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Global cities convene in London to tackle triple threat of congestion, air pollution and the climate emergency

  • Mayor of London and Chair of C40 Cities Sadiq Khan is convening global cities to accelerate city-led action to address the triple threat of congestion, air pollution and the climate emergency.
  • Representatives from 16 C40 cities will attend the Air Quality and Climate Solutions Summit held at London City Hall.
  • C40 to begin working with 12 cities in the Global South to advance targeted projects aimed at tackling toxic pollution.

The Mayor of London and Chair of C40 Cities is today convening 16 major global cities, seven of which are from the Global South, to accelerate city-led action related to the triple threat of congestion, air pollution and the climate emergency.

In partnership with the World Health Organization (WHO) the mayor will be joined by representatives of 16 C40 cities, as well as health experts, youth activists and union leaders at London’s City Hall to kick off a three-day study tour. Cities will have the opportunity to experience first-hand London’s leading environment and transport policies, including the world’s first 24 hour Ultra Low Emission Zone (ULEZ).

Today the Mayor is releasing new data from the expansion of the ULEZ to cover an area with a population of 4 million people. There were 67,000 fewer non-compliant vehicles in the zone on an average day compared to the period right before the ULEZ expanded. As a result, the scheme has helped reduce nitrogen dioxide (NO2) levels in inner London by 20 per cent, building on a reduction in central London of 44 per cent.

A quarter of London’s carbon emissions come from transport. To address this, the mayor has set a target for London to be net-zero by 2030. Earlier this year, London’s City Hall revealed that the cost of traffic congestion to London’s economy stands at £5.1 billion a year, and warned that unless efforts to deliver a green, sustainable recovery from the pandemic increase, the capital could lurch from one public health and economic crisis to another, caused by filthy air and gridlocked roads.

Toxic air kills more than 8 million people worldwide each year, and is responsible for a range of health problems, including asthma, heart disease, premature births and reduced cognitive performance. Over 99 per cent of residents of C40 cities reside in areas with air pollution levels deemed unhealthy by the WHO. The burden of outdoor air pollution falls disproportionately on people in low and middle-income countries, where 91 percent of premature pollution-related deaths take place, according to the WHO.

As Chair of C40, Mayor Khan has committed to putting social justice at the heart of his vision for C40 cities and has already delivered on his key pledge to direct a record two-thirds of the C40 budget towards Global South cities. In line with Mayor Khan’s commitment to tackle air pollution worldwide, C40 will work with twelve cities in the Global South, with support from the Clean Air Fund, to advance targeted projects aimed at reducing air pollution and improving public health. C40 will support cities with air quality and health data collection, analysis and management, the delivery of policies to create low emission zones, zero emission areas, vehicle emissions testing programmes, freight measures and other actions, as well as communication and citizen engagement strategies to support the implementation of the policies and programmes.

Bengaluru, Bogota, Delhi, Lima, Quezon City, Mexico City, and Rio de Janeiro will be working with C40 through a variety of locally tailored air quality projects aimed at accelerating action in key sectors. In Bogotá, Bangalore and Delhi, for example, C40 is supporting the development of hyperlocal air quality monitoring capacity to generate data for policy change; in Bogotá, Rio and Lima, C40 is supporting the design of zero or low emission zones to reduce traffic emissions, and in Mexico City, C40 will work with the city to reduce emissions from freight, a major source of pollution. Through this work, C40 aims to reduce the 70,000 deaths and 75,000 new cases of childhood asthma occurring each year due to air pollution in these cities.

C40 will support five additional cities on the African continent to generate regional momentum on air quality through C40’s African Cities for Clean Air programme.

Sadiq Khan, Chair of C40 Cities and the Mayor of London, said: “We are facing a pivotal moment in our efforts to tackle the triple dangers of toxic air pollution, climate change and congestion. I’m delighted to host these global cities and hope what they see in London, like the ULEZ which has reduced by almost a half toxic air in Central London, inspires them to take ambitious action to protect the health of their citizens and support their economies.

“To support these efforts, I am thrilled to announce today that C40 Cities are supporting twelve Global South cities with their plans to tackle toxic pollution. We simply don’t have time to waste – deadly air pollution is permanently damaging the lungs of young children and affecting older people who are more vulnerable to the impacts of poor air quality. This is also about social justice – we know pollution hits the poorest and most vulnerable the hardest, which is why I’m working with C40 doing everything I can to improve air quality and protect the health of our residents.”

Michael R. Bloomberg, UN Special Envoy on Climate Ambition and Solutions, President of the C40 Board and 108th Mayor of New York City, said: “Cities are laboratories of innovation, and by sharing what works with others around the world, they can dramatically increase the pace of progress on the toughest global challenges, including air pollution and climate change. The Air Quality and Transport Solutions Summit brings together global city leaders to build partnerships—with organizations like C40 and cities like London—and spread data-driven solutions ​around the world. Improving air quality in cities will strengthen public health and drive economic growth, while also addressing many of the causes of climate change.”

Dr Maria Neira, Director of WHO’s Department of Public Health and Environment, said: “The climate and pollution crisis are killing millions of us every year. We can no longer compromise on clean air. We need the engagement of mayors, we need strong interventions at urban level to confront this massive public health challenge. Be ambitious, a healthy society is the best reward.”

Rosamund Adoo-Kissi-Debrah, Founder, Director and Trustee of The Ella Roberta Foundation, said: “Air pollution has become normalised in our society due to its invisibility: On every walk to school, bike ride, and every time children play outside, their bodies are absorbing the toxic air spewed out by petrol and diesel vehicles. Children – like my daughter Ella – die horrible, early deaths as a result. In London every year childhood asthma deaths are still between 8-12. Little lungs are being permanently stunted. Little brains are suffering from impaired cognitive development. As filthy air combines with climate-changed heat advisories, I feel terrified for the health of children in our city. Air pollution is a silent pandemic, and unless we clean up the air, we will never have social justice or resolve climate change. Ella would be alive today if air pollution around our home had been within the WHO acceptable limits. I’ll be watching to see how the results of this study tour translate into real life action for London, and other cities involved. Clean energy and better public transport save lives. We cannot wait any longer. Breathing clean air is every child’s human right, and that’s what should be normalised.”

Claudia López, Mayor of Bogotá, said: “The Zonas Urbanas por un Mejor Aire (ZUMA) is a priority project for the Bogotá we are building – a more sustainable, caring, fair and regreening city. It will reduce emissions from both industry and transport, encourage active mobility, increase green areas, reduce air pollution exposure and improve the health of many of Bogotá’s residents and visitors. In partnership with C40, and under our initiative ‘Unidos Por Un Nuevo Aire,’ we will monitor air quality improvements, measure the benefits throughout this project and develop the roadmap for the implementation of the first ZUMA.”

Miguel Romero, Mayor of Metropolitan Lima said: “Lima is proud to implement Peru’s first low emission zone in the historic centre of Lima. With the support of C40, we will highlight the benefits of this low emission area and demonstrate its use as an urban revitalisation tool. Improved air quality leads to greater health and wellness, and increased public space allows for the creation of new cultural and recreational attractions. We hope to create a model for other Peruvian (and Latin American) cities to replicate and implement their own low emission zone.”

Ma. Josefina G. Belmonte, the Mayor of Quezon City, said: “Through the Air Quality Technical Assistance Programme, Quezon City is empowered to manage its air quality with the skillful guidance of C40 Cities and its relevant partners. Real-time data across the city is now being monitored as basis in crafting specific air quality management strategies and actions – identifying sources and locations of focus while providing guidance on health and exposure of our citizens. By analysing the impacts of transport sector policies, we hope to promote active mobility and the expansion of clean and efficient transport.”

Juliet Oluoch, youth activist from Nairobi, said: “I call upon individuals, organizations, local and National governments to collectively work towards improving the air quality in cities because only that way we can beat climate change. I desire a future where breathing clean air is a human right and going to the store, to school or to work does not create pollution.”

Asheer Kandhari, youth activist from Delhi, said: “To me, coming from a country like India, the climate crisis is more than evident on a day-to-day basis. I see it in the perpetually hazardous air quality, the scorching heat waves of the summer, the extreme precipitation events and so much more. As children in school, we are taught that three basic elements are needed for our survival: air, water and food. Yet, at this point in time, a majority of India’s population is being deprived of not one but all three of these necessities.”

C40-supported projects

  • Bogota: C40 is supporting the city on hyperlocal air quality monitoring and designing interventions for a bold new zero emission area programme to improve air quality in highly polluted areas and places where vulnerable communities reside.
  • Bangalore: C40 is working with the city to implement India’s Clean Air Action Plan at the city level.
  • Delhi: C40 is supporting the city in meeting its goal of achieving India National Clean Air Programme targets by 2024 by building capacity for air quality monitoring and analysis, supporting collaborative air quality planning across city departments, and integrating community input into local air quality management.
  • Lima: C40 is working with the city to reduce emissions from the transport sector through the development of a low emission zone. This will provide a model for other Peruvian cities in addressing traffic-related emissions.
  • Mexico City: C40 will work with Mexico City to implement its new air quality management plan, ProAire, with a focus on developing strategies to address emissions from freight, a major source of air pollution.
  • Quezon City: C40 will work with the city to implement its Air Quality Management Plan and enhanced Local Climate Change Action Plan 2021-2050.
  • Rio de Janeiro: C40 is working with the city in delivery of a Low Emissions Zone and providing critical air quality monitoring technical assistance. By implementing actions to improve air quality and encourage clean transportation and active mobility, Rio’s LEZ aims to create 35,000m2 of healthy urban space by 2024.

About C40 Cities Climate Leadership Group
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. Through a Global Green New Deal, mayors are working alongside a broad coalition of representatives from labour, business, the youth climate movement and civil society to go further and faster than ever before.

The current Chair of C40 is Mayor of London Sadiq Khan; three-term Mayor of New York City Michael R. Bloomberg serves as President of the Board. C40’s work is made possible by our three strategic funders: Bloomberg Philanthropies, Children’s Investment Fund Foundation (CIFF), and Realdania. To learn more about the work of C40 and our cities, please visit our website and C40 Knowledge Hub or follow us on Twitter, Instagram, Facebook and LinkedIn.

About the C40 Clean Air Cities Declaration
Cities are taking bold action to tackle air pollution and clean the air we breathe. Through the C40 Clean Air Cities Declaration, 48 cities (including those announced today) have committed to establish baseline air pollution levels, set ambitious targets which meet or exceed national commitments and implement new substantive policies and programmes to address the top causes of air pollution emissions.

Through the declaration, mayors commit to use their power and influence to reduce air pollution and work towards meeting the World Health Organisation’s Air Quality Guidelines. This means cities will continually reduce their local emissions, and advocate for reductions in regional emissions, resulting in continuous declines in air pollution levels that move towards the WHO guidelines. About Bloomberg Philanthropies’ Global Clean Air Program Bloomberg Philanthropies leads the world’s most ambitious clean air effort that aims to improve air quality through support for pilot projects in cities, as well as partnerships with national governments and organizations. This includes initiatives in Brussels, Jakarta, London, Milan, Paris, Warsaw, and other governments around the world.

About Bloomberg Philanthropies
Bloomberg Philanthropies invests in 941 cities and 173 countries around the world to ensure better, longer lives for the greatest number of people. The organization focuses on five key areas for creating lasting change: the Arts, Education, Environment, Government Innovation, and Public Health. Bloomberg Philanthropies encompasses all of Michael R. Bloomberg’s giving, including his foundation, corporate, and personal philanthropy as well as Bloomberg Associates, a pro bono consultancy that works in cities around the world. In 2021, Bloomberg Philanthropies distributed $1.66 billion. For more information, please visit or follow us on FacebookInstagramYouTubeTwitter and LinkedIn.

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