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

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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.,{2. 2. Institute of Climate and environment, Chinese Academy of Meteoro- logical Sciences, beijing 100081,{2. 3. laboratory of Marine Geology, Tongji University, Shanghai 2.0092.{2. 4. Department of Atmospheric Sciences, Nanjing Institute of Meteorol- ogy, Nanjing 2.0044,{2. 5. Graduate School of the Chinese Academy of Sciences, beijing 10003.,{2. 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

APPLICATION OF SWAT MODEL IN THE UPSTREAM WATERSHED OF THE LUOHE RIVER

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Chinese Geographical Science 2003年第4期13卷 334-339页

作者： ZHANG Xue-song, HAO Fang-hua, CHENG Hong-guang, LI Dao-feng (State key laboratory of Water {2. Simulation,Institute of {2.al Sciences, beijing Normal University,beijing 100875,P. R. china) State key laboratory of Water {2. Simulation Institute of Environmental Sciences Beijing Normal University Beijing 100875 P. R. China

In the Huanghe (Yellow) River basin,soil erosion is a serious problem,while runoff and sediment yield simulation has not been extensively studied on the basis of GIS (Geographic Information System) and distributed hydrological model. GIS-based SWAT (Soil and Water Assessment Tool) model was used to simulate runoff and sediment in the Huanghe River basin. The objective of this paper is to examine the applicability of SWAT model in a large river basin with high sediment runoff modulus,which could reach 770t/(km2.a). A two-stage "Brute Force" optimization procedure was used to calibrate the parameters with the observed monthly flow and sediment data from 1992.to 1997,and with input parameters set during the calibration process without any change the model was validated with 1998-1999’s observed data. Coefficient of examination (R2. and Nash-Suttcliffe simulation efficiency (Ens) were used to evaluate model prediction. The evaluation coefficients for simulated flow and sediment,and observed flow and sediment were all above 0.7,which shows that SWAT model could be a useful tool for water resources and soil conservation planning in the Huanghe River basin.

关键词： luohe river watershed SWAT model sediment flow

Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

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Science china Earth Sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3. MA Haizhou2. LI Zhen4, TAN Hongbing2.& WANG Xianyan1 1. State key {2. of Loess and Quaternary Geology, Institute of Earth environment, Chinese Academy of Sciences, Xi’an 710075{3. 2. Qinghai Institute of Salt Lakes, Chinese Academy of Sciences. Xining 810008,{3. 3. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 10002.,{3. 4. Department of Geography, Qinghai Normal University, Xining 810008,{3. Chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China Chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (103. samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3. T2. T1 were formed at 14, 11.3. 1.55, 1.2. 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3. 1.2.and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12.million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 43. m during the past 1.2.million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

Temporal variations of δ^(18)O of atmospheric water vapor at Delingha

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Science china Earth Sciences 2008年第7期51卷 966-975页

作者： YIN ChangLiang1, YAO TanDong2. TIAN LiDe2. LIU DongNian3. YU WuSheng2.& QU DongMei2.1 State key {2. of Cryoshperic Science, Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 73.000,{3. 2.{2. of environment and Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085,{3. 3.Meteorological Observatory of Haixi Prefecture of Qinghai Province, Delingha 817000,{3. 1. State key laboratory of Cryoshperic Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. laboratory of environment and Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 3. Meteorological Observatory of Haixi Prefecture of Qinghai Province Delingha 817000 China

Oxygen stable isotope of atmospheric water vapor is widely used to study the modern process of cli- mate. Atmospheric water vapor samples were collected at Dlingha, northeast of Tibetan Plateau during the period from July 2.05 to February 2.06. The variation of δ18O and the relationships between δ18O and both the temperature and specific humidity are analyzed in this paper. Results show that the sea- sonal variation of δ18O of atmospheric water vapor at Delingha is remarkable with higher δ18O in summer and lower δ18O in winter. The temporal variation of vapor δ18O shows obvious fluctuations, with magnitude of over 3.‰. The daily variation of the δ18O is highly correlated with air temperature. The relationship between δ18O and atmospheric water vapor content is complex. Study shows that δ18O of atmospheric water vapor is positively correlated with specific humidity in winter in seasonal scale and inversely correlated with specific humidity in summer rainy period. The δ18O values of at- mospheric water vapor are lower than those of precipitation at Delingha, and the average difference is 10.7‰. Variations of δ18O of atmospheric water vapor is also found to be affected by precipitation events, The model results show that the precipitation effect could have caused the vapor δ18O in the raining season to lower by 7% in average in July and August.

关键词： Delingha δ18O atmospheric water vapor

Investigation of effects of clay content on F-Ф relationship by Lattice gas automation using digital rock model

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Petroleum Science 2011年第2期8卷 170-176页

作者： Yue Wenzheng Tao GUo Chai Xiyuan Jiang Hongxiu Mu Hongwu State key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China key laboratory of Earth Prospecting and Information Technology China University of Petroleum Beijing 102249 China CNPC key laboratory of Well Logging China University of Petroleum B eijing 102249 China Bohai Drilling Engineering Company LTD Logging Company Tianjin 300280 China

The Lattice Gas Automation （LGA） method, which is improved by introducing a reflection coefficient for the border between phases to show its effect on current path, is used in this paper to simulate the current flow in digital rock for investigating the effects of clay content and clay distribution types on the relationship between formation factor（F） and rock porosity（φ）. The digital rock model is constructed by simulating a natural deposit of matrix particles with different shapes and radius. Based on the simulation results, it was found that both dispersed clay and laminated clay can lead to a non-Archie relationship of F-φ. The non-Archie effect of laminated clay on the F-φ relationship was more significant than that of dispersed clay. Moreover, a realistic model is developed in this work for quantitatively describing the effect of clay content （Denoted as Vsh） on parameters a and m. These study results have further demonstrated the validity of LGA in study of electrical transport properties at a pore scale.

关键词： Formation factor non-Archie Lattice gas automation porosity clay content claydistribution

Modification of LiCo_(1/3.Ni_(1/3.Mn_(1/3.O_2.cathode material by CeO_2.coating

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Science china(Technological Sciences) 2009年第9期52卷 2737-2741页

作者： WANG Meng,WU Feng,SU YueFeng & CHEN Shi beijing key {2. of {3.,School of Chemical Engineering and {3.,beijing Institute of Technology National Development Center of High Technology Green Materials,beijing 100081,china beijing key {2. of {3. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing China National Development Center of High Technology Green Materials Beijing 100081 China

LiCo1/3.i1/3.n1/3.2.was coated by a layer of 1.0 wt% CeO2.via sol-gel method. The bared and coated LiMn1/3.o1/3.i1/3.2.was characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),cyclic voltammogram (CV) and galvanotactic charge-discharge test. The results show that the coating layer has no effect on the crystal structure,only coating on the surface; the 1.0 wt% CeO2.coated LiCo1/3.i1/3.n1/3.2.exhibits better discharge capacity and cycling performance than the bared LiCo1/3.i1/3.n1/3.2. The discharge capacity of 1.0 wt% CeO2.coated cathode is 182.5 mAh.g-1 at a current density of 2. mA.g-1,in contrast to 165.8 mAh.g-1of the bared sample. The discharge capacity retention of 1.0 wt% CeO2.coated sample after 12.cycles reaches 93.2.,in comparison with 86.6% of the bared sample. CV results show that the CeO2.coating could suppress phase transitions and prevent the surface of cathode material from direct contact with the electrolyte,thus enhance the electro-chemical performance of the coated material.

关键词： LiCo1/3.i1/3.n1/3.2 CeO2 coating Lithium-ion battery

Inter-comparisons of thermodynamic sea-ice modeling results using various parameterizations of radiative flux

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Acta Oceanologica Sinica 2006年第1期25卷 21-31页

作者： ZHANG Zhanhai CHENG Bin LAUNIAINEN Jouko WU Huiding LIU Yu State Oceanic Administration key laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China Finnish Institute of Marine Research Helsinki Fin-00931 Finland National Marine environment Forecast Center Beijing 100081 China

Radiative fluxes are of primary importance in the energy and mass balance of the sea-ice cover. Various parameterizations of the radiative fluxes are studied in a thermodynamic sea-ice model. Model outputs of the surface radiative and heat fluxes and mass balance are compared with observations. The contribution of short-wave radiation is limited to a long part of winter. Therefore, simple schemes are often sufficient. Errors in estimations of the short-wave radiation are due mainly to cloud effects and occasionally to multi-reflection between surface and ice crystals in the air. The long-wave radiation plays an important role in the ice surface heat and mass balance during most part of a winter. The effect of clouds on the accuracy of the simple radiative schemes is critical, which needs further attention. In general, the accuracy of an ice model depends on that of the radiative fluxes.

关键词： parameterizations of radiative fluxes energy balance at the surface of ice/snow thermodynamic sea-ice model Baltic Sea Bohai Sea

Capability description and discovery of Internetware entity

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Science china(Information Sciences) 2010年第4期53卷 685-703页

作者： WANG PuWei1*, JIN Zhi2.3. & LIU HongYan4 1key {2. of Data Engineering and Knowledge Engineering of the Ministry of Education, Renmin University of china, {3. 100872. china 2.1} {2. of High Confidence Software Technologies of the Ministry of Education, Peking University, {3. 100871, china 3.cademy of Mathematics and System Sciences, Chinese Academy of Sciences, {3. 100190, china 4Department of Management Science and Engineering, Tsinghua University, {3. 100084, china 1. key laboratory of Data Engineering and Knowledge Engineering of the Ministry of Education Renmin University of China Beijing 100872 China2. Key Laboratory of High Confidence Software Technologies of the Ministry of Education Peking University Beijing 100871 China3. Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100190 China4. Department of Management Science and Engineering Tsinghua University Beijing 100084 China

Internetware can be formed through aggregation of Internetware entities bottom-up to satisfy the user's requirements. In the process, capability description of Internetware entity plays an important role. This paper proposes a capability description of Internetware entity based on environment ontology. The environment ontology includes environment entities and possible interactions with the environment entities in a particular domain. Tree-like hierarchical state machines are also included in the ontology to describe domain life-cycle of the environment entities. On the basis of the ideas, the capability of Internetware entity is embodied by interacting with environment entities and the changes of the environment entities during the interactions. Finally, this paper describes the matchmaking between capability descriptions of Internetware entities to support the discovery of Internetware entity. An example of online education course is given to illustrate the ideas.

关键词： Internetware capability description domain environment ontology tree-like hierarchical state machine

Validation of three infiltration models on purple soil under simulated rainfall

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Progress in Natural Science:Materials International 2007年第9期17卷 1059-1066页

作者： Wang Yukuan1,2.Fu Bin1,3.Xu Pei1,2.Wang Daojie1,2.Wang Xiantuo1,3.and Wang Yongqiang1,3.1.key laboratory of Mountain Surface Process and Hazards,Chinese Academy of Seiences,Chengdu 610041,china 2.Institute of Mountain Hazards and {3.,Chinese Academy of Sciences,Chengdu 610041,china 3.Graduate University of the Chinese Academy of Sciences,beijing 100049,china) key laboratory of Mountain Surface Process and Hazards Chinese Academy of Seiences Chengdu 610041 China Institute of Mountain Hazards and environment， Chinese Academy of Sciences， Chengdu 610041 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

So as to find models suitable for the prediction of water infiltration in purple soil,infiltration rates simulated by three popular empirical infiltration models,Horton model,Kostiakov model,and the modified Kostiakov model,were compared by using those observed results on slope in purple soil under rainfall simulation.2. sets of infiltration data were divided into two parts for parameter estimation and validation *** performance of the three infiltration models was evaluated with the Nash and Sutcliffe efficiency *** results show that the percent for Nash and Sutcliffe efficiency greater than 0.7 is about 69.7% for the Horton model,and 48.48%,and 54.55% for the Kostiakov model and the modified Kostiakov model,*** model is better than Kostiakov model and the modified Kostiakov model in most rain events in the ***,Kostiakov model is still suitable for reasonable prediction of the infiltration in purple soil sloping farmland because fewer parameters are ***,rainfall intensity has significant effects on the parameter values used in the simulation *** simulation results can be improved by choosing suitable parameters according to the rainfall intensity.

关键词： infiltration model sloping farmland purple soil rainfall simulation