天津春节期间烟花爆竹燃放对空气质量的影响

为明晰春节期间烟花爆竹燃放对大气环境的影响，利用天津地区2016年和2017年春节期间（除夕至农历十五，公历2016年2月7-22日、2017年1月27日-2月11日）大气污染物质量浓度的监测数据和气象观测资料，对这一时期大气污染物质量浓度的变化规律进行分析.结果表明:天津春节期间大气颗粒物质量浓度峰值均出现在初一的00:00-01:00.烟花爆竹燃放对ρ（PM₁₀）、ρ（PM_2.5）和ρ（SO₂）影响较大，尤其是对地面污染物质量浓度影响最大，并且对ρ（PM_2.5）和ρ（PM₁₀）的影响高度相对增高，但对ρ（NO₂）的实时影响最小.初一00:00-00:01，ρ（PM₁₀）、ρ（PM_2.5）、ρ（SO₂）和ρ（NO₂）分别增加了305、178、80和7 μg/m3.烟花爆竹燃放使ρ（PM_2.5）和ρ（PM₁₀）的日变化曲线较非春节期间波动性增强，主峰值区（20:00-翌日01:00）污染物质量浓度升高和出现的时间延后；ρ（SO₂）主峰值出现时段由09:00-10:00变为00:00左右，并且其峰值剧增.烟花爆竹燃放使夜间空气中ρ（PM_2.5）上升，导致ρ（PM_2.5）在ρ（PM₁₀）的占比显著升高.2016年和2017年春节期间，PM_2.5、PM₁₀和SO₂的最大小时质量浓度及其变化率均高于春节前后（除夕前15 d和农历十五后15 d），而NO₂和CO的最大小时质量浓度及其变化率则低于春节前后.2016年和2017年除夕ρ（PM_2.5）的半衰期分别为4.7和3.6 h.研究显示，即使在有利于扩散的气象条件下，烟花爆竹燃放仍可使天津地区ρ（PM₁₀）、ρ（PM_2.5）和ρ（SO₂）短时迅速增大，污染物质量浓度主峰值均出现在夜间，ρ（PM_2.5）的半衰期介于3~5 h. 

Impacts of Fireworks on Air Pollution during the Spring Festival in Tianjin City

With the pollutants monitoring data and meteorological data during the Spring Festival in Tianjin City in 2016 and 2017, the variation characteristics of atmospheric pollutant concentration and the influence of fireworks on atmospheric pollution were investigated. The results indicated that the peak concentration of atmospheric particulate matter during the Spring Festival appeared from 00:00 to 01:00 on the first day of New Year. Fireworks had a greater impact on the concentration of particulate matter and SO₂ than the other pollutants, especially for the ground concentration. The influence on particulate concentration was relatively high. The concentrations of PM₁₀, PM_2.5, SO₂ and NO₂ increased by 305, 178, 80 and 7 μg/m3 from 00:00 to 01:00. The daily variations of PM_2.5 and PM₁₀ concentrations were greater during the Spring Festival than during non-festival because of fireworks. The peak concentration of pollutants in the main peak period (20:00 to 01:00 of next day) was increased and delayed. The main peak period of SO₂ changed from morning (09:00-10:00) to about 00:00, and the peak concentration increased dramatically. The discharge of fireworks resulted in an increase in the concentration of fine particles in the air. The proportion of PM_2.5 in PM₁₀ increased significantly, and the main influencing period was at night. The maximum hourly concentration and its change rate of PM_2.5, PM₁₀ and SO₂ during the Spring Festival were higher than that before and after the Spring Festival, while the maximum hourly concentration and the variability of NO₂ and CO concentrations were lower than that before and after the Spring Festival. The half-lives of PM_2.5 on Chinese New Year's Eve in 2016 and 2017 were 4.7 and 3.6 h. The results show that fireworks and firecrackers can make the concentrations of PM₁₀, PM_2.5 and SO₂ increase rapidly for a short time even in the meteorological conditions conducive to diffusion. The main peak value of mass concentration appeared at night, and the half-life of PM_2.5 concentration is between 3 and 5 h.