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C40 Cities: How cities are making a difference to cleaning our air


Our Global Alliance is a network of global organisations committed to environmental action who share the ambition of The Prize to repair the planet, as well as academic and non-profit institutions and private sector alliances from around the world. Our Global Alliance and nominators are a key part of Earthshot, and as such, their news is great news for the environment and something we look forward to sharing on a regular basis.

This week, our Global Alliance Partner, C40 Cities, talk about how cities are delivering a sustainable and equitable recovery from the COVID-19 crisis, while reducing emissions with ambitious climate action, and cleaning our air.

C40 is a network of nearly 100 mayors of the world’s leading cities who are working to deliver the urgent action needed right now to confront the climate crisis and create a future where everyone, everywhere can thrive. Mayors of C40 cities are committed to using a science-based and people-focused approach to help the world limit global heating to 1.5°C and build healthy, equitable and resilient communities.

The COVID-19 crisis continues to present extraordinary challenges for people everywhere.

It has upended the world as we know it, yet the pandemic has also shown us how quickly things can change in a crisis. The way things are is not the way things have to be. This has important implications for how we can tackle the climate crisis. The science is clear: we must cut global emissions in half by 2030 to prevent runaway climate change and give us a chance to keep global heating to 1.5°C. Nothing short of transformational change on a planetary scale is needed within this decade, but such a shift has never seemed more possible than it does in 2021. Such action will not only slash emissions but also reduce toxic air pollution across the globe and improve the health of millions of people. Built on these ambitious targets, C40 mayors are seizing this unique opportunity to enact a Global Green New Deal, to secure the future of the planet now and for generations to come.

Breathing clean air is a human right. Air pollution, caused by the burning of fossil fuels, is simultaneously driving the climate emergency and claiming millions of lives each year. Just like COVID-19 and the impacts of a rapidly changing climate, air pollution doesn’t stop at national borders. Each of these interconnected threats demands swift, unprecedented and collective action. When many cities around the world entered lockdowns to reduce the spread of COVID-19, emissions fell and millions of urban residents breathed the cleanest air in generations. This demonstrates just how quickly air quality improvements will come when we stop burning fossil fuels to power our vehicles or drive our industries. The great challenge of our age is to deliver clean air without closing down societies. Fortunately, proven, cost-effective solutions already exist. We just need to deliver them at scale.

Cities are engines of change and with their ambitious actions, we can kickstart a green and just recovery from COVID-19, confront both the climate and air pollution crises, and create healthier societies. With ambitious and bold action for our people and our planet, mayors can ensure the communities we live in are equitable and inclusive, the livelihoods of everyone, everywhere are protected, and all people across the world can breathe clean air.

Mayors from the world’s leading cities have been on the frontlines of responding to the global COVID crisis. In their Green and Just Recovery Agenda, C40 mayors have outlined a plan to recover in a sustainable and equitable way from the pandemic, which is why they are now the fiercest drivers of this bold vision, backed up by action.

Creating 15-minute-cities

Mayors are taking steps for the health and well-being of residents by giving public space back to people and nature, reclaiming our streets and guaranteeing clean air to ensure liveable, local communities. As part of their Agenda for a Green and Just Recovery, mayors are creating ‘15 minute cities’ where all residents are able to meet most of their needs within a short walk or bicycle ride from their homes. By implementing the 15-minute-city concept, residents become better connected to their jobs, schools, leisure, and their loved ones, all while improving air quality by championing shorter trips and sustainable transport options. Across the C40 network mayors are implementing policies that incentivise walking and cycling, expanding public transport and through zero emission zones, encouraging people to leave their polluting vehicles behind.

Adopting Climate Action Plans

C40 works with cities to help them develop and implement integrated, inclusive climate plans which deliver action consistent with the objectives of the Paris Agreement. Climate action plans address the need to reduce greenhouse gas emissions, adapt to the impacts of climate change, and deliver wider social environmental and economic benefits. In December 2020, C40 research revealed that 54 cities, representing more than 200 million residents, are on track to help keep global heating below 1.5°C and confront the climate crisis due to their bold, science-based plans.

C40’s Air Quality experts are working with cities to evaluate how actions taken to meet ambitious global climate commitments can also meet local clean air goals and improve the health of residents. This provides invaluable information on the links between climate, air pollution, and public health to support more effective policy making that prioritizes climate change mitigation and public health improvement.

Clean Air Cities

Cities are also taking urgent action to ensure clean air for all. 37 mayors across the world are working to clean the air for the more than 150 million people that live in their cities. By signing the C40 Clean Air Cities Declaration, the mayors recognise that breathing clean air is a human right, and commit to working together to form an unparalleled global coalition for clean air.

Cities are also taking steps to expand access to air quality data, and address inequities in monitoring, to improve decision making and support community engagement. In London, Mayor Sadiq Khan is closing roads around schools to traffic at pick-up and drop-off times, protecting children’s health and reducing emissions from transport around schools by up to 23%. The ‘School Streets’ initiative uses cutting-edge air quality sensors by Breathe London, a programme piloted by C40 and the Greater London Authority with support from Children’s Investment Fund Foundation and the Clean Air Fund, and with continued support from the Greater London Authority, FIA Foundation and Bloomberg Philanthropies to expand the network and evaluate School Streets.

In Quezon City, Mayor Joy Belmonte is working with C40 to deliver on it’s Clean Air Cities Declaration commitments by deploying a sensor network to understand patterns in air pollution so policies can be targeted at communities that will benefit most. In Addis Ababa, C40 is working with the city to expand its pollution monitoring network, improve its emissions data, and evaluate the health benefits of cutting GHG emissions, key components in developing effective, data-driven policies. In Los Angeles, C40 is supporting the city in developing air quality initiatives as part of the LA Green New Deal, C40 Chair Mayor Eric Garcetti’s bold vision for a more sustainable and equitable future.

Cities are taking the bold and necessary actions to deliver a sustainable and equitable recovery from COVID-19, reduce emissions, and improve air quality for millions of residents across the world. 700+ cities have already committed to Cities Race to Zero – a worldwide effort to reach net-zero emissions through ambitious, science-backed action.

But we cannot achieve the transformational change we need alone. Collaboration and coalition can accelerate our shared climate goals and ensure the future for generations to come. C40 is working with youth climate activists, business leaders, unions and residents to build a Global Green New Deal that serves everyone.

When we work together, we can confront the climate crisis and ensure a zero-emission future, where everyone, everywhere can breathe clean air.


Learn more about the work of C40 Cities
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