中国高分辨率近地面NO2浓度反演

通过分析2010年全国333个县级以上城市卫星遥感的NO2对流层年均柱浓度与地面实际观测浓度之间的相关性,发现两者具有一定的线性相关性(r=0.54,n=333),并建立了NO2"遥感柱浓度"与"地面观测浓度"之间的关联方程,通过该方程反演了中国0.125°分辨率近地面NO2污染分布特征。结果表明,全国近地面NO2浓度超过《环境空气质量标准》(GB 3095—2012)要求的年均浓度二级标准(0.04 mg/m3)的区域约为5.95万平方千米,超标地区主要集中在华北平原、长三角地区、四川盆地和珠三角地区,这些地区NO2污染水平远高于333个城市的年平均值(0.028 mg/m3)。NO2污染极不平衡,以大中型城市为中心的区域污染特征显著。NO2人口加权浓度分析结果表明,NO2人口加权浓度高值区主要集中在能源消费量大、机动车保有量大及人口密集的地区,全国约5.7%的人口暴露在NO2超标区域。

Retrieval of NO2 Concentrations in High Resolution Near-surface in China

By analyzing annual average concentrations of NO₂ tropospheric column density from satellite remote sensing and ground concentrations of NO₂ in 333 cities above county level in 2010, this study found there was a linear correlation(r=0.54,n=333) between them, the correlation equation was established, the 0.125 degree NO₂ distributions near-surface were obtained. The results showed that: the area was about 59,500 square kilometers where NO₂ concentration was greater than the national secondary limit 0.04mg/m³, mainly in the North China Plain, the Yangtze River Delta, Pearl River Delta and the Sichuan Basin; NO₂ concentrations in these areas were much higher than the average value 0.028mg/m³ of 333 cities. The heavy pollution distributions were extremely uneven, it is mainly located in metropolis and medium-sized cities. The NO₂ population-weighted concentration analysis showed that high value is mainly concentrated in metropolis and medium-sized cities with more energy consumptions, more vehicles and higher population density; approximately 5.7% of the population were exposed to the atmosphere where NO₂ concentration was over 0.04 mg/m³.