A new methodology for quantifying on-site residential and commercial fossil fuel CO2 emissions at the building spatial scale and hourly time scale

In order to advance the scientific understanding of carbon exchange with the land surface, and contribute to quantitative-based US climate change policy interests, quantification of fossil fuel CO2 emissions (the primary greenhouse gas), at fine spatial and temporal scales, is essential. Known as the ‘Hestia Project’, this pilot study has quantified all fossil fuel CO2 emissions down to the scale of individual buildings, road segments and industrial/electricity production facilities on an hourly basis for the greater Indianapolis region, IN, USA. Here, we describe the method used to quantify the on-site fossil fuel CO2 emissions in the residential and commercial sectors. By downscaling the Vulcan Project’s 2002 county-level commercial and residential fossil fuel CO2 emissions, we quantified the CO2 emissions for all building structures using a combination of multiple datasets and energy simulation. At the landscape scale, the spatial variation in CO2 emissions is driven by building density, height and type. Within the urban core, larger emissions are driven by the larger amounts of energy consumed per unit floor area. The resulting dataset and corresponding methods will be of immediate use to city environmental managers and regional planning agencies, enabling the analysis of alternative strategies to lower fossil fuel CO2 emissions. The results obtained here will also be a useful comparison to atmospheric CO2 monitoring efforts aimed at constraining the land surface net carbon exchange via atmospheric sampling.