The community emissions data system is a software system developed for research use, using the R open source programing language that produces consistent estimates of global air emission species over the industrial era (1750- latest full year) by country, sector, and fuel. The system focuses on aerosol and aerosol precursor emissions, e.g. emissions that impact atmospheric chemistry and aerosol loadings. Emissions are also mapped to spatial grids, produced in netCDF format, for use by Earth system and other atmospheric models. Data inputs to this system include emission inventories and driver data, such as energy consumption and population estimates, and default emission factors, which are used together to produce consistent estimates of emissions over time. The data system is unique in its blending of emission data from multiple sources together with driver data, to consistently estimate emission trends over time in an open source framework. This software was planned, from original conception and in the project proposal and FWP, to be released as open-source software.