北京近郊大气混合层结构特征观测分析

发布时间：2017-12-31 14:21

本文关键词：北京近郊大气混合层结构特征观测分析　出处：《南京信息工程大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着工业化、城市化的迅速发展,人为排放到大气中的气溶胶粒子含量不断增加,霾天气频发。对人类的身体健康、气候变化和生态、环境都造成了很大的影响。目前对于灰霾发生期间大气垂直方向上污染特征的研究较少。当污染源排放确定后,大气混合层高度(MLH)对灰霾是否发生及轻重有重大影响,且灰霾的发生也能引起大气混合层高度的变化。本文采用激光雷达对河北香河大气混合层进行了近一年半时间的观测,并结合气象条件对大气混合层的日变化等进行了研究。结果表明,MLH的日变化同温度的变化、风速密切相关,相关系数达0.968和0.580。春季各个时刻的MLH明显高于秋、冬两个季节；秋冬两季混合层的发展相似,MLH较低,大体上秋季的MLH高于冬季。灰霾天较高的气溶胶含量使得它的大气温度高于非灰霾天。风速变化对灰霾天MLH的影响更大。其次,分析了观测期间MLH的月变化及季节变化特征。混合层在4、5月发展最为旺盛。10月至2月混合层发展较弱。因此,当从地面排放的气溶胶含量一定时,在4、5月份气溶胶垂直方向的扩散范围和扩散速度较快,不易形成灰霾天气。而10月至2月,混合层在垂直方向上的发展范围和速度都较小,不利于气溶胶在垂直方向上的输送,气溶胶粒子易在近地面聚集,形成灰霾天气。最后对各个季节不同程度霾天气下的MLH日变化及气象条件进行了个例分析。2006年10月30日和11月8日能见度的差异主要是由于风速造成的。2007年5月26日和3月24日的能见度是由这两天非常大的温度差异引起的。2007年2月8日和2月23日能见度有可能是由于2月8日排放到大气的总污染物过多造成的。
[Abstract]:With the rapid development of industrialization, city, anthropogenic emissions to aerosol content in the atmosphere is increasing, haze frequently. On human health, climate change and ecological environment have caused a great impact. The occurrence of haze in the atmosphere during the vertical study on pollution characteristics of pollution emissions when less. After determining the atmospheric mixing height (MLH) have a significant impact on the occurrence and severity of occurrence of haze, haze and can cause atmospheric mixed layer height changes. This paper uses the laser radar observation has been nearly a year and a half of the Hebei Xianghe atmospheric mixed layer, and combined with the meteorological conditions of the atmospheric mixed layer on the change was studied. The results show that diurnal variations of MLH with temperature and wind speed are closely related, the correlation coefficient was 0.968 and the 0.580. spring each time MLH was significantly higher than that in autumn, winter two season The development section; two seasons of autumn and winter mixed layer is similar to that of MLH is relatively low, in autumn than in winter. The content of MLH aerosol haze days high atmospheric temperature makes it higher than in non haze days. The effect of wind speed change on haze days MLH. Secondly, analyzes the changes of monthly variation and seasonal characteristics observed during MLH the mixed layer at 4,5 months. The development of the most exuberant.10 months to February mixed layer development is weak. Therefore, when a certain aerosol emissions from the ground, spread in the vertical direction of 4,5 in aerosol and spread quickly, is not easy to form haze. And from October to February, the development of mixed layer range in the vertical direction and the speed is small, is not conducive to the transport of aerosols in the vertical direction, the aerosol particles easily in the near surface aggregation of haze formation. Finally, the diurnal changes of MLH of each season in different degrees under haze weather and meteorological conditions. The difference between the case analysis of.2006 in October 30th and November 8th the visibility is mainly due to wind speed caused by the.2007 in May 26th and March 24th, the visibility is caused by these two days is very large temperature difference of.2007 in February 8th and February 23rd have visibility may be due to the February 8th total pollutant emissions to the atmosphere caused by too much.

【学位授予单位】：南京信息工程大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P412;P421.3;X51

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