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中国科学院地质与地球物理研究所2006学术年会

作者： Tao Yu,~(1,2) Weixing Wan,~1 Libo Liu,~1 Xiaoyin Li,~3 XiaoLi Luan,~2 and Wei Tang~2 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing,china 2 national Centre for spaceweather,china meteorological administration,beijing,china 3 Centre for space Science and Applied Research,Chinese Academy of Sciences,beijing,china

With a theoretical model which yields ionospheric electric fields,we study the yearly variation of ionospheric electric fields at middle and low latitudes under the condition of low solar and quiet geomagnetic *** results show the following *** the ionospheric electric fields are calculated individually in the Northern(or Southern) Hemisphere without including the influence of the other hemisphere(uncoupled),the electric field in the Northern(or Southern) Hemisphere varies in an obvious annual pattern;when the electric field is calculated simultaneously in both hemispheres including the influence of the other hemispheres (coupled),the electric field varies in a predominantly semiannual ***,quite good consistency was found between the behaviors of semiannual variation calculated by our theoretical electric field model and an empirical model of Richmond et al.(1980).

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Observations and modeling of the ionospheric behaviors over the east Asia zone during the 22 July 2009 solar eclipse

Observations and modeling of the ionospheric behaviors over ...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Huijun Le,Libo Liu,Feng Ding,Zhipeng Ren,Yiding Chen,Weixing Wan, Baiqi Ning,Guirong Xu,Min Wang,Guozhu Li,Bo Xiong,and Lianhuan Hu 1 beijing national Observatory of space Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing,china. 2 Also at Sate Key Laboratory of space weather,Chinese Academy of Sciences,beijing,china. 3 Institute of Heavy Rain,china meteorological administration, Wuhan,china. 4 Institute of Earthquake Science,china Earthquake administration, beijing,china. 5 Graduate School of the Chinese Academy of Sciences,beijing,china.

[1]The longest total solar eclipse during the 21st century with a maximum duration of 6 min and 39 s occurred in South and East Asia on 22 July *** TEC data from four GPS stations in the total eclipse region(around 30°N) from 105°E to 135°E are used to study the variation in *** profiles of electron density from Formosa3/Cosmic satellites are used to study the height dependence of the electron density *** also modeled the eclipse effects on the ionosphere by an ionospheric *** the observations from F3/C and the modeled results show that there is an overall decrease in the electron density below F2 region,with the largest relative decrease occurring at Fl *** TEC observations show the delay time of the largest TEC decrease at the total eclipse region with regard to the maximum obscuration is less than five minutes and smaller than what is estimated from the time constant of the plasma loss rate at the F2 peak altitude although main contribution to TEC comes from the plasma density in the F2 *** modeling study shows that,due to the large plasma flux from topside ionosphere to F2 layer,the TEC response around 30°N is mainly due to the electron density response at low altitudes(E and Fl region,200 km below) where the time delay of electron density response is very short(less than 4 min).Thus the time delay of TEC response would also be short as observed by GPS TEC.

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Analyzing Precipitation Characters of South and North china Based on the Exponent of Scaling Law

Analyzing Precipitation Characters of South and North China ...

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中国数学力学物理学高新技术交叉研究会第11届学术研讨会

作者： Gong Zhi-qiang~1 Feng Guo-lin~2 Zhi Rong~2 Zhang Da-quan~2 1.Department of Physics Yangzhou University,Yangzhou 225009,china 2.Laboratory for Climate Studies,national Climate center,china meteorological administration,beijing 100081,china

＜正＞In light of the recent research achievements of nonlinear science and in the context of the daily precipitation data from 1956 to 2000 at 20 stations in south and north china compiled by the national Climate center,we calculated the exponents of power-law tail（EPT）on the cumulative distribution of probability of finding segment with lengths larger than l for each station’s precipitation time series based on BG algorithm, try to analyze the characters of precipitation both in south and north china from a new *** results show that power-law decay（scaling law）of the distribution of the stationary period may be a common occurrence for precipitation and other nonstationary time series;The distribution of EPT for precipitation might be different from area to area,and north china（NC）is comparing lager than south china（SC）;Meanwhile,The exponents of power-law tail（EPTs）might be another effective way to study the abrupt changes contained in nonlinear and nonstationary time series.

关键词： precipitation the exponent of power-law tail abrupt precipitation change grade

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Three Dimensional Shape of the Magnetopause: Global MHD Results

Three Dimensional Shape of the Magnetopause: Global MHD Resu...

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第28届中国气象学会年会

作者： J. Y. Lu 1 , Z. –Q. Liu 2 , K. Kabin 3 1 national center for space weather, beijing, 100081 2 Chinese Academy of meteorological Science, beijing, 100081 3 Royal Military College of Canada, Kingston, Ontario, K7K 7B4

The numerical results from a physics-based global magnetohydrodynamic （MHD） model are used to examine the relationship between the shape and size of the magnetopause and the solar wind conditions. The magnetopause location is identified by tracing three-dimensional streamlines through the simulation domain and is fitted by simple analytical functions. The resulting model is applicable for approximating magnetopause location for dipole tilt angle ~ 0 and interplanetary magnetic field （IMF） Bx and By = 0 nT at both low and high magnetospheric latitudes. In both regions the results are compared with available empirical models. It is shown that IMF Bz mainly affects the flaring angle （the magnetopause shape） and has smaller effects on the magnetopause size. In contrast, the solar wind Dp mainly affects the magnetopause standoff distance （magnetopause size） and has little effect on the magnetopause shape. Both conclusions are consistent with empirical models.

关键词： MHD, solar wind/magnetosphere interaction, magnetopause

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Research on temperature channel calibration of data-acquisition unit of automatic weather station

Research on temperature channel calibration of data-acquisit...

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Measurement Touch the World——IEEE 2011 10th International Conference on Electronic Measurement & Instruments(ICEMI’2011)

作者： Wu Xiangjuan1 2 Lv Wenhua3 Xing Hongyan1 2 Zou Yingquan1 2 1.Jiangsu Technology and Engineering center of meteorological Sensor Network Nanjing University of Information Science and Technology Nanjing 210044 china 2.Jiangsu Key Laboratory of meteorological Observation and Information Processing Nanjing University of Information Science and Technology Nanjing 210044 china 3.meteorological Observation center china meteorological administration beijing 100081 china

A method of utilizing active resistance network to calibrate the temperature channel of data-acquisition unit is proposed in this *** method changes gate-source voltage by micro-controller so as to simulate the *** resistance value measured by data-acquisition unit with the simulated resistances to calibrate the performance of the data-acquisition *** DT50 data-acquisition unit in CAWS600 AWS for an *** software commands,output current and A/D sample duration time of the data-acquisition unit temperature channel are changed to resolve the problem of parameters mismatch,then this data-acquisition unit is calibrated *** experiment result shows this approach provide a reliable means to calibrate AWS data-acquisition unit.

关键词： active resistance network temperature AWS data-acquisition unit calibration

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The definition of effective emissivity of land surface at the scale of remote sensing pixels

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Chinese Science Bulletin 1999年第23期44卷 2154-2158页

作者： LI Xiaowen and WANG Jindi Research center for Remote Sensing and GIS, beijing Normal Unirersity, Keying 100875, china center for Remote Sensing, Boston Univ. , MA02215, USA Research center for Remote Sensing and CIS Beijing Normal University Beijing China center for Remote Sensing Boston Univ. USA

Remote sensing (RS) of land surface temperature (LST) is a very challenging problem at the present development stage of RS science. Tremendous efforts have been devoted to atmosphere correction and temperature emissivity separation (TES) of new LST product algorithms. However, the mechanism of directionality of thermal emission from land surface remains unknown, and even worse, there are confusions on the definition of the effective emissivity of land surface at the scale of RS pixels. The mechanism of directionality of thermal emission

关键词： non-isothermal pixel effective emissivity. directionality of thermal emission.

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SYMMETRIC AND ASYMMETRIC MOTIONS IN THE BAROTROPIC FILTERED MODEL ATMOSPHERE

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Acta Meteorologica Sinica 1987年第1期 10-19页

作者：廖洞贤邹晓蕾 national meteorological center State Meteorological Administration

By expressing the stream function in terms of the symmetric and the antisymmetric components with re-spect to the equator,the barotropic vorticity equation can be separated into two equations,one describing the behaviours of the atmospheric symmetric motion,and the other those of the atmospheric antisymmetric *** them,for the entire global surface at the equivalent barotropic level,the conservations of severalbasic quantities,such as vorticity,angular momentum *** the symmetric and antisymmetric cases,have *** addition,the energy budget equations and the energy conservation expressions for the two kindsof motion are *** can be seen from them that there are not only the conversion between the zonal meankinetic energy and the disturbed kinetic energy in the atmosphere,but also the conversion between thekinetic energy generated by the symmetric and antisymmetric *** the case of including orography and horizontal diffusion into the vorticity equation,a mechanism of the generation of asymmetric behaviours of the atmosphere is *** results show that the asymmet-ric distribution of orography and that of horizontal diffusion coefficients are likely the causes leading to theasymmetric ***,a theoretical comparison between the global model and the hemispheric one fromthe physical point of view is made.

关键词： SYMMETRIC AND ASYMMETRIC MOTIONS IN THE BAROTROPIC FILTERED MODEL ATMOSPHERE

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NUMERICAL SIMULATION OF THE ATMOSPHERIC MIXED LAYER

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Acta Meteorologica Sinica 1987年第1期 78-88页

作者：吴辉碇董彩云 national Research center for Marine Environmental Forecasts State Oceanic Administration Academy of meteorological Science State Meteorological Administration

In this paper,mixed layer height and certain mean elements are predicted by using a dry mixed layer *** variation with time and some basic properties are *** model is tested with the 1967 Australian Wangara experimental *** of the calculated results with the observed data is *** aim of this paper is to build a predictive model describing the basic properties of the mixed layer and attemptsto formulate a boundary layer parameterization scheme suitable for the numerical weather prediction model.

关键词： NUMERICAL SIMULATION OF THE ATMOSPHERIC MIXED LAYER

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On the Prediction of Summer Precipitation in china

On the Prediction of Summer Precipitation in China

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中国气象学会2004年年会

作者： Dong Wenjie Zhang Peiqun Wang Yongguang Sun Leng Ai Wanxiu Zhang Zuqiang Wang Lanning Shi Xueli Li Qingquan Liu Yiming Luo Yong Li Weijing Zhang Guocai Ding Yihui (national Climate center, china meteorological administration, beijing 100081, china)

＜正＞In this paper we interpret the monthly, seasonal and annual climate prediction, especially summer precipitation prediction system developed in national Climate center （NCC）. An Overview of Present Operational Climate Prediction System in NCC is first given. To concentrate on the numerical model’s development and their simulation and prediction , we analysed the Performance of the Nested Climate ModeI（ReGCM-NCC） and Coupled Atmosphere Ocean Mode（CGCM-NCC） in 2003. The results show that CGCM and ReGCM-NCC gave a fairly-well prediction on the summer precipitation, even summer hot-wave of china in 2003. The more encouraging is that the CGCM-NCC gave a fairlywell precipitation in spring in china as well. But we cannot estimate the capability of a method or a model by just one *** the efforts of all NCC members, the prediction system has been established and put into operation. The prediction we issued seems good which can be deduced from the anomaly correlation coefficient between the rainfall forecast and observation. Meanwhile, the dynamical climate models have been developed and updated,and made the routine prediction outputs at both global and regional scales. Prediction experiments have been designed and executed comprehen sive hindcast to identify and validate the models, to improve the methods of forecast analysis, to enhance the model prediction accuracy and model products application capability. Recently, more models have been applied in the routine climate prediction, and the comprehensive climate system model is under study.

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Feasibility study on sub-pixel detection technique applied in 3.5um band on Multi-Channel Scanning Imagery Radiometer of geosychronous orbit meteorological satellite FY-4

Feasibility study on sub-pixel detection technique applied i...

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作者： CHEN Bo-yang~(1,2),WANG Gan-quan~2,GUO Qiang~1,CHEN Gui-lin~2,WEN Xin-rong~2,YU Jian-cheng~(2,3),CHEN Fan-sheng~2 (1,national Satellite meteorological center, Key Laboratory of Radiometric Calibration and Validation for Environmental Satellite, china meteorological administration,beijing 100081,china) (2,Shanghai Institute of Technical Physics,Shanghai 200083,china) (3,Hangzhou Dianzi University,Hangzhou 310018,china)

This article from two factors including the signal to noise ratio(SNR) and image registration accuracy, discussed the situation on 3.5um band on Multi-Channel Scanning Imagery Radiometer of geosychronous orbit meteorological satellite FY-4 used to apply sub-pixel detection technology to enhance image spatial resolution,thereby improve accuracy of fire position and calculation of fire area on the earth surface. According to the 3.5um band on Multi-Channel Scanning Imagery Radiometer of geosychronous orbit meteorological satellite FY-4 needs to detect fog and area with fire on the earth surface at two different characteristics of the target,the 3.5um band has two different pre-amplifier gain settings and different indicators of spatial resolution,the two parameters can be adopted by the atmosphere transmission equation and detectors’ responding to the energy of 3.5um band on Multi-Channel Scanning Imagery *** 3.5um band on Multi-Channel Scanning Imagery Radiometer used to detect areas with fire on the earth surface has a particular target which is area with fire on the earth surface with characteristic of high energy,as a result,using sub-pixel detection technology improves the 3.5um band’s spatial resolution under the stars from 4000m to the nearly 2000m,besides,the signal to noise ratio(SNR) in image after dropping 8～10dB aroused by image reconstruction still meet the system *** shows that as long as the phase error of the original image sequence brought about by instability of the scanning mirror’s speed is less than 10%of the pixel,the effect of phase error to the image reconstruction can be *** the measurement of the scanning mirror’s instantaneous speed on Multi-Channel Scanning Imagery Radiometer,there is a conclusion that the phase error of the original image sequence brought about by the scanning mirror can meet the requirements that the arithmetic of image reconstruction needs to the phase precision. Theoretical analysi

关键词： Multi-Channel Scanning Imagery Radiometer of geosychronous orbit meteorological satellite Area with fire Sub-pixel detection SNR Phase error

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