Fixing greenhouse gas accounting at the city scale

Alongside COP21 in Paris, nearly 400 city mayors pledged to reduce urban greenhouse gas emissions, in some cases by dramatic amounts. As part of these pledges, mayors committed to count and track their emissions using a particular approach, the Global Protocol for Community-scale GHG emissions (GPC).

The GPC and most other, prior community-scale protocols like it, evolved from IPCC-based GHG accounting rules developed at the national scale, and where principles such as completeness, comparability and accuracy are paramount. At a local scale, however, different principles – namely, relevance – may become more important, given the different focus and governance structures of city governments.

This article proposes improvements to local-scale GHG accounting approaches, including the GPC, that would delineate categories of emissions sources and activities over which local policy-makers have more or less influence. For many cities, a primary, or “core” category of emissions could be devoted to CO2 from buildings and passenger transport, and CH4 from waste management. The authors argue that simplifying and focusing city-scale GHG accounting on these sources would improve the policy-relevance of city-scale GHG accounting and make it easier for cities to play effective roles in the global mobilization to limit warming to “well below” 2°C.

Read the article (external link to journal)