摘 要

二氧化氮（NO₂）是一种重要的痕量气体，也是主要的大气污染气体，主要分布在对流层和平流层中，是臭氧、酸雨等环境污染现象的的重要前体物之一。如今，NO₂的浓度含量已经成为评价大气污染水平的重要指标。臭氧监测仪（OMI）是专门用于监测大气中的气溶胶、云和大气主要痕量气体浓度的仪器，搭载于2004年发射的地球观测卫星（Aura）上。本文研究的华中地区包括河南省、湖南省和湖北省三个省份，此区域中人口数量大，社会经济发展快，人类活动密集，大气污染比较严重。本研究以华中地区作为研究对象，使用 Matlab和IDL等技术平台，对OMI遥感数据进行处理，得到华中地区对流层NO₂柱浓度的有效均值，分析2008-2017这十年间华中地区对流层NO₂垂直柱浓度的时空分布格局和变化趋势，并且从自然和人为两方面探讨NO₂浓度的影响因素。

研究发现，在研究时间尺度内，华中地区对流层NO₂垂直柱浓度呈现先增加后降低的趋势，并且具有明显的季节周期性，其中，秋季和冬季对流层NO₂柱浓度偏高，最高值一般出现在12月和1月；春季和夏季NO₂浓度值较低，一般在7月和8月出现最低值，总体呈现出夏季lt;春季lt;秋季lt;冬季的情况。在地理分布上，华中地区中东部地区的NO₂柱浓度明显高于西部地区，并且河南省NO₂污染程度明显比湖南和湖北两省严重。不同省份对流层NO₂柱浓度比较显示，在研究时间尺度内，NO₂浓度呈现先增加后减少的趋势，各省份在秋冬季节NO₂浓度值较大，春夏两季较小，这与华中地区NO₂柱浓度变化趋势一致，不同季节NO₂柱浓度变化差异显著。通过研究对流层NO₂柱浓度的影响因素发现，地形特征、年均温和年降水量、人口密集程度和区域经济发展情况和NO₂浓度密切相关，民用车辆拥有量与NO₂浓度呈现负相关，这可能与在研究时间尺度内科技发展以及各地采取了大量的节能减排措施有关。

关键词：OMI；对流层NO₂垂直柱浓度；华中地区；时空分布特征；影响因素

Abstract

Nitrogen dioxide (NO₂) is a major pollution gas and an important trace gas, mainly distributed in the troposphere and stratosphere. It is one of the important precursors of environmental pollution phenomena such as ozone and acid rain. Nowadays, the concentration of NO₂ has become an important index to evaluate the level of air pollution. The Ozone Monitoring Instrument (OMI) is an instrument used by the Earth Observation Satellite (Aura) is an instrument designed to monitor the concentration of aerosols, clouds and major trace gases in the atmosphere. It was launched on the Earth Observation Satellite (Aura) in 2004. Central China studied in this paper includes three provinces, Henan, Hunan and Hubei, with a large population, intensive human activities, rapid social and economic development, and then serious air pollution. This paper uses OMI NO₂ column densities data, under the support of MATLAB and IDL, to analyze the central China during 2008-2017 tropospheric NO₂ column concentration on the space-time distribution characteristics, and from two aspects of natural and man-made, to discuss the influence factors of NO₂ concentration.

The study found that, within the time scale of the study, the vertical column concentration of tropospheric NO₂ in Central China showed a trend of increasing at first and then decreasing, at the same time, it showed obvious seasonal changes. The concentration of tropospheric NO₂ column was the highest in winter, and the highest value generally appeared in December and January. The NO₂ concentration value is the lowest in summer, which generally occurs in July and August, and generally presents the situation of summer lt; spring lt; autumn lt; winter. In terms of geographical distribution, the concentration of NO₂ column in the central and eastern regions of central China was significantly higher than that in the western regions, and the pollution level of NO₂ in Henan province was significantly higher than that in Hunan and Hubei provinces. The comparison of NO₂ column concentration in troposphere in different provinces showed that, in the study time scale, NO₂ concentration showed a trend of increasing first and then decreasing, too. The NO₂ concentration in each province was larger in autumn and winter and smaller in spring and summer, which was consistent with the variation trend of NO₂ column concentration in central China. The variation of NO₂ column concentration in different seasons was significantly different. Through the troposphere the factors affecting the concentration of NO₂ column found, topography, moderate average annual precipitation, intensive population and regional economic development and is closely related to the concentration of NO₂. Civilian vehicles ownership is negatively related to the NO₂ concentration , it is probably related to the development of science and technology and the adoption of a large number of energy conservation and emission reduction measures.

Key words: OMI, Tropospheric NO₂ vertical column density, Central China, Spatial and temporal distribution characteristics, influencing factors

目录

第1章 绪论 1

1.1研究背景与意义 1

1.1.1研究背景 1

1.1.2痕量气体 1

1.1.3 NO₂介绍 2

1.2 NO₂观测方法 3

1.2.1地面观测 3

1.2.2卫星大气探测 3

1.2.3大气NO₂遥感监测进展 3

1.3研究内容及研究意义 4

第2章 研究区概况 6

2.1自然地理概况 6

2.2经济与社会发展状况 6

2.2.1人口发展现状 6

2.2.2经济发展现状 7

第3章 数据来源及数据处理 9

3.1数据来源 9

3.1.1臭氧层观测仪（OMI） 9

3.1.2 OMNO2d产品 9

3.2数据处理 10

3.2.1预处理 10

3.2.2 分析方法 10

第4章 结果与分析 11

4.1华总地区NO₂柱浓度空间分布特征 11

4.1.1年变化特征 11

4.1.2季节变化特征 12

4.2华中地区NO₂柱浓度时间分布特征 16

4.2.1年变化趋势 16

4.2.2季节变化趋势 17

4.2.3月变化趋势 19

第5章 对流层NO₂垂直柱浓度的影响因素 23

5.1自然因素 23

5.1.1地形特征 23

5.1.2年降水量 23

5.1.3年均温 23

5.2社会因素 24

5.2.1人口密度与社会经济发展状况 24

5.2.1民用车辆拥有量 25

第6章 结论与讨论 26

6.1主要结论 26

6.1.1华中地区对流层NO₂柱浓度空间变化特征 26

6.1.2华中地区对流层NO₂柱浓度时间变化特征 26

6.1.3影响华中地区对流层NO₂柱浓度时空分布的因素 27

6.2不足之处 27

参考文献 28

致谢 31

第1章 绪论

1.1研究背景与意义

1.1.1研究背景

NO₂是存在于对流层中的一种重要痕量气体，不仅是臭氧和其他光化学次生污染物的最重要前体物之一，也是大气中的主要污染气体，能够产生酸雨、酸雾和光化学烟雾等环境污染现象^[1]。对人体健康、大气环境，生态环境和生物化学循环和等方面都可能产生极大的危害。

工业革命后，随着城市化的迅速推进，能源需求量日益增加，消耗量也不断攀升，NO₂排放量逐年上升，大气中的NO₂含量也不断升高，大气污染愈发严重，如今，研究对流层NO₂浓度的时空变化及其对环境和气象的影响已成为一大热点^[2]。