter of 1—5.μm are the dominant fraction in number, while middle andcoarse particles mainly contribute to the total volume. The lognormal distribution characteristicscan be seen for some high concentration samples, showing that model size and standard variation aregreater than that in the Greenland ice cores. However, size-volume distribution of some lowconcentration samples is abnormal. Those distributions reflect the dust deposit process in highmountain glaciers at mid-low latitudes and show differences from those in polar ice sheet.

关键词： Muztagata, ice core, microparticle, dust, size distribution.

Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming—Taking Xinjiang Glaciated Region as Example

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2005年第4期2卷 306-312页

作者： WANG Xin XIE Zichu LIU Shiyin TAO Jianjun HAN Yongshun YANG Yuelong research institute of Geo-spatial Information Science Hunan University of Science ＆ Technology Xiangtan 411201 Hunan China key laboratory of ice core and cold Region＇s {5. Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China institute of Resources and environment Hunan Normal University Changsha 410081 China institute of Tibetan Plateau research CAS Beijing 100029 China

The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 5. years, although there were surely some uncertainties in precipitation predictions. On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state （ELAo）, a functional model of the glacier system responding to climate changes was established, and it simultaneously involved the rising of summer mean temperature and increasing of mean precipitation. The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01, 0.03 and 0.05.K/year indicated that the precipitation increasing would play an evident role in glacier system responding to climate change： if temperature become 1 ℃ higher, the precipitation would be increased by 10%, which can slow down the glaciers retreating rate in the area by 4 %, accelerate runoff increasing rate by 8 % and depress the ELAo rising gradient by 24 m in northern Xinjiang glacier system where semi-continental glaciers dominate, while it has corresponding values of only 1%, 5.% and 18m respectively in southern Xinjiang glacier system, where extremely continental glaciers dominate.

关键词： Glacier system climate warming precipitation increasing role

Influence of Degree-Day Factor Variation on the Mass Balance of Glacier No. 1 at the Headwaters of ürümqi River,china

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2013年第6期24卷 1008-1022页

作者：崔玉环叶柏生王杰刘友存 State key laboratory of Cryospheric sciences Cold and Arid Regions Environment and Engineering Research InstituteChinese Academy of Sciences School of Resources and environmental engineering Anhui University key laboratory of Water Resources and environment Tianjin Normal University

The degree-day factor （DDF） is a key parameter in the degree-day model, and the varia- tions in DDF have the significant effects on the accuracy of glacier mass balance modeling. In this study, Glacier No. 1 at the headwaters of Uriimqi （-~O）~Z~=） River in china was selected, and the estimated DDF by stakes-observed mass balance and meteorological data from 1983-2006 was used to analyze the spatio-temporal variability of DDF and its influencing factors, such as climate condition, surface fea- ture, and topography. Then, the ablations from the 1980s to 2000s were estimated using the degree-day modei, and the ablation change from the 1980s to 2000s was divided into the changes caused by climate change and by the ice-surface feature. The following results were obtained：（1） The annual change in DDF for snow was not obvious, whereas that for ice increased, and the increasing trend on the lower glacier was more significant than that on the upper glacier because of decreased albedo caused by vari- ations in ice-surface feature; （2） The DDF for ice clearly decreased with altitude by approximately 0.046 and 0.043 mm.＇C-l-d-Lm-1 on the east and west branches, respectively, and the DDF of the west branch was obviously larger than that of the east branch in the same altitude belt; （3） the changes in mass balance in the summers from the 1980s to 2000s were -391 and -467 mm on the east and west branches, respectively. Among the total changes, the components directly caused by climate change were -193 and -198 mm, whereas those indirectly caused by ice-surface feature change were -198 and -269 mm on the east and west branches, respectively.

关键词： degree-day factor mass balance,Glacier No. 1 climate change.

Distribution of Borehole Temperature at Four High-altitude Alpine Glaciers in Central Asia

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2009年第3期6卷 221-227页

作者： LIU Yaping HOU Shugui WANG Yetang SONG Linlin State key laboratory of Cryospheric sciences Cold andArid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences China Graduate University of chinese academy of sciences Beijing 100049 China

The distribution of borehole temperature at four high-altitude alpine glaciers was investigated. The result shows that the temperature ranges from -13.4℃ to -1.84℃, indicating the glaciers are cold throughout the boreholes. The negative gradient （i.e., the temperature decreasing with the increasing of depth） due to the advection of ice and climate warming, and the negative gradient moving downwards relates to climate warming, are probably responsible for the observed minimum temperature moving to lower depth in boreholes of the Gyabrag glacier and Miaoergou glacier compared to the previously investigated continental ice core borehole temperature in West china. The borehole temperature at 10m depth ranges from -8.0℃ in the Gyabrag glacier in the central Himalayas to -12.9℃ in the Tsabagarav glacier in the Altai range. The borehole temperature at 10 m depth is 3-4 degrees higher than the calculated mean annual air temperature on the surface of the glaciers and the higher 10 m depth temperature is mainly caused by the production of latent heat due to melt-water percolation and refreezing. The basal temperature is far below the melting point, indicating that the glaciers are frozen to bedrock. The very low temperature gradients near the bedrock suggest that the influence of geothermal flux and ice flow on basal temperature is very weak. The low temperature and small velocity of ice flow of glaciers are beneficial for preservation of the chemical and isotopic information in ice cores.

关键词： Borehole temperature Glacier CentralAsia Climate warming

A 290-a record of atmospheric circulation over the North Pacific from a Mt. Logan ice core, Yukon Territory

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2005年第4期24卷 81-90页

作者： KANG Shichang MAYEWSKI Paul A YAN Yuping institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China Climate Change institute University of Maine Orono ME 04469 USA laboratory of Cryosphere and environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China National Climate Center Beijing 100081 China

Calibrations between sodium （Na^＋） concentrations from a Mt. Logan ice core and sea level pressure （SLP） series show that Na^＋ concentrations are closely correlated with the autumn-time （September-October-November） Aleutian low （AleuLow）. A deepening of the AleuLow strengthens the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. The Mt. Logan Na^＋ record is used to develop a 292 a （1688-1979） reconstruction of the AleuLow revealing a dramatic intensification of atmospheric circulation over the North Pacific region since the 20th century. Mean SLP of the AleuLow was about 1 hPa lower during the 20th century than during prior periods. The strongest deepening of the AleuLow appeared in the 195.s. Significant correlations are also found between the Mt. Logan AleuLow proxy series and the Pacific decadal oscillation （PDO） and Pacific circulation （PC） index during the 20th century. Evolutionary spectral analysis of the proxy record shows significant periodicities from 15.to 30 a consistent with PDO fluctuations and the bidecadal oscillation of North Pacific atmosphere-ocean circulation. A period of 11 a in the AleuLow record may be associated with the Schwabe 11-a cycle of sunspot activity. Additional longer ice core records from this region will aid in the efforts to further understand the climatic change over the North Pacific region.

关键词： atmospheric circulation ice core records North Pacific

Hydrological Characteristics of the Rongbuk Glacier Catchment in *** Region in the Central Himalayas,china

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2010年第2期7卷 146-156页

作者： LIU Weigang REN Jiawen QIN Xiang LIU Jingshi LIU Qiang CUI Xiaoqing WANG Yetang State key laboratory of Cryospheric sciences Cold andArid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 10085 China

From 8 April to 11 October in 2005. hydrological observation of the Rongbuk Glacier catchment was carried out in the Mr. Qomolangma （Everest） region in the central Himalayas, china. The results demonstrated that due to its large area with glacier lakes at the tongue of the Rongbuk Glacier, a large amount of stream flow was found at night, which indicates the strong storage characteristic of the Rongbuk Glacier catchment. There was a time lag ranging from 8 to 14 hours between daily discharge peaks and maximum melting （maximum temperature）. As melting went on the time lag got shorter. A high correlation was found between the hydrological process and daily temperature during the ablation period. The runoff from April to October was about 80% of the total in the observation period. Compared with the discharge data in 195., the runoff in 2005.was much more, and the runoff in June, July and August increased by 69%, 35. and 14%, respectively. The rising of temperature is a major factor causing the increase in runoff. The discharges from precipitation and snow and ice melting are separated. The discharge induced by precipitation accounts for about 20% of the total runoff, while snow and ice melting for about 80%.

关键词： Central Himalayas Mt. Qomolangma Rongbuk Glacier Hydrological characteristics

PROXY RECORD OF A FIRN-core FROM AN ALPINE GLACIER AND ITS IMPLICATION TO RECENT GLACIO-CLIMATIC VARIATIONS ON MT. YULONG, SOUTHEASTERN PART OF TIBETAN PLATEAU

在线全文

学校读者我要写书评

暂无评论

地学前缘 2000年第S1期7卷 391-391页

作者： He Yuanqing, Yang Meixue[WT5.5.BX](laboratory of ice core and cold Region environment, cold and arid regions environmental and engineering research institute, chinese academy of sciences, lanzhou 730000, china)

Mt. Yulong, located in the eastern part of Tibetan Plateau, is the southmost present glaciation area both in china and Europe\|Asia continent,where distributes 19 typical sub\|tropics temperate glaciers. In the summer of 1999, a firn core, 10 10m long to the glacier ice, was successfully recovered in the accumulation area at the largest glacier (No.1 Baishui) on Mt. Yulong. Annual and seasonal variations of different climatic signals above the depth of 7 8m are apparent and five\|year snow accumulation can be clearly identified by the seasonal changes of isotopic and ionic composition, some higher values of electrical conductivity and pH values. These annual boundaries can be also verified by the positions of dirty refrozen ice layers at summer surface of each year. The mean annual net accumulation between the balance years of 94/95.and 97/98 are calculated to about 900mm water equivalent. The amplitude of isotopic changes becomes smaller with the increasing depth of the core and isotopic homogenization occurred below the depth of 7 8m. Concentrations of Ca 2+ and Mg 2+ are much higher than those of Na + and K +, reflecting that the air masses for precipitation came far from their marine sources and passed over a longer continental route. Cl - and Na + show well corresponding variation patterns in the firn profile,indicating their same genesis. Concentrations of SO 2- 4 and NO - 3 are low, reflecting very slight pollution caused by human activities in this area. According to the sum of net income recovered from the firn core and the estimated ablation amount, the average annual precipitation above the equilibrium line is estimated in the scope of 225.mm and 3200mm but it needed to be verified by long\|term observation of mass balance. As indicated by the trend of local climatic changes in last 5.years, climatic signals in the firn core and recent observation at the terminal of glacier No.1 Baishui, the glaciers in Mt. Yulong start to advance in 1998 after continuous

关键词： proxy record firn core glacio\|climatic variations Mt. Yul ong, Tibetan Plateau