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Modification of solar radiation model over rugged terrain

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Chinese Science Bulletin 1999年第15期44卷 1345-1350页

作者： Xin Li Guodong Cheng Xianzhang Chen Ling Lu Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lanzhou 730000 Peoples R China

The formula for the duration of possible sunshine has been modified. Two geometrical factors, the circumsolar view factor and the isotropic view factor for calculating solar radiation, have been proposed. The ray-tracing method in computer cartography has been applied to simulating the obstruction of terrain over solar radiation. In addition, the shape factor has been introduced to calculate the reflected radiation from surrounding terrain.

关键词： solar radiation duration of possible sunshine clrcumsolar view factor isotropic view factor terrain influence.

Monitoring of frozen soil hydrology in macro-scale in the Qinghai-Xizang Plateau

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Chinese Science Bulletin 2000年第12期45卷 1143-1149页

作者： Yongjian Ding Baisheng Ye Shiying Liu Yongping Shen Shaoling Wang Meixie Yang Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lanzhou 730000 Peoples R China

Monitoring of frozen soil hydrology in macro-scale was performed by Chinese and Japanese scientists from 1997 to 1998. Quality measured data were obtained. Measured data on soil moisture and temperature are preliminarily analyzed. Based on profiles of soil temperature and moisture in individual measured sites, intra-annual freezing and melting process of soil is discussed. Maximum frozen and thawed depths and frozen days in various depths are estimated. The work emphasized the spatial distribution on soil temperature and moisture in macro-scale and the effect of topography on conditions of soil water and heat.

关键词： active layer of frozen soil soil temperature soil moisture monitoring in macro-scale.

Increasing atmospheric pollution revealed by Pb record of a 7000-m ice core

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Chinese Science Bulletin 1999年第14期44卷 1309-1312页

作者： Wenmian Huo Tandong Yao Yuefang Li lanzhou inst glaciol & geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Concentrations of Pb in Dasuopu ice core in the Qinghai-Tibetan Plateau have been directly measured by ICP-MS at pg/g level. The Pb profile shows a very significant increase in modern times due to anthropogenic input, The use of leaded gasoline in the South Asian countries may be a main source of Pb in this region. The input of Pb to the Dasuopu Glacier is mainly supplied by Indian summer monsoon moisture which traverses the pass at the head of the Dasuopu Glacier.

关键词： Pb pollution Dasuopu ice core.

Accumulation in Dasuopu ice core in Qinghai-Tibet Plateau and solar activity

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Chinese Science Bulletin 2000年第11期45卷 1038-1042页

作者： Keqin Duan Ninglian Wang Yuefang Li Weizheng Sun lanzhou inst glaciol & geocryol Ice Core & Cold Reg Res Lab Lanzhou 730000 Peoples R China

The time series of accumulation in recent 300 years correlated well with solar activity in Dasuopu ice core. Results of spectrum analysis on the accumulation time series of the Dasuopu ice core shows that there are some periods that coincide with the periods of solar activity. By comparing the long-time change trend of the accumulation in the Dasuopu ice core with various kinds of indexes of solar activity intensity, a negative correlation is found between the trend and solar activity.

关键词： Dasuopu ice core accumulation solar activity.

Global pollution shown by lead and cadmium contents in precipitation of polar regions and Qinghai-Tibetan Plateau

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Chinese Science Bulletin 2000年第9期45卷 847-853页

作者： Cunde Xiao Dahe Qin Tandong Yao Jiawen Ren Yuefang Li Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

The analysis of the major ions, lead and cadmium has been performed for snow-pit samples collected from the Arctic, the Qinghai-Tibetan Plateau and the Antarctic Ice Sheet. These snow pits were excavated respectively from the snowpack in Canadian Northwest Territory (NWT) and the central Arctic, three glaciers on the Qinghai-Tibetan Plateau and surface snow along the route of the International Trans-Antarctic Expedition (ITAE). The source regions for the lead pollution of central Arctic have been identified by analyzing of stable lead isotopic ratios, meteorological and atmospheric chemistry studies. It shows that the central Arctic is still under intensive lead input, despite the fact that lead content in Greenland Ice Sheet displays a rapid decreasing since the 1970s due to US and some European countries’ campaigns to reduce lead-containing gasoline-additives. This is because there are multiple lead sources for the central Arctic, including the countries that have not performed gasoline-additives

关键词： key regions of cryosphere heavy metals global pollution.

A new type of ice formation zone found in the Himalayas

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Chinese Science Bulletin 1999年第5期44卷 469-474页

作者： Tandong Yao Jianchen Pu Ninlian Wang Lide Tian Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Ice formation was studied on the Dasuopu Glacier located in the Mount Xixabangma (28°23’ N, 85°43’E) in the Himalayas. Snow pits and shallow ice cores are analyzed to reveal ice formation process. The results show that the ice formation process, or in other words, the process of densitification, on the col (7 000 m a.s.l. ) of the Dasuopu Glacier is a stable, slow and gradual process. The snow-ice transformation on the glacier is estimated to be 30—40 m below the surface. The temperature on the Dasuopu Glacier is very low (～ - 14℃ at 10 m) and similar to that in polar type ice cap. We,therefore, speculate that the process of snow-ice transformation is undertaken under snow pressure,and that there is a percolation zone on the Dasuopu Glacier. The high altitude of the col and monsoon snow fall accompnied by heavy cloud and high albedo favorite the percolation zone formation.

关键词： ice formation glacial accumulation Dasuopu Glacier.

Environmental information recorded in shallow ice core of Dasuopu glacier in the Qinghai-Tibetan Plateau

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Chinese Science Bulletin 1998年第22期43卷 1935-1936页

作者： Cuilan Huang Tandong Yao Jianchen Pu Keqin Duan Ninglian Wang Lide Tian Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

A very strong summer monsoon event during 30-40 kaBP in the Qinghai-Xizang (Tibet) Plateau and its relation to precessional cycle

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Chinese Science Bulletin 1999年第20期44卷 1851-1858页

作者： Shi, YF Liu, XD Li, BY Yao, TD Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lanzhou 730000 Peoples R China Chinese Acad Sci Lanzhou Inst Plateau Atmospher Phys Lanzhou 730000 Peoples R China Chinese Acad Sci Inst Geog Beijing 100101 Peoples R China

Guliya ice core records, high lake-level records in the Qinghai-Xizang Plateau and at its north side as well as vegetation succession records indicated that during the period of 30-40 kaBP, namely the later age of the megainterstadial of last glacial period, or the marine oxygen isotope stage 3, the climate of the Qinghai-Xizang Plateau was exceptionally warm and humid, the temperature was 2-4℃ higher than today and the precipitation was 40% to over 100%

关键词： Qinghai-Xizang (Tibet) Plateau very strong summer monsoon precessional cycle 30-40 kaBP.

Different fossil brachiopod skeletal microstructure of different information on carbon and oxygen isotope contents

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Chinese Science Bulletin 1999年第22期44卷 2087-2094页

作者： Xinqing Li Guojiang Wan Ronggui Huang Chinese Acad Sci Inst Geochem State Key Lab Environm Geochem Guiyang 550002 Peoples R China Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Whether there is isotope fractionation caused by metabolism (vital effect) of bra-chiopods in geologic time with their shells’ δ18O and δ13C has been studied intensively in the field of carbonate isotope geochemistry in the last decade. The approach to dealing with the problem is by comparing isotopic compositions between different fossil brachiopods with their secondary shells which usually consist of two kinds of layers: prismatic layer composed of pris-

关键词： fossil brachiopod geochemistry stable isotope Longmenshan.