一种测量大气中气溶胶浓度的仪器

前言近几十年来,地球环境的现状及变化引起了人们日益严重的关注,科学家们开始了对大气物理、化学和动力特性的研究。这类研究中所涉及的许多参数一直未曾能够充分了解,因此,我们于1972年决定开展对流层和平流层中诸如爱根核这样细微的气溶胶的研究工作。为此目的,我们根据威尔逊云室的原理设计了一种气球运载的爱根核计数器。由于我们希望能够同时对其它的大气参数进行多种测量,所设计的仪器就必须简单轻巧。过去几年中,我们进行了多次气球飞行测试,并对仪器做出改进,现在已经获得了一种用于实际测量的较为理想的仪     

长期温度预报“阿戴(Adem)”方法的应用

Adem的半球范围内的热力学模式,早用于对流层—海洋—大陆系统的月平均或季节温度的距平预报。继而又用来研究气候波动,最近又把这个模式推广用于预报全球未来的气候变化,都得到一些较好的结果。我们为了提高长期数值预报的准确程度,试用Adem的模式作出北半球海陆范围内的近地面气温月平均距平的预报。并把结果与巢纪平等的滤波方法作了比较。 一、Adem模式简述 1、模式所用的符号 本文与所用的符号与Adem模式的有关论文是相同的,说明如下:H表示大气辐射上界的高度。Δt表示时间间隔(一个月或一个季)。T_m表示对流层的     

对高空观测中几个特殊问题的处理意见

1.在探空记录中,由于突然停电或仪器停转几分钟等原因,造成对流层顶及其附近信号缺测时,在温度线按规范规定连虚线后,往往缺测起始点可能不是对流层顶,但却符合对流层顶条件.这时对流层顶应按缺测处理. 2.遇到大雨或高空有很强的下沉气流时,气球会下沉,有时甚至下沉二、三十     

探空气球漂移特征及对三角形法计算散度的影响

利用2006—2013年南京站、安庆站和杭州站探空资料,讨论华东地区探空气球的漂移特征。设计不考虑气球漂移、考虑全部气球漂移和考虑部分气球漂移3个试验,比较3种情况下三角形法计算的散度差异。结果表明:气球漂移主要受大气环流及其变化影响,纬向上7月和8月气球随高度增加,先向东漂移、后向西漂移,其他月份以向东漂移为主,冬季漂移距离大;经向上受季风影响明显。考虑全部和部分气球漂移与不考虑气球漂移的散度对比表明,平均绝对偏差各月在对流层顶附近均有极大值;相对偏差季节分布明显,前者在6—9月较大,极大值略大于7%,后者冬季大,1月在200 hPa达到25%,在50 hPa超过50%。因此,利用三角形法计算散度所在层次较高或所使用资料中传统探空和特种探空并存时,均需考虑气球漂移影响。     

自制遥控放球器

目前我国高空气象探测的主要手段是使用气球携带仪器升空观测。无论是刮风下雨,还是严寒酷暑,都要由人在施放场地施放气球。我们经多次试验,制造了一种遥控放球器,从兰州观测站和甘南州局探空组的实际使用情况来看,该放球器设备简单,制做方便,适用于一般陆地探空站。     

使用系留气球进行气象观测的几个力学问题

在没有铁塔和高层建筑物设施的地方,一般都用系留气球携带观测仪器升空到几百公尺的高度上,进行有关气象要素的短时间测量。现我们就实际工作中遇到几个涉及力学的问题,进行一些理论分析和计算。一、系留气球的升空高度     

中国探空气球水平漂移总体特征分析

利用2003年4月至2008年8月全国119个探空台站采集的气球漂移信息,分析了中国探空资料水平漂移距离、漂移距离标准差以及漂移方向的分布特征。研究表明:各层探空气球的漂移距离冬季明显大于夏季;一般探空气球的漂移距离随探空高度的增加而增大,但在夏季南方地区由于风向随高度的反转会出现探空气球水平漂移距离随高度减小的状况。探空气球水平漂移距离的标准差随高度增加而增大,且其大值区分布基本上与水平漂移距离的大值区分布一致。从气球漂移方向上看,冬季的情况相对简单,全国各探空台站各层的漂移方向基本以向东为主;但夏季探空气球漂移的方向比较复杂,在对流层低层,全国各台站漂移方向基本以向东为主,而在对流层高层和平流层,北方地区漂移方向基本向东,而南方地区以向西为主。     

谈谈测风气球的颜色

气象台站每天施放测风气球,它的颜色并非都是一样的,有时用红色球,有时用白色球,有时又用黑色或黄色球。测风气球为什么要选择球皮颜色呢?我们知道,测风气球是用经纬仪进行观测的。在用经纬仪观测飞升中的测风气球时,为了容易找到空中的球影,延长观测时间,获得更多的高空风资料,在施放测风气球时,必须根据当时的天空状况来选择球皮颜色。     

使用电解水制氢设备的几点体会和建议

我站自1973年10月安装使用我区自行设计的气象专用电解水制氢设备以来,该套设备满足了我站每天两次探空气球一次测风气球所须氢气的供应,同时也经受住了连续一年半每天三次探空气球及两个多月每天四次试验气球所须氢气的考验。几年来,该套设备运转基本正常,没有出现任何事故。以它优良的性能,优越的工作条件而深受高空观测人员欢迎。我们的体会是:一、工作安全可靠,性能稳定     

热带定高气球系统

全球大气研究计划第一次全球实验(FGGE)观测阶段的主要目的是要取得全球的气象观测资料和海洋观测资料。在现有的观测系统中,热带地区和南半球存在着严重的观测空白区,为了弥补这些空白区,需要临时使用一些特殊的观测工具。由美国国家大气研究中心(NCAR)提出的、业经世界气象组织采纳的热带定高气球系统,即为其中主要的一种。热带定高气球系统(TCLBS)是全球大气试验飞机下投式探空仪计划的补充,在FGGE实施年的两个特殊观测期1979年1—2月和5—6月由NCAR负责实施。其观测资料将由泰罗斯-N的ARGOS资料收集和观     

Polar night vortex breakdown and large-scale stirring in the southern stratosphere

The present paper examines the vortex breakdown and large-scale stirring during the final warming of the Southern Hemisphere stratosphere during the spring of 2005. A unique set of in situ observations collected by 27 superpressure balloons (SPBs) is used. The balloons, which were launched from McMurdo, Antarctica, by the Stratéole/VORCORE project, drifted for several weeks on two different isopycnic levels in the lower stratosphere. We describe balloon trajectories and compare them with simulations obtained on the basis of the velocity field from the GEOS-5 and NCEP/NCAR reanalyses performed with and without VORCORE data. To gain insight on the mechanisms responsible for the horizontal transport of air inside and outside the well-isolated vortex we examine the balloon trajectories in the framework of the Lagrangian properties of the stratospheric flow. Coherent structures of the flow are visualized by computing finite-time Lyapunov exponents (FTLE). A combination of isentropic analysis and FTLE distributions reveals that air is stripped away from the vortex’s interior as stable manifolds eventually cross the vortex’s edge. It is shown that two SPBs escaped from the vortex within high potential vorticity tongues that developed in association with wave breaking at locations along the vortex’s edge where forward and backward FTLE maxima approximately intersect. The trajectories of three SPBs flying as a group at the same isopycnic level are examined and their behavior is interpreted in reference to the FTLE field. These results support the concept of stable and unstable manifolds governing transport of air masses across the periphery of the stratospheric polar vortex.     

甚高频多普勒多气球跟踪系统

一个多路径传输误差小、造价低、重量轻的甚高频多普勒多气球跟踪系统已研制完成.本文对其原理、设计和性能作了概述.该系统在珠江三角洲观测实验中取得了40km双气球平飘轨迹和30km内水平扩散参数,为中距离低空大气污染物输送、扩散的拉氏轨迹和大气污染模式研究提供了一个新的探测手段.     

湿急流的结构及形成过程

利用比较稠密的无线电探空和气球测风观测网,通过对华北夏季一次暴雨过程的三维流场和湿度场的分析,揭示了湿急流的结构和形成过程。湿急流是指低层空气在湿不稳定大气的上升过程中,不断加速形成一支斜穿整个对流层的自下而上的急流。在湿急流附近,凝结饱和区的分布和发展过程,似乎表明水汽在急流形成过程中起了一种主动作用。湿急流在对流层顶附近和副热带急流合併,并使副热带急流的动能增加。这似乎启示,湿斜压过程可能是大气环流中的基本过程之一。     

探空气球施放筒设计

探空气球的充灌和施放是高空气象观测工作的重要组成部分.目前高空观测中雷达跟踪探空仪、探空信号接收和数据处理都已经实现自动化,只有探空气球的充灌和施放是人工操作,气球充灌氢气有一定危险性,且至少需要一个观测员来完成施放气球工作.该文在分析探空气球充灌和施放各环节工作的基础上,介绍了一种探空气球施放筒的设计方案,以及在业务试验中存在的问题和改进方法,为高空气象观测系统的全程自动化创造条件.     

Effect of the plume rise and wind speed on extreme value of air pollutant concentration

Summary Extreme values of the ground level concentration of air pollutants were evaluated as a function of plume rise Δh, and wind speed in two cases. Firstly, when a plume rise depends on the downwind distance x, and secondly, with a constant plume rise (i.e., independent on x). Also, the extreme values for the effective stack height were evaluated for different stability classes. The maximum value of the ground level concentration was obtained in unstable stability when plume rise depends on x and in the neutral stability when plume rise independent on x. Also, in stable case, the extreme values of the ground level concentration of air pollutants showed similar values in the two cases when plume rise depends on x, and with constant plume rise. Finally, it was found that the extreme value of the ground level concentration occurred near the stack and after that it was decreases in all stabilities.     

A standing wave in stable drainage flow induced by a small industrial facility

A small town close to a lead/zinc smelter was experiencing unusually high concentrations of sulfur dioxide during certain drainage flow conditions. The episodes occurred in situations where the buoyant plume rise should have been sufficient to eliminate any excessive ground level concentrations resulting from building wake effects. A field study was initiated using visible oil fog, tracer gas releases, and constant volume balloons. The resulting data revealed that a standing wave was being induced in the flow across the smelter bringing pollutants from as high as 150m agl down to 30m agl over the nearby town. The existence of the wave is attributed to the combined effects of the smelter buildings and the thermal forcing supplied by smelter operations. Data are presented characterizing the wavelike disturbance and documenting the meteorological conditions under which it occurs. A comparison is made between the simulated pollutant impacts using the tracer gas data and model predictions using the Industrial Source Complex dispersion model.     

Vertical profiles of small-scale temperature structure in the atmosphere

Measurements of air temperature fluctuations at frequencies from 1–100 Hz have been made with instruments carried by free-flying balloons. Structure functions and spectra of the temperature field have been calculated for various heights within the range 0.1–8 km above ground. The frequent occurrence of shallow regions, possibly layers, which exhibit locally enhanced values of the structure coefficient has been confirmed.     

结合第8届国际探空仪系统比对试验探讨国产气球施放高度

根据阳江探空站高空气象探测用750g气象气球施放的实际高度的现状,结合中国大探中心组织国产GPS探空仪在阳江用国产2000g气象气球比对试验时施放的高度以及广东阳江第8届国际探空仪系统比对期间施放的实际高度,探讨雨天和高空相对湿度较大的气象条件下对国产气象气球施放高度的影响。结果显示,雨天或高空相对湿度较大时,对国产现有的气象气球施放的高度存在较大的影响。研究表明,解决了国产气象气球的球皮防雨、防潮问题,很大程度上解决了国产气象气球施放高度不稳定的难题。     

Sensitivity of the IAP two-level AGCM to surface albedo variations

Summary Two numerical experiments were performed for sensitivity study of surface albedo, one was a control run in which the albedo values for snow-free surfaces were prescribed as constant; the other was a sensitivity run in which an albedo with seasonal variation was incorporated into the model show that the simulation of precipitation is sensitive to the surface albedo variations, especially those over Eastern Asia and the Sahara. Changes in surface albedo also have an impact on the monthly mean sea level pressure, especially on the July-mean Western Pacific subtropical high. Surface air temperature decreased over most of the Eastern Asia but increases over most of the Antarctica in July.With 6 Figures