Mightier than they seem: a commentary on the broad impact of city-based climate action

This commentary argues that by focusing narrowly on the direct legal powers of cities, traditional approaches to estimating the ability of cities to lead a global transformation to a low emission world vastly underestimate the potential of city-led change. While there is consensus that about 70% of the world’s greenhouse gas emissions can be attributed to cities, or to the activities needed to sustain them — perhaps, according to some estimates, even more — there is less of a consensus about the actual legal and financial potential of city governments to enact the changes needed to reduce these emissions. Some studies have taken the position that cities, alone, cannot impact more than a portion of these emissions (see for example the Coalition for Urban Transitions, 2019). In fact, as demonstrated by the leadership of mayors of the world’s major cities, cities have an ability to influence and lead climate action well beyond the limits of their stated legal powers or the limits of their financial ability. Indeed, the examples are so compelling that they stand for the proposition that by influencing change well beyond borders, city-based climate action can make the critical difference to the world’s rapidly diminishing ability to prevent climate breakdown. Real world examples call into question any analysis merely based on an examination of cities’ legal authority. Such an approach inevitably will conclude that the impact of city actions is limited.