Under-reporting of greenhouse gas emissions in U.S. cities

• Published in: Nature communications 2021-02, Vol.12 (1), p.553-553, Article 553
• Main Authors: Gurney, Kevin Robert, Liang, Jianming, Roest, Geoffrey, Song, Yang, Mueller, Kimberly, Lauvaux, Thomas
• Format: Article
• Language: English
• Subjects: 704/106/694/682; 704/844/2739; 704/844/4066/4075; Carbon dioxide; Carbon dioxide emissions; Cities; Emission inventories; Emissions; Fuels; Greenhouse effect; Greenhouse gases; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary); Sciences of the Universe; Transportation
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-20871-0

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%. Differences arise because city inventories omit particular fuels and source types and estimate transportation emissions differently. These results raise concerns about self-reported inventories in planning or assessing emissions, and warrant consideration of the new urban greenhouse gas information system recently developed by the scientific community. Many cities in the US self-report greenhouse gas emissions. Here, the authors find that US cities under-report their own greenhouse gas emissions, on average, by 18.3% because city inventories omit some fuels and source types and estimate transportation emissions differently.