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中国北方主要沙漠沙尘粒度特征比较研究

水土保持研究 2011年第6期18卷 6-11页

作者：霍文何清杨兴华刘新春丁国锋程玉景中国气象局乌鲁木齐沙漠气象研究所乌鲁木齐830002 和静县巴音布鲁克气象站新疆巴音布鲁克841314 库尔勒市气象局新疆库尔勒841000

粒度分析在区分沉积环境、判定物质输运方式、判别水动力条件和分析粒径趋势等方面具有重要作用。对塔克拉玛干沙漠、库姆塔格沙漠、巴丹吉林沙漠、腾格里沙漠、毛乌素沙地沙尘粒度参数进行了分析比较研究。结果表明:风沙天气过程中,塔... 详细信息

粒度分析在区分沉积环境、判定物质输运方式、判别水动力条件和分析粒径趋势等方面具有重要作用。对塔克拉玛干沙漠、库姆塔格沙漠、巴丹吉林沙漠、腾格里沙漠、毛乌素沙地沙尘粒度参数进行了分析比较研究。结果表明:风沙天气过程中,塔中沙漠地区平均粒径Ф值2.95～3.59,标准偏差0.03～0.98;肖塘沙漠过渡带平均粒径Ф值2.93～4.56,标准偏差0.01～0.1;库姆塔格平均粒径Ф值1.55～2.92,标准偏差Ф值0.41～1.11,偏度0.11～0.31,峰度0.77～1.23。巴丹吉林沙漠平均粒径Ф值分别为1.6～1.8,毛乌素沙地为1.7～2.0,腾格里沙漠为1.7～2.3,库布其沙漠为2.1～2.4。库布其沙漠标准偏差Ф值最小0.46～0.51,巴丹吉林沙漠次之为0.55～0.68,腾格里沙漠居中为0.41～0.65,毛乌素最大为0.81～0.91。腾格里沙漠大部分样品为正偏,巴丹吉林与毛乌素为负偏。平均粒径肖塘最小,其次塔中,余下依次为库姆塔格沙漠、库布其、腾格里、毛乌素、巴丹吉林沙漠。肖塘标准偏差Ф值最高,分选最差,其它依次为毛乌素沙漠、塔克拉玛干沙漠、库姆塔格沙漠、腾格里沙漠、巴丹吉林沙漠,库布其分选最好。在频率曲线上反映肖塘、库姆塔格、库布其沙漠细颗粒偏多,塔克拉玛干沙漠、毛乌素、腾格里、巴丹吉林沙漠粗颗粒偏多。

关键词：沙漠平均粒径标准偏差偏度峰度

Sand-dust storms in china: temporal-spatial distribution and tracks of source lands

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Journal of Geographical Sciences 2001年第3期11卷 253-260页

作者： QIU Xin-fa1, ZENG Yan2, MIAO Qi-long2 (1. Urban & Resource Department, Nanjing University, Nanjing 210009, china 2. Department of Environmental Science, Nanjing institute of meteorology, Nanjing 210044, china) Urban Resource Department Nanjing University Department of Environmental Science Nanjing Institute of Meteorology

Sand-dust storm is a special natural disaster that frequently occurs in deserts and their surrounding areas. With the data published onSurface meteorological Monthly Bulletin andSurface Chart during 1971–1996, the temporal-spatial distribution and annual variation of sand-dust storms are analyzed on the basis of the case study of atmospheric processes. Furthermore, the tracks and source areas of sand-dust storms are determined with the aid of GIS. The results show that except some parts of Qinghai Province and Inner Mongolia as well as Beijing, sand-dust storms decrease apparently in time and space in recent decades in china. Sand-dust storms occur most frequently in spring, especially in April. According to their source areas, sand-dust storms are classified into two types, i.e., the inner-source and outer-source sand-dust storms. Most of the outer-source sand-dust storms move along the north and west tracks. The north-track outer-source sand-dust storms always intrude into china across the Sino-Mongolian border from Hami, a city in the eastern part ofXinjiang, to Xilin Gol, a league in Inner Mongolia, while the west-track ones intrude into china from both southern and northern Xinjiang. The source lands of inner-source sand-dust storms concentrate in the Taklimakan desert and its surrounding areas in southern Xinjiang, southern part of the Junggar Basin in north of Xinjiang, the Hexi Corridor in western Gansu Province, the dry deserts of Inner Mongolia and the Qaidam Basin in Qinghai.

关键词： sand-dust storm temporal-spatial distribution tracks source lands

PERFORMANCE OF TROPICAL CYCLONE FORECAST IN WESTERN NORTH PACIFIC IN 2015

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Tropical Cyclone Research and Review 2016年第3期5卷 47-57页

作者： Guomin Chen Xiaotu LEI Xiping ZHANG Peiyan CHEN Hui YU Rijin WAN Shanghai Typhoon institute,china meteorological administration Shanghai Typhoon institute China Meteorological Administration

The operational track and intensity forecast errors of tropical cyclones(TCs) over the western North Pacific in 2015 were evaluated on the basis of RSMC-Tokyo's "best-track" dataset. The results showed that position errors for each official agency were under 80 km, 130 km, 180 km, 260 km and 370 km at 24, 48, 72, 96 and 120 hr lead time. Stepped decreases in the values of each quantile were made at every lead times and have been made by global models from 2010 to 2015, especially for long lead time. The results of the Track Forecast Integral Deviation(TFID) show a clearly decreasing trend for most global models, indicating that the TC forecast tracks became increasingly similar to the observations. In 2015, the intensity forecast skill scores for both global and regional models were almost negative. However, the skill of EPSs' intensity forecasting has made significant progress in the past year.

关键词： tropical cyclone track intensity forecast verification skill scores

A theoretical model for mid-and low-latitude ionospheric electric fields in realistic geomagnetic fields

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A theoretical model for mid-and low-latitude ionospheric ele...

THE INTERACTION BETWEEN EDDY FLUX AND ZONAL AVERAGED FLOW IN“JUNE SUDDEN CHANGE”

中国科学院地质与地球物理研究所2008学术年会

作者： REN ZhiPeng~(1,2,3),WAN WeiXing~(1+),WEI Yong~(1,2,3),LIU LiBo~1 & YU Tao~(1,4) 1 Beijing Observatory for Space Environment,institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029, china 2 Wuhan institute of Physics and Mathematics,Chinese Academy of Sciences,Wuhan 430071,china 3 Graduate School of Chinese Academy of Sciences,Beijing 100049,china 4 National Center for Space Weather,china meteorological administration,Beijing 100081,china

The geomagnetic fields,which play important roles in the ionospheric dynamo,can greatly affect the global distribution of ionospheric electric fields,currents and other ionospheric electrodynamics *** the study of ionospheric electrodynamics phenomena,such as the longitudinal variations of ionospheric electric fields,the non-dipolar component of the geomagnetic fields must be taken into *** this paper,we deduce a theoretical electric field model for ionospheric dynamo at mid- and low-latitude which adopt a modified magnetic apex coordinates *** the new electric field model,the geomagnetic fields can be calculated from either the IGRF model or the dipole field model, and the neutral winds and conductivities are calculated based on empirical *** the dynamo equation for the electric potential is finally solved in terms of the line-by-line iteration method,and the ionospheric electric fields and currents are derived from the calculated *** model can reproduce the main features of the ionospheric electrodynamics processes,so it will be a useful tool for the investigation of the upper atmosphere and ionosphere.

关键词： ionospheric dynamo ionospheric electric fields APEX coordinates

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Acta meteorologica Sinica 1989年第1期3卷 1-9页

作者：章基嘉周顺泰 State meteorological administration Beijing Nanjing institute of meteorology Nanjing

In this paper,Eliassen-Palm theory and associated diagnostic method are used to discuss the dynamical mechanism of the interaction between eddy flux and zonal averaged flow in the sudden change of the general circulation in the Northern Hemisphere in early summer of 1982,which indicates that the northward jump of subtropic jet stream is closely related to the enhanced transport of mid-latitude eddy energy to the subtropic tro- ***,the direction of the transport is conditioned by the structure of zonal averaged *** is evident that the adjustment of zonal averaged flow responses quickly to the eddy transport during this episode. As regard to the suddenness of the change of circulation,the critical role is played by the eddy forcing,

关键词： THE INTERACTION BETWEEN EDDY FLUX AND ZONAL AVERAGED FLOW IN JUNE SUDDEN CHANGE

A new type of Shipboard meteorological Satellite Receiving-processing System

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Acta Oceanologica Sinica 2000年第1期19卷 35-46页

作者： Xie Simei Hao Chunjiang Zou Bin Jing Qiyi Liao Xiaohong Sheng Xiaowen Zhang Canrong (1. National Research Center for Marine Environment Forecasts, Beijing 100081, china 2, Second institute of china Aerospace Corporation 3. Beijing Chuanyi Electric Compan Natl. Res. Ctr. Mar. Environ. F. Beijing 100081 China Second Inst. of china Aerosp. Corp. China Beijing Chuanyi Electric Company Chinese Academy of Sciences Beijing China

The Shipboard meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12 and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be exte

关键词： Shipboard meteorological Satellite Receiving-processing System imagery processing system active gyro-control platform

Operational retrieval of Asian sand and dust storm from FY-2C geostationary meteorological satellite and its application to real time forecast in Asia

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Operational retrieval of Asian sand and dust storm from FY-2...

南极气候和海冰的时空变化特征及其与太平洋海温场的关系

第七届全国优秀青年气象科技工作者学术研讨会

作者： X. Q. Hu1,3, N. M. Lu1, T. Niu2, and P. Zhang1 1Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites (KLRCV), National Satellite meteorological Center, china meteorological administration (NSMC/CMA), Beijing 100081, china 2Centre for Atmosphere Watch & Services (CAWAS), Chinese Academy of meteorological Sciences, china meteorological administration (CMA), Beijing 100081, china 3institute of remote sensing applications, Chinese Academy of Sciences, Beijing 100101, china

This paper describes an operational retrieval algorithm for the sand/dust storm （SDS） from FY-2C/SVISSR （Stretched-Visible and Infrared Spin-Scan Radiometer） developed at the National Satellite meteorological Center （NSMC） of china. This algorithm, called Dust Retrieval Algorithm based on Geostationary Imager （DRAGI）, is based on the optical and radiative physical properties of SDS in mid-infrared and thermal infrared spectral regions as well as the observation of all bands in the geostationary imager, which include the Brightness Temperature Difference （BTD） in split window channels, Infrared Difference Dust Index （IDDI） and the ratio of middle infrared re?ectance to visible re?ectance. It also combines the visible and water vapor bands observation of the geostationary imager to identify the dust clouds from the surface targets and meteorological clouds. The output product is validated by and related to other dust aerosol observations such as the synoptic weather reports, surface visibility, aerosol optical depth （AOD） and ground-based PM10 observations. Using the SDS-IDD product and a data assimilation scheme, the dust forecast model CUACE/Dust achieved a substantial improvement to the SDS predictions in spring 2006.

关键词：

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海洋学报 2003年第6期25卷 39-47页

作者：陈锦年褚健婷许兰英中国科学院海洋研究所

　应用1973～1999年南极气温和海冰资料,分别对它们进行了统计分析,结果表明,南极的最低温度中心位于东南极大陆(东方站),这种分布特征是与南极地形相对应的.南极东方站的年平均地面气温是-55 3℃;地面最高气温出现在12月至翌1月,其温度... 详细信息

　应用1973～1999年南极气温和海冰资料,分别对它们进行了统计分析,结果表明,南极的最低温度中心位于东南极大陆(东方站),这种分布特征是与南极地形相对应的.南极东方站的年平均地面气温是-55 3℃;地面最高气温出现在12月至翌1月,其温度为-32 1℃;地面最低气温出现在8月,其温度为-68 2℃.南极各地区的地面气温具有不同的变化特征.根据温度的变化特征,将南极的气候分为4种类型:南极大陆型、南极半岛型、东南极沿岸型和海湾型.近年来南极半岛的气温有明显升高的趋势,而东南极沿岸的气温有明显下降的趋势,它们的变化呈明显的反位相.南极海冰与南极气温变化有较好的对应关系,气温升高的南极半岛的海冰有减少的趋势,而气温下降的东南极的海冰有增加的趋势.这种结果很难用温室效应来解释南极与全球气候变化的差异.东南极海冰变化与南太平洋的海温场存在密切关系,其影响过程是通过南极海冰范围的异常增加或减少,直接影响南极绕极流的冷暖结构及其异常冷暖水的经向输送,从而导致热带和副热带太平洋上层海温场的异常变化.

关键词：海冰海温场气候南极太平洋

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典型2维柱体涡激振动的数值模拟研究

同济大学学报(自然科学版) 2009年第7期37卷 862-866页

作者：方平治顾明谈建国同济大学土木工程防灾国家重点实验室中国气象局上海台风研究所

利用作者编制的基于松耦合方法的求解气动弹性问题的程序,对圆柱和方柱等典型2维柱体的涡激振动进行了数值模拟.计算结果表明:2维柱体的涡激振动存在2个锁定状态,即低折减风速条件下的流向锁定和高折减风速条件下的横向锁定;随着折减风... 详细信息

利用作者编制的基于松耦合方法的求解气动弹性问题的程序,对圆柱和方柱等典型2维柱体的涡激振动进行了数值模拟.计算结果表明:2维柱体的涡激振动存在2个锁定状态,即低折减风速条件下的流向锁定和高折减风速条件下的横向锁定;随着折减风速的增大,2维柱体的旋涡脱落模式从异向2S(2-single)变化到同向2S;伴随着旋涡脱落模式的转变,气动力和位移之间的相位差出现0→π的剧烈变化,即相位转换现象;通过对相位转换现象进行分析,给出了涡激振动是限幅振动的机理解释.

关键词：涡激振动松耦合方法相位转换