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The structure of atmospheric boundary layer determines the ability of atmospheric dispersion and has an essential impact on airborne aerosols. In this paper, the data of a radio sounding experiment held in Dongguan National Meteorological Observation Station, which is in a coastal city in Pearl River Delta, as well as the data of atmospheric aerosols, were utilized in order to analyze the characteristics of atmospheric boundary layer and its effects on surface aerosol concentrations. The results are showed at follows: the local circulations, associated with dominant winds, made complex structures of atmospheric layers, as the cold air and systematic winds weakened in the end of a cold air event. Weakened wind shears and inversion layers, especially a strong near-surface inversion layer, remarkably diminished the atmospheric diffusion abilities and facilitated an especially high concentration of surface aerosols. The convergence line or weak shear line of sea breeze in the ground level helps weaken the atmospheric diffusion abilities and results in atmospheric aerosols accumulation. 相似文献
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对“抖音”、“快手”、“微信视频号”等短视频平台特征进行比对,探究各个平台之间的内在联系、运营特征与优势互补。通过分析“广东天气”头条号短视频运营服务效果,将气象核心资源产品与各短视频平台特点相结合,提供气象类短视频产品的取材建议并探讨相应的分发策略:高影响天气过程相关的预报、预警、实况、科普短视频产品关注度高,建议发布于“抖音”和微信视频号;气象题材的深度解读类短视频内容具有一定垂直深度,建议发布于头条号(西瓜视频)和B站;各类美景和灾害天气实景短视频易引起用户共鸣,建议发布于“抖音”、快手和微信视频号;常规天气预报短视频建议发布于头条号及微信视频号。 相似文献
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南岭山地一次锋面浓雾过程的边界层结构分析 总被引:11,自引:1,他引:11
利用2001年3月上旬在南岭山地进行的综合野外观测资料,分析了有雾和无雾时的天气型和边界层风、温、湿结构特征。分析表明,冷空气影响期间出现的地面雾是低空湿度饱和区向地面扩展,云底接地形成的雾,锋面雾消散过程实质上为雾层底逐渐抬升离开地面的过程。边界层结构受天气系统的影响,锋面逆温结构对雾的维持有重要作用,单层强逆温结构有利于雾的发展和维持,多层(双层)弱逆温结构容易导致雾消散;出现雾与前期低空南风强劲,高空盛行西南或西南西气流,充分回暖增湿,导致整层空气湿度大有密切关系;浓雾维持期间,出现小到中雨时,雨强峰值时间段都出现能见度短时好转的现象,否则则反之,表明云雾中的微物理过程与能见度有密切关系。 相似文献
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香港地区空气污染的典型天气背景形势 总被引:8,自引:0,他引:8
利用香港地区2000~2005年共6年每小时一次的空气污染指数(API)资料和NCEP/NCAR 2.5 °×2.5 °风场、气压场再分析资料分析了香港地区空气污染指数特征以及典型天气形势对香港地区空气污染的影响.结果表明:近几年,香港地区空气污染日逐年增加,空气污染指数有明显的季节变化,大部分监测站空气污染日出现次数最多的是1~3月,其次是7~9月,出现次数最少是在4~6月;造成香港地区空气污染典型的天气形势有热带气旋型、大陆冷高压型、入海变性高压型和低压槽型四类. 相似文献
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With the hourly data of Air Pollution Index (API) by Hong Kong Environmental Protection
Department (HKEPD) during the 6 years of 2000 - 2005 and NCEP / NCAR reanalysis data of 2.5° ×
2.5° wind and pressure fields, the characteristics of API in Hong Kong area and the impacts of typical
weather characteristics on the air pollution in Hong Kong have been studied. The results are shown as
follows. (1) The API exhibits obvious seasonal variability as the number of air pollution days increases by
the year. For most of the local monitoring stations, it is the most from January to March, a little less from
July to September and the least from April to June. (2) There are four typical types of weather situations
that are responsible for the air pollution in Hong Kong: tropical cyclones, continental cold highs,
transformed highs that have moved out to sea and low pressure troughs. 相似文献
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飞机起降过程污染物排放对机场周边大气环境影响研究回顾与进展 总被引:1,自引:0,他引:1
航空运输业的飞速发展引起了人们对飞机场污染物排放的关注。飞机污染物的排放过程主要包括起降过程和巡航过程。目前对机场飞机排放污染物的研究主要集中在飞机的起降过程(LTO循环过程),研究手段主要为模型分析,如EDMS模型分析、SMOKE/CMAQ模型分析等,只有少量的实地采样研究。未来的研究需更细化,增加实地采样,开展定量的分析研究。 相似文献