冬季采暖优化对北京地区空气质量的影响

空气污染能够影响人体健康、交通运输、农业生产等，会对国家经济造成损失。多年来，北京一直是空气污染严重地区，而冬季燃煤采暖是一个重要的原因。2016～2017年，北京大力优化采暖的能源结构，旨在改善空气质量。本文通过分析5个位于北京不同区域的空气质量监测站的PM2.5、PM10、SO₂、NO₂和CO污染物浓度，对比了2018年和2015年的空气质量变化情况。结果显示:2018年5个站5种污染物浓度较2015均下降，平均下降幅度为37.3%，而5个站降幅最大的污染物浓度都是SO₂，平均降幅为59.2%。进一步分析表明，两年5种污染物浓度的差距主要来自冬季的取暖时期。2018年冬季5个站重空气污染（PM2.5浓度>150 μg/m3）天数较2015年平均下降率高达91.3%，比其他季节多了41.3%。相较于2015年，5个站平均的2018年冬季5种污染物浓度平均下降值是其他季节的4.8倍，平均下降的幅度是其他季节的2.3倍。逐小时数据分析显示，2018年较2015年冬季污染物浓度下降比较大的时刻主要来来自暖更多的时间段。结合气象条件分析表明，北京冬季采暖优化很大程度地提高了空气质量，这为有相似采暖方式的城市的空气污染治理提供借鉴和参考。

Impacts of Clean-Energy Heating Transformation in Winter on the Air Quality in Beijing

Air pollution can exert significant impacts on human health, transportation, agriculture, and etc., thereby causing huge losses in the economy. For many years, air pollution has been severe in Beijing, and coal heating is a major contributor. During 2016–2017, a clean heating-supply transformation was performed to improve the air quality in Beijing. This study compares the different concentrations of particulate matter (PM), PM2.5, PM10, O₃, SO₂, NO₂, and CO, in 2018 to those in 2015 at five stations located in different districts of Beijing to evaluate the role of clean energy heating transformation in improving the air quality. Results show that the concentrations of PM2.5, PM10, SO₂, NO₂, and CO in 2018 all reduced compared with those in 2015, and the averaged reduction is 37.3%, with SO₂ concentration decreasing the most, that is, by 59.2%. Further analysis reveals that the difference in pollutant concentrations between 2018 and 2015 mainly occurs in winter when people use a heating supply. Compared with 2015, the number of heavily polluted days (PM2.5concentration> 150 μg/m3) declined in winter by 91.3% on average and more than 41.3% in other seasons. The averaged difference between the winters of 2018 and 2015 in PM2.5, PM10, SO₂, NO₂, and CO concentrations is 4.8 times that of other seasons with 2.3 times the reduction percentage. Analysis from hourly data demonstrates that a relatively larger decrease mainly occurred at times when much more heating is used. Combined with meteorological conditions, these results imply that the clean energy heating transformation largely improves the air quality, providing a reference for other cities with a similar heating supply.