Car, Cities and CO2
Urbanization's Impact on Roadway Emissions – Evidence from a Novel High‐Resolution Dataset
Ian Sue Wing
Associate Professor, Department of Earth & Environment, Boston University
Vehicular carbon emissions accounted for 28% of U.S. fossil
fuel‐related CO2 in 2012, but the spatial distribution of these
emissions is highly uncertain. We have developed a new
emissions inventory, DARTE (Database of Road Transportation
Emissions), which reports CO2 emitted by U.S. road transport
at 1 km resolution annually for 1980‐2012. DARTE reveals that
urban areas are responsible for 80% of on‐road emissions
growth since 1980. At county and city scales, on‐road CO2
increases non‐linearly with population density.
While per‐capita emissions are falling at the national scale, localized emissions will
continue to rise as urban populations grow. DARTE’s construction from a roadway‐
level traffic dataset highlights the pitfalls of using spatial proxies to disaggregate
coarse‐scale source activity data. Comparisons with existing downscaled inventories
indicate biases of 100% or more in the spatial distribution of urban and rural
emissions. Given cities’ dual importance as sources of CO2 and an emerging nexus of
climate mitigation initiatives, high‐resolution estimates such as DARTE are critical for
both verifying the efficacy of actions to reduce emissions and for characterizing carbon
cycling at regional scales.
12:00‐1:00 FREE EVENT in Burke Auditorium, Kroon Hall
Lunch will be provided – first come, first served