书报介绍

本篇为Charles E.Deppermann所著,1934年出版。该文系利用1930年十月至1932年二月间马尼刺之飞机记录,封该地高空情形,作概略之叙述,其中最足注意者,为各种气团特性之分析。远东热带海洋上,活动之气团可分三种:a变性极地气团(NP),包括变性极地大陆与海洋气团,即通称之东北季风·b热带海洋气团     

东亚大陆东岸的倒暖锋

一、引言 冬半年,在特定的环流条件下,极地海洋气团可以入侵东亚大陆,并进入我国造成天气影响。当极地海洋气团侵入东亚大陆后与极地大陆气团交绥,就会在东亚大陆东岸的中、高纬度地区形成近东西向单独的暖锋,它的暖区在北、冷区在南,自北向南移动,在移动过程中逐渐转成东北西南向,而后消失。以前,由于对这种暖锋注意不够,     

分析气团以论天气变化(二续)

4.太平洋及其邻近之气团贝尔格龙1930年发表之“动力气候学的真铨”(7)以气团原地之区域,分气团为四大类:冰洋气团A,极地气团P,热带气团T,及赤道气团E。又因海洋与大陆之不同,每大类再分为二小类,即有冰洋大陆气团cA,冰洋海洋气团mA,极地大陆气团cP等等八类。如     

克拉玛依的暴风

四、冷空气源地、强度和路径克拉玛依暴风既然是强冷空气入侵的结果,而这些冷空气又是从哪里来的呢?简单地说,这些冷空气来自极地海洋以及高寒大陆.为便于掌握,除起源于高寒大陆的冷气团外,凡发生于极地海洋的冷气团以其最后一次登陆前所在的海域给以定义较为方便.因此,这里说的“源地”实际上是指天气演变过程开始的地方.     

浙江省不舒适指数的地理分布

浙江省属亚热带季风气候区。夏季受温暖湿润的热带或赤道海洋气团控制,天气炎热潮湿。冬季受寒冷干燥的副极地或极地大陆气团控制,天气寒冷干燥。因此,分析我省各地冬夏两季舒适程度的地理分布有一定的意义。     

南京市降水化学特征及其来源研究

为了解南京江北地区降水化学特征,分析了2011年3—6月共25个降水日的109个降水样品中的主要水溶性离子,并利用后向轨迹模式探讨了降水气团来源.结果表明:1)南京地区3—6月降水主要受南、北2种气团影响,北方气团降水的主要离子浓度高于南方气团降水.2)海盐示踪法和相关性分析显示,降水中NO₃^-和SO₄^2-主要来自燃煤、工业排放和汽车尾气;Ca²⁺主要来自地壳源;Cl^-主要来自海洋;海洋源和陆源对Mg²⁺和K⁺都有贡献,Mg²⁺的陆源贡献大于海洋源贡献,K⁺受海洋源的影响程度要低于Mg²⁺.3)南、北气团初期降水的各离子浓度高于总降水的各离子浓度,且初期降水的主要离子的富集系数高于总降水.这说明在降水初始阶段,雨水对南京大气中污染物(气态污染物和颗粒物)的云下冲刷去除作用较强,降水的离子浓度最高,局地源对降水离子的贡献较明显.     

青岛地区降水的Gamma分布模式

按照Strahler提出的世界气侯分类,青岛地区属于湿润大陆性气候。一般气候特征是:季节对比鲜明,天气变化剧烈、全年降水丰富。夏季由于热带海洋气团侵入,降水增多。冬季则受从北部源地频繁入侵的极地大陆气团控制。按照文献的分类,青岛地区属于温带季风型气侯,降水具有明显的季节性。在这种气候背景下、为了解青岛地区的降水特征,我们在本文中做了以下工作: 1:用二参数Gamma分布模式拟合青岛地区各月和年降水量分布,建立月和年降水量分布模式。     

一次典型梅雨锋锋面结构分析

1999年梅雨期在长江中下游维持着一条典型的梅雨锋 ,锋面和梅雨雨带呈东西走向 ,从中国的四川省一直延伸到日本。锋面两侧的温度及湿度对比明显 ,并且其上有数个中间尺度的低涡沿梅雨锋依次向东移动发展 ,在长江中下游造成严重的梅雨暴雨和洪涝。文中分析了 1999年这次典型梅雨锋的锋面结构。结果表明 ,从温度场看 ,由于梅雨区对流和降水的显著发展 ,梅雨锋的低层温度对比几近消失 ,其中上部仍具有典型的上宽下窄的锋面结构 ,锋面随高度向北倾斜。在低层经向温度场呈现复杂的暖 -冷 -暖的结构 ,即北部华北平原为地面感热加热造成的相对较暖的变性极地大陆气团 ,中间为冷空气南下和降水冷却造成的相对较冷的梅雨区 ,南部是相对较暖的热带海洋气团。在这种温度场下 ,由北部低层变性暖气团与梅雨区偏冷空气形成了明显的温度对比区 ,文中定义这个区域为梅雨赤道锋。因而 ,在低层东亚梅雨区的锋区结构由梅雨赤道锋和减弱的梅雨锋构成。在 6 0 0hPa以上前者消失 ,只有单一的极锋型的梅雨锋结构。在此分析的基础上文中给出了东亚梅雨期锋面结构模型图。另外还指出 ,从假相当位温场分析 ,主要表现出梅雨区的深厚对流。降雨引起了高θse带及其南北高θse梯度区 ,其北侧高θse梯度区大致相当于梅雨锋 ,而南侧高θs     

高空槽脊对台风“天兔”（0705）变性过程中非对称降水的影响

本文基于NCEP再分析资料、TRMM卫星降水资料和RSMC最佳路径集（Best-track Dataset）资料,分析了热带气旋（TC）“天兔”变性过程中降水分布和大尺度环流的演变,并结合片段位涡反演进行修改槽脊的数值试验,研究了环流调整对TC变性过程中非对称降水的影响。结果表明:（1）“天兔”变性前降水集中在路径左侧,伴随着纬向型向经向型调整的背景环流,副热带高压南退的同时减弱西进;（2）TC降水的非对称分布与冷暖锋的相对强弱、水汽输送情况以及高空冷空气下传的落区有直接关系;（3）加强环流调整后,系统斜压性加强,与LOT（降水集中于TC路径左侧）型降水相关的环流指数增大过程随之加强,有利于LOT型降水分布进一步加强。     

中国南方准静止锋对冬季大范围冻雨的影响

利用1979—2016年1月逐日0.125°×0.125° ERA-Interim再分析资料及冻雨观测资料,通过个例合成等方法,探讨了中国南方准静止锋和冬季大范围冻雨的关系。结果表明:（1）中国南方大范围冻雨受昆明和华南准静止锋共同影响呈东西带状分布;（2）青藏高原东侧逆温之强,范围之广以及水汽之充沛的主要原因,一是冷空气常堆积在横断山脉以东和南岭山脉以北等中国广大的南方地区,其形成机制主要为冷平流和绝热冷却,地势较高地带非绝热冷却也较明显;二是700和850 hPa暖平流形成的暖层也十分宽广;三是850 hPa源自中国南海和西太平洋的湿平流输送;（3）500 hPa东亚大槽、700 hPa南支槽、850 hPa反气旋和地面蒙古冷高压为青藏高原东侧对流层低层极地大陆性气团与热带海洋性气团和热带大陆性气团交绥创造了必要的环流条件;（4）东亚冷空气爆发从青藏高原东侧南下,迫使近地面暖湿气团抬升形成华南准静止锋。同时,受青藏高原东部地形的阻挡产生冷空气堆积。当冷空气堆积到一定厚度向西爬上低纬高原时,又与南支西风相遇形成昆明准静止锋。由昆明和华南准静止锋形成的复杂锋面结构,伴随宽广而强烈的逆温有利于中国南方大范围冻雨的产生。      

Construction and Validation of an Urban Area Flow and Dispersion Model on Building Scales

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.     

Intra-Annual Variability of Diurnal Cycle Precipitation over China from 1960–2000

Characteristics of diurnal cycle precipitation over China are investigated using twice-daily observations by the China Meteorological Administration during 1960–2000. Characteristics investigated include nighttime/daytime precipitation amount（PA）, intensity, and frequency. Geographically, the region is separated into western and eastern China by the 110°E longitude. Our analysis shows that there generally is more night-time than daytime precipitation in western China, particularly in the Sichuan Basin. Over eastern China, the opposite holds true, particularly along the southeast coast. Regional average monthly daytime and night-time precipitation peaks in the same month for both western and eastern China. Over western China, monthly night-time precipitation is always greater than that during daytime, but the night-time precipitation frequency（PF） is only greater in non-summer（June–August） months. Over eastern China, daytime precipitation is greater than that in the night-time during the warm season（May–August） in both amount and frequency. The night-day difference（night-time minus daytime） in PA over western China is mainly influenced by precipitation intensity, while over eastern China the night-day difference in rainfall amount is mostly driven by PF.     

Microphysical Responses to Catalysis During a Stratocumulus Aircraft Seeding Experiment over the Sanjiangyuan Region of China

This study explores the microphysical responses to a cloud seeding operation in the Sanjiangyuan region, China. The cloud seeding was performed using a zigzag flight pattern, while the detection phase was accomplished using a back-and-forth flight pattern through the top of a stratocumulus layer. Global Position System（GPS） and Particle Measuring System（PMS） data obtained during the operation are used to determine the efective cloud area before and after the operation, diferentiate the phase states of cloud particles, and analyze changes in the concentrations of liquid cloud particles and ice crystals, the evolution of the cloud particle spectrum, and the content of supercooled water. The median diameter of liquid cloud particles in the area of the cloud-seeding operation was 3.5–18.5 μm, most cloud particles observed in the 21.5–45.5-μm size regime were ice crystals, while all particles of size 50 μm and above were in the ice phase. Changes in the concentration and typical diameter of cloud particles within 36 km downwind of the cloudseeding operation did not exceed natural fluctuations in the cloud area before the operation; however, the concentration of liquid cloud particles decreased substantially in areas with high concentrations of supercooled water（concentrations of supercooled water exceeding 0.01 g m 3）. The concentration of ice crystals within the measuring range of the Forward Scattering Spectrometer Probe（FSSP） increased substantially, the water content of ice-phase particles increased, and the average supercooled water content in the cloud decreased from（68.3± 23.1）% before the operation to（34.2± 12.4）%. The efects of cloud seeding were more pronounced in parts of the cloud where the content of supercooled water was higher. Little to no efects were observed in parts of the cloud with low concentrations of supercooled water.     

Uncertainty in Dust Budget over East Asia Simulated by WRF/Chem with Six Different Dust Emission Schemes

In this study, the dependence of dust budgets on dust emission schemes is investigated through the simulation of dust storm events, which occurred during 14–25 March 2002, over East Asia, by the Weather Research and Forecasting with Chemistry（WRF/Chem） model coupled with six dust emission schemes. Generally, this model can reasonably reproduce the spatial distribution of surface dust concentration; however, the simulated total dust budget differs significantly with different emission schemes. Moreover, uncertainties in the simulated dust budget vary among regions. It is suggested that the dust emission scheme affects the regional dust budget directly through its impact on the total emitted dust amount; however, the inflow and outflow of dust aerosols simulated by different schemes within a region also depend on the geographical location of the dust emission region. Furthermore, the size distribution of dust particles for a specific dust emission scheme has proven to be important for dust budget calculation due to the dependence of dust deposition amount on dust size distribution.     

Impact of Preceding Summer North Atlantic Oscillation on Early Autumn Precipitation over Central China

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.     

Intercomparison of Surface Radiative Fluxes in the Arctic Ocean

Recent satellite data analysis has provided improved data sets relevant to the surface energy budget in the Arctic Ocean. In this paper, surface radiation properties in the Arctic Ocean obtained from the Surface Radiation Budget（SRB3.0） and the International Satellite Cloud Climatology Project（ISCCP-FD） during 1984– 2007 are analyzed and compared. Our analysis suggests that these datasets show encouraging agreement in basin-wide averaged seasonal cycle and spatial distribution of surface albedo; net surface shortwave and all-wave radiative fluxes; and shortwave, longwave, and all-wave cloud radiative forcings. However, a systematic large discrepancy is detected for the net surface longwave radiative flux between the two data sets at a magnitude of ~ 23 W m–2, which is primarily attributed to significant differences in surface temperature, particularly from April to June. Moreover, the largest difference in surface shortwave and all-wave cloud radiative forcings between the two data sets is apparent in early June at a magnitude of 30 W m–2.     

气象服务文档的自动化生成

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,     

一次雷击火灾事故个例调研与分析

<正>1"6.3"乙烯厂雷击火灾事故概况2008年6月3日18:20左右,茂名地区开始转为雷暴雨天气。18:56,茂名石化乙烯厂裂解车间2号装置发生火灾,火势于当日20:30基本被控制,于21:50彻底被扑灭。火势烧毁装置的部分管线和设备,无人员伤亡,没有造成环境污染,茂名乙烯厂的     

重读《四十五年来我参加之中国观象事业》之后

蒋丙然老前辈是中国近代气象事业的先行者,也是主要奠基人之一。他在75岁高龄时（1957年）撰写的《四十五年来我参加之中国观象事业》一文（以下简称“蒋文”）,可以认为是一篇高度概括了他一生科学事业（主要是气象事业）的自传。它是欲知中国早期近代气象事业发展过程的人,不可不熟习的重要文献。但似有某些不足之处。     

重覆冰区30 m标准避雷铁塔荷载计算

<正>贵州地处云贵高原,介于103°37′～109°35′E、24°37′～29°13′N之间,地势西高东低,自中部向北、东、南三面倾斜,平均海拔1100 m左右,以高原山地居多。受大气环流及地形等影响,贵州省成为我国出现覆冰现象较重的地区之一。资料显示,1972