Working with Cities to Reduce Greenhouse Gas Emissions

Prepared for
Children's Investment Fund Foundation
greenhouse gas emissions


The Children’s Investment Fund Foundation is collaborating with the C40 Cities Climate Leadership Group and Mathematica’s Center for International Policy Research and Evaluation to examine how the Global Protocol for Community-Scale Greenhouse Gases (GPC) may be used to help cities reduce their greenhouse gas emissions. The C40 group will assist 30 large cities in fully using the GPC. The Mathematica team will evaluate both the C40 group’s assistance and whether a comprehensive emissions inventory fosters greater city-level action to mitigate climate change.

Cities are an important target for efforts to reduce greenhouse gas emissions. They house more than half of the world’s population, account for over two-thirds of global energy demand, and release more than 70 percent of global energy-related carbon dioxide emissions. Many cities are also highly vulnerable to extreme weather events and rising sea levels as a consequence of global warming. Fortunately, cities are becoming more active in addressing climate change. Many have committed to reducing their greenhouse gas emissions and are undertaking efforts to fulfill those commitments.

The GPC, which was released in December 2014, is designed to assist cities by providing guidance in developing accurate inventories of their greenhouse gas emissions. The GPC helps cities select appropriate geographic boundaries for measuring emissions, develop a comprehensive list of emissions-producing activities, and then translate measures of those activities into their corresponding emissions. Once in place, the inventories enable cities to set emissions-reduction goals and develop well-targeted plans for achieving them. The GPC also provides a way for cities to track progress and to be held accountable for promised reductions in emissions. An important feature of the GPC is that estimates from cities lend themselves to aggregation without double counting the underlying emissions.

C40, a worldwide group of 83 megacities that are committed to addressing climate change at the urban level, will provide 30 of its member cities with technical assistance to prepare GPC-compliant inventories of their greenhouse gas emissions and identify appropriate city-level actions to reduce those emissions ( C40 will deliver workshops and other assistance tailored to each city, and each participating city will provide local personnel charged with developing the inventory and associated action plans. The program’s goal is to build sustained capacity in the 30 cities and to learn more about how all cities may use the GPC.

Mathematica’s role is to address the following four research questions:

  1. Do cities that receive the foundation-funded GPC technical assistance produce GPC-compliant inventories?
  2. Does receiving the GPC technical assistance lead cities to report GPC-compliant inventories more quickly and/or produce higher quality inventories relative to similar cities that do not receive such assistance?
  3. Does the GPC technical assistance lead to more and better city actions directed to reducing greenhouse gas emissions relative to similar cities that do not receive the assistance?
  4. Does reporting a GPC-compliant inventory lead to more and better actions to reduce greenhouse gas emissions relative to similar cities that do not report such an inventory?

The study will combine several analytic approaches, including both quantitative and qualitative methods, in order to address the research questions. Mathematica will examine the extent to which C40’s technical assistance in particular and the GPC in general have increased and improved city-level efforts to slow climate change. Even though the evaluation is still in the design phase, Mathematica expects to use data from cities’ reports produced under the auspices of the Carbon Disclosure Project to describe cities’ emissions, climate action plans, and other characteristics. The study team will release its initial assessment of the available data later in 2016 and will issue annual update briefs, with the final report released in January 2020.