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Respondence and feedback of modern sand deserts to climate change ——A case study in Gurbantunggut Desert

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chinese Science Bulletin 2000年第12期45卷 1137-1142页

作者： WEI WenshouXinjiang institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china Open laboratory of ice-{5., cold and arid regions environmental and engineering research institute, chinese academy of{15., lanzhou 730000, china Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Open laboratory of ice-core Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The research on the respondence and feedback of modern sand deserts to the climate change is an important component part in the studies on the global climate change. Deserts respond to the climate change, meanwhile, they affect the climate with their feedback of peculiar environment during the respondence. Many researches on desert climate have been carried out at home and abroad. However, there is little research on the respondence and feedback of modern fixed, semi-fixed and mobile deserts in arid areas to the climate change, in which the factor analysis as well as the parameter changing effects is especially the difficult problem all along. In this note, the parameters of the respondence and feedback of Gurbantunggut Desert to the climate change are measured and analyzed, some variable parameters of water-heat exchange are obtained, and a numerical model of desertification is developed according to a series of climate change of about 40 years and the variable relations of meteorological and physical

关键词： Gurbantunggut Desert climate change respondence and feedback numerical model.

Decrease trend of dust event frequency over the past 200 years recorded in the Malan ice core from the northern Tibetan Plateau

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chinese Science Bulletin 2005年第24期50卷 2866-2871页

作者： WANG Ninglian key laboratory of Cryosphere and environment, cold and arid {5. environmental and engineering research institute, chinese academy of sciences, lanzhou 73000,{12. institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085.{12. key laboratory of Cryosphere and environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China

By analyses of the dust layers in the Malan ice core from the northern Tibetan Plateau, it was found that dirty ratio in this core might be a good proxy for dust event frequency. The variations in the dirty ratio displayed a de- crease trend over the past 200 years, which implies that dust events became less frequent during the study period. The decrease trend in the variations in dust event frequency might be caused mostly by the natural processes, including increasing precipitation and weakening westerly which might be related with global warming. Furthermore, significant negative correlation was found between the dirty ratio and δ 18O in the Malan ice core. This is highly important for studying the effect of atmospheric dust on climate change.

关键词：青藏高原马伦冰核气候变化扬尘事件发生频率

Variations in air temperature during the last 100 years revealed by δ^(18)O in the Malan ice core from the Tibetan Plateau

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chinese Science Bulletin 2003年第19期48卷 2134-2138页

作者： WANG Ninglian, YAO Tandong, PU Jianchen, ZHANG Yongliang, SUN Weizhen & WANG Youqing key laboratory of ice core and cold {5. environment, cold and arid {5. environmental and engineering {12. institute, chinese{15. of sciences, lanzhou 730000, china key laboratory of ice core and cold {5. environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

By comprehensive analyses, it was found that the variations in d 18O recorded in Malan ice core from theKekexili Region on the Tibetan Plateau could represent thechanges in air temperature during the summer half year (from May to October) over the Kekexili Region and the northern margin of the Tibetan Plateau. The general increase trend in d18O in this ice core during the past century indicated climate warming, and it was estimated that air temperature during the summer half-year rose about 1.2C over there then. However, this ice core record documented that the study area has been cooling while most of the world has been dramatically warming since the late 1970s. A teleconnection was foundbetween the variations in d 18O in the Malan ice core and the North Atlantic Oscillation. Moreover, the variations in d 18O in this ice core were similar to that in the summer half-year air temperature over the southern Tibetan Plateau on thecenturial time scale, but opposite on the multidecadal timescale.

关键词：空气温度 δ^18O 西藏高原全球变暖马伦冰核北大西洋波动气候变化

Water transfer characteristics during methane hydrate formation and dissociation processes inside saturated sand

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Journal of Natural Gas Chemistry 2010年第1期19卷 71-76页

作者： Peng Zhang, Qingbai Wu, Yibin Pu, Guanli Jiang, Jing Zhan, Yingmei Wang State key laboratory, cold and arid regions {5.al and engineering research institute, chinese academy of sciences, lanzhou 730000, Gansu, china State key laboratory Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

Gas hydrates formation and dissociation processes inside porous media are always accompanied by water transfer behavior, which is similar to the water behavior of ice freezing and thawing processes. These processes have been studied by many researchers, but all the studies are so far on the water transfer characteristics outside porous media and the water transfer characteristics inside porous media have been little known. In this study, in order to study the water transfer characteristics inside porous media during methane hydrate formation and dissociation processes, a novel apparatus with three pF-meter sensors which can detect water content changes inside porous media was applied. It was experimentally observed that methane hydrate formation processes were accompanied by water transfer from bottom to top inside porous media, however, the water behavior during hydrate dissociation processes was abnormal, for which more studies are needed to find out the real reason in our future work.

关键词： methane hydrate formation and dissociation processes: water transfer inside porous media saturated

Vicissitude of Sogo Nur and environmental-climatic change during last 15.0 years

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Science china Earth sciences 2004年第Z1期47卷 61-70页

作者： JIN Heling, XIAO Honglang, SUN Liangying, ZHANG Hong, SUN Zhong & LI Xiaozekey laboratory of Desert and Desertification, cold and arid regions {5.al and engineering research institute, chinese academy of sciences, lanzhou 730000, china School of Resources and {5., lanzhou University, lanzhou 730000, china key laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China School of Resources and environment Lanzhou University Lanzhou China

Lakes in arid zone are sensitive to climatic changes. The lacustrine sediment sequence in Sogo Nur has well and truly recorded climatic events such as the Sui-Tang Dynasty Warm Period, the Song-Liao Dynasty cold Period, the Medieval Warm Period, the Little ice Age and the 20th Century Warm Period. Commonly, the climate in warm Periods was relatively humid,accordingly the lake area extended and water level rose, and vice versa. Apart from climatic change, human activity is also an important factor of influencing lake vicissitude, and they played the dominant role alternatively during different periods; the factor of climatic change predominated in historical period, while since the beginning of the 20th century the utilization of water resources by human has became decisive.

关键词： granularity, soluble salt, lake vicissitude, climatic change, Sogo Nur.

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3,5. SUN Junying4,5. Paul A. Mayewski2 & QIN Dahe5.1. National Climate Center, china Meteorological Administration, Beijing 100081, china 2. Climate Change institute, University of Maine, Orono, ME 04469, USA 3. institute of Tibetan Plateau research,{5., Beijing 100085. china 4. chinese academy of Meteorological sciences, Beijing 100081, china 5. key laboratory of ice core and cold regions environment, {12. and arid environmental and {15. research institute,{5., lanzhou 730000, china National Climate Center China Meteorological Administration Beijing China Climate Change institute University of Maine Orono ME USA institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China key laboratory of ice core and cold {5. environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China chinese academy of Meteorological sciences Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) icelandic Low. A deepening of the icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science china Earth sciences 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2, AN Lizhe1, 3, WU Guangjian2, XU Baiqing2, MA Xiaojun 3, LI Zhen1, WANG Junxia1 & YU Wusheng1 1. key laboratory of ice core and cold {5. environment, cold and arid {5. environmental and engineering {12. institute, chinese academy of sciences,{15., china 2. institute of Tibetan Plateau {12., chinese academy of sciences, Beijing 100085. china 3. College of Life Science, lanzhou University,{15., china chinese academy of sciences lanzhou University

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium

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Science china Earth sciences 2005年第4期48卷 521-529页

作者： LIU Xiaohong1,2, QIN Dahe1, SHAO Xuemei , CHEN Tuo1 & REN Jiawen12.1. cold and arid regions environmental and {5. research institute, chinese academy of sciences, lanzhou 730000, china 2. institute of Geographical sciences and Natural Resources research, chinese academy of sciences, Beijing 100101, china cold and arid regions environmental and engineering {5. institute Chinese Academy of Sciences Lanzhou China institute of Geographical sciences and Natural Resources research Chinese Academy of Sciences Beijing China

Based on the cross-dated tree-ring samples collected from the middle Qilian Moun- tain, a standard ring-width chronology had been developed, which covered the period AD 1000 to 2000. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the “Little ice Age” and the con- tinuous warming during the twentieth century. Comparison between the ring-width chronology and δ18O records from the Dunde ice core in the Qilian Mountain indicated that there was a con- sistent trend in both time series. A significant correlation existed between our ring-width chro- nology and the Northern Hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global cli- mate.

关键词： middle Qilian Mountain, tree-ring width chronology, temperature variations.

Climatic and environmental changes over the last millennium recorded in the Malan ice core from the northern Tibetan Plateau

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Science china Earth sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1,2, YAO Tandong2,1, PU Jianchen1, ZHANG Yongliang1 & SUN Weizhen1 1. key laboratory of Cryosphere and environment, cold and arid {5. environmental and engineering research institute, chinese academy of sciences, lanzhou 730000,{12. 2. institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085.{12. key laboratory of Cryosphere and environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China

In this paper, climatic and environmental changes were reconstructed since 112.A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 18O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 20th-century warming was within the range of natural climate variability, and the warmest century was the 17th century while the warmest decade was the 1610s, over the entire study period. The “Medieval Warm Epoch” and “Little ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 19th century. Comparing the variations of δ 18O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 101―102 years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the {12. and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.