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Use of the advanced microwave sounding unit data to improve typhoon prediction

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Progress in Natural Science:Materials International 2009年第3期19卷 369-376页

作者： Guo Deng a,*, Dalin Zhang b, Tong Zhu c, Angsheng Wang d a National Meteorological Center, Beijing 100081, china b department of {2. and Oceanic Science, University of Maryland, Maryland 2.742. USA c Cooperative institute for Research in the Atmosphere, Colorado State University, Colorado 8052., USA d institute of {2. Physics, Chinese Academy of sciences, Beijing 10002., china National Meteorological Center Beijing 100081 China department of atmospheric and Oceanic Science University of Maryland Maryland 20742 USA Cooperative institute for Research in the Atmosphere Colorado State University Colorado 80523 USA institute of atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The effects of incorporating the advanced microwave sounding unit (AMSU-A) data with a modified Zhu-Zhang-Weng vortex- bogussing algorithm on typhoon prediction are examined through the use of the PSU/NCAR Mesoscale Model version 5 (MM5). The AMSU-A data contain the vertical distribution of the retrieved temperature from satellite brightness temperature, with the geopo- tential height and wind fields derived through a series of statistical and diagnostic calculations. The advantages of the modified vortex- bogussing algorithm include the incorporation of realistic asymmetric typhoon structures, the balanced dynamics with the background field, the easiness to implement and the effcient computations. To test the effciency of this vortex-bogussing algorithm, the Typhoon Dan event in 1999 is simulated by incorporating the derived AMSU-A fields into the initial conditions of the MM5 modeling system. Results show significant improvements in the track and intensity of the storm, as compared to the simulation without the AMSU-A data. Therefore, this modified vortex-bogussing algorithm can be easily implemented on any typhoon modeling system, which will improve the real-time forecast of tropical cyclones.

关键词： AMSU Satellite retrieval Typhoon prediction

Low-frequency fluctuations in the magnetosheath: Double Star TC-1 and Cluster observations

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Science china(Technological sciences) 2008年第10期51卷 1626-1638页

作者： DU Jian1,2.WANG Chi1, SONG Pu3,4 & ZHANG TieLong5 1 State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of sciences, Beijing 100190, china 2.Graduate School, Chinese Academy of sciences, Beijing 100049, china 3 Earth, Environmental and atmospheric sciences department, University of Massachusetts, Lowell, Mas-sachusetts MA 01854, USA 4 Center for atmospheric Research, University of Massachusetts, Lowell, Massachusetts MA 01854, USA 5 Space Research institute, Austrian Academy of sciences, Graz A-8010, Austria State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Graduate School Chinese Academy of Sciences Space Research institute Austrian Academy of Sciences

The magnetic field variations are analyzed in the range of time periods from 4 s to 2.0 s in the magnetosheath observed by the Double Star TC-1 and Cluster in 2.04. The characteristics of the magnetic field fluctuations are strongly controlled by the angle between the upstream interplanetary magnetic field (IMF) and the normal of the bow shock. Generally speaking, the magnetic field fluctuations in the quasi- parallel magnetosheath are more intense than those in the quasi-perpendicular ones. Almost purely compressional waves are found in the quasi-perpendicular magnetosheath. With the increase of the local plasma β, both the magnitude and direction of the magnetic field fluctuate more intensely. There exists an inverse correlation between the local temperature anisotropy T⊥/T|| and the plasma β.

关键词： low-frequency fluctuations magnetosheath MHD instabilities

Retrospect and prospect: advances and future strategies in climate research

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Progress in Natural Science:Materials International 2003年第4期 3-8页

作者： YE Duzheng and LU Jianhua(institute of atmospheric Physics, Chinese Academy of {2., Beijing 10002., china) A visiting scholar in department of meteorology, University of Hawaii institute of atmospheric Physics Chinese Academy of Sciences Beijing 100029 China A visiting scholar in department of meteorology University of Hawaii

A brief review of the progress in climate research and a prospect on its further development in the 2.st century is pre-sentcd. Some key findings including the eoncept of climate system, the discovery of climatic multi-equilibrium and abrupt climate changes, and the recognition of human activities as an important force of climate change made breakthroughs in climatologv possible during last few decades. The adaptation to climatic and global change emerged as a new aspect of climatic research during the 1990s. Climate research will break through in the observation of the global system, in the analysis of mass data, in the deepening of research on the mechamsm of climatic change, and in the improvement of models. In the applied fields of climate research, there will be substantial progress in the research on adaptation to global change and sustainable development, on orderly human activities, and climate modification.

关键词： advances climate system global change abrupt climate change orderly human activity.

强降水过程中垂直螺旋度和散度通量及其拓展形式的诊断分析

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物理学报 2009年第11期58卷 8094-8106页

作者：冉令坤楚艳丽中国科学院大气物理研究所北京100029 中国气象局北京市城市气象研究所北京100089

在垂直螺旋度的基础上,定义了散度通量,水汽垂直螺旋度和水汽散度通量三个宏观物理量.针对两次强降水过程,利用NCEP/NCAR实时分析资料对这些物理量进行诊断分析,结果表明,这些物理量能够比较准确地综合表征强降水系统所共有的典型动力... 详细信息

在垂直螺旋度的基础上,定义了散度通量,水汽垂直螺旋度和水汽散度通量三个宏观物理量.针对两次强降水过程,利用NCEP/NCAR实时分析资料对这些物理量进行诊断分析,结果表明,这些物理量能够比较准确地综合表征强降水系统所共有的典型动力场垂直结构,进而与降水系统的发展演变密切相关.这些物理量垂直积分的异常值区与观测的6h累积地面降水具有良好的对应关系,表明它们对强降水的落区和降水系统的发展移动具有良好的指示预测意义.NCEP-GFS每日四次6h预报场资料的计算表明,垂直螺旋度和散度通量及其拓展形式(水汽垂直螺旋度和水汽散度通量)对强降水系统的发展演变具有一定的预报能力,并且水汽散度通量是比较突出的对暴雨具有指示预报意义的动力预报因子.

关键词：垂直螺旋度散度通量水汽垂直螺旋度水汽散度通量

The relationship between middle stratiform clouds and large scale circulation over eastern china

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The relationship between middle stratiform clouds and large ...

Variations of Snow Temperature and their Influence on Snow Cover Physical Parameters in the Western Tianshan Mountains,china

中国气象学会2.06年年会“气候变化及其机理和模拟”分会场

作者： Yunying Li1,2.and Hong Gu2. State Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics (LASG), {2. of atmospheric Physics, Chinese Academy of sciences, Beijing, china. 2.{2. of meteorology, PLA University of Science and Technology, nanjing,china.

Eastern china is the globally unique land region with lots of middle stratiform clouds in cold seasons. The distribution of this specific stratiform cloud is determined by three main factors, viz, rel

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Journal of Mountain Science 2011年第6期8卷 827-837页

作者： CHEN Xia WEI WenShou LIU MingZhe GU GuangQin Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Hebei Key Laboratory for meteorology and Eco-environmen Shijiazhuang 050021 China HeBei Climate Center Shijiazhuang 050021 China institute of Desert meteorology China Meteorological Administration Urumqi 830011 China Tianshan Station for Snow-cover and Avalanche Research Chinese Academy of Sciences Urumqi 830011 China

This article discussed about snow temperature variations and their impact on snow cover parameters. Automatic temperature recorders were used to sample at lo-minute intervals at the Tianshan Station for Snow-cover and Avalanche Research, Chinese snow temperature Academy of sciences. lo-layer and the snow cover parameters were measured by the snow property analyzer （Snow Fork） in its Stable period, Interim period and Snow melting period. Results indicate that the amplitude of the diurnal fluctuation in the temperature during Snow melting period is 1.62.times greater than that during Stable period. Time up to the peak temperature at the snow surface lags behind the peak solar radiation by more than 2.5 hours, and lags behind the peak atmospheric temperature by more than 0.2.hours during all three periods. The optimal fitted function of snow temperature profile becomes more complicated from Stable period to Snow melting period. 2. h temperature profiles in Stable period are the optimal fitted by cubic polynomial equation. In Interim period and Snow melting period, temperature profiles are optimal fitted by exponential equation between sunset and sunrise, and by Fourier function when solar radiation is strong. The vertical gradient in the snow temperature reaches its maximum value at the snow surface for three periods. The peak of this maximum value occurs during Stableperiod, and is 4.46 times greater than during Interim period. The absolute value of temperature gradient is lower than 0.1℃ cm-1 for 30 cm beneath snow surface. Snow temperature and temperature gradient in Stable period-Interim period indirectly cause increase （decrease） of snow density mainly by increasing （decreasing） permittivity. While it dramatically increases its water content to change its permittivity and snow density in Snow melting period.

关键词： Snow temperature Vertical temperaturegradient Optimal fitting function Snow density Western Tianshan Mountains china

AN OBSERVATIONAL STUDY OF THE MESO-β SCALE MOVING SYSTEMS IN THE MEIYU FRONT

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Acta Meteorologica Sinica 1988年第4期 436-449页

作者：余志豪陆汉城范献忠 department of atmospheric {2. nanjing University institute of meteorology PLA Air Force

The new concept and analysis method for the rainfall peak are introduced in this paper,and an obser-vational study of a heavy rain case in the Meiyu front has been made with finer radiosonde and *** has found in this case that there are a lot of meso-β scale systems associated with the rainfall peaksin the Meiyu ***-β scale systems can be divided into two kinds,i.e.,the moving and standing *** moving type is characterized by the unstable gravity wave and has a path corresponding to the meso-α scalerain belts in the *** discussion about the meso-β systems is made by using the symmetric andtransversal wave instability theory.

关键词： SCALE MOVING SYSTEMS IN THE MEIYU FRONT AN OBSERVATIONAL STUDY OF THE MESO

Three-dimensional hydrodynamic model of Xiamen waters

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Acta Oceanologica Sinica 2003年第2期22卷 151-170页

作者： WenShenghui CaiSong TangJunjian CaiQifu ThirdinstituteofOceanography StateOceanicAdministrationXiamen361005China departmentofatmospheric{2. PekingUniversityBeijing100871China SchoolofMathematicsandStatistics WuhanUneversityWuhan430072China

A semi-implicit and Eulerian - Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-moment turbulence closure model and transport equations of salinity and temperature. The simulation for flooding and drying of mudflats has been improved. The model is applied to Xiamen waters. Based on extensive survey data, water level elevation, temperature and salinity field along the eastern open boundary and at the Jiulong River inlets and runoffs are analyzed, specified and calibrated. The computed results show good agreement with the measured data, reproduce flooding, emergence of large and complex mudflat region.

关键词： Semi-implicit finite difference scheme Eulerian - Lagrangian approach three-dimensional shallow water flow Xiamen waters

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年代际气候变化的研究进展

山东气象 2004年第1期24卷 5-9页

作者：孙照渤陈海山南京气象学院大气科学系江苏南京210044

年代际气候变化是月、季、年际气候变化及预测的背景。2.世纪90年代以来,年代际气候变化的研究引起了国内外学者的极大关注,开展了大量富有成效的研究工作。本文从大气环流、中国气温和降水、海洋以及海气系统等4个方面对年代际气候变... 详细信息

年代际气候变化是月、季、年际气候变化及预测的背景。2.世纪90年代以来,年代际气候变化的研究引起了国内外学者的极大关注,开展了大量富有成效的研究工作。本文从大气环流、中国气温和降水、海洋以及海气系统等4个方面对年代际气候变化的研究进展进行了总结,提出了年代际气候变化,尤其是东亚地区的年代际气候变化研究需要进一步解决的科学问题。

关键词：年代际气候变化气候预测大气环流气温降水海洋