The world’s first crowd-sourced sustainability index for cities highlights drivers of urban greenhouse gas emissions and trends in sustainability. The Sustainable Cities Index analyzed 50 cities, finding that the greenest are predominantly in Europe and more likely to have female mayors. The greenhouse gas footprints of cities are dominated by consumption emissions, as opposed to transportation emissions or emissions from buildings.
Developed by us and our colleagues at Corporate Knights, the Sustainable Cities Index will be published annually. The index draws on publicly disclosed data and consists of 12 indicators related to greenhouse gas emissions, resilience, air quality, land use and transportation, water, waste, and sustainability policies. Local governments of any size, anywhere in the world, are invited to join the new index by registering on the user-friendly data hub and entering a few key data points. Below, we dive into three notable findings from the inaugural 2022 Sustainable Cities Index.
Female mayors lead the way
Female mayors are distinguishing themselves as climate leaders; although the assessed cities have predominantly male mayors, 50% of the top 10 cities in the Sustainable Cities Index are led by women.
The three highest-ranking cities—Stockholm, Oslo, Copenhagen—have female mayors. There’s no single explanation for this and it would be folly to attribute the high rankings to this solely. However, this observation cannot be chalked up to chance, as female mayors are also leading bold sustainability initiatives elsewhere in the Global North—Calgary, Paris, Montreal, and Stockholm—and in the Global South in Accra, Mexico City, and Bogotá.
Consumption drives urban GHGs
The Index’s simple yet robust method for estimating the emissions embedded in food, electricity, and other consumed goods reveals the surprisingly high contributions of consumption to each city’s total emissions footprint.
City carbon footprints are often thought to be dominated by sectors like transportation, building waste and industry; however, our analysis found that consumption emissions can far exceed them. For example, Stockholm (currently the top-scoring city in the index) has sector-based (Scope 1 and 2) emissions of 1.5 tonnes of CO2e per capita, but a consumption-based inventory (Scope 3) of 9 tonnes of CO2e per capita. To maximize their impact on emission reductions, cities need to reduce their consumption-based emissions.
North American cities must learn from Europe
North American cities lag behind European cities in the sustainability transition.
Scandinavian cities alone claim five of the top 10 positions. European cities have a longstanding history of innovative and ambitious visions of urban sustainability and are incentivized and supported by European Union laws and policy frameworks. North American cities typically lack this strong foundational direction.
Canadian cities make up 70% of North American cities in the top half of the Sustainable Cities Index. Overall, American cities lag in sustainable transportation infrastructure (with a heavy reliance on cars), overconsume water, and overproduce waste. North American cities should look to their neighbours across the pond to adopt policies and strategies that will drive profound climate change action.
How sustainable is your city?
To find out how sustainable your city is, and continue exploring the results of the 2022 Sustainable Cities Index, visit the Corporate Knights website and read the technical report. You can also download the full data and scores to adjust the weighting of each indicator to see how it would affect the rankings. Even better, add your city to the index by registering it on the interactive data hub and providing a few key data points. The Corporate Knights research team will verify the data to score and grade your city, and you will receive a report comparing your results with other cities for each of the twelve indicators in the index.