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What are C40 Cities?
Blog...What are C40 Cities?

What are C40 Cities?

Net zero trajectory
train in a large city
This article explores C40 Cities, examining their mission, impact, and the important role they play in the fight against climate change.
train in a large city

Established in 2005, C40 Cities represent just under 600 million residents worldwide and are instrumental in reducing greenhouse gas emissions and climate risks, while increasing health, well-being, and economic opportunities. As urban areas continue to grow, the role of these cities is becoming increasingly crucial in shaping a sustainable future, demonstrating the power of collective action in the face of climate change. 

👉 This article explores C40 Cities, examining their mission, impact, and the important role they play in the fight against climate change.

What are C40 Cities?

C40 is a network of nearly 100 mayors across the world committed to addressing climate change. This initiative, which started in 2005, brings together urban centres from around the globe to collaborate on reducing greenhouse gas emissions and improving climate resilience. By adopting a science-based approach C40 mayors find themselves at the cutting edge of climate action.  

In 2005, London's then-mayor, Ken Livingstone, brought together leaders from 18 major cities to discuss urban climate policies and forge an agreement on reducing pollution. This meeting laid the foundation for what is now known as the C40 Cities Climate Leadership Group. Originally, the focus was on the biggest urban centers, but it has since expanded to include a wider range of cities, each facing unique environmental challenges.

Since its inception, the network has grown to include over 96 cities. This expansion is a clear indication of the increasing importance and need for considered urban responses to climate change. Each member city brings its own approach to environmental challenges, contributing to a wide variety of strategies and solutions.

One of the key aspects of C40 Cities is their adaptability. With such a diverse range of members, a one-size-fits-all approach is not the answer. Instead, the network thrives on the exchange of ideas and experiences, learning from each city’s successes and setbacks. This approach allows for more tailored and effective climate action strategies that suit a variety of different cities across the world.

As the C40 network has grown, so too has its influence on global climate policy. By bringing together cities from around the world, C40 has become a powerful voice in the conversation about how to build a sustainable future, proving the importance of urban action in the global fight against climate change.

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What is the objective of C40 Cities?

The mission of C40 is to help the world limit global heating to 1.5°C  by reducing greenhouse gas emissions while also improving the health, well-being, and economic opportunities of urban populations. This mission is underpinned by the acknowledgment that cities are both significant contributors to climate change and key to the solution. 

At the heart of C40's objectives is the goal of halving emissions by 2030, aligning with the Paris Agreement’s objective of limiting global heating to 1.5°C. C40 aims to achieve this by supporting mayors as they transition their cities to net zero emissions. 

The strategic objectives of C40 are determined by the elected Steering Committee. This is currently co-chaired by London Mayor, Sadiq Khan, and Freetown Mayor, Yvonee Aki-Sawyerr.  

👉 To learn more about the Paris Agreement head over to our blog

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How does C40 support mayors?

  • 1.5°C climate action plan support - C40 assists member cities in developing and implementing climate action plans aligned with the ambitious 1.5°C target of the Paris Agreement. These plans are not static - they are evolving documents, regularly updated to reflect changing circumstances and advancements in climate science.
  • High-impact accelerators and innovation - The C40 network encourages innovation through various accelerators, focusing on sectors with the most significant impact on emissions and climate resilience. This involves embracing cutting-edge solutions and technologies to drive faster and more effective climate action. Examples of accelerators include clean construction, net zero carbon buildings, renewable energy, and zero waste strategies. 
  • Equitable and thriving communities - A core component of C40's mission is to ensure that climate action also leads to the creation of equitable and thriving communities. This means addressing social and economic disparities, and ensuring that the benefits of climate action are shared by all, particularly the most vulnerable. There are a number of programs and initiatives led by C40 that support this aim. For example, Women4Climate focuses on gender equality and inspiring women to become climate leaders. 
  • International climate advocacy - C40 actively engages in international advocacy and diplomacy to raise global climate ambition. By showcasing the successes and lessons from urban climate actions, C40 influences global climate policy and encourages broader adoption of effective climate solutions.
  • Scaling action - Collaboration is key to C40's approach. The network facilitates the sharing of knowledge and best practices across cities, enabling them to learn from each other and scale up successful initiatives. This best practice and knowledge sharing encompasses a wide variety of climate-related topics, including adaptation and water, air quality, energy and buildings, food systems, transportation, ports and shipping, urban planning and design, and waste management. 
  • Access to finance - Recognising that funding is crucial for implementing climate actions, C40 helps cities access finance for investments in green jobs and projects that enhance urban resilience. This support is vital for cities, especially in developing regions, to actualize their climate action plans.
The overarching goal of C40 Cities is to demonstrate the potential of urban areas to lead the way in mitigating climate change. This involves not only direct action in individual cities but also influencing global climate policy by showcasing what is possible at the urban level. By achieving these goals, C40 Cities aims to pave the way for a sustainable future, proving that cities can be catalysts for environmental change and innovation.

C40 members

With over 96 C40 cities across the world, C40 membership is diverse. Among these, several cities stand out for their significant contributions and leadership. Notable members include New York, London, Paris, Tokyo, and Johannesburg, representing different continents and a range of urban challenges and opportunities. These cities, along with others like Los Angeles, Beijing, Mumbai, and São Paulo, exemplify the global reach and inclusive nature of the C40 network.

Membership criteria and leadership standards

Membership in C40 is unique in that it is earned through action rather than fees. The network sets rigorous, performance-based Leadership Standards, ensuring that every member city actively contributes to the collective mission of combating climate change. The key aspects of these standards include:

  • Developing inclusive and resilient climate action plans - Member cities are required to adopt climate action plans that are not only ambitious but also inclusive and resilient. These plans must align with the 1.5°C goal of the Paris Agreement and be regularly updated to remain effective and relevant.
  • Demonstrating progress - Cities must show progress in implementing their climate action plans. This involves not just setting targets but achieving measurable outcomes in reducing emissions and enhancing resilience.
  • Mainstreaming climate targets - C40 cities must integrate their climate goals into broader city decision-making processes. This mainstreaming ensures that climate considerations are a fundamental part of urban governance and policy-making.
  • Innovation - Cities in the C40 network are encouraged to innovate in areas beyond their direct jurisdiction, such as emissions associated with goods and services consumed within the city. This approach broadens the impact of their climate actions.
  • Showcasing climate leadership - Member cities are expected to be leaders on the global stage, inspiring and influencing other cities and stakeholders to take meaningful climate action. This leadership role is crucial in driving a worldwide movement towards sustainable urban development.
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The impact of C40 Cities

The role of C40 Cities in shaping global climate policy has the potential to be transformative. As a network, C40 Cities leverage their collective power to influence global agendas and drive meaningful change. This influence is evident in how these cities have become hotbeds for innovative climate solutions, setting examples for others to follow.

One significant impact of C40 Cities is their contribution to the advancement of green infrastructure and sustainable urban planning. For example, Copenhagen, a member of C40, has made remarkable strides in promoting cycling and renewable energy, aiming to become the world’s first carbon-neutral capital by 2025. Similarly, in New York City, the introduction of robust climate policies has led to substantial improvements in energy efficiency and a notable expansion of green spaces, enhancing both environmental health and urban liveability.

In the Global South, cities like Johannesburg are demonstrating the critical role of C40 Cities in adapting to climate change while addressing socio-economic challenges. Initiatives in Johannesburg focus on sustainable public transportation and energy-efficient building developments, aiming to reduce emissions while boosting economic growth and social inclusion.

The C40 network also encourages a collaborative approach among member cities, enabling them to share knowledge and experiences. This collaboration has led to the replication of successful strategies across different cities, amplifying the overall impact of the network. For example, the adoption of electric bus fleets first pioneered in cities like Los Angeles and later adopted by others, highlights the power of shared learning and collective action within C40 Cities.

👉 Discover how London’s Low Emission Zone is helping to cut GHG emissions in the city. 

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While the C40 Cities network has achieved significant successes, it also faces its share of challenges and criticisms. Addressing these is crucial for the continued effectiveness and credibility of the initiative.

One of the primary operational challenges in C40 Cities is the coordination and implementation of climate action plans across such varied city landscapes. Each member city has its unique environmental, economic, and social contexts, making it challenging to apply a one-size-fits-all approach. This diversity requires tailored strategies, which can complicate the process of sharing best practices and achieving cohesive action across the network.

Critics have also pointed out that while C40 Cities are leaders in climate action, they represent only a fraction of the world's urban areas. There is concern that the focus on major cities might overshadow the needs and contributions of smaller cities and towns, which are equally important in the global fight against climate change. Additionally, some experts argue that the ambitious goals of C40 Cities may not be fully attainable or could be hindered by political and economic constraints, particularly in cities with fewer resources.

In response to these challenges and criticisms, C40 Cities are continually adapting their approaches. The network emphasizes inclusive and equitable action, recognizing the importance of addressing the unique needs of each city. To tackle the issue of scalability and resource constraints, C40 provides support for cities to access financing and develop innovative solutions tailored to their specific circumstances. The network also engages in advocacy and diplomacy to influence wider policy changes that can facilitate the goals of all member cities, not just the major ones. This adaptive approach is key to ensuring that the network remains effective in leading urban areas towards a sustainable and resilient future.

👉 Discover Saudi Arabia’s recent development, The Line, a sustainable city that is being built in the desert. 

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What about Greenly?

At Greenly we can help you to assess your company’s carbon footprint, and then give you the tools you need to cut down on emissions. Why not request a free demo with one of our experts - no obligation or commitment required. 

If reading this article has inspired you to consider your company’s own carbon footprint, Greenly can help. Learn more about Greenly’s carbon management platform here.

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