How the 2024 UESI adds crucial context to the global conversation on city-level climate action

This blog was originally written for the Data-Driven EnviroLab in June, 2024.

The Data-Driven EnviroLab (DDL) launched our 2024 Urban Environment and Social Inclusion Index (UESI) in September. For details on our updated key findings, read our latest blog.

With our recent updates, the UESI now includes 278 cities and almost 16,600 thousand districts, comprising cities from all continents, except Antarctica, and from multiple levels of development.

In addition to new cities, our latest iteration of the UESI saw multiple methodological updates, including the addition of a new Climate Change category.

The Climate Change category tracks cities’ emissions emissions performance and proposed climate mitigation strategies and identifies which global cities are taking credible, comprehensive action to reduce climate emissions. As cities are home to 4.2 billion people, and responsible for an estimated 67-72% of global emissions, it is imperative to deepen our understanding of how cities are performing with respect to realized emissions and climate action goals.

To this aim, the Climate Change category is explored through two composite indices: a Greenhouse Gas Emissions Index and a Climate Policy Index.

The GHG Emissions Index scores the UESI cities on their level of territorial carbon dioxide (CO2), nitrous oxide (N2O),  and methane (CH4) emissions and total carbon footprint (i.e., consumption-based emissions) considering four aspects: GHG emissions trends from 1970-present to evaluate the performance over three distinct periods; the emissions per capita for the latest available year; the emissions per km2; and the direct and the carbon footprint per capita for the latest year available.  Each of these dimensions is scored and weighted through an optimization approach to create a composite index that provides a comprehensive evaluation of each city’s overall emissions performance.Fig. 1: Distribution of GHG Emissions Index Score by Region

The results of this indicator show that highly developed cities have lower carbon footprint scores, and that their consumption-based emissions can be 5 to 10 times higher than their territorial emissions, emphasizing their major role in global emissions and climate change mitigation. Territorial emissions, on the other hand, are highly variable depending on the gas. We can observe interesting trends, however, such as higher CH4 scores for developed regions, which suggests the relocation of high-emitting sectors outside city boundaries such as waste facilities. This finding underscores the importance of accounting for consumption-based emissions in order to have a complete picture of a city’s real climate impact.

The Climate Policy Index uses data from the Net Zero Tracker database to assess cities’ climate action target-setting, ambition, transparency and comprehensiveness. Combined, these four attributes help to paint a picture of the scope, detail, credibility and reporting mechanisms of a UESI city’s climate action goals. Scores are optimized using a similar approach to the GHG Emissions Index to develop a composite index.Fig. 2: Distribution of Climate Policy Index Score by Region

Applying this framework to cities’ climate policies, we find that many lack ambitious climate targets and concrete mitigation strategies. Although roughly half of global cities have climate action targets whose ambition is on-par with their nation’s targets, many cities, particularly in the Global North, are lacking climate action plans with detail and ambition. 67 UESI cities have no climate action plan, and 15 percent of cities in the US and Europe have less ambitious climate action strategies than their national counterparts.

With the inclusion of Climate Change, the UESI  now covers six themes: Air Quality, Urban Heat, Climate Change, Water and Sanitation, Urban Ecosystem, and Transportation. Each of these indicators provides detailed insights into a city’s performance within that area, and helps to paint a more complete picture of what factors help, and hurt, a city’s environmental performance and equity.