2 February 2021: Paper published in Nature Communications which reports that “Cities dominate greenhouse gas emissions. Many have generated self-reported emission inventories, but their value to emissions mitigation depends on their accuracy, which remains untested. Here, we compare self-reported inventories from 48 US cities to independent estimates from the Vulcan carbon dioxide emissions data product, which is consistent with atmospheric measurements. We found that cities under-report their own greenhouse gas emissions, on average, by 18.3% (range: −145.5% to +63.5%) – a difference which if extrapolated to all U.S. cities, exceeds California’s total emissions by 23.5%.” Access the full paper here. The research has attracted a lot of reporting – Reuters, Bloomberg, Science Daily, New York Times, and Wired.
Over the past decade, focus has (rightly) grown on cities and their contribution to national greenhouse gas emissions and – more importantly – the opportunities that cities have to reduce these emissions. Alongside this there has been increasing work undertaken on measuring urban emissions – most notably by C40 Cities. This new research is a further contribution to this subject and highlights the challenge policy makers and others have in measuring emissions at the local level in the complex environment of a city.