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Progress and review of the studies on the end-Triassic mass extinction event

Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2, LU Yuanzheng1,2,3.& XU Daoyi4 1. Research Institute of Petroleum Exploration and Development, Beijing 100083. china 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, Beijing 100083. china 3. china University of Geosciences, Beijing 100083. china 4. Institute of Geology, china Earthquake administration, Beijing 100029, china Research Institute of Petroleum Exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of Petrochina Beijing China china University of Geosciences Beijing China Institute of Geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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Energy dispersion of complex non-isolated vortices

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Chinese Science Bulletin 2011年第25期56卷 2713-2717页

作者： LUO ZheXian 1,2 1 Key Laboratory of meteorological Disaster of Ministry of Education, Nanjing University of Information Science and Technology, Nanjing 210044, china 2 Wuxi Research center of Environmental Science and Technology, Wuxi 21403., china Key Laboratory of meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Nanjing China Wuxi Research center of Environmental Science and Technology Wuxi China

Energy dispersion is a fundamental scientific problem in the study of natural disasters such as typhoons, heavy rain and earthquakes. The problem has been addressed by both multi-discipline research and forecast studies. The dynamics of isolated circular vortex energy dispersion have been solved. However, the disastrous results of typhoons and heavy rain often occur due to non-isolated circular vortices, the dynamics of which are explored in this paper. The energy dispersion characteristics of non-isolated vortices with complex structural patterns are examined using a linearized nondivergent barotropical vorticity equation model. In the initial field, a tropical cyclone (TC) vortex and a meso-scale vortex coexist, forming a complex structural pattern. An analytic solution based on a Fourier transform and simulations using a two-dimensional model show the following. (1) A wave train of TC-G-D may be created by the energy dispersion where the line connecting the three member centers of the wave train is parallel to the x axis in the case of an initial TC vortex without a meso-scale vortex. (2) A wave train of TC-G-D may also be created by energy dispersion. However, the line connecting the three member centers of the wave train would no longer be parallel to the x axis. Instead, they would form a triangle in the presence of the initial TC vortex with the meso-scale vortex. (3. There is a nonlinear relationship between the initial intensity of the meso-scale vortex and the base angle of the triangle. These results have the potential to be applied in the field of typhoon forecasting.

关键词：能量色散非隔离式旋涡非线性关系中尺度涡台风预报结构模式傅立叶变换

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研究者发起的老年医学临床研究管理专家共识

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中华老年医学杂志 2024年第6期43卷 657-661页

作者：于玲玲张鹏俊国家老年医学中心北京医院科研处国家老年医学中心中国医学科学院老年医学研究院北京100730 不详

研究者发起的老年医学临床研究具有临床需求迫切、研究参与者情况复杂、研究风险大等特点,需要通过加强管理来提高研究质量。本共识对研究者发起的老年医学临床研究的定义、组织管理、立项管理、过程管理、结题管理等方面给出推荐意见,... 详细信息

研究者发起的老年医学临床研究具有临床需求迫切、研究参与者情况复杂、研究风险大等特点,需要通过加强管理来提高研究质量。本共识对研究者发起的老年医学临床研究的定义、组织管理、立项管理、过程管理、结题管理等方面给出推荐意见,为医疗卫生机构开展研究管理工作提供参考。

关键词：生物医学研究研究者-受试对象关系研究管理

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An integrative estimation model of summer rainfall-band patterns in china

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Progress in Natural Science:Materials International 2007年第3期17卷 280-288页

作者： WEI Fengying (State Key Laboratory of Severe Weather, Chinese Academy of meteorological Sciences, Beijing 100081, china) State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

Three variation indices are defined to objectively and quantitatively represent fluctuations of three rainfall-band patterns in summers in china for the period from 1951 to 2005, and the variation features of these indices are analyzed on both of interdecadal and interannual scales. A new method is proposed to establish an integrative estimation model based on the analysis of rainfall-band indices, and the model is applied to air, ocean factors to estimate their roles on variations of three rainfall-band patterns on different time-scales. The tests of estimation effects show that the fluctuations of three rainfall-band patterns are composed of variations on both significant inter-decadal and interannual scales, of which the interannual variation is mainly influenced by the Elnino/Lanina events, the East Asia monsoon and the ridge locations of subtropical high pressures in western pacific, while the interdecadal variation is mainly controlled by the Pacific decadal oscillation and interdecadal oscillations of the Arctic oscillation, ENSO, Nino3.sea surface temperature and summer monsoon. The estimated results from the integrative estimation model of rainfall-band patterns suggest that the way of estimation first according to each time scale of both the interdecadal and interannual scales, then estimating with an integration, which is proposed in this paper, has an obvious improvement on that without separation of time scales.

关键词： rainfall-band pattern interannual variation interdecadal variation integration estimation model.

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Eleventh Five-Year Plan for Space Science Development

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空间科学学报 2008年第5期28卷 499-505页

作者： china national Space administration china national Space administration

Preface Space science is a discipline to study the universe,to investigate the fundamental process of molecules and atoms,and reveal,at the underlying roots,the laws of the external world.

关键词：第十一个五年计划空间科学空间计划研究进展

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Influence of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific on the inter-decadal variations of the stratosphere-troposphere exchange of water vapor

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Science china Earth Sciences 2008年第8期51卷 1179-1193页

作者： ZHAN RuiFen1,2&LI JianPing2 1Shanghai Typhoon Institute of china meteorological administration,Shanghai 20003.,china 2State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG),Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,china Shanghai Typhoon Institute of china meteorological administration Shanghai China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific(WNP) on them by using the Wei method with reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) for the years of *** climatology shows that the upward transport of water vapor across the tropopause in boreal summer is the most robust over the joining area of the South Asian Peninsula and Indian-Pacific Oceans(defined as AIPO).The upward transport over there can persistently convey the abundant water vapor into the stratosphere and then influence the distribution and variation of the stratospheric water *** analysis shows that interdecadal variations of the water vapor exchange over the AIPO are significant,and its abrupt change occurred in the mid-1970s and the early *** these three periods,as important channels of the water vapor exchange,the effect of Bay of Bengal-East Asia as well as South china Sea was gradually weakening,while the role of the WNP becomes more and more *** studies show that atmospheric heat sources over the Tibetan Plateau and the WNP are two main factors in determining the interdecadal variations of water vapor *** thermal influences over the Tibetan Plateau and the WNP have been greatly adjusted over the pass 44 *** synthesis influences the interdecadal variations of the water vapor exchange by changing the Asian summer monsoon,but their roles vary with time and *** after 1992,the influence of heat source over the Tibetan Plateau remarkably weakens,while the heat source over the WNP dominates the across-tropopause water vapor *** have important implications for understanding the transport of other components in the atmosphere and estimating the impact of human activities(

关键词： Tibetan Plateau tropical western North Pacific atmospheric heat source STE inter-decadal variations

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Applied research of landscape ecology in desertification monitoring and assessment

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Journal of Environmental Sciences 2000年第3期12卷 349-354页

作者： LI Feng, SUN Si heng (Academy of Forest Inventory and Planning/china national Desertification Monitoring center, State Forestry {3., Beijing 100714, china) Academy of Forest Inventory and Planning/china national Dese 北京 1 0 0 71 4

A preliminary research on landscape ecology in desertification monitoring and assessment was reported. Also, this paper laid stress on the study of landscape diversity, dominance, evenness and Markov Matrix model and their respective landscape ecological meanings in the desertification monitoring and assessment. Concurrently, it took Shazhuyu Experimental Area, Qinghai Province as a specific case study.

关键词： landscape ecology desertification monitoring and assessment Shazhuyu Experimental Area

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Interannual variation of annual precipitation and urban effect on precipitation in the Beijing region

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Progress in Natural Science:Materials International 2007年第9期17卷 1042-1050页

作者： Yu Shuqiu(State Key Laboratory on Severe Weather,Chinese Academy of meteorological Sciences,Beijing 100081,china) State Key Laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

The large scale character of the interannual variation of precipitation and the urban effect on local annual precipitation anomaly are investigated in this paper based on the 1960-2000 annual precipitation observations at 20 stations in the Beijing *** results show that:the annual precipitation in the Beijing region possesses the large scale variation character with the linear trend of-1.197/10 yr,which corresponds to a total reduction of 27.82 mm in annual precipitation in the 41 years;the local annual precipitation anomalies(percent of the normal 1960-2000)show a positive center near the urban area,*** precipitation island(UPI),whose intensity increases with the linear trend of 0.6621%/10 yr,opposite to the interannual trend of large scale precipitation over the Beijing region;changes in the UPI are also associated with the intensity of synoptic processes of precipitation,and when the synoptic processes are strong(wet years),the intensity of UPI strengthens,while the synoptic processes are weak(dry years),and the UPI disappears in the Beijing region.

关键词： urban precipitation island effect interannual climate variation precipitation Beijing atmospheric science

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meteorological observations on Mount Everest in 2005

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Progress in Natural Science:Materials International 2007年第7期17卷 828-837页

作者： Xie Aihong~(1**) Qin Dahe~1 Ren Jiawen~1 Qin Xiang~1 Xiao Cunde~(1,2) Hou Shugui~1 Kang Shichang~(1,3. Yang Xingguo~(1,4) Jiang Youyan~1 (1.Key Laboratory of Cryosphere and Environment,Cold and Arid Regions Environment and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 73.000,china 2.Chinese Academy of meteorological Science,Beijing 100081,china 3.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100085,china 4.Gansu Provincial meteorological Bureau,Lanzhou 73.000,china) Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Chinese Academy of meteorological Science Beijing 100081 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Gansu Provincial meteorological Bureau Lanzhou 730000 China

Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its *** April 2005,an automatic weather station was installed at the mountain's North Col(6523.m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 22,*** monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.928,0.877,0.682,0.755,0.826 and 0.676(n=83.p3.0.485 and 0.487(n=83.pmeteorological *** conclusions are much important for research on meteorology and climate changes in the region.

关键词： Mount Everest meteorological observation Dingri County radiation air temperature relative humidity air pressure wind

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Case studies on mesoscale structures of heavy rainfall system in the Yangtze River generated by Meiyu front

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Science china Earth Sciences 2005年第8期48卷 1303-1311页

作者： LIU Liping1, RUAN Zheng1 & QIN Danyu2 1. Chinese Academy of meteorological Sciences, Beijing 100081, china 2. Nanjing Institute of Meteorology, Nanjing 210044, china Chinese Academy of meteorological Sciences Beijing China Nanjing Institute of Meteorology Nanjing China

A heavy rainfall system was observed over the Yangtze River during Meiyu season by using dual-Doppler radar systems in the field experiment conducted by the project of national Fundamental Research Planning “Research on formation mechanism and the prediction theory of hazardous weather over china”. The three-dimensional mesoscale kinematic structure and process of a heavy rain on 22 and 23.July, 2002 are investigated by using the radial velocity and dual-Doppler radar technique. The results show that a southwest-northeast oriented rain band with the length of about 1000 km involves numbers of meso-β or meso-γ-scale convective cells with the size of 20―50 km. The heavy rain band in the middle reaches of the Yangtze River ex-ists in a low-level wind shear. The interaction between southwest low-level jet on the southern side of wind shear and east wind on the northern side formed the updraft. The wind disturbance, wind shear and convergence generate the convective action. The new cell developed in right rear flank of rain band and moved to the southwest wind area, where the vapor is abundant. This kind of echo can last a long time and developed well. The strong convective echoes are often ac-companied by the meso-γ-scale vortex and convergence.

关键词： heavy rainfall in Meiyu front, mesoscale structure, dual-Doppler radar, middle reaches of the Yangtze River, low-level jet.

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