CoolClimate Network

This study develops a consumption-based greenhouse gas inventory of all San Francisco Bay Area census block groups, cities and counties. It is the first study to explore household carbon footprints at such fine geospatial resolution for any region. The methodology incorporates local consumption and emissions data wherever possible. In other cases, consumption is approximated using econometric analysis of national and statewide transportation and household consumption survey responses by S.F. Bay Area residents. The consumption-based method results in about 35% higher GHG emissions than the traditional territorial approach for the region, largely due to higher emissions from imported food and goods. Transportation is the largest source of emissions (33%), followed by food (19%), goods (18%), services (18%) heating fuels (5%), home construction (3%), electricity (2%) and 1% waste. Within the region there are large differences in the size of average household carbon footprints (HCF) between cities (>2.5x) and larger differences between neighborhoods within populous cities (~5x). These differences suggest large inequalities in climate responsibility within a single metropolitan area. The composition of household carbon footprints also varies considerably between different locations, with vehicle ownership, income, household size and home size contributing the most to differences. The study concludes with recommendations to prioritize policies and programs for different locations.