首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到10条相似文献,搜索用时 46 毫秒
1.
The networking status of journals reflects their academic influence among peer journals. This paper analyzes the cited and citing environments of this journal, Advances in Atmospheric Sciences (Adv. Atmos. Sci.), using methods from social network analysis. Since its initial publication, Adv. Atmos. Sci. has been actively participating in the international journal environment and international journals are frequently cited in Adv. Atmos. Sci. Particularly, this journal is intensely interrelated with its international peer journals in terms of their similar citing patterns. The international influence of Adv. Atmos. Sci. is comparatively bigger than other Chinese SCI journals in atmospheric sciences as reffected by total cites to Adv. Atmos. Sci. and the total number of international journals citing it. The academic visibility of Adv. Atmos. Sci. is continuing to improve in the international research community as the number of reference citation it receives in its peer journals internationally increases over time.  相似文献   

2.
This paper presents a numerical model that simulates the wind fields, turbulence fields, and dispersion of gaseous substances in urban areas on building to city block scales. A Computational Fluid Dynamics(CFD) approach using the steady-state, Reynolds-Averaged Navier-Stokes(RANS) equations with the standard k-ε turbulence model within control volumes of non-uniform cuboid shapes has been employed. Dispersion field is computed by solving an unsteady transport equation of passive scalar. Another approach based on Gaussian plume model is used to correct the turbulent Schmidt number of tracer, in order to improve the dispersion simulation. The experimental data from a wind tunnel under neutral conditions are used to validate the numerical results of velocity, turbulence, and dispersion fields. The numerical results show a reasonable agreement with the wind tunnel data. The deviation of concentration between the simulation with corrected turbulent Schmidt number and the wind tunnel experiments may arise from 1) imperfect point sources, 2) heterogeneous turbulent difusivity, and 3) the constant turbulent Schmidt assumption used in the model.  相似文献   

3.
区域气候模式对我国冬春季气温和降水预报评估   总被引:3,自引:1,他引:2       下载免费PDF全文
使用国家气候中心全球海气耦合模式嵌套区域气候模式(RegCM_NCC)对1983 2002年冬季以及1984-2003年春季我国平均气温和降水进行了数值回报试验,并对2003-2007年进行实时预报.结果表明:区域气候模式20年冬、春季平均气温的回报与实况在分布形态上较为相似,我国大部地区平均气温预报与实况接近;模式回报的冬、春季降水量的分布形态与实况有较大差异,全国大部地区模式回报降水量比实况偏多,西南地区降水量误差最大.使用国家气候中心气候预测室的业务预报评分(P)和距平相关系数(ACC)等5个评估参数对模式的回报和预报进行了评估分析,结果表明:该模式对我国冬、春季平均气温和降水具有一定的跨季度预报能力.大多数年份冬,春季平均气温的P评分在60以上,冬、春季平均气温多年平均分别为66.4和67.8;大多数年份的冬、春季降水评分为60~75,冬、春季降水多年平均分别为69.9和65.6.  相似文献   

4.
1956年1月到3月上旬亚洲上空大气环流的结构   总被引:1,自引:2,他引:1  
邬鸿勋  陈隆勋 《气象学报》1956,27(4):361-381
根据1956年1月到3月上旬亚洲地区高空资料,对亚洲大陆上空的大气环流进行了探讨。作者得出了下列的事实: 1)在上述时间期限内的平均情况表明,亚洲大陆上空存在着二支急流。这二支急流在东经140°经度上已经汇合。 2)二支急流在东亚部分都表现有向东加速的现象。南支急流自东经75°就开始明显地向东加速。而北支急流的加速自东经100°附近才开始。 3)东亚大陆上大气的斜压性主要是集中在高原的附近。 另外对上述现象也作了一些初步的研究。作者认为西藏高原的存在对大气环流有下列三方面的影响: 1)高原加强了大气的斜压性,并且在高原南方形成垂直环流。因而强烈的加速了南支急流。 2)高原的存在使得南北二支急流在其东侧互相接近,显然地影响了急流的加速。 3)高原保证了南支急流强大而且稳定,这就是说每天每年同季的变化都小。  相似文献   

5.
1 气象服务文档自动化生成的设计思路 目前大部分的气象信息文档以Word进行编辑和处理,并且Office软件支持各种编程语言的再开发,尤其是其自带了一套寄生式的语言VBA(Visual Basic Application),这给编程带来了极大的便利。但是VBA功能很弱,不能脱离所依附的宿主程序环境,不能被编译为独立的可执行文件,给程序运行带来了很大的不便利。相比之下,  相似文献   

6.
Absract  On the data of 13-year (1994–2006) measurements, during January to June, of the atmospheric aerosol characteristics in Dolgoprudny, Moscow region, effects of the city of Moscow on aerosol contamination of the surface air is analyzed. A relative increase is estimated of concentrations of particles of various sizes within the diameter range of 0.01 to 10 μm under conditions of airflow from the city of Moscow, along with changes in concentrations of cloud condensation nuclei and ice nuclei in the air. It is shown that percentage of the aerosol particles from Moscow in the total aerosol concentration within certain size ranges reaches 30% in winter months and 45% in summer ones. The aerosol transported from the city contains a significant amount of hygroscopic particles. The cloud nuclei concentration in June increases by a factor of 2 in the cases of airflow from the city. Original Russian Text ? N.O. Plaude, E.A. Stulov, N.A. Monakhova, M.V. Vychuzhanina, E.V. Sosnikova, N.P. Grishina, 2007, published in Meteorologiya i Gidrologiya, 2007, No. 12, pp. 35–43.  相似文献   

7.
Summary A model for biologically-effective ultraviolet radiation (UVR) of the sun is described, which allows the calculation of diffuse irradiance on inclined surfaces. A model is presented, for which isotropic scattered and reflected radiance are assumed. Using the horizon as a borderline between the upper and lower hemisphere, the scattering phenomena in the atmosphere for UVR are discussed. In contrast to models for other solar spectral ranges, the radiation field of UVR is close to isotropic. Only the horizon darkening by the long optical pathlengths was included in the model. This term was quantified by the UV albedo.Dedicated to O. Univ.-Prof. Dr. F. Steinhauser.With 1 Figure  相似文献   

8.
This study examined the impact of the preceding boreal summer(June–August) North Atlantic Oscillation(NAO) on early autumn(September) rainfall over Central China(RCC). The results show that a significant positive correlation exists between the preceding summer NAO and the early autumn RCC on the interannual timescale. In order to understand the physical mechanism between them, the role of ocean was investigated. It was found that the strong summer NAO can induce a tripole sea surface temperature anomaly(SSTA) in the North Atlantic; this SSTA pattern can persist until early autumn. The diagnostic analysis showed that the tripole SSTA pattern excites a downstream Atlantic-Eurasian(AEA) teleconnection, which contributes to an increase in RCC. The circulation anomalies related to SSTA caused by the weak NAO are opposite, so the RCC is less than normal. The results imply that the preceding summer NAO may be regarded as a forecast factor for the early autumn RCC.  相似文献   

9.
甘肃省近五千年气候变迁的初步研究   总被引:5,自引:1,他引:5  
董安祥 《高原气象》1993,12(3):243-250
  相似文献   

10.
Hot-wire anemometers were used to measure air temperature and the three velocity components of the wind within and above a maize canopy. From digitized anemometer outputs, correlation coefficients for vertical heat flux and turbulent momentum transfer were calculated. A comparison of these coefficients with profiles of mean wind speed and mean temperature indicates that the main features of the turbulence may be explained in terms of the usual mixing-length theory. Instantaneous records of heat and momentum flux, however, indicate the existence of other competing turbulent mechanisms due to the unsteady, non-equilibrium nature of the turbulent flow. Regimes of flow dominated by mechanical and/or thermal mixing are indicated. Spectral results show that high shear and turbulent intensity levels as well as the presence of the maize leaves and stalks as vortex-shedding surfaces complicate the energy transfer mechanism. An energy balance between radiation and convection reveals that the energy budget is primarily a balance between solar radiation and the flux of latent heat.Contribution of the Sibley School of Mechanical and Aerospace Engineering, Cornell University, in cooperation with the Agricultural Research Service, U.S. Department of Agriculture, Ithaca, N.Y., U.S.A. and the Cornell University Agricultural Experiment Station. Department of Agronomy Series No. 1116.Sibley School of Mechanical and Aerospace Engineering, Cornell University; U.S. Department of Agriculture, Gainesville, Florida Section for Estuary and Fjord Studies, River and Harbour Laboratory, Technical University of Norway, Trondheim, Norway; State Univ. of New York at Buffalo; and U.S. Department of Agriculture and Cornell University; respectively.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号