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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 100029, 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 2.004., 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 4.°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

Sorption behavior of U(VI), ^(234.U(VI) and ^(238)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

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Science China Earth sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, LUO Xingzhang3, WANG Ju4. JIN Yuanxin4.& WANG Rucheng1 1. department of Earth sciences, State Key Laboratory of Mineral Deposit Research, nanjing University, nanjing 210093, China 2. Center of Materials Analysis, nanjing University, nanjing 210093, China 3. department of Environmental Science and Engineering, nanjing University, nanjing 210093, China 4. Beijing Geology institute, Nuclear Industry, Beijing 100029, China department of Earth sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis nanjing University nanjing China department of Environmental Science and Engineering nanjing University nanjing China Beijing Geology institute Nuclear Industry Beijing China

The first results of sorption experiments of U(VI), 234.(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, China are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in China. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234. onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, China 2. department of Urban and Resources sciences, {4. University, {4. 210093, China 3. department of Earth sciences, {4. University, {4. 210093, China 4. department of Geography, Shaanxi Normal University, Xi’an 710062, China 5. institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, China 6 department of Geography, Qinghai Normal University, Xining 810008, China 7. Graduate School of the Chinese Academy of sciences, Beijing 100039, China 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of sciences Beijing 100039 China 2. department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. department of Earth sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

The effects of different sea surface temperature distributions over the western Pacific on the summer monsoon properties

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Acta Oceanologica Sinica 1993年第4期12卷 535-547页

作者： Qian Yongfu department of atmospheric sciences, nanjing University, nanjing 210008, China Dept. of atmospheric sciences Nanjing Univ. Nanjing 21008 China. China

A modified and improved primitive equation numerical model with p-sigma incorporated vertical coordinates is used to simulate the effects of different sea surface temperature distributions over the western Pacific on the summer monsoon properties. The different sea surface temperature (SST) distributions are automatically generated in the time integrations by using two different SST models, one of which is called the deep ocean model (DOM) and the other the shallow ocean model (SOM). The SST generated by the DOM has the distribution pattern of the initial SST which is similar to the pattern in the cold water years over the western Pacific, while the SST generated by the SOM has the pattern similar to that in the warm water years. The differences between the experimental results by using DOM and SOM are analyzed in detail. The analyses indicate that the most basic and important characteristics of the summer monsoon climate can be simulated successfully in both experiments, that means the climatic properties in the monsoonal climate regions are mainly determined by the seasonal heating, the contrast between the land and the sea, the topography, and the physical properties of the underlying surfaces. However, the differences between the two experiments tell us that the climatic properties in the summer monsoon regions in the cold water year and the warm water year do differ from each other in details. In the warm water year, the thermal contrast between the land and the sea becomes weaker. Over the warm water area, the upward motions are induced and the dynamical conditions favorable for the convective activities are formed, the Somali low-level cross equatorial current is somewhat weakened, while the cross equatorial currents, east of 90°E, are strongly strengthened, the precipitation amount in the tropical regions largely increases, and the precipitation over the coastal regions increases, too. However the precipitation over the southeast China and its coastal area d

关键词： Sea surface temperature anomaly monsoon climate modelling computational models of SST

Numerical study of rapid cyclogenesis over sea

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Acta Oceanologica Sinica 1989年第1期8卷 51-62页

作者： Du Jun and Yu Zhihao department of atmospheric sciences, nanjing University, nanjing, China Dept. of atmospheric sciences Nanjing Univ Nanjing China. China

A five-layer primitive equation model was used in the study of rapid cyclogenesis over sea. The numerical simulations show that'the Tibetan Plateau, large-scale baroclinicity and heat flux from the sea surface are the three important agents to produce cyclonic vorticity along the east coast of China. The diagnostic computation of a 24.h control simulation indicates that the nonlinear vorticity advec-tion, baroclinicity and diabatic heating are also responsible for the development of the extratropical cyclones over seas.

关键词： Numerical study of rapid cyclogenesis over sea over

Numerical simulation of influence of the anomalies of theCentral-eastern Equatorial Pacific SST and Arctic seaice cover in summer on the atmospheric circulation

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Acta Oceanologica Sinica 1992年第3期11卷 401-411页

作者： Yang Xiuqun and Huang Shisong department of atmospheric sciences, nanjing University, nanjing 210008, China

A series of numerical experiments have been conducted with a perpetual July, nine-level general circulation spectral model to determine the effect of variation of the Arctic sea ice cover extent and the joint effect of anomalies of both the Arctic sea ice cover and the Central-eastern Equatorial Pacific sea surface temperature on the summer general circulation. Results show that the two factors,anomalously large extent of the Arctic sea ice cover and anomalously warm sea surface temperature over the Central-eastern Equatorial Pacific Ocean, play substantially the equal role in the effect on the summer general circulation, and either of them can notably induce the atmospheric anomalies. The main dynamical processes determining the effect of the Arctic sea ice and the equatorial SST anomalies are associated with two leading teleconnection patterns, i. e. the Asia North/American and Eurasian patterns observed in atmosphere. The results presented in this paper again prove that the general circulation is fundamentally motivated by the non-uniform heating between the equator and the pole on the rotating earth.

关键词： Numerical simulation of influence of the anomalies of theCentral-eastern Equatorial Pacific SST and Arctic seaice cover in summer on the atmospheric circulation SST

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4. and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, Guiyang 550003, China 2. nanjing institute of Geology and Palaeontology, Chinese Academy of {4., nanjing 210008, China 3. State Key Laboratory of Papaeobiology and Stratigraphy, nanjing institute of Geology and Palaeontology, nanjing 210008, China 4. department of Geological Science, Ohio State University, Columbus, OH 4.210, USA 5. institute of Geochemistry, Chinese Academy of {4., Guiyang 550002, China) College of Resource and Environment of Guizhou University Guiyang 550003 China nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China department of Geological Science Ohio State University Columbus OH 43210 United States institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 1934. are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

A study on dynamical features of air-sea coupling waves in the tropics

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Acta Oceanologica Sinica 1993年第3期12卷 379-393页

作者： Yang Xiuqun and Huang Shisong department of atmospheric sciences, nanjing University, nanjing 210008, China

The dynamical features of air-sea coupling waves and their stabilities in a simple coupled air-sea model in the tropics have been studied with respect to interaction occurring among different types of the free waves in the o-cean and in the atmosphere. It is pointed out that there exist a stable and an unstable air-sea interaction modes in the tropical coupled system , respectively. The propagation of the unstable mode relies greatly on the zonal space scale, i. e. only for wave length ranging from 5 000 km to 10 000 km can the disturbance unstably move slowly eastward. The waves that slowly propagate unstably eastward agree well with the observational facts. Finally,it is also proposed that the interaction between Kelvin wave in one medium and Rossby wave in another medium is a necessary condition for the occurrence of destabilization of the coupled air-sea system in the tropics.

关键词： Air-sea interaction coupling waves features

A Feedback-Based Web Search Engine

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Wuhan University Journal of Natural sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2,3 , XU Bao-wen 2,3,4., ZHOU Xiao-yu 2,3,4.1. department of Computer Science and Engineering, nanjing University of Posts and Telecommunications, nanjing 210003, Jiangsu, China 2. department of Computer Science and Engineering, Southeast University, nanjing 210096, Jiangsu, China 3. Jiangsu institute of Software Quality, nanjing 210096 Jiangsu, China 4. The State Key Laboratory of Software Engineering, Wuhan University, Wuhan 4.0072, Hubei, China department of Computer Science and Engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4.Foundation item: Supported by the National Natural Science Fundation of China (60373066). National Grand Fundamental Research 973 Program of China (2002CB31200). Opening Foundation of State Key Laboratory of Software Engineering in Wuhan University, Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow UniversityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback