检索结果-南通市图书馆

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

在线全文

学校读者我要写书评

暂无评论

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 2.0030,china 2.tate Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG),Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 10002.,china 1. Shanghai Typhoon Institute of china meteorological administration Shanghai 200030 China 2. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 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

Deep tectonic setting of the 2.08 Wenchuan M_s8.0 earthquake in southwestern china―Joint analysis of teleseismic P-wave receiver functions and Bouguer gravity anomalies

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2009年第2期52卷 166-179页

作者： LOU Hai1, WANG ChunYong1, L ZhiYong2. YAO ZhiXiang1, DAI ShiGui2.& YOU HuiChuan1 1 Institute of Geophysics, china Earthquake administration, Beijing {2., china 2.Earthquake administration of Sichuan Province, Chengdu 610041, china 1. Institute of Geophysics China Earthquake Administration Beijing 100081 China 2. Earthquake administration of Sichuan Province Chengdu 610041 China

Teleseismic P-wave receiver functions at 2. broadband seismic stations in the Longmenshan fault zone (LMFZ) and its vicinity were extracted, and the crustal thickness and the P- and S-wave velocity ratio were calculated by use of the H-k stacking algorithm. With the results as constraints, the S-wave ve-locity structures beneath each station were determined by the inversion of receiver functions. The crustal structure of the Rear-range zone is similar to that of the Songpan-Garze Block, whereas the velocity structure of the Fore-range zone resembles that of Sichuan Basin, implying that the Central Principal Fault of LMFZ is the boundary between the eastern Tibetan Plateau and the Yangtze Block. Lower velocity zone exists in lower crust of the Songpan-Garze Block and the central-southern seg-ment of the Rear-range zone, which facilitates the detachment of the material in upper and middle crust. Joint analysis of the receiver functions and the Bouguer gravity anomalies supports the thesis on the detachment-thrust mode of the LMFZ. A double-detachment pattern is suggested to the tectonic setting in the Songpan-Garze Block. The upper detachment occurs at the depth of 10-15 km, and represents a high-temperature ductile shear zone. There is a lower detachment at the depth of about 30 km, below which the lower crust flow exists in the eastern Tibetan Plateau. Interpretation of the Bouguer gravity anomalies indicates that the Sichuan Basin is of higher density in upper and middle crust in compari-son with that of the Songpan-Garze Block. The LMFZ with higher density is the result from the thrusting of the Songpan-Garze Block over the Sichuan Basin. In the lower crust, higher P velocity and higher density in the Sichuan Basin are related to more rigid material, while lower S velocity and lower density in the Songpan-Garze Block are related to the softened and weakened material. The higher density block beneath the Sichuan Basin obstructs the eastward flow of lower crustal ma

关键词： Longmenshan fault zone (LMFZ) Wenchuan Ms8.0 earthquake deep tectonic setting teleseismic receiver function

Virtual ChuanDian--A parallel numerical modeling of Sichuan-Yunnan regional strong earthquake activities: Model construction and parallel simulation

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2009年第10期52卷 1585-1598页

作者： ZHANG Huai1, WU ZhongLiang1,2. ZHANG DongNing2. LIU Jie2. WANG Hui2. YAN ZhenZhen1,2.& SHI YaoLin11 Laboratory of Computational Geodynamics, Graduate University of Chinese Academy of Sciences, Beijing 100049, china 2.Institute of Geophysics, Chinese Earthquake administration, Beijing {2., china 1. Laboratory of Computational Geodynamics Graduate University of Chinese Academy of Sciences Beijing 100049 China 2. Institute of Geophysics Chinese Earthquake Administration Beijing 100081 China

Reasonable use of mathematical modeling and numerical simulation of regional earthquake activities has attracted more and more attentions in realistic seismicity studies in recent years. The inherent nature of their attendant multi-scale properties, from either the temporal or the spatial direction, necessitates the use of the cutting-edge massive parallel data processing techniques. Our study here is focused on the model construction and numerical simulation of the regional stress evolution after large earthquake sequences along the fault zones in Sichuan and Yunnan areas, using large-scale parallel finite element approximations with tens of millions of unstructured meshes on the distributed systems. The objective of our study is to provide a state-of-the-art model and a large-scale numerical simulation platform, on which estimation of the risk of large earthquake triggering sequences can be carried out in a middle or long-term time scale with realistic data and constrains inputted from field observation and geological survey.

关键词： Sichuan-Yunan area seismic processing parallel simulation initial stress field

Variations of δ^(18)O in precipitation from the Muztagata Glacier, East Pamirs

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2006年第1期49卷 36-42页

作者： LI Zhen1, YAO Tandong1,2. TIAN Lide1,2. XU Baiqing1,2.& Wu Guangjian2.1. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research Institute and Institute of Tibetan Plateau Research, Chinese Academy of Sciences and Chinese Academy of meteorological Sciences, china meteorological administration, CAS, Lanzhou 730000,{2. 2. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085,{2. 1. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China 2. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

Expeditions to Muztagata (in the eastern Pamirs) during the summer seasons of2.02.and 2.03 collected precipitation samples and measured their oxygen isotopes. The δ^(18)O inprecipitation displays a wide range, varying from -17.40per thousand to +1.33per thousand inJune—September 2.02.and from -2..31per thousand to +4.59per thousand in May—August 2.03. Theδ^(18)O in precipitation correlates with the initial temperature of precipitation during theobserving periods. The positive correlation between δ^(18)O and temperature suggests that δ^(18)Ocan be used as an indicator of temperature in this region. The δ^(18)O values in fresh-snow samplescollected from two snow events at different elevations on the Muztagata Glacier show a strong''altitude effect'', with a ratio of nearly -0.40per thousand per 100 m from 5500 m to 7450 m.

关键词： Muztagata, δ18O, temperature, altitude effect.

Influences of greenhouse effect on agricultural production in china

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 1990年第4期2卷 3-10页

作者： Gao Suhua, Ding Yihui, Pan Yaru and Zhao Zongci Academy of meteorological Science,State meteorological {2.,Beijing 100081,china

An obvious warming in china induced by doubled carbon, dioxide as simulated by the climatic models have been found. It is also noticed that there might be drying or wetting in some parts of china induced by doubled CO2.as simulated by the general circulation models(GCMs). Agricultural productivity mainly depends on the temperature, rainfall and soil moisture in china. The changes of agricultural productivity in the different parts of china induced by doubled CO2.have been estimated in this paper. It is shown that the greenhouse effect might cause increasing production in some parts of china and decreasing production in other parts of china.

关键词： greenhouse effect agricultural productivity doubled CO2 GCMs climatic productivity force.

Energy dispersion of complex non-isolated vortices

在线全文

学校读者我要写书评

暂无评论

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 2.0044, china 2.Wuxi Research {2. of Environmental Science and Technology, Wuxi 2.4031, china Key Laboratory of meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Wuxi Research center of Environmental Science and Technology

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

Interdecadal trend turning of global terrestrial temperature and precipitation during 1951-2.02

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2008年第11期18卷 1383-1393页

作者： Xiaohui Shi Xiangde Xu State Key Laboratory of Severe Weather,Chinese Academy of meteorological Sciences,Beijing 100081,{2. State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

A grid-by-grid counting of interdecadal trend turning(ITT)of annual mean surface air temperature(SAT)and total precipitation at 67,359 terrestrial grids in the period 1951-2.02.is *** analysis of the last ITTs of SAT and total precipitation in the period,in the context of both occurrence time and linear trends after the breakpoint,indicates that a warming trend has become highly significant across most reagent of the world in the late 2.th *** terrestrial grids have recorded an ITT of total precipitation in either the 1970s or 1980s,and 45.7% of the terrestrial grids in the study have seen a decreasing trend in total annual precipitation after the break- point,with the remaining 54.3% having experienced an increasing ***,global terrestrial regions have experienced either an increasingly warm and dry climate or an increasingly warm and wet *** analysis of ITT of regional mean SAT and total pre- cipitation in 2. regions shows that the Northern American continent has become increasingly warm and dry after the last interdecadal ***,the African continent has become increasingly warm and wet,with both Europe and most of Asia having the same *** South America and the West of Australia have experienced an opposite trend in climate,becoming increasingly cold and wet.

关键词： Global terrene Surface air temperature Precipitation Interdecadal trend turning

Wave decomposition phenomenon and spectrum evolution over submerged bars

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2009年第3期28卷 82-92页

作者： LI Benxia YU Xiping national Marine Environmental Forecasting center State Oceanic Administration Beijing 100081China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

Wave decomposition phenomenon and spectrum evolution over submerged bars are investigated by a previously developed numerical model. First, the computed free surface displacements of regular waves at various locations are compared with the available experimental data to confirm the validity of the numerical model, and satisfactory agreements are obtained. In addition, variations of decomposition characteristics with incident wave parameters and the change of energy spectrum for regular waves are also studied. Then the spectrum evolution of irregular waves over submerged bars, as well as the influence of incident peak wave period and the steepness of the front slope of the bar on spectrum evolution, is investigated. Wave decomposition and spectral shape are found to be significantly influenced by the incident wave conditions. When the upslope of the bar becomes 1：2. the length of the slope becomes shorter and will not benefit the generation of high frequency energy, so spectrum evolution is not significant.

关键词： wave decomposition spectrum evolution nonlinear waves irregular waves submerged bars

Detection of the Kuroshio frontal instable processes (KFIP) in the East china Sea using the MODIS images

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2010年第6期29卷 35-43页

作者： JIA Yongjun ZHANG Jie national Satellite Ocean Application Service Beijing 100081 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

The Kuroshio frontal instable processes （KFIP） in the East china Sea （ECS） not only have a great impact on the hydrologic characteristics,the pollutants drift,the distribution of seafloor sediment and the ships navigation of the ECS,but also are closely related to the climate changes of the coastal areas of the *** the frequency and area of occurrence of the KFIP have not been studied fully and *** of its high spatial and temporal resolution,MODIS data is a kind of very good data source for surveying and researching the KFIP in the *** aim of this study is to detect the KFIP in the ECS by using MODIS data,and to study the frequency and region of occurrence of the KFIP in the *** selection has coverage of level 2.data of MODIS SST and Kd490 ranging from July 1,2.02.to June 30,2.09 of the ECS when there was no cloud impact or *** using of the data,the minimum standard of the Kuroshio temperature fronts and the diffuse attenuation coefficient （Kd490） fronts of the ECS are *** on these standards and the curvature distinguish methods,the standard of curvature distinguish for the KFIP in the ECS are put *** making use of this standard,we study a total of 2.73 satellite-derived images,and discover that as long as there is no cloud impact from January to May and October to December,the KFIP in the ECS are surely found in MODIS satellite *** June to September,the frequency of occurrence can also reach to 82.9% at ***,it is obtained that there are three source regions of these instability processes,namely,（2.°N,12..5°E） nearby,（2.°N,12.°E） nearby and （30°N,12.°E） *** differences of the characteristics of these instability processes which are generated in different regions are analyzed in the present study.

关键词： Kuroshio frontal instable processes frequency and region of occurrence East china Sea MODIS