While The World Waits For A Real Climate Deal, Megacities Are Taking Action


Cities may be responsible for 70 percent of the world’s carbon emissions, but they are also moving faster than ever to cut them, according to C40, the global climate leadership group for the world’s largest megacities.

The former mayor of New York City, Michael Bloomberg, and the current mayor of Rio de Janeiro, Eduardo Paes, released the new draft of the Climate Action in Megacities 2.0 report, spelling out exactly how the world’s largest metropolises are cutting greenhouse gas emissions and improving urban resilience to climate change. Paes, still settling in as Chair of C40 after Bloomberg became President of the Board back in November, leads a consortium of 63 of the largest cities on the planet taking action to address climate change. These cities represent 600 million people worldwide.

In the two years since the previous survey, responding cities have doubled the number of steps they’re taking to address climate change to a collective total of 8,068. These actions range from low-carbon transportation options to building efficiency improvements, lighting upgrades to waste management — but adapting to climate change tops the list for most.


Here are concrete actions individual cities are making to address climate change:

Adapting to the climate change already happening. 98 percent of respondents said climate change presents significant risks to cities. Flooding, extreme heat, threats to bio-diversity, stormwater — all of these are of serious concerns to urban dwellers. London’s “Drain London” project has produced detailed floodmaps for each neighborhood, and its Thames Estuary 2100 program assessed how to protect the city against 4 meters of sea level rise. Chicago focused on converting pavement to more permeable surfaces through projects like green alleys. Philadelphia plans to replace a third of its impervious surfaces by 2029. Washington, D.C. focused on allowing for quick detection of water pipe leaks, while Mexico City reduced leakage losses along 795 km of old pipes.

Recycling on a huge scale. Reducing waste makes the economy more efficient and retains value while lowering carbon emissions. Buenos Aires is diverting 1,500 tonnes of construction waste from landfills with its first treatment plant devoted solely to that task. Vancouver is taking recycling to a new level by hosting a “deconstruction hub” that allows builders and residents to reuse materials deposited by people who do not want them anymore. Chicago is piloting a program that weighs the amount of recycling material from each household, earning points redeemable at local businesses. Houston requires residents to place plant and tree trimmings in a separate compostable container. Milan now requires its garbage and recycling trucks to use 20 percent biodiesel.

Moving people around with less pollution. People driving their own cars rather than taking public transit, cycling, or walking causes traffic — but it also leads to an outsized role in carbon pollution.


On the left, the “modal share” means how many trips are made by bus, rail, car, taxi, walking, etc. — which compares to the right column showing how much each of those transportation types contribute to CO2 emissions. Private motorized transport (in most cities, cars) provides less than a third of all trips, but leads to 72 percent of all CO2 emissions.

C40 cities address this by: restricting parking, promoting car sharing, promoting walking, increasing tolls or fees, and promoting electric vehicles. Efficient bus and rail expansion also topped the list.

Paris shrank available parking by 9 percent, and started charging for 95 percent of the formerly free spots. The French capital now has 20,000 bikes and 1,750 electric cars in two fast-growing bike- and car-sharing systems. Oslo has lowered many barriers to make its goal of converting its city-owned car fleet to an electric one by 2015 achievable — including installing 200 new charging stations per year, waiving the VAT, making public charging free. Philadelphia is switching from individual parking meters to centralized kiosks, and then switch old parking area to bike parking. Overall, bike sharing systems have increased six-fold, and 80 percent of member cities had implemented bike lanes by 2013.

Caracas focused on modernizing its bus system to make it more efficient. Rio de Janeiro is expanding its metro system and making it more energy-efficient. Warsaw is purchasing 168 tram cars that recover energy from braking — and now has 340 km of bike paths. Venice even bought 17 low fuel consumption ferry boats.

Using less energy to do more. Energy efficiency seems low-hanging fruit to many C40 cities, representing 20 percent of all activities across all sectors. Ninety percent of respondents reporting action on efficient outdoor lighting. Promoting building efficiency — mainly through better insulation and efficient heating and cooling — was also a focus. These actions were focused in Asia and North America. Wealthier cities led the way in LED lighting projects, but large cities regardless of wealth found building efficiency actions feasible. Sydney, Australia was singled out in the report for a particular focus on building efficiency:

Sydney is retrofitting 45 of its major municipal buildings with energy and water savings measures. The retrofit will cut energy use by 6,641 MWh (megawatt hours), reducing greenhouse gas emissions by 23% per year and water consumption by 53,313 kJ per year. The city’s payback period on investment is estimated to be within nine years of project completion.

Sydney is also replacing three-quarters of city-owned lights with efficient ones, cutting GHG emissions by half and saving AU$800,000 per year.

Switching to low-carbon energy. Twenty-four of the C40 respondents have direct control over their municipal power supply, and many reported taking action to introduce renewable energy generation into the mix. Solar photovoltaic led the way, followed by solar heating, and anaerobic digestion. Portland, Oregon generates 7.9 percent of its total municipal energy use from two turbines powered by anaerobic digestion. Mexico City is beginning to use biogas from the Bordo Poniente Landfill. Oslo will have converted all of its district heating to renewable energy by 2016, even recovering waste heat from data centers.

In addition, many C40 cities are making the switch to lower-carbon electricity and heating fuel, mainly by purchasing green electricity from the grid and switching from heating oil to natural gas.


There is definitely room for improvement. Just 23 percent of proposed actions in 2011 were implemented citywide by 2013, across most of the city, or became a pilot program — while 77 percent either were not continued or stayed proposals. A similar percentage of pilot programs in 2011 turned into reality by last year.

“Cities account for 70 percent of the world’s carbon emissions, and three-quarters of the world’s energy use,” Bloomberg told reporters on Tuesday. “So the actions they take today to confront climate change really will have a global impact.” Bloomberg trumpeted cities as being uniquely capable of taking action to mitigate and adapt to climate change when compared to a national government’s.

Asked what he would tell a suburban or rural mayor who may not have the resources or influence of a megacity mayor but who wanted to take action to address climate change, Bloomberg said, “mayors, even if they don’t have the authority granted by the legislature, the public looks to mayors to deliver services.”

He went on to explain how even if a smaller mayor does not have the authority to take large actions, people listen to them, so when they go to legislatures, they can often have more influence than people would expect.

Last week, Bloomberg became U.N. Secretary-General Ban Ki-moon’s special envoy for cities and climate change. He said Tuesday that he can help Ban make the case that taking action on climate change can be simple and not cost a lot of money.

“There’s nothing inconsistent between what we do at the city level and what he would like to get done at a national level,” he said.