Frequently Asked Questions

The Intergovernmental Panel on Climate Change (IPCC) defines CDR as “Anthropogenic activities removing carbon dioxide (CO2) from the atmosphere and durably storing it in geological, terrestrial, or ocean reservoirs, or in products. It includes existing and potential anthropogenic enhancement of biological or geochemical CO2 sinks and direct air carbon dioxide capture and storage (DACCS) but excludes natural CO2 uptake not directly caused by human activities.” (IPCC, AR6).

As climate change progresses, the importance of carbon dioxide removal (CDR) increases in parallel. Reducing greenhouse gas emissions is the number one priority to mitigate climate change, but CDR is necessary to reach net-zero emissions and become carbon neutral. Any city with a net-zero target is expected to need CDR to accelerate climate change mitigation and balance residual emissions from hard-to-abate sectors.

The City CDR Initiative is a non-profit multi-year effort with a mission to durably embed Carbon Dioxide Removal (CDR) in urban planning around the world. It aims for cities to have a complete strategy to reach net-zero, grow the CDR sector by adding fresh CDR demand and supply, and increase the chance of meeting global climate goals.
Through its capacity building approach, the Initiative will help cities realize existing priorities through CDR projects and equip city officials to identify opportunities and design policies that maximize synergies. It uses a definition of CDR and an approach to CDR that is tailored to the political economy of cities and has buy-in from cities and other stakeholders.

Intended outcomes:

• Empowered leadership: A global movement of mayors is activated to drive sub-national action and engage their national governments to promote CDR policies.
• New narratives: ‘Front yard’ narratives and messages are developed that enable pitching CDR beyond its sustainability credentials, in general and towards local citizens.
• Fresh demand signals: Cities are incentivized to include CDR in climate plans as part of residual emissions strategy, local compliance schemes, and procurement efforts
• Novel supply options: CDR deployment advances inside and outside city boundaries, including through embedded CDR in urban systems and urban CDR project designs.

The idea for the City CDR Initiative originated as a result of a study commissioned by the City of Amsterdam to Swiss climate consultancy South Pole and Norwegian non-profit Bellona in 2022. The municipal government requested an assessment of the potential for CDR in and around the city to learn how it could contribute to its climate targets. The study highlighted a potential of over 1 Mt/CO2 p/a that could be removed, based primarily on the potential to apply carbon, capture and storage technology to existing biogenic emission points.
The authors had now learned the immense global potential for CDR in the urban environment and the opportunity for cities to play an important role. The authors of the study engaged a dozen cities with a net-zero target to learn why they had not developed any meaningful carbon removal policies. The feedback highlighted a lack of capacity and funding, as well as a persistent belief that CDR can be postponed until the year of the net-zero target. The authors quickly realized that municipal governments could not be convinced to pursue CDR for climate’s sake alone.
Over the course of 2023 and 2024, a new narrative was developed for what was called ‘City CDR’. According to the initiators, City CDR refers to all initiatives and strategies taken by cities to actively reduce CO2 levels in the atmosphere. These initiatives are driven by local governments, often in collaboration with various stakeholders including businesses, NGOs, research institutions, national governments, transnational municipal networks, and citizens. City CDR aims to mitigate climate change by removing CO2 from the atmosphere, while maximizing synergies with wider city priorities.
Along the way, the idea for the City CDR Initiative was born. An informal consortium was created to find ways in which cities can be equipped and empowered to support CDR while realizing existing social, economic and environmental urban priorities. The aim of the effort was to understand how city officials can be equipped and empowered to identify opportunities and design policies which promote carbon removal projects and deliver on climate adaptation and resilience, energy transition, biodiversity promotion, air pollution reduction, job creation, social equity, innovation, and/or local municipal revenue generation.

The project continues to baseline the opportunity of City CDR. It is aimed at identifying and providing initial support to the vanguard of cities that will be receiving individualized technical assistance under Phase 2. The project will support cities by:

• Assessing the most promising CDR approaches for urban deployment across key metrics and identify opportunities for municipal support;
• Identifying cross-policy linkages and GHG accounting approaches;
• Establishing a basis for advocacy and awareness raising activities; and
• Developing a project assessment framework for CDR projects and city-level action.

By identifying opportunities for CDR in and around urban environments, mapping the modalities of specific project value chains, assessing synergies with other city priorities, and advocating for CDR by cities, cities will:

• Learn how to embed CDR in city climate actions and urban planning;
• Have technical and financial blueprints of CDR interventions at their disposal;
• Be empowered with the frameworks needed to prioritize interventions for CDR;
• Have access to city-specific accounting rules for carbon removals; and
• Be ready to advance CDR deployment and develop the tools to facilitate pilot projects.

As a result, cities will be a step closer to advancing CO2 removal projects and generating negative emissions. They will be able to access the necessary knowledge and tools to develop a more complete climate strategy to reach net zero and become net negative, in which CDR is implemented without cannibalizing other city priorities and scarce resources.

There is institutional momentum behind sub-national climate action, including municipalities. Existing frameworks, such as the 1,145 cities and local governments in the Cities Race to Zero and the 112 cities of the EU 100 Climate Neutral Cities by 2030 Mission, are ripe for the adoption of CDR. After all, without CDR, cities cannot reach net zero.

Cities hold immense potential to scale global carbon removal, both as agents and as areas:

• • City as Agent of Change: Municipal governments are on average the most powerful public governance layer after national governments and can pursue systemic policymaking. Their vicinity to citizens (voters) makes them ideal pilot grounds.

>

• City as Area for Deployment: The urban environment holds massive potential for CDR. A first of a kind global assessment published in Nature estimates it upwards of 1 Gt/CO2 p/a. This covered only a few CDR methods and is likely to be significantly higher.

Moreover, CDR projects in the urban environment can help support urban priorities across climate adaptation and resilience, energy transition, biodiversity promotion, public health, air pollution reduction, job creation, social equity, innovation and local municipal revenue generation. This ‘multiplier effect’ is where the opportunity lies for city governments.

Urban CDR refers to carbon removal projects and technologies that are deployed within municipal boundaries and result in the capture and/or sequestration of biogenic or atmospheric CO2. Storage may be temporary (several decades) or durable (several centuries). Examples include Biochar + embodied carbon in buildings; Biochar + food waste/garden waste; Biochar + sewage sludge; Direct Air Capture (DAC) or BioCCS + mineralized storage in cement and concrete; DAC + HVAC in buildings; Forestation within cities; Improved land management practices; Urban wetlands restoration; Enhanced Rock Weathering (ERW) + rooftops and urban pathways; ERW + landfill; Carbon negative concrete + coastal fortification; surficial mineralization + gravel for roads and parking lots; Ocean Alkalinity Enhancement (OAE) + desalination; AE + municipal wastewater; BioCCS + waste to energy plants.

Across the landscape of CDR methods, there are many project types that simultaneously remove carbon and lead to GHG reductions, climate adaptation, biodiversity improvement, air pollution reduction, soil quality improvement, as well as enabling local industrialization, creating new municipal revenue sources, attracting investment, and talent. The Initiative aims to identify such opportunities and recommend cross-policy approaches to unlock them.
Of particular relevance are synergies with resilience and adaptation.

Examples are:

• Heat stress: shade increases with urban forest coverage that also creates sinks to sequester CO².
• Water stress: water retention improvement with regenerative agriculture practices that also sequesters CO².
• Coastal erosion: coastal fortification with bulk materials and enhanced rock weathering that also permanently sequesters CO².
• Flooding: flood protection with wetland restoration that also enhances sinks to sequester CO².
• Ocean acidification: adding alkaline substances to seawater that counters acidification and also creates bicarbonates and carbonates that permanently store CO².
• Soil depletion: adding biochar to land to increase soil fertility and soil moisture and also permanently sequester CO².

Cities are invited to co-design the capacity building program intended for Phase II, as well as providing direct input into the designs of Phase III and Phase IV. Although nothing has yet been agreed on the organization of the program, an expected step is the establishment of a dedicated non-profit entity and organization structure to manage the program over time. This may hold a leadership board of rotating cities that contributes to shaping the strategic agenda of the City CDR Initiative.

The remainder of 2025 is expected to focus on concluding the baselining phase. This includes the current project for which we are asking cities to participate. Other foreseen activities that still require funding include a 2-day in-person policy hackathon and a concluding event during New York Climate Week (NYCW) in September. We are further envisaging a mobilization event at COP30 as a step towards Phase II.

Conditional upon successful fundraising, our ambition is to announce the City CDR Initiative Phase II and the 8-10 Anchor Cities at COP30 in Brazil. This will kick off a process of establishing the organization and designing the three core pillars for Phase II: Technical Assistance Facility; Learning, Exchange and Advocacy Platform; City Advisory Resource. Phase II is expected to last for an initial two years during H1 2026 and H1 2028.

A Phase III is foreseen to focus on catalyzing public and private sector investment into urban CDR projects. Targeted funding mechanisms are expected to be created such as a City CDR Trailblazer Prize, Urban CDR Project Competition, Urban CDR Public Procurement Platform, and Urban CDR Impact Fund. Work on designing this phase is due to commence in 2026.

The future of the City CDR Initiative after the initial three phases (post-2028) remains to be defined. It will likely aim at institutionalizing the capacity building work in the standard programming of existing leading city networks, such as C40, GCoM, and ICLEI. The Initiative may then become a Global Expertise Center providing technical assistance, research and advocacy, while managing the Impact Fund and Procurement Platform as subsidiaries.