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2010年广州亚运限行减排对大气环境的影响 总被引:3,自引:0,他引:3
通过对亚运会、亚残运会期间限行减排各个阶段的广州和相邻城市监测到的污染物浓度以及同期的天气背景进行分析,探讨污染源、城市的地理位置、天气条件和限行减排对亚/亚残运会期间广州大气环境的影响,结果表明:由于人为限行减排、城市的地理位置和气象扩散条件等各种因素综合作用,使得亚运会期间广州统计平均的能见度基本大于10 km;机动车的限行减排对PM10的削减作用不如PM2.5和PM1明显;限行减排对广州O3浓度控制"不敏感",但是会导致浓度峰值时间相对广东东莞出现1小时左右时间"滞后";珠江三角洲(简称珠三角)的大气环境问题呈现区域性,而且污染程度不容乐观,将来对该区域的大气环境治理需要进行长期持续的联防联控。 相似文献
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概要介绍目前大气臭氧层研究的重要成果,特别强调大气臭氧层在维持气候和环境中的重要作用及其与太阳活动、大气环流和光化学过程的依赖关系 相似文献
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本文建立了一个二维定常大气中尺度数值模式,并用该模式讨论了由下垫面粗糙分布非均匀(局地动力强迫)和温度分布非均匀(局地热力强迫)而产生的局地大气环流与大气边界层湍流的相互作用。结果指出:下垫面存在温度分布非均匀时运动方程中的湍流交换项与水平气压梯项一样可促使局地热力环境的形成,由粗糙度分布非均匀强迫产生的局地环流与由下垫面温度分布非均匀强迫产和的局地热力环流间的非线笥相互作用是通过湍流交换实现的。 相似文献
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影响上海市空气质量的地面天气类型及气象要素分析 总被引:22,自引:0,他引:22
地面天气形势及气象要素的变化在空气污染潜势预报中具有很好的指示作用。利用天气学原理将地面天气系统进行分型,探索研究不同地面天气类型对上海空气质量变化的影响。整理、分析2003—2005年地面天气类型和气象要素与空气质量的关系,发现:(1)上海秋冬季以大陆冷性高压系统移动为主,而夏季主要以副热带高压和台风影响为主,春季是冬季与夏季之间的过渡,天气系统转换较为频繁。(2)春、秋、冬季易引起上海市空气污染的天气类型有L型高压、高压、高压前和均压场4种地面天气类型,与空气质量优等级相对应的天气类型是低压槽、高压底和高压后。夏季空气质量优等级对应的天气类型主要有台风、高压(副高)和低压槽。(3)秋冬季节典型天气过程一般经历高压前(或冷空气)→L型高压→高压→高压后(或高压底)→低压槽的转换,PM10浓度变化也表现为先升后降。(4)气象要素的变化也与空气污染存在密切联系,气压与空气污染物的关系为正相关,而气温、相对湿度和风速与空气污染物浓度呈负相关。 相似文献
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There has been a lot of discussion about the atmospheric heat source over the Tibetan Plateau (TP) and the low-frequency oscillation of atmospheric circulation. However, the research on low-frequency oscillation of heat source over TP and its impact on atmospheric circulation are not fully carried out. By using the vertically integrated apparent heat source which is calculated by the derivation method, main oscillation periods and propagation features of the summer apparent heat source over the eastern TP (Q1ETP) are diagnosed and analyzed from 1981 to 2000. The results are as follows: (1) Summer Q1ETP has two significant oscillation periods: one is 10-20d (BWO, Quasi-Biweekly Oscillation) and the other is 30-60d (LFO, Low-frequency Oscillation). (2) A significant correlation is found between Q1ETP and rainfall over the eastern TP in 1985 and 1992, showing that the low-frequency oscillation of heat source is likely to be stimulated by oscillation of latent heat. (3) The oscillation of heat source on the plateau mainly generates locally but sometimes originates from elsewhere. The BWO of Q1ETP mainly exhibits stationary wave, sometimes moves out (mainly eastward), and has a close relationship with the BWO from the Bay of Bengal. Showing the same characteristics as BWO, the LFO mainly shows local oscillation, occasionally propagates (mainly westward), and connects with the LFO from East China. In summary, more attention should be paid to the study on BWO of Q1ETP. 相似文献
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ANALYSIS ON CHARACTERISTICS OF ATMOSPHERIC DUCT AND ITS EFFECTS ON THE PROPAGATION OF ELECTROMAGNETIC WAVE 总被引:1,自引:0,他引:1
On the basis of introducing the basic categories of atmospheric refraction and their existingconditions,the forming processes of three kinds of atmospheric ducts are expounded.Several maincharacteristics of atmospheric duct are summarized and analyzed,and field sounding data from theWEstern North-Pacific cloud-radiation EXperiment(WENPEX)and meteorological data aroundthe Xisha sea area are used to validate these characteristics.Meanwhile the sensitivities of theevaporation duct height to the variations of atmospheric humidity.the air-sea temperaturedifference.and horizontal wind speed are examined.With the analysis of the effect of atmosphericduct on the propagation of electromagnetic wave.the maximum trapped-wavelength and the criticalemitting angle of elevation for electromagnetic wave which can form duct propagation are derived.At the same time the four kinds of necessary conditions for electromagnetic wave to form ductpropagation are brought forward.The effects of atmospheric duct on ultrashort wave propagation,radar observation.short wave communication etc.are also discussed. 相似文献
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广州空气污染指数特征及其与地面气压型的关系 总被引:6,自引:5,他引:6
根据1950~2000年50多年的降水资料,用Z指数作为旱涝等级划分标准,把雨涝情况划分成4个等级,并在此基础上计算了雨涝发生的范围。通过研究雨涝范围覆盖率变化趋势和特征,诊断我国华南雨涝发生发展趋势和变化程度。研究发现我国华南地区近50年来雨涝覆盖范围有轻微的下降趋势并具有明显的年代际变化特征;冬半年雨涝覆盖范围有较大的增长趋势,特别是1990年代以来这种趋势更强烈;夏半年雨涝范围趋于减少,呈下降态势,但夏季的雨涝范围在扩大,特别是1990年代以来,夏季雨涝范围扩大的趋势较为明显;前汛期雨涝范围有减少的趋势,而后汛期雨涝范围有明显的扩大趋势。 相似文献
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雹块微物理和雹云单体关系的初步探讨 总被引:1,自引:0,他引:1
雹块微结构中包含着有关雹块在云内生长情况和雹云本身的某些信息。它们之间的关系有些已被认识,更多的还没有被人们所认识。 为揭示雹块微物理和雹云单体的相互关系,1982年夏天我们在新疆昭苏地区开展了雹块微结构和雹云宏观特征的配合探测,取得了一定数量资料。本文根据同年7月4个降雹日(7日、13日、16日、19日)的雷达回波和500多个冰雹切片资料,着重分析了冰雹的胚胎类型,提出了比较细微的雹胚分类标准;并在这个基础上,研究了雹胚类型统计特征和雹云单体的关系,发现复合单体和弱单体的雹胚类型分布有着较明显的差别。 相似文献
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ANALYSIS ON CHARACTERISTICS OF ATMOSPHERIC DUCT AND ITS EFFECTS ON THE PROPAGATION OF ELECTROMAGNETIC WAVE* 下载免费PDF全文
YAO Zhanyu ZHAO Bolin LI Wanbiao ZHU Yuanjing DU Jinlin DAI Fushan 《Acta Meteorologica Sinica》2001,15(2):233-248
On the basis of introducing the basic categories of atmospheric refraction and their existing conditions,the forming processes of three kinds of atmospheric ducts are expounded.Several main characteristics of atmospheric duct are summarized and analyzed,and field sounding data from the WEstern North-Pacific cloud-radiation EXperiment(WENPEX) and meteorological data around the Xisha sea area are used to validate these characteristics.Meanwhile the sensitivities of the evaporation duct height to the variations of atmospheric humidity.the air-sea temperature difference.and horizontal wind speed are examined.With the analysis of the effect of atmosphericduct on the propagation of electromagnetic wave.the maximum trapped-wavelength and the critical emitting angle of elevation for electromagnetic wave which can form duct propagation are derived.At the same time the four kinds of necessary conditions for electromagnetic wave to form ductpropagation are brought forward.The effects of atmospheric duct on ultrashort wave propagation,radar observation.short wave communication etc.are also discussed. 相似文献
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AN ATMOSPHERIC MOTION EQUATION BUILT ON THE CONSERVATIVE RELATIONSHIP OF THE ANGULAR MOMENTUM EXCHANGE BETWEEN THE SOLID EARTH AND THE ATMOSPHERE ON SEASONAL-ANNUAL TIMESCALE 下载免费PDF全文
Within the seasonal-annual timeseale,there exists an angular momentum conservative exchange relationship be-tween the solid earth and the atmosphere,and their angular momentum exchange not only can cause variations inlength-of-day(LOD)but also can express anomalies in atmospheric general circulation.Therefore,their angular mo-mentum exchange mechanism should be introduced into the general circulation model.Considering the angular momentum anomalous exchange caused by the air-earth interface friction effect,awhole-layer atmospheric motion equation is derived in this paper including the earth spin anomalous friction forceparameterized by using the change in the earth rotation rate.Through analysing the equation,it shows that the magni-tude of the earth spin anomalous friction force is the same as that of Coriolis force on seasonal-annual timescale. 相似文献
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珠江三角洲东部低层大气流动与中尺度扩散特性 总被引:6,自引:0,他引:6
采用拉格朗日随机粒子扩散模式和三维风场诊断模式及实际气象观测资料,模拟分析以大亚湾核电厂厂址为中心的珠江三角洲东部地区低层大气流动和气载污染物的中尺度扩散情况。结果表明:(1)该区域低层大气流动受盛行风背景、天气系统、海陆风局地环流以及当地地形扰动的共同作用,季节变化明显。(2)冬-春-秋季,核电厂扩散的可能影响区域总体分布在偏北内陆方向和西南方的珠江出海口及外海地区,夏季总体分布于北方内陆地区。(3)污染物扩散输送出200km×200 km模拟区域的平均时间约12~20 h;污染物在模拟区域内滞留24 h以上的情况,冬-春-秋季三季的出现频率为1/5左右,夏季出现较少,约占1/20的比例。 相似文献
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STUDY ON CLIMATIC CHARACTERISTICS OF CHINA-INFLUENCING TYPHOONS AND THE INTERRELATIONS BETWEEN THEM AND THEIR ENVIRONMENTAL FACTORS 总被引:2,自引:0,他引:2
Climatic characteristics of China-influencing typhoons (CIT) were analyzed in this paper. Main characteristics include: (1) CIT season is May-November, especially from July to September. (2) Frequency of the CIT shows a decreasing trend during 1951-2004, especially after the late period of the 1960s. (3)Strong CIT also shows an obvious decreasing trend. Meanwhile, there exist obvious interdecadal variations in the CIT genesis, being more southward and eastward than normal in 1960s-1970s, and more northward and westward than normal in the 1980s. In addition, the interrelations between CIT and its environmental factors show that CIT has close relationships with sea surface temperature and East Asian summer monsoon; the structure of the circulations in frequent CIT years is much different from that in infrequent CIT years. 相似文献
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在文献[1]的基础上,首次引用近代回归分析中PRESS准则最优于集法,建立大气温湿遥感最优反演方程,并用岭回归分析评价不同准则或方法所得到的最优子集,同时用实际资料进行了验证。 相似文献