A very high-resolution (1km??1 km) global fossil fuel CO2 emission inventory derived using a point source database and satellite observations of nighttime lights
Emissions of CO2 from fossil fuel combustion are a critical quantity that must be accurately given in es- tablished flux inversion frameworks. Work with emerging satellite-based inversions requires spatiotemporally-detailed inventories that permit analysis of regional natural sources and sinks. Conventional approaches for disaggregating na- tional emissions beyond the country and city levels based on population distribution have certain difficulties in their appli- cation. We developed a global 1km×1km annual fossil fuel CO2 emission inventory for the years 1980–2007 by com- bining a worldwide point source database and satellite obser- vations of the global nightlight distribution. In addition to estimating the national emissions using global energy con- sumption statistics, emissions from point sources were es- timated separately and were spatially allocated to exact lo- cations indicated by the point source database. Emissions from other sources were distributed using a special night- light dataset that had fewer saturated pixels compared with regular nightlight datasets. The resulting spatial distributions differed in several ways from those derived using conven- tional population-based approaches. Because of the inherent characteristics of the nightlight distribution, source regions corresponding to human settlements and land transportation were well articulated. Our distributions showed good agree- mentwith a high-resolution inventory across the US at spatial resolutions that were adequate for regional flux inversions. The inventory can be extended to the future using updated data, and is expected to be incorporated into models for op- erational flux inversions that use observational data from the Japanese Greenhouse Gases Observing SATellite (GOSAT).