Variation of black carbon in Northeast China based on ground observation and MERRA-2 reanalysis data

Qingli Song, Yanan Li, Dajiang Yu, Jinrong Zhao, Zhou Li, Yong Zhang, C.-H. Weng, R. Weerasinghe, J. Wu
2020 E3S Web of Conferences  
The temporal variations of black carbon concentration at 7 sites, including Longfengshan, Anshan, Benxi, Dalian, Changchun, Shenyang, and Fushun, in Northeast China was studied based on up to 11 years of ground observations and MERRA-2 reanalysis dataset. Except for Benxi, Changchun and Shenyang, at other four sites, the ground-based black carbon concentrations have decreased generally in the last decade, while changes in the black carbon concentration of MERRA-2 are relatively small. The
more » ... ly small. The seasonality of measured black carbon concentration shows a trend of low in May-June and high in January at all sites, and the diurnal cycles present similar pattern with two peaks occurring at 10:00-12:00 UTC and 23:00-24:00 UTC respectively, two troughs occurring at 05:00-07:00 UTC and 19:00-20:00 UTC respectively. The daily mean of MERRA-2 black carbon concentration is 49.3% lower than that of the ground observations at 7 sites averagely. They also show poor consistency in terms of seasonal and daily changes, which perhaps means an inappropriate application of MERRA-2 black carbon concentration at single point in Northeast China.
doi:10.1051/e3sconf/202019404061 fatcat:lrxj75i3vfh5vn7vedafj6tgwe