Liu Fei, Beirle Steffen, Zhang Qiang, van der A Ronald J, Zheng Bo, Tong Dan, He Kebin
Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China.
Royal Netherlands Meteorological Institute (KNMI), P.O. Box 201, De Bilt, the Netherlands.
Atmos Chem Phys. 2017;17(15):9261-9275. doi: 10.5194/acp-17-9261-2017. Epub 2017 Aug 1.
Satellite NO observations have been widely used to evaluate emission changes. To determine trends in NO emission over China, we used a method independent of chemical transport models to quantify the NO emissions from 48 cities and 7 power plants over China, on the basis of Ozone Monitoring Instrument (OMI) NO observations during 2005 to 2015. We found that NO emissions over 48 Chinese cities increased by 52% from 2005 to 2011 and decreased by 21% from 2011 to 2015. The decrease since 2011 could be mainly attributed to emission control measures in power sector; while cities with different dominant emission sources (i.e. power, industrial and transportation sectors) showed variable emission decline timelines that corresponded to the schedules for emission control in different sectors. The time series of the derived NO emissions was consistent with the bottom-up emission inventories for all power plants (r=0.8 on average), but not for some cities (r=0.4 on average). The lack of consistency observed for cities was most probably due to the high uncertainty of bottom-up urban emissions used in this study, which were derived from downscaling the regional-based emission data to cities by using spatial distribution proxies.
卫星对一氧化氮（NO）的观测已被广泛用于评估排放变化。为了确定中国一氧化氮排放的趋势，我们采用了一种独立于化学传输模型的方法，基于2005年至2015年期间臭氧监测仪器（OMI）对一氧化氮的观测，对中国48个城市和7个发电厂的一氧化氮排放进行量化。我们发现，从2005年到2011年，中国48个城市的一氧化氮排放量增加了52%，而从2011年到2015年则下降了21%。2011年以来的下降主要归因于电力部门的排放控制措施；而具有不同主要排放源（即电力、工业和交通部门）的城市，其排放下降时间线各不相同，这与不同部门的排放控制时间表相对应。推导得出的一氧化氮排放时间序列与所有发电厂的自下而上排放清单一致（平均r=0.8），但与一些城市的排放清单不一致（平均r=0.4）。在城市中观察到的这种不一致，很可能是由于本研究中使用的自下而上的城市排放具有高度不确定性，这些排放是通过使用空间分布代理将基于区域的排放数据下推到城市得到的。
