基于TROPOMI数据分析四川盆地NO_(2)排放特征

Characterization of NO_(2)Emissions in the Sichuan Basin based on TROPOMI Data

基于TROPOMI NO_(2)对流层垂直柱浓度卫星数据针对2019年四川盆地区域对流层NO_(2)柱浓度的时空演变特征进行了分析,并结合高分辨率排放清单和WRF-CMAQ模型对四川盆地NO_(x)排放清单的不确定性进行了初步评估。结果表明,2019年四川盆地对流层NO_(2)柱浓度高值区主要集中在成都平原,川南城市群和重庆市等人为源活动强烈的地区,盆地中部地区则相对清洁。受气象条件和人为源排放的共同影响,四川盆地冬季和春季的NO_(2)柱浓度明显高于夏季和秋季。对比高分辨率WRF-CMAQ模型模拟的1月NO_(2)柱浓度与TROPOMI反演的1月NO_(2)柱浓度,TROPOMI观测的对流层NO_(2)柱浓度在川东北城市群等清洁地区与CMAQ模型具有高度一致性,但对成都市和重庆市等高人为源排放的城市则表现为明显高于CMAQ模拟柱浓度,表明人为源清单能较好地反映中型城市和经济欠发展地区NO_(2)排放特征但对特大城市的NO_(2)排放可能存在低估。综合分析结果表明,在下一阶段应在严格控制特大城市(成都市和重庆市)NO_(x)排放量的同时加强对四川盆地中型城市的NO_(x)排放控制。

This study utilizes a high-resolution emission inventory and the WRF-CMAQ modeling system to analyze the temporal and spatial evolution of tropospheric NO_(2)vertical column density(VCD)derived from TROPOMI satellite data.It also provides a preliminary assessment of the uncertainty in the NO_(x)emission inventory for the Sichuan Basin in 2019.The findings reveal elevated tropospheric NO_(2)VCD in areas with intense anthropogenic activity,including the Chengdu Plain,southern Sichuan's urban clusters,and Chongqing,while the central Sichuan Basin remains relatively clean.Seasonal variations,influenced by both meteorological conditions and anthropogenic emissions,show significantly higher NO_(2)VCD in winter and spring compared to summer and autumn.A comparison between the WRF-CMAQ model and TROPOMI satellite data for January 2019 indicates strong agreement in cleaner regions,though TROPOMI reports notably higher NO_(2)VCD in high-emission cities such as Chengdu and Chongqing,suggesting that the emission inventory may underestimate NO_(x)emissions in megacities.This work underscores the need for stringent NO_(x)emission controls in major cities,such as Chengdu and Chongqing,while also emphasizing the urgency of enhancing emission controls in medium-sized cities across the Sichuan Basin.