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Urban Giants Leading the Climate Charge While Nations Lag Behind
Every morning when city mayors around the world wake up, they’re not thinking about abstract global temperature targets – they’re thinking about flooding, heat waves, and choking air quality in their own backyards. Cities are indispensable actors in the climate transition, and despite acute financial and institutional shortfalls many face, this Report shows that cities are leading the way through innovative, community-led approaches. While national governments continue to struggle with partisan politics and international negotiations, local leaders are rolling up their sleeves and getting things done. The data tells a stark story: currently, 56% of the world’s population live in cities and 70% of people are expected to live in urban areas by 2050. Yet these urban areas also account for more than 70% of global CO2 emissions. The math is simple – if we’re going to solve climate change, it’s going to happen in cities.
The Billion-Dollar Climate Finance Reality Check
Here’s where things get interesting – and expensive. For mitigation alone, cities require an estimated USD 4.3 trillion annually from now until 2030, and over USD 6 trillion per year from 2031 to 2050. That’s not a typo. To put this in perspective, that’s more money than most countries’ entire GDP. But here’s the kicker: The majority of urban climate finance (69%) was sourced and provided domestically, and this trend is likely to grow. This is particularly true for private flows, where domestic sources accounted for 96%. Cities aren’t waiting for international handouts – they’re finding ways to fund their own green transformations. Through 2030, cities require annual investment of USD 1.7 trillion for transport solutions (e.g., EVs and urban rail systems), USD 1.2 trillion for energy (particularly for renewable power and heat generation), and USD 1 trillion for buildings for retrofits and new construction. The transportation and energy sectors are eating up the biggest chunks of this financial pie.
European Cities Setting the Global Standard
Europe isn’t just talking about climate action – they’re putting their money where their mouth is. In March 2024, a 2nd batch of 23 cities received the EU Mission Label and in October 2024 a 3rd batch of 20 cities, bringing the total number of cities with the EU Mission Label to 53. These aren’t just participation trophies – The EU Mission Label is an important milestone in the cities’ work. It acknowledges successful development of Climate City Contracts and it is intended to facilitate access to EU, national, and regional funding and financing sources, in particular private investment. Meanwhile, climate action is by far the top priority for European mayors according to the latest Eurocities survey. What’s driving this urgency? In 2024, the continent witnessed catastrophic floods in Spain and Slovenia, unprecedented heatwaves in Italy and Greece, and droughts that ravaged agricultural regions in southern France. When your city is literally underwater or burning up, climate action stops being a political issue and becomes a survival issue.
America’s Patchwork of Local Climate Leadership
The United States presents a fascinating case study in climate federalism. 45 states, plus the District of Columbia, Puerto Rico, and dozens of Metropolitan Statistical Areas have now developed climate action plans through investments made possible by President Biden’s Investing in America agenda. But here’s where it gets complicated: As of February 2022, 15 of the 50 largest cities in the U.S. by population had not adopted local climate action plans. That’s a pretty significant gap. The cities that are moving forward aren’t messing around though. We found that a strong plurality (40%) of all strategies target municipal operations, nearly half (49%) of all strategies are focused on creating new plans and assessments, and energy and mobility contribute to nearly half (43%) of all strategies. Critics argue this focus on municipal operations is missing the bigger picture, since these operations only account for 1-5% of total community emissions.
The Global Mayor Networks Taking Names
City leaders aren’t going it alone – they’re forming powerful alliances that rival traditional diplomatic channels. In 2024, 15% of scored cities worldwide demonstrated leadership in environmental transparency and climate action. This reflects an increase in the proportion of scored cities achieving CDP’s highest rating for environmental leadership and transparency rising to 15% in 2024 from 13% in 2023. The Global Covenant of Mayors for Climate & Energy now includes more than 12,500 cities stand ready to partner with national and international institutions to tackle both climate and economic crises through local initiatives, innovative financing models, and sustainable infrastructure. That’s not just a network – that’s a movement. Climate Mayors is a bipartisan network that has mobilized more than 750 U.S. mayors since 2014, demonstrating climate leadership through meaningful actions in their communities. These aren’t just talking shops – these networks are sharing real solutions, real money, and real results.
Innovation Hubs Emerging from Urban Laboratories
Cities have become the world’s most important climate innovation laboratories, testing solutions that national governments could never attempt. In the fight against climate change, cities and counties have become important leaders because of their role as laboratories, incubators, and implementers of climate solutions. Because local governments can be more responsive than those at the state and federal levels, and because and they are so , cities are playing a prominent role on the international stage in galvanizing climate action. Take London, for example: By March 2024, the academy had trained over 6,500 people and helped secure green jobs for 3,350, focusing on skills development in retrofitting, green spaces, renewable energy, electric vehicles, and low-carbon transport. Or consider NYC’s massive solar push: The 72 schools with solar arrays – 58 completed and 14 more expected to be complete by the end of the year – will represent nearly 17 Megawatts of the City’s solar production, nearly tripling the municipal solar capacity. These aren’t pilot projects – they’re full-scale transformations.
Asian Cities Joining the Climate Leadership Revolution
Asia’s megacities are no longer climate laggards – they’re becoming climate leaders in their own right. The Mayor noted an example in Yokohama’s partnership with the Philippines, through which Yokohama’s sharing of waste management expertise allowed Mandaue City in the Cebu Metro area to increase waste separation and plastic recycling, reducing annual waste by 4,500 tons in 2023, and enabling a 3,000 ton decrease in carbon emissions. This isn’t charity – it’s smart climate diplomacy that creates win-win situations. The summit hosted at the Vatican by Pope Francis, “From Climate Crisis to Climate Resilience,” was held from May 15-17, 2024, and invited mayors and governors representing local cities and regions from around the world to gather in the Vatican City and share and discuss their respective climate action initiatives. When city mayors are getting invited to Vatican climate summits, you know the balance of climate leadership is shifting. The C40 Cities is a global network of nearly 100 mayors of the world’s leading cities that are united in action to confront the climate crisis, and Asian cities are increasingly prominent members.
The Equity Challenge Facing Urban Climate Action
Not all climate action is created equal, and cities are grappling with making sure their green transitions don’t leave vulnerable communities behind. We find that among large U.S. cities with CAPs, less than one third include measurable indicators to evaluate progress towards achieving equity goals. Across climate adaptation and mitigation planning, nineteen cities consider equity goals as they relate to ten thematic areas, six outcomes, and five dimensions of equity. This is a huge blind spot that could undermine the entire climate movement. For example, economic risks as a result of climate impacts are not evenly distributed throughout the country—the poorest third of counties in the U.S. are projected to see the greatest income losses by the end of the century (between 2 and 20%) under business-as-usual emissions scenarios. Cities are starting to wake up to this reality, but progress is painfully slow. The stakes couldn’t be higher – if climate action becomes synonymous with gentrification and displacement, it’ll face fierce community opposition.
Climate Adaptation Becoming Cities’ New Priority
While everyone’s been focused on reducing emissions, cities are quietly becoming adaptation powerhouses. According to a recent survey by the European Investment Bank of 744 municipalities, over 60% plan to increase their investment in climate change mitigation and adaptation over the next three years. The writing’s on the wall – or more accurately, the floodwater’s at the door. European cities are adapting to climate change through a wide range of effective actions, including urban planning and building codes, economic incentives and insurance, early-warning systems and information campaigns. Mayors are almost universally aware (84%) of the at-risk sectors in their territories, that they perceive to have the greatest vulnerabilities and are bracing themselves for severe impacts from these hazards across all municipal sectors. Namely, buildings (41%), transportation (31%) and energy infrastructure (24%), were considered most at risk. Cities aren’t just planning for a different future – they’re planning for a more dangerous present.
The Federal-Local Climate Dance in America
The relationship between federal and local climate action in the U.S. is getting more complicated by the day. America’s climate-leading states, cities, Tribal nations, businesses, and institutions will not waver in our commitment to confronting the climate crisis, protecting our progress, and relentlessly pressing forward. No matter what, we’ll fight for the future Americans demand and deserve, where our communities, our health, our environment, and our economy all thrive. This defiant statement from major climate coalitions reveals the growing disconnect between federal politics and local action. All planning grant recipients will also develop Comprehensive Climate Action Plans (due in the second half of 2025 for most grantees), which will include a broader suite of GHG reduction measures from all key emitting sectors – electric power, transportation, commercial and residential buildings, industry, agriculture/natural and working lands, and waste and materials management. The comprehensive plans will also contain GHG emissions projections and reduction targets, air quality and health benefits information, and workforce planning assessments. The federal government is creating frameworks, but cities are filling in the details – and often going way beyond what’s required.
Cities aren’t just filling a climate policy void – they’re creating an entirely new model of climate governance that’s more responsive, more innovative, and frankly more effective than what we’ve seen from traditional nation-state diplomacy. The question isn’t whether cities can lead on climate change – they already are. The question is whether the rest of us can keep up with them.
