Changing Planet

Dispatch from Rio: C40 Mayors Demonstrate Progress in Greenhouse Gas Reductions and Announce New Actions to Take on Climate Change

C40 Chair New York City Mayor R. Bloomberg, President Clinton, Rio de Janiero Mayor Paes and 33 C40 Cities announced last week several key developments advancing the measurable actions cities are taking to combat the impacts of climate change. The group was convened at the Rio+C40: Megacity Mayors Taking Action on Climate Change event, which sought to influence the state-level negotiations taking place at the Rio+20 UN Conference on Sustainable Development in Rio de Janiero, Brazil.

During the opening ceremonies of the Rio + C40 event, Mayor Bloomberg announced that – based on recent research — C40 Cities’ existing actions will reduce annual greenhouse gas emissions by 248 million tons by 2020; while collective actions of C40 Cities have the potential to reduce greenhouse gas emissions by over 1 billion tons by 2030.

Addressing the global community of government leaders, experts and citizens, Mayor Bloomberg said:

“Mayors and cities don’t have the luxury of just sitting around and talking about problems because on a whole range of critical issues, the buck stops at City Hall. Because of Mayors’ commitment to action, cities are making great progress in reducing greenhouse gases, which helps beat back climate change and makes our cities better, more liveable places. The data we are releasing today is more evidence that cities have been and will continue to lead the way.”

C40 also announced two new initiatives to continue to drive collaboration and knowledge-sharing among C40 Cities. The first is the launch of a Solid Waste Network in partnership with the World Bank and the Climate and Clean Air Coalition to help cities reduce methane emissions through solid waste management. The second initiative announced a new partnership between C40 and the Joint Initiative on Urban Sustainability (JIUS) to create an online platform that will enable cities around the world to share best practices by creating a global library of case studies. This will be added to the newly launched and highly acclaimed website:

The gathering of C40 Cities last week on the eve of the Rio+20 conference was a powerful reminder of the impact global cities are having in addressing the impacts of climate change.

To learn more about each initiative click here or watch the video of the opening ceremony above.


The C40 Cities Climate Leadership Group (C40) is a network of large and engaged cities from around the world committed to implementing meaningful and sustainable climate-related actions locally that will help address climate change globally. Recognizing that cities consume over two-thirds of the world’s energy and account for more than 70% of global CO2 emissions, our organization’s global field staff works with city governments, supported by our technical experts across a range of program areas to reduce carbon emissions and increase energy efficiency in large cities across the world. The current chair of the C40 is Rio de Janeiro Mayor Eduardo Paes, and 108th Mayor of New York City Michael R. Bloomberg is President of the Board. The Steering Committee includes: Berlin, Buenos Aires, Copenhagen, Hong Kong, Houston, Jakarta, Johannesburg, London, Los Angeles, Rio de Janeiro, Seoul and Tokyo.
  • kaj embren

    Mayors need to take the lead and push national goverment for actions. Smart regulations, incentives and barriers for the once who work with fossil fuels and Green Procurement policies. Cooperation and networking with Mayrors as a plattform for actions. Read more at

  • […] In this context, it’s interesting to note the remarks of Romeo Pascual, Los Angeles Deputy Mayor of the Environment, at the Base Cities London conference recently. Deputy Mayor Pascual had just returned from the Rio+C40 Cities meeting. In contrast to what many believe to be the relatively weak agreement signed by national leaders at the Rio+20 meeting, he said that he and his colleagues had been united in their resolve to take strong action to lead cities towards sustainable growth. […]

  • […] to establish serious commitments from federal governments toward sustainability, the C40 has been cited as a success story. UN Habitat, the International City Managers Association, and the New Cities Foundation have varied […]

  • […] But cities increasingly are. Federal governments weren’t able to come to agreement on how to address climate change with the Kyoto Protocol or at Rio+20, but the C40 — a coalition of cities addressing climate change — is cited as a rare success story of international collaboration. […]

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