Cities Act

Five years ago, 40 of the world’s leading mayors came together and made a commitment to work collaboratively to address one of the greatest economic, social and environmental challenges of our time. Since then, the urgency to respond to global climate change in urban centers has only increased. And in every respect, our cities continue to be at the forefront of this issue — as innovators and practitioners. Every mayor of every C40 city knows well that we cannot afford to wait for national governments to agree on the right approach to addressing global climate change. While international negotiations continue to make incremental progress, C40 cities are forging ahead. Acting both locally and collaboratively, cities are making a meaningful global impact by implementing sustainability practices. Each city is unique in its infrastructure, scope of control over municipal services, technical savvy and progress in addressing climate change.

The 58 cities now represented within the C40 account for 8 percent of the global population, 12 percent of global greenhouse gas emissions and 21 percent of global GDP. Our cities control significant economic, environmental, and social assets — and have enormous potential to set the framework for a low carbon economy. To date, however, there has been no attempt to measure the true impact of local action, or to capture the value of the C40 network.

The C40 commissions Arup to co-author this report as the first-ever comprehensive analysis of actions underway in the world's megacities to address climate change. This baseline clearly illustrates the notion that “Cities Act.” To date, there are 4,734 actions currently in effect and another 1,465 under consideration.

This study is more than just proof of action, it is also an expression of opportunity. By taking an inventory of mayoral powers, it demonstrates the ability of cities to act today; by supporting knowledge-transfer and collaboration among cities, it enables the C40 to make an even greater impact on climate change going forward.

Clearly, there is no single solution for solving global climate change. However, cities have the ability, capacity and will to lead. This study not only underscores what cities have done to date, but also what they can do now and in the future as local leaders, and as a collective, to have a significant global impact.

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