Quantification of space/time explicit fossil fuel CO2 emissions in urban domes

Quantification of fossil fuel CO₂ emissions from the bottom-up perspective is a critical element in emerging plans on a carbon monitoring system (CMS). A space/time explicit emissions data product can act as both a verification and planning system. It can verify atmospheric CO₂ measurements (in situ and remote) and offer detailed mitigation information to local management authorities in order to optimize the mix of mitigation efforts. Here, we present the Hestia Project, an effort aimed at building a high resolution (eg. building and road link-specific, hourly) fossil fuel CO₂ emissions data products for the urban domain. A complete data product has been built for the city of Indianapolis and work is ongoing for the city of Los Angeles. The effort in Indianapolis is now part of a larger effort aimed at a convergent top-down/bottom-up assessment of greenhouse gas emissions, called INFLUX. Our urban-level quantification relies on a mixture of data and modeling structures. We start with the sector-specific Vulcan Project estimate at the mix of geocoded and county-wide levels. The Hestia aim is to distribute the Vulcan result in space and time. Two components take the majority of effort: buildings and onroad emissions. For the buildings, we utilize an energy building model which we constrain through lidar data, county assessor parcel data and GIS layers. For onroad emissions, we use a combination of traffic data and GIS road layers maintaining vehicle class information. Finally, all pointwise data in the Vulcan Project are transferred to our urban landscape and additional time distribution is performed. In collaboration with our INFLUX colleagues, we are transporting these high resolution emissions through an atmospheric transport model for a forward comparison of the Hestia data product with atmospheric measurements, collected on aircraft and cell towers. In preparation for a formal urban-scale inversion, these forward comparisons offer insights into both improving our emissions data product and measurement strategies.