Welcome to City Solutions!

Welcome to the City Solutions blog, presented by the C40 Cities Climate Leadership Group (C40), a network of the world’s megacities that are a leading force for global action on climate change. The C40 is chaired by New York City Mayor Michael R. Bloomberg.

Why cities? Urban sustainability is arguably the defining concept of our time. The confluence of several facts and factors has made this so. In 2011 the world’s population surpassed 7 billion; and, for the first time in history, more than half of the world’s population now lives in cities. At the same time, cities are on the frontlines of climate change, responsible for 70 percent of global carbon emissions; and yet increasingly vulnerable to climate risks and impacts.

Today we see cities forging ahead, implementing tangible local actions — and sharing these solutions.  New York, Sao Paulo, London, Tokyo and Jakarta are just some of the cities within the C40 network who are getting on course for long-term sustainable growth.

Through the City Solutions blog, we hope to engage you in discovering how cities are making real progress, but also continue to face real challenges. We will share news, stories, as well as the voices of Mayors and other leading experts from around the world who are focused on the particular issue of cities and the solutions they offer.

From now until June, we’ll be on the road to Rio+20, the United Nations Conference on Sustainable Development, looking at the issues through the lens of cities, and calling for cities to be at the top of the agenda.


Michael V. Marinello
Managing Editor, C40 Cities Live blog

Follow @C40Cities on Twitter or “Like Us” on Facebook to learn more about how cities are taking action to provide solutions for climate change.

Changing Planet


Meet the Author
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.