结合地基DOAS技术修正的OMI数据NOx排放通量获取方法研究

发布时间：2018-04-22 23:28

本文选题：被动差分吸收光谱 + OMI　；参考：《中国科学技术大学》2017年硕士论文

【摘要】：随着我国工业化和城市化对化石能源的大量消耗,以及机动车保有量和城市人口数量的急剧膨胀,华北平原地区的主要城市上空NO_2浓度及增长率均保持在较高的水平,已成为全球重点监测和控制的主要研究对象。由于NO_2柱浓度变化容易受到气象等因素的影响,并不能准确的反映出区域实际的NO_2排放情况,而NO_2排放量对于区域排放变化具有更直接准确的展示,也是对各个排放源进行监测、评估以及污染识别的重要指标。目前针对于NO_2排放量和排放清单的研究,主要集中于使用卫星观测以及卫星数据结合模型的方法,而卫星观测数据容易受到云、气溶胶等因素的影响,对对流层大气污染物敏感度较低且空间分辨率较差,研究城市尺度区域的大气污染物排放情况时,上述两种方法均不能准确的反映出研究区域的排放情况,近年来,基于车载平台的被动差分光学吸收光谱技术(differentialopticalabsorption spectroscopy,DOAS)具有高空间分辨率、对近地面大气污染物更加敏感的优势,可以在一个卫星格点内获取更多的数据,本课题建立了基于车载DOAS数据修正OMI(ozone monitoring instrument)卫星数据估算NO_2寿命以及NOx排放通量的方法,并以石家庄及周边区域为研究对象,验证了本方法的有效性。(1)研究了车载DOASNO_2数据向风场投影的方法、车载DOAS数据和OMI Level2NO_2数据产品网格化的方法以及通量和寿命估算方法的推导及简化,并在此基础上建立了基于DOAS技术修正卫星数据的方法,以提高利用卫星数据估算NO_2寿命及NOx排放通量的精确性。(2)以石家庄市及其周边地区为研究目标,在基于卫星观测数据估算寿命及排放通量传统方法的基础上,评估了该修正方法对NOx排放通量的修正效果,得到观测期间研究区域的NO_2平均寿命和NOx排放通量分别4.2h和3.6h,195.8mol/s和163.8mol/s,误差分别为:49%和37%,此外,研究发现对于复合污染特征明显、污染较为严重的城市,观测时间选择在夏季且风速分布在5～15km/h范围内时拟合效果最好。本文研究表明,将车载DOAS技术修正卫星数据的方法,运用于城市尺度的NO_2寿命及NOx排放量研究中,可以弥补传统上利用卫星数据无法准确的估算出研究区域排放情况的不足,是提高估算城市NO_2寿命以及NOx排放量准确性的有效手段。
[Abstract]:With the great consumption of fossil energy by industrialization and urbanization in China, as well as the rapid expansion of vehicle ownership and urban population, the concentration and growth rate of NO_2 over the main cities in North China Plain have been maintained at a relatively high level. It has become the main research object of global monitoring and control. Because the change of NO_2 column concentration is easy to be influenced by meteorological factors, it can not accurately reflect the actual NO_2 emission in the region. However, the NO_2 emission has a more direct and accurate display for the regional emission change. It is also an important indicator for monitoring, evaluation and pollution identification of various emission sources. The current research on NO_2 emissions and emission inventories mainly focuses on the use of satellite observations and satellite data integration models, and satellite observation data are vulnerable to cloud, aerosol and other factors. The sensitivity and spatial resolution of atmospheric pollutants in troposphere are relatively low. When studying the emission of atmospheric pollutants in urban area, neither of the above two methods can accurately reflect the emission situation of the studied region. In recent years, Passive differential optical absorption spectroscopy (DOAs) based on on-board platform has the advantages of high spatial resolution, more sensitivity to near-surface air pollutants, and the ability to obtain more data within a satellite lattice. In this paper, a method of estimating NO_2 lifetime and NOx emission flux from OMI(ozone monitoring data based on on-board DOAS data is established, and Shijiazhuang and its surrounding areas are taken as research objects. The validity of this method is verified. (1) the method of vehicle DOASNO_2 data projection to wind field, the method of product gridding of vehicle DOAS data and OMI Level2NO_2 data, and the derivation and simplification of flux and life estimation method are studied. On this basis, the method of correcting satellite data based on DOAS technology is established to improve the accuracy of estimating NO_2 lifetime and NOx emission flux using satellite data. Based on the traditional methods of estimating lifetime and emission flux based on satellite observation data, the effect of the modified method on NOx emission flux is evaluated. The average lifetime of NO_2 and the emission flux of NOx in the study area during the observation period were 4.2 h and 3.6 h, respectively, with the error of 195.8 mol / s and 163.8 mol / s, respectively, with the errors of: 49% and 37%, respectively. In addition, the study found that for cities with obvious characteristics of complex pollution and serious pollution, When the observation time is chosen in summer and the wind speed distribution is in the range of 5~15km/h, the fitting effect is the best. In this paper, it is shown that the method of correcting satellite data using DOAS technology in vehicle can be used in the study of NO_2 lifetime and NOx emission on the urban scale, which can make up for the deficiency of traditional satellite data which can not accurately estimate the emission situation in the study area. It is an effective means to improve the accuracy of estimating NO_2 lifetime and NOx emissions in cities.
【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X51

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