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By 14 June, 2017February 24th, 2020No Comments


It has been said of the outcome of the UN Climate Change Conference COP21 in December 2015 held in Paris that ”By comparison to what it could have been, it’s a miracle. By comparison to what it should have been, it’s a disaster”.

It goes too far to suggest that last year’s historic agreement on climate change is a disaster, but George Monbiot, who is the author of the comment above, has a point in that a major issue is still outstanding. The agreement has set an ambitious goal of limiting global temperature increases to a maximum of 1.5 degrees, and it has created an unprecedented political consensus on combating climate change. However, the agreement contains few indicators as to how the goal is to be realized and lacks clear commitments on funding. There is still uncertainty about how the agreement as a whole is to be implemented. Inspiration may be garnered from more than 80 of the world’s largest and most innovative cities, which through the C40 city organization have found an effective model of cooperation with a focus on climate actions rather than declarations. For over 10 years the so-called mega cities like New York, Rio, London, Kolkata and Beijing have inspired each other through C40’s global city network to implement initiatives on climate change and exchange experiences on how such initiatives can be implemented at street level in the best and least expensive way. Since 2009 when COP15 was held in Copenhagen, it has resulted in more than 10,000 CO2-reducing climate actions, of which over a third have been directly inspired by examples that C40 cities have learned about through cooperation with other cities.


And there are many signs that this is just the beginning. C40 cities together account for over 25 per cent of the world’s GDP and, as a collective player, have a significant potential to further reduce global CO2 emissions. A detailed analysis of C40 cities’ climate actions in the period between 2011 and 2015 has shown that there is still potential for 27,000 new initiatives on climate change. If, in the coming years, cities implement the approximately 2,300 initiatives that the analysis shows can be realized in the easiest and fastest way, the potential for further CO2 reductions in C40’s cities is on a par with the UK’s total annual emissions. For each of these initiatives, there is typically a need for companies to develop plans, deliver technologies and be responsible for their implementation. The C40 city collaboration also creates obvious opportunities for partnerships with the private sector and for leading cleantech companies to contribute to the realization of the thousands of planned climate solutions. Through C40, green companies stand to raise the profile of their most successful projects and good solutions can quickly and efficiently be propagated through C40’s global network.


We often think of cities as competitors to attract businesses, jobs and talents. In the days immediately following the Brexit referendum, London was full of colourful advertisements from the Berlin city administration inviting disappointed London-based ’start up’ companies to settle in the German capital. With imaginative international campaigns and slogans, cities can position themselves in an international field, where the aim is to make themselves appealing and attract global investment faster and better than their neighbours. When it comes to climate change, the image of the competing cities has several facets. Mayors are faced with identical and often acute challenges to prepare for a rapidly changing climate. For historical reasons, the world’s cities frequently have their genesis in ports and estuaries and are thus vulnerable to storm surges and rising sea levels.


“As mayors, we face similar challenges and we must all be innovative to nd solutions. The C40 network allows us to collaborate and share ideas so that we can work together towards a greener and healthier future” (Anne Hidalgo, Mayor of Paris.)

Over two thirds of C40’s cities report that they already have to adapt to the consequences of climate change and demand effective solutions to create more resilient cities when climate-related crises occur. As the comment of Paris Mayor, Anne Hidalgo, suggests, city leaders are on the lookout for the best and most feasible ideas and see only advantages in borrowing from a colleague if a particular solution has proved effective and easy to realize. Thus, the C40 mayors are part of a friendly and productive competitive relationship, where they both seek to establish their leadership in the global climate arena through the implementation of spectacular and innovative climate solutions and through the formulation of the most ambitious and far-reaching climate action plans. It has attracted international attention, for example, that Copenhagen, with its goal of becoming CO2 neutral by 2025, probably has the world’s most ambitious climate plan. On the other hand, cities make detailed knowledge of their climate solutions available to colleagues through the C40 network and look to each other to find and copy the best ideas. A good example is New York, which in recent years has paved the way for the Confederation of Danish Industry in partnership with the City of Copenhagen and a number of companies, to establish a Clean- tech hub in Manhattan. Specifically, this has resulted in concrete cooperation centered around Copenhagen’s climate adaptation plan.

At first sight it might appear unlikely that New York would invite a competing city and Danish companies in, but the Danish hub gives New York easier access to the critical expertise that these companies represent. This then creates the platform for local New York businesses to enter into new collaborations with Danish partners and create new business opportunities. Other cities have been inspired by the idea, and Copenhagen is currently working with others, including Washington DC on a similar partnership. One of the reasons that competing cities come together in a mutually trusting and productive collaboration on climate solutions is that C40 is a mayor-driven organization. The management of C40 is a steering group, which in addition to the chairman has 12 mayors who make the decisions on the organization’s strategic direction. Frank Jensen is Vice-Chair of C40’s steering committee for Copenhagen and representative of C40’s 16 innovation cities that have a place in the C40 network because of their exceptional results in the eld of sustainable urban development. The steering committee is chaired by alternating mayors – with the Mayor of Paris, Anne Hidalgo, succeeding Rio’s Eduardo Paes as Chair. Cities do not pay a subscription fee to be a member of C40, but have to meet a number of requirements, including active participation and achievement of certain standards in the climate change field. C40 is financed by a number of philanthropic organizations with Denmark’s Realdania as one of its three strategic contributors.



The best inspiration for a mayor is from another city leader, who has already solved the problem.

C40’s collaboration model rests on a strong commitment from urban mayors and ideas being frequently exchanged between C40 cities, because a mayor or senior executive has been inspired directly as a result of a meeting with a colleague. Examples include when Ho Chi Minh City in Vietnam, which needed to protect itself against rising sea levels, reached out to Rotterdam and received advice from Rotterdam’s climate adaptation plans; or when Kolkata and Yokohama launched a partnership to develop solutions in the waste management area or when Portland sought help from Johannesburg to develop green bonds to nance new climate initiatives. To accelerate the exchange of best practice examples from cities, C40 operates with a number of networks in areas such as energy, waste, transport, water and green growth, where technical staff in the cities can advise each other. The philosophy behind these networks is that the most useful and effective advice that a city employee can get is from a colleague in another city that has been through a similar process. And as some illustrative examples demonstrate, this model can have a powerful effect. For example, the number of cities that use energy-saving LED street lighting has grown significantly over a short period, from approximately 50 per cent of C40 cities in 2011 to 90 per cent in 2013. And, in the same time-frame, there is a similar example involving the so-called Bus Rapid Transit system model; the number of cities that have implemented this for public transport has grown from 13 to 29 in just two years. The C40 model is based on cities’ ability, and their prioritization of it, to share their experiences openly with other cities. A high level of activity is essential for the model’s success. C40 cities have agreed on a set of minimum standards for their activity level, so it is worthwhile for all of them to contribute actively to the network. C40 cities further undertake to develop ambitious quantifiable targets and specific plans to reduce CO2 and use the same UN-recognized method to keep accounts of their CO2 levels and report this to the C40 network every year, so that there is transparency concerning C40 cities’ progress on climate change and reaching their CO2 reduction targets. This data-driven approach allows C40 cities to implement and highlight the collective progress on CO2 reduction, while C40 maintains the flexibility and avoids highly descriptive models for how more than 80 cities with different resources and back- grounds should act in relation to climate change. Cities can follow different objectives and strategies, but all must apply the same standard to measure the effect of their actions in order that they should be comparable.



It is standard for the majority of C40 cities to have a practical approach to climate change in terms of creating solutions that work in daily life for their citizens, and which are good for the economy. New York’s former mayor, Fiorello La Guardia, famously observed ”there is no Democratic or Republican way of fixing a sewer”, and this frequently applies to C40 cities in that their efforts for a better climate stem from a practical concern to create green growth and quality of life for their citizens, rather than from ideology. For this reason, climate work in C40 cities is often driven by the ambition to develop green growth models that create jobs while reducing CO2. In this regard cities look for close cooperation with companies and research institutions that are able to deliver practical solutions and develop new green business opportunities. It would be intuitive to think that economic growth usually goes hand in hand with higher CO2 emissions, because the demand for fossil fuels grows with the increased economic activity. However, under the auspices of the Global Commission on the Economy and Climate, it has been demonstrated that innovative cities can achieve economic growth while reducing CO2 emissions. C40 cities like Copenhagen, Stockholm and Portland, for example, have achieved CO2 reductions of up to 40 per cent over the past 25 years, while economic growth has been equally significant. The objective of these cites is that th-rough innovative climate solutions, they create a platform for the export of such solutions to other cities; and that with the C40 network as a platform, they can create maximum visibility for their most successful climate initiatives. This creates opportunities for those companies that have helped to develop and implement the solutions.

A striking example of this dynamic is the Copenhagen climate change adaptation plan and demonstration district at Skt Kjelds Kvarter in Østerbro, which has been studied by other C40 cities. The result being that New York this year has reached an agreement with the Danish consultancy, Rambøll, to develop a similar strategy for climate security in Manhattan. C40 cities also see great opportunities in collaborating more directly with private stakeholders on the development of new solutions in the climate change area. This is particularly where there are complex issues, and where cities lack insight into what opportunities are technically available on the market. Collaborations between cities and companies can be complicated and involve risks of conflicts of interest in relation to competition and tendering regulations. At worst companies in any subsequent tender process can be excluded from participation in an actual project. In the EU, good opportunities for various forms of dialogue prior to tendering have gradually emerged, but globally, almost 15 per cent of the C40 cities perceive tender regulations as a major barrier to implementing climate projects in cooperation with private players. With the ’City Solutions Platform’ project, C40 wishes to address this barrier in collaboration with Realdania, the Danish cleantech organization CLEAN and a number of companies, including Danfoss, Hitachi and RTI. The project allows selected cities with complex challenges in the climate area to enter into cooperation with a selected consortium of international and local clean-tech companies and research institutions to jointly develop new, innovative solutions to the city’s challenges. The idea is that cooperation takes place at a much earlier stage of project development. Companies should be invited into the phase where the city has not yet defined the solutions needed to solve a problem. And when the city is seeking advice from private players who have a better understanding of the opportunities and limitations of existing technologies. The project is currently in a pilot phase in which 4-6 cities will test the working method and the idea along with a number of partners from the private sector. The ultimate objective is the implementation of specific projects in each of the participating C40 cities, thus demonstrating the strength in cities, companies, research institutions and other parties coming together at a much earlier stage in the cities’ project development to develop new solutions to climate challenges.


The Paris agreement is a historic one that creates a global consensus around the target of a maximum temperature rise of 1.5 degrees celsius above pre-industrial levels. When the C40 cities meet in Mexico City in late 2016 for their great mayor summit, which takes place every two years, it is with an agenda to provide a signicant contribution to realizing the Paris Agreement and a climate-secure world.

Time is short – and calls for a swift journey from declarations to action. If the world is to achieve the Paris agreement’s objectives, it requires that global CO2 emissions will have peaked by 2020. The Paris agreement comes formally into force in 2020, so leadership is needed in the fight for a CO2-neutral and climate secure world. Cities have the political and economic potential to make a difference, but are also the source of a great proportion of the world’s CO2 emissions. The world’s mega-cities are continuing to grow, and it is expected that 70 per cent of the world’s population will live in them by 2050. C40’s research has shown that cities’ decisions on infrastructure over the next five years alone can account for up to a third of the CO2 emissions that the world can afford to emit until the pain threshold is reached. But, among other things, by virtue of their C40 commitment, cities are showing that they are prepared to deliver a significant contribution to reducing global CO2 emissions; and through C40 they have defined common standards for their climate efforts. The C40 cooperation accelerates the spread of the most effective climate solutions across geographic and economic boundaries. When competing on climate change, clean air, clean energy and quality of life are the parameters that count. Cities alone cannot deliver the technology, infrastructure and know-how required to realize their climate plans. They work actively with private players on the development and implementation of urban solutions, creating diverse business opportunities and new markets for leading clean-tech companies as well. In other words, the world’s mega cities are part of the climate problem – and the solution. In many ways it is here that the battle for the climate’s future will be won or lost. With the C40 partnership, the world’s largest and most innovative cities have accepted the challenge themselves, and act together in order that the urban world will be a greener, healthier and above all climate safe place to live and grow up.


Simon Hansen is C40 Director of Regions and part of the organization’s global leadership. He handles the management of C40’s regions and cities team. C40 was set up in 2005 as an organization for the world’s mega cities with a focus on the exchange of best practice examples in the climate field. It has 86 cities as members and they account for over 650 million inhabitants and around 25 per cent of world GDP. C40’s member cities are found in every region across the world. Copenhagen is a member of C40 as one of its 16 so-called innovation cities.

This article was originally printed in the magazine Udenrigs that is published by The Danish Foreign Policy Society. This special issue on global urbanization was published in relation to the conference Urbanization and Exports that was hosted by Realdania and The Danish Foreign Policy Society.

Image credit: Emilie Koefoed