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Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2, JIAN Zhimin3 & HE Jinhai4 1. Nansen-Zhu International research center, Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002., china 2. Institute of climate and Environment, chinese academy of Meteoro- logical sciences, beijing 100081, china 3. Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 4. Department of Atmospheric sciences, Nanjing Institute of Meteorol- ogy, Nanjing 210044, china 5. Graduate School of the chinese academy of sciences, beijing 100039, china Nansen-Zhu International research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of the chinese academy of sciences Beijing 100039 China Institute of climate and Environment Chinese Academy of Meteorological Sciences Beijing 100081 China Laboratory of Marine Geology Tongji University Shanghai 200092 China Department of Atmospheric sciences Nanjing Institute of Meteorology Nanjing 210044 China

Using a global atmosphere-ocean coupled model with the present-day and 14 MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14 MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14 MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 40°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

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Biologically effective ultraviolet radiation in beijing area

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Journal of Environmental sciences 1993年第2期5卷 216-223页

作者： Wang Shaobin Su Weihanresearch center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Ozone layer depletion implies the enhancement of solar ultraviolet radiation at the earth's surface. However, aerosol contributes to the scattering of solar radiation and leads to the reduction of UV-B radiation on the ground. In this paper, the model calculation shows that due to effects of atmospheric ozone and aerosol UV-B radiation in beijing in the past decade has decreased with the annual change rate of 0.7%, which is probably approximate to the measured values. The effects of three scenarios for long-term changes in atmospheric ozone and aerosol concentrations on UV-B radiation reaching the ground in are also discussed.

关键词： UV-B biological efftent zone aerosol beijing.

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Features and mechanism for coagulation－flocculation processes of polyaluminum chloride

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Journal of Environmental sciences 1995年第2期7卷 204-211页

作者： Tang Hongxiao Luan Zhaokun(State Key Laboratory of Environrnental Aquatic Chemistry, research center for Eco- Environmental sciences,chinese academy of sciences , beijing100085 , china)

Ｆｅａｔｕｒｅｓａｎｄｍｅｃｈａｎｉｓｍｆｏｒｃｏａｇｕｌａｔｉｏｎ－ｆｌｏｃｃｕｌａｔｉｏｎｐｒｏｃｅｓｓｅｓｏｆｐｏｌｙａｌｕｍｉｎｕｍｃｈｌｏｒｉｄｅＴａｎｇＨｏｎｇｘｉａｏ；ＬｕａｎＺｈａｏｋｕｎ（Ｓｔａｔｅ... 详细信息

Ｆｅａｔｕｒｅｓａｎｄｍｅｃｈａｎｉｓｍｆｏｒｃｏａｇｕｌａｔｉｏｎ－ｆｌｏｃｃｕｌａｔｉｏｎｐｒｏｃｅｓｓｅｓｏｆｐｏｌｙａｌｕｍｉｎｕｍｃｈｌｏｒｉｄｅＴａｎｇＨｏｎｇｘｉａｏ；ＬｕａｎＺｈａｏｋｕｎ（ＳｔａｔｅＫｅｙＬａｂｏｒａｔｏｒｙｏｆＥｎ...

关键词： polyaluminum chloride coagulation - flocculation microelectrophoresis.

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Simulation of freezing and melting of soil on the northeast Tibetan Plateau

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chinese Science Bulletin 2011年第20期56卷 2145-2155页

作者： XIA Kun 1,2,3,LUO Yong 2,4,5 & LI WeiPing 2 1 Institute of Atmospheric Physics,chinese academy of sciences,beijing 10002.,china 2National climate center,china Meteorological Administration,beijing 100081,china 3Graduate University of chinese academy of sciences,beijing 100049,china 4 center for Earth System Science,Tsinghua University,beijing 100084,china 5Key Laboratory of Earth System Numerical Simulation,Ministry of Education,beijing 100084,china Institute of Atmospheric Physics Chinese Academy of Sciences National climate center China Meteorological Administration Graduate University of chinese academy of sciences center for Earth System Science Tsinghua University Key Laboratory of Earth

Using observational data spanning the period from February to December 2009 and recorded at the Suli station in Qinghai Province,the land-surface model CLM3.0 was employed to simulate the freezing and melting of *** results indicate that the simulated soil temperature is higher than the observed soil temperature and the ultimate thawing date is earlier than the observed date during the melting *** the freezing period,the simulated soil temperature is lower than the observed soil temperature and the ultimate freezing of the deep soil is earlier than that ***,the simulation of freezing is better than that of melting,and the simulation of a shallow layer is better than that of a deeper *** the original CLM3.0,it is assumed that frozen soil begins to melt when the soil temperature exceeds 0C,which is inconsistent with *** critical freeze-thaw temperature was calculated according to thermodynamics equations and the freeze-thaw condition was *** this work,the melting rate for frozen soil was reduced using the modified scheme,and the simulated soil temperature was lowered. Meanwhile,the refreezing of soil during the melting season was well simulated and more closely matched ***,it was found that the rates of melting and freezing differ,with the former being slower than the latter,but refreezing during the melting season is rather quick.

关键词：土壤温度冻结期青藏高原东北部模拟融化观测数据热力学方程表面模型

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MICROSTRUCTURE STUDY ON 16.5mol% CeO_2-ZrO_2 BY MEANSOF TRANSMISSION ELECTRON MICROSCOPE

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Acta Metallurgica Sinica(English Letters) 1997年第3期10卷 174-178页

作者： L-F. Li Z. Zhang and Y Y Li(Cryogenic Laboratory chinese academy of sciences, beijing 100080, china)(Institute of Metal research, chinese academy of sciences, Shenyang 110015, china) Cryogenic Lab Chinese Acad of Sciences Beijing China

The microstructure of a fine-grained 16.5mol% CeO2 stabilized tetragonal zirconia polycrystal (Ce-TZP has been investigated by TEM and it is shown that the mi-crostructures of samples fractured at 298, 77 and 4.2 K change significantly. At 298K there is no stress-induced martensite but a few anti-phase boundaries (APBs) in tetragonal (t) parent phase. With a decrease in temperature, monoclinic (m) product or mariensite within retained t-phase appears. The morphologies are characterized as lenticular and block-like at 77 K and as lenticular and butterfly-like at 4.2 K. The relationship between microstructure and mechanical properties is also discassed in this paper.

关键词： microstructure stress-induced martensite mechanical property

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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 Regions Environmental and Engineering research Institute, chinese academy of sciences, Lanzhou 73000, china Institute of Tibetan Plateau research, chinese academy of sciences, beijing 100085, china Key Laboratory of Cryosphere and Environment Cold and And Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 73000 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 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

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Vortex genesis over the Bay of Bengal in spring and its role in the onset of the Asian Summer Monsoon

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Science china Earth sciences 2011年第1期54卷 1-9页

作者： WU GuoXiong1, GUAN Yue1,2, WANG TongMei3, LIU YiMin1, YAN JingHui4 & MAO JiangYu1 1 State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002., china 2Graduate University of chinese academy of sciences, beijing 100049, china 3Department of Atmospheric Science, Sun Yat-Sen University, Guangzhou 510275, china 4National climate center, china Meteorological Administration, beijing 100080, china 1. State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Atmospheric Science Sun Yat-Sen University Guangzhou 510275 China4. National Climate Center China Meteorological Administration Beijing 100080 China

Physical processes associated with onset of the 1998 Asian summer monsoon were examined in detail using multi-source datasets. We demonstrated that strong ocean-atmosphere-land interaction in the northern Indian Ocean and tropical Asian area during spring is a fundamental factor that induces the genesis and development of a monsoon onset vortex over the Bay of Bengal (BOB), with the vortex in turn triggering onset of the Asian summer monsoon. In spring, strong surface sensible heating over India and the Indochina Peninsula is transferred to the atmosphere, forming prominent in situ cyclonic circulation, with anticyclonic circulations over the Arabian Sea and northern BOB where the ocean receives abundant solar radiation. The corresponding surface winds along the North Indian Ocean coastal areas cause the ocean to produce the in situ offshore currents and upwelling, resulting in sea surface temperature (SST) cooling. With precipitation on the Indochina Peninsula increasing from late April to early May, the offshore current disappears in the eastern BOB or develops into an onshore current, leading to SST increasing. A southwest-northeast oriented spring BOB warm pool with SST >31°C forms in a band from the southeastern Arabian Sea to the eastern BOB. In early May, the Somali cross-equatorial flow forms due to the meridional SST gradient between the two hemispheres, and surface sensible heat over the African land surface. The Somali flow overlaps in phase with the anticyclone over the northern Arabian Sea in the course of its inertial fluctuation along the equator. The convergent cold northerlies on the eastern side of the anticyclone cause the westerly in the inertial trough to increase rapidly, so that enhanced sensible heat is released from the sea surface into the atmosphere. The cyclonic vorticity forced by such sensible heating is superimposed on the inertial trough, leading to its further increase in vorticity strength. Since atmospheric inertial motion is destr

关键词： air-sea interaction spring BOB warm pool monsoon onset vortex inertial oscillation Asian summer monsoon onset

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Landscape evolution and precipitation changes in the Badain Jaran Desert during the last 30 000 years

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chinese Science Bulletin 2000年第11期45卷 1042-1047页

作者： YANG XiaopingInstitute of Geology and Geophysics, chinese academy of sciences, beijing 10002., china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

On the basis of field expeditions into different parts of the Badain Jaran Desert, new evidence of landscape evolution and precipitation changes during the last 30 000 years has been found from the geomorphological, sedimentological and geochronological studies of the megadune. Different cemented surfaces of palaeo-dunes have been observed in many localities, which are representatives of relatively moister environment. The chronological data show that four periods of more humid environment occurred in the past 30 000 years. The stabilization of dunes in a large scale and the existence of many palaeo-lakes and lacustrine terraces confirm the periodic fluctuations of climate. It implies that the intensity of westerlies and Eastasian monsoons varied in the region of Alashan, and the periods of higher precipitation took place even in the times close to the last glacial maximum.

关键词： desert palaeo-dune lake global change Badain Jaran.

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An optimization approach to the similarity criteria of flows and its application

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Progress in Natural Science:Materials International 2006年第3期16卷 241-247页

作者： ZHOU Jifu and LI Jiachun (Institute of Mechanics, chinese academy of sciences, beijing 100080, china) [a]Institute of Mechanics Chinese Academy of Science Beijing China

In the present paper, we propose an optimization approach to investigate the similarity criteria of complex flows. With this approach, we may identify the dominant dimensionless variables governing complex flows by numerical sensitivity analysis. Firstly, we define the sensitivity factor and examine its dependence on the dimensionless variables. Then, we apply this approach to study the similarity criteria of porous media flow in a presumed oil reservoir. The similarity principle obtained from the numerical sensitivity analysis is in agreement with the theoretical law, thus demonstrating the feasibility of the proposed optimization approach. Further explanation is given by analyzing the deviation of pressure distribution in a model from its prototype. In addition, we examine the effects of flow parameter variation on the sensitivity factors and find that the dominant dimensionless variables may change from different sets of parameters.

关键词： similarity optimization sensitivity analysis complex flows model.

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Carbon and Oxygen Stable Isotope Values and Microfossils at 41.4-4.5ka BP in Tai Co,Tibet,china,and Their Paleoclimatic Significance

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1036-1050+1052-1056+1051页

作者： ZHENG Mianping~(1,2,*),LIU Junying~(1,3),MA Zhibang~(1,4),WANG Hailei~(1,2) and MA Nina~(1,2) 1 MLR Key Laboratory of Saline Lake Resources and Environment,Institute of Mineral Resources,CAGS, beijing 100037,china 2 research and Development center for Saline Lakes and Epithermal Deposits,chinese academy of Geological sciences,beijing 100037,china 3 Institute of Geology,chinese academy of Geological sciences,beijing 100037,china 4 Key Laboratory of Cenozoic Geology and Environment,chinese academy of sciences,beijing 10002., china MLR Key Laboratory of Saline Lake Resources and Environment Institute of Mineral Resources CAGS Beijing 100037 China research and Development center for Saline Lakes and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Key Laboratory of Cenozoic Geology and Environment Chinese Academy of Sciences Beijing 100029 China *Correspondence: Mianping ZHENG *Correspondence: Corresponding author. E-mail: zhengmp2010@***

Two sedimentary sections were measured at Tai Co(Co means lake in Tibetan) in western Tibet,*** two sections are almost all composed of clay carbonate beds except in their lower parts where there are carbonized plants at>10 cm depths and dark-colored carbonate clay and clay at 50-70 cm depths,yielding abundant gastropods,ostracods,and *** carbon and oxygen stable isotope values of carbonate,ostracods,and charophytes and ecological features of microfossil communities indicate the following climatic change in the area from 41.4 to 4.5 ka BP:at 41.4-26.2 ka BP,the climate was relatively wet;at 26.2-25.5 ka BP,it was slightly warm-dry;at 25.5-22.5 ka BP,it was warm-wet;at 22.5-21.0 ka BP,it was slightly cold-wet;at 20.5-17.5 ka BP,it became cold abruptly and slightly wet,implying the climate of the last glacial maximum;at 17.5-16.0 ka BP,it was slightly cold-dry;at 16.0-11.8 ka BP,it was slightly warm-wet;at 11.8-10.4 ka BP,it was relatively cold-dry, roughly equivalent to the climate of the Younger Dryas,and at 10.4 ka BP,the temperatures began to rise again;at 10.4-9.4 ka BP,it was slightly warm-wet;at 9.4-8.5 ka BP,there occurred short warm-wet oscillations;at 8.5-7.9 ka BP,it was slightly dry-cold,representing a strong temperature-lowering and drying event in the postglacial stage;at 7.8-6.3 ka BP,it was slightly warm-wet;at 6.3-4.5 ka BP,the climate tended to be cold-dry.4.5 ka BP recorded the maximum aridity since the late part of the late Pleistocene.

关键词： sedimentary environment index paleoclimatic changes late Pleistocene-Holocene(41.4-4.5 ka BP) Tai Co Tibet

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