Analysis of Recent Anthropogenic Surface Emissions from Inventories and Inverse Modelling Estimates: Are Future Emission Scenarios Valid for the Recent Past?

In this study, we compare current state-of-the-art global and regional emission inventories to several recent top-down inverse modeling satellite estimates of various chemical species (CO, NOx, NMVOC, BC, and OC) in different world regions. Specifically, bottom-up inventories such as the CEDS (Community Emissions Data System) inventory which provides historical emissions for the IPCC AR6 report, the CAMS-GLOB-ANT inventory developed as part of the Copernicus Atmosphere Monitoring Service (CAMS) on the basis for CEDS and EDGARv4.3, and the MACCity inventory developed previously within the Monitoring Atmospheric Composition and Climate(MACC) project are compared to top-down estimates, such as Zheng et al. (2019), Chen et al. (2018), Ding et al (2017) and Miyazaki et al (2019), which use inverse modeling methods and various spaceborne chemical observations to constrain surface emissions. Regional inventories for Europe (CAMS-REG-AP, Granier et al. 2019), Africa (DACCIWA, https://www.eccad3.sedoo.fr) and China (MEICv1.3: http://www.meicmodel.org) are also included in the analysis. In addition, the emission estimates over the last few years are compared to the five Shared Socioeconomic Pathways (SSPs), which provide a range of scenarios that examine how global society might change over the century. For each region, the SSP lying closest to recent trends is identified. This analysis allows to evaluate the current emission estimates and trends, bring into light differences and possible inconcistencies, and provide useful guidance in selecting the scenarios to be downscaled for particular regions for air quality and climate projections and regional impact studies (e.g. CORDEX, http://www.cordex.org).