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1.
利用2004～2009年秋季臭氧监测仪的3级观测资料,分析了华北及周边地区的气溶胶光学性质。结果表明:大部分区域气溶胶光学厚度(Aerosol Optical Depth,AOD)和气溶胶紫外吸收指数(Ultra Violet Aerosol Index,UVAI)平均值分别高于0.8和0.75;高气溶胶事件发生频次统计表明,AOD高值(>0.4)频发于北京及其周边地区,UVAI高值(>1.0)频发于河北中部及南部地区;华北及其周边地区绝大多数城市平均AOD和UVAI分别高于0.7和0.60,而张家口、承德和阳泉3个城市的平均AOD和UVAI值分别低于0.6和0.65。作者进一步研究了2006年10月30日的一次霾事件中气溶胶的光学性质以及其时空分布特征。结果表明,霾由华北地区输送至渤海海域,并向东北方向输送;香河地基EZlidar激光雷达的垂直观测结果进一步表明,工业和城市型气溶胶主要集中在1500m以下,其中高浓度部分集中于650m以下,平均峰值位于285m,平均消光系数达2.15km-1;CALIOP卫星观测资料结合后向轨迹分析表明,大气低层气溶胶类型以工业和城市型气溶胶为主,而高层则由于上游大气输送沙尘粒子的混入使气溶胶类型转变为污染—沙尘型。霾事件期间,香河站CE-318太阳光度计观测的AOD平均值(标准差)从背景值0.08(0.04)升高至1.17(0.14);ngstrm指数平均值(标准差)从背景值0.90(0.10)升至1.12(0.09);核模态、积聚模态和粗模态的气溶胶粒子数柱总量均增加,其中细粒子所占比例明显升高。 相似文献
2.
利用MODIS可见光通道气溶胶光学厚度的卫星遥感和523 nm波长微脉冲激光雷达 (MPL LIDAR) 对气溶胶消光系数垂直分布的观测，分析了珠江三角洲地区2003年6月一次气溶胶污染过程中气溶胶光学厚度的分布特征、气溶胶消光系数廓线的演变，认为这次污染过程是弱高压控制下的区域性污染，而香港地区污染物浓度的上升与区域性输送有直接关系，结果表明卫星和激光雷达的光学遥感方法提供了研究大气污染的可行手段。 相似文献
3.
利用美国SAGE II (Stratospheric Aerosol and Gas Experiment II)卫星最新版（6.0版）1.020 μm通道逐日气溶胶消光系数资料，得出了对流层中上层及平流层（10 km以上高度）气溶胶光学厚度的平均分布和变化特征。结果表明:气溶胶光学厚度在低纬度大，在印度洋的岛屿上空有三个高值中心，气溶胶光学厚度高值中心与对流层中上层的上升气流的高值中心相对应。与17年(1984～2000年)年平均相比，近6年（1995～2000年）孟加拉湾至青藏高原东南部上空气溶胶光学厚度明显增加；中国东部地区上空气溶胶光学厚度增加，中西部地区则减小。气溶胶光学厚度存在三个经向的增加带和两个经向的减小带。中纬度与赤道之间的布鲁尔-多普森环流（Brewer-Dobson Circulation）带来的低层大气与对流层中上层及平流层之间的气溶胶输送是导致气溶胶这种经向一致变化的主要因素。气溶胶的这种输送产生的近地面大气污染物向中上层大气输送有可能产生重要的气候变化。 相似文献
4.
利用2018年10月—2019年9月天空辐射计观测数据反演北京城区气溶胶光学特性参数,重点分析污染过程中气溶胶光学特性与气象条件的相关性。结果表明:500 nm气溶胶光学厚度在2—7月较大,最高值出现在6月,为0.71。单次散射反照率最高值出现在8月,为0.96;最低值出现在5月,为0.89。440~870 nm ?ngstr?m波长指数最高值出现在夏季,为1.11;最低值出现在春季,为0.89。统计发现污染日数仅占总日数的17%,其中62%为轻度污染;污染和清洁天气条件下PM2.5浓度分别为107.22 μg·m-3和47.16 μg·m-3,500 nm气溶胶光学厚度分别为0.85和0.49,单次散射反照率分别为0.96和0.92;冬季?ngstr?m波长指数在污染天气条件下（1.02）大于清洁天气（0.91）,春季相反。结合天空辐射计、激光雷达和气象数据分析2019年1月一次污染事件,可知低风速与高湿度等不利气象条件、气溶胶粒子的吸湿增长和二次转化、污染物局地排放及区域输送共同导致污染事件发生。 相似文献
5.
利用2010年8月30日河北省石家庄一次霾天气条件下的气溶胶飞行探测资料,分析了石家庄地区上空658—6933 m高度范围内大气气溶胶粒子平均数浓度、平均直径的垂直分布特征和9个水平飞行高度上的谱分布特征。结果表明:轻度霾天气条件下的气溶胶平均数浓度为325个/cm3,平均直径为0.169μm。在约1000 m高度以下,气溶胶平均数浓度随高度的增加呈线性减少趋势。粒径也随高度增加而减小,由0.187μm减小至0.164μm。1000 m高度以上,气溶胶平均数浓度随高度减少趋势变缓,粒子平均直径在0.167~0.171μm范围内波动。9个不同高度上的谱分布都呈单峰型,随着高度增加,谱宽变小,峰值向小尺度方向移动。后向轨迹计算分析表明:污染气团的远距离输送可能是导致大气1500 m高度层气溶胶数浓度突增的原因。 相似文献
6.
使用新一代大气化学传输模式WRF—Chem,模拟了黄山地区2008年4月26日和5月2日不同天气背景下污染气体的输送过程。结果表明：晴天条件下,污染气体的垂直输送主要是通过山谷风环流,将山底污染物垂直向山顶输送,黄山周边地区输送对光明顶污染物体积分数影响较小,气溶胶粒子的主要来源是新粒子生成;云雾天气下,污染物的垂直输送主要是通过边界层内的湍流扩散,夜间近距离输送对光明顶污染物体积分数贡献较大,气溶胶粒子的主要来源是地面输送。 相似文献
7.
《气象》2021,(9)
利用CALIPSO气溶胶垂直廓线产品和NCEP提供的FNL 1°×1°再分析数据,以清洁日为对比,统计分析了 2007—2017年霾和重度霾期间鲁中地区气溶胶的垂直分布规律,并探讨了两者之间的关系。结果表明:霾日、重度霾日的气溶胶粒子主要聚集在对流层低层2.7 km、1.5 km以下。以0.9、1.66和1.34 km为临界高度,清洁日、霾日、重度霾日的消光系数(EC)在临界高度以上呈指数递减,以下呈对数递减。霾日和重度霾日年平均体积退偏比(PDR)和色比(CR)范围分别为0.1～0.3和0.5～0.9。低层2 km以下,重度霾日以相对规则的细粒子为主;2～4 km,不规则度和尺寸都急剧增大。PDR在7 km及以下随高度逐步增加,7 km以上逐步减小。与清洁日不同,霾日CR基本随高度逐渐增大,重度霾日则在6 km以下随高度逐渐增大。污染沙尘型气溶胶对重度霾日和霾日近地面的EC贡献最大,分别为0.58 km~(-1)和0.36 km~(-1),其次是大陆污染型,分别为0.27 km~(-1)和0.20 km~(-1)。重度霾日在1.5 km及以下维持了较小的平均风速和较大的相对湿度,有利于EC的增大。霾日在较高的高度上维持了相对较小的平均风速和相对较大的相对湿度,使得气溶胶高浓度层达2.7 km。霾时近地面污染物来源为蒙古、内蒙古等地的长距离传输和周边地区的传输。重度霾时蒙古方向和河南方向的污染物传输占比更大,分别达25.26%和31.58%。重度霾对应的多层逆温比例接近50%,贴地+低悬型和贴地+高悬型逆温在其中占比最大。由于这两种逆温型在逆温层以下对应更小的出流量,大气更稳定,使得重度霾时气溶胶粒子聚集在低层。 相似文献
8.
利用2007—2014年CALIPSO Level 2气溶胶廓线产品,统计分析了华北地区气溶胶垂直分布规律,并以2013年12月发生的一次大范围霾过程为例,探讨了霾天气中气溶胶垂直变化特征。结果表明,华北地区气溶胶消光系数(σ)随高度指数衰减,年平均标高为2.48 km;1 km以下存在σ高值层,冬季较大、春季较小,年平均为0.333km~(-1)。年平均颗粒退偏振比(Particulate Deploarization Ratio,PDR)随高度递增,变化范围为0.18~0.25;PDR春季较大,夏季较小。年平均色比(Color Ratio,CR)随高度弱增加,变化范围为0.7~0.8;春季CR随高度递减,其他季节随高度递增。华北地区近地面以污染沙尘气溶胶为主;春季以沙尘为主,夏秋季以污染沙尘为主,冬季中高层以沙尘为主,低层以污染沙尘为主。霾事件中,霾日1 km以下存在消光高值层,消光系数约为清洁日三倍。霾日PDR和CR都低于清洁日,2 km以下PDR大多小于0.2,CR以0.3~0.5为主。本地烟尘与远距离输送的沙尘相混合形成的污染沙尘是本次霾过程的主要气溶胶类型。 相似文献
9.
利用CE-318太阳光度计,采用Bouguer-Lamber定律,反演郑州地区2008年气溶胶光学厚度,分析该地区气溶胶光学厚度的日变化和月变化特征,并进一步分析天气条件对气溶胶光学厚度的影响。结果表明:2008年郑州地区气溶胶光学厚度与2007年持平,波长指数有所增大。气溶胶光学厚度存在明显的季节变化,春夏高,秋冬低,最低值出现在12月,郑州地区气溶胶光学厚度主要受工业烟尘影响。工作日和非工作日气溶胶光学厚度日变化趋势存在差异,交通负荷的变化可能对气溶胶光学厚度的日变化影响较大。轻雾和霾均能引起气溶胶光学厚度的显著增大,并且轻雾对气溶胶光学厚度的影响大于霾。沙尘过程中,气溶胶光学厚度急剧增大,而后逐渐下降,并逐渐恢复到正常水平,波长指数会减小。 相似文献
10.
乔晓燕 《沙漠与绿洲气象(新疆气象)》2020,14(3):137-143
利用2016年10月~2017年2月激光云高仪资料，分析了霾、雾、轻霾、轻雾、晴空等天气后向散射强度廓线特征，通过统计各高度层后向散射强度、后向散射强度垂直梯度的概率分布，分析了多种天气的气溶胶光学特性。结果表明：雾天气后向散射强度较霾天气大，雾厚度一般不超过300m。霾天气后向散射强度随着高度的增加减小缓慢，霾的厚度大于500m。与雾和轻雾相比，霾和轻霾天气垂直梯度绝对值取小值的概率较大。雾和轻雾天气400m高度以上垂直梯度绝对值较小，400m高度以下数值较大。由于霾区内粒子分布较均匀，雾区粒子分布起伏明显，雾区内后向散射强度忽大忽小，所以雾天气垂直梯度绝对值出现大值的概率较霾天气高。 相似文献
11.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics. 相似文献
12.
Yuepeng PAN Mengna GU Yuexin HE Dianming WU Chunyan LIU Linlin SONG Shili TIAN Xuemei Lü Yang SUN Tao SONG Wendell W. WALTERS Xuejun LIU Nicholas A. MARTIN Qianqian ZHANG Yunting FANG Valerio FERRACCI Yuesi WANG 《大气科学进展》2020,37(9):933-938
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on 相似文献
13.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d. 相似文献
14.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region. 相似文献
15.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms. 相似文献
16.
《大气和海洋科学快报》2013,(4):227
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. 相似文献
17.
《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
18.
《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters （AOSL） pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
19.
20.
《大气科学进展》2014,(6)
正Aims Scope Advances in Atmospheric Sciences(AAS)is an international journal on the dynamics,physics,and chemistry of the atmosphere and ocean with papers across the full range of the atmospheric sciences,co-published bimonthly by Science Press and Springer.The journal includes Articles,Note and Correspondence,and Letters.Contributions from all over the world are welcome. 相似文献