用业务有限区模式预报台风路径的初步试验          下载免费PDF全文

朱宗申  汪厚君 《应用气象学报》1994,5(3):275-283

利用国家气象中心新的有限区业务分析预报系统（ＬＡＦＳ）￣［１］，根据实例台风资料的一些参数和客观分析场，形成包含理想台风模型的模式初值，并将一个和业务有限区预报模式基本相同的、水平分辨率更高的预报模式和有限区预报模式单向嵌套，进行台风路径预报的初步试验。   相似文献   

Depositional controls on Palaeoproterozoic iron formation accumulation, Gogebic Range, Lake Superior region, USA     

Peir K. Pufahl  Philip W. Fralick 《Sedimentology》2004,51(4):791-808

Shallowing‐upward, decametre‐scale, Palaeoproterozoic iron formation cycles in northern Wisconsin record the combined effects of tectonism and changing oceanographic conditions on a storm‐dominated shelf. Cycles consist of a lower unit of laminated, Fe‐ and Si‐rich chemical mudstone that is transitional into an upper unit dominated by trough cross‐stratified chert grainstone. Grainstone lenses become progressively thicker upwards in cycles with the largest at cycle tops, where they are sharply overlain by a unit of slumped chemical mudstone. The cycles developed through progradation when offshore‐directed storm currents transported chert sand intraclasts that were formed in nearshore settings into middle and distal shelf environments. Abrupt subsidence events, probably resulting from normal faulting associated with extensional tectonism, repeatedly terminated chert grainstone accumulation and may also have generated the slumped units at cycle boundaries. The episodic storm currents are also interpreted to have transported biologically oxygenated waters from the shallow‐water, inner shelf into otherwise anoxic bottom waters of the strongly stratified distal shelf. The consequence of such transport and mixing was rapid deposition of chemical mud, mainly as precipitated Fe‐oxide. In many cases, the resultant decrease in Fe²⁺ in the water column, together with pelagic inorganic precipitation of SiO₂ and rainout of terrigenous clays, resulted in submillimetre‐ to millimetre‐thick, chemically graded laminae. The concomitant decreasing Fe²⁺/Mn²⁺ ratio also led to increasing Mn‐compound precipitation and enrichment in the upper portions of some chemically graded layers.  相似文献   

Operational mesoscale atmospheric dispersion prediction using a parallel computing cluster     

C. V. Srinivas  R. Venkatesan  N. V. Muralidharan  Someshwar Das  Hari Dass  P. Eswara Kumar 《Journal of Earth System Science》2006,115(3):315-332

An operational atmospheric dispersion prediction system is implemented on a cluster supercomputer for Online Emergency Response at the Kalpakkam nuclear site. This numerical system constitutes a parallel version of a nested grid meso-scale meteorological model MM5 coupled to a random walk particle dispersion model FLEXPART. The system provides 48-hour forecast of the local weather and radioactive plume dispersion due to hypothetical airborne releases in a range of 100 km around the site. The parallel code was implemented on different cluster configurations like distributed and shared memory systems. A 16-node dual Xeon distributed memory gigabit ethernet cluster has been found sufficient for operational applications. The runtime of a triple nested domain MM5 is about 4 h for a 24 h forecast. The system had been operated continuously for a few months and results were ported on the IMSc home page. Initial and periodic boundary condition data for MM5 are provided by NCMRWF, New Delhi. An alternative source is found to be NCEP, USA. These two sources provide the input data to the operational models at different spatial and temporal resolutions using different assimilation methods. A comparative study on the results of forecast is presented using these two data sources for present operational use. Improvement is noticed in rainfall forecasts that used NCEP data, probably because of its high spatial and temporal resolution  相似文献   

不同业务预报初值形成方案的数值模拟比较   总被引：1，自引：2，他引：1  

陈德辉  王诗文 《热带气象学报》1996,12(4):356-364

设计了一个适用于同步，双重嵌套模式的ｐ－面水平插值，双非线性正规模初值形成方案。把新方案与国家气象中心的台风路径数值预报准实时业务模式原预报初值形成方案进行了比较。所选台风个例的４８小时数值模拟结果表明，新的预报初值形成方案优于原方案。  相似文献   

Space-time structure and dynamics of the forecast error in a coastal circulation model of the Gulf of Lions     

Francis Auclair  Patrick Marsaleix  Pierre De Mey   《Dynamics of Atmospheres and Oceans》2003,36(4):309

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SCICEX Investigations of the Arctic Ocean System   总被引：1，自引：0，他引：1  

Margo H. Edwards  Bernard J. Coakley 《Chemie der Erde / Geochemistry》2003,63(4):281-328

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普里兹湾附近物理海洋学研究进展   总被引：4，自引：0，他引：4       下载免费PDF全文

蒲书箴  董兆乾 《极地研究》2003,15(1):53-64

本文主要利用近三十年来的文献资料 ,概述了普里兹湾及其邻近洋区物理海洋学研究的进展。其主要内容包括 :1 .开展普里兹湾及其邻近海域物理海洋学研究的科学意义 ;2 .现场考察的综述 ;3.水团分布及其物理特性 ;4.海流观测及其分析 ,与此同时 ,说明了在上述各个方面的研究成果和最新进展。最后指出了目前在有关的观测和研究工作中存在的不足 ,以及今后改进的建议。  相似文献   

国家气象中心集合数值预报业务系统的发展及应用   总被引：32，自引：9，他引：32       下载免费PDF全文

李泽椿  陈德辉 《应用气象学报》2002,13(1):1-15

介绍集合数值预报的基本概念，简要回顾国家气象中心的集合数值预报系统的开发过程，并概述了国家气象中心现有的中期集合数值预报业务系统的组成、集合数值预报产品的解释与应用、集合数值预报的未来发展趋势。  相似文献   

Results from One-Year Continuous Operation of a Large Aperture Scintillometer over a Heterogeneous Land Surface   总被引：8，自引：0，他引：8  

F. Beyrich  H. A. R. De Bruin  W. M. L. Meijninger  J. W. Schipper  H. Lohse 《Boundary-Layer Meteorology》2002,105(1):85-97

A large-aperture scintillometer (LAS) was operated continuouslyduring a period of more than one year over a heterogeneous land surface in Central Europeat the transition between marine and continental climates. The LAS measurements of the refractiveindex structure parameter, C_N ², were used to estimate the sensible heat flux. Thiswas possible for about 60to 80% of the time under daytime conditions during thesummer, with lower values obtained for the cold season (October to March). Using datafrom a three-week long field experiment, the LAS-based heat flux was compared with a weighedaverage of local heat flux measurements over the main land use classes (forest, agriculture,water) in the area, resulting in reasonable agreement. LAS-based heat fluxes were then used forcomparison with the heat flux values of a numerical weather prediction model. An over-predictionof the model heat flux was found in summer but the modelled values were lower than the LASderived data during the cold season.  相似文献   

A Review on the Research Progress in Operational Earthquake Forecasting (OEF) in the World     

Bi Jinmeng  Jiang Changsheng 《中国地震研究》2018,32(1):1-14

In this paper, the research progress of the Operational Earthquake Forecasting (OEF) is introduced from the major areas of concern, the concept of probability gain, hybrid model development,and the application to earthquake disaster reduction.Due to the development of OEF based on the global "Collaboratory for the Study of Earthquake Predictability (CSEP)" plan, it provides a significant technical foundation for earthquake forecast modeling and a practical foundation for solving the actual problems in earthquake preparedness and disaster mitigation.Therefore, related research and technical ideas provide inspirational and referential significance for earthquake forecasting/prediction.  相似文献