Linda Poon is a staff writer at CityLab covering science and urban technology, including smart cities and climate change. She previously covered global health and development for NPR’s Goats and Soda blog.
As mayors gather for C40’s summit on climate change, the coalition reports that a third of its members have hit peak emissions.
Since nations signed on to the Paris Agreement four years ago, committing to collectively lower carbon emissions to below 2 degrees Celsius, progress across the globe has been uneven and, sometimes, even discouraging.
But there is good news. Austin, Athens, Lisbon, and Venice have joined 26 other major cities in steadily reducing their greenhouse gas emissions, according to a new analysis published by a coalition of cities known as C40, ahead of its World Mayors Summit in Copenhagen. The latest news is an update to C40’s 2018 analysis, which identified a handful of cities across the global north that have hit their “peak” emissions before 2015, meaning they have since reduced their greenhouse gas emissions by at least 10 percent.
All together, the 30 cities represent some 58 million urban citizens. They also make up a third of C40’s 94 members, which spread out across all continents (excluding Antarctica). A few smaller member cities in China and in lower-income countries have also hit peaks, though a thorough analysis of those won’t come out for a few years, according to Michael Doust, C40’s program director of measure and planning.
On average, the 30 cities identified by C40 have curbed emissions by 22 percent. Some of the most significant reductions came from London, Berlin, and Madrid, which averaged around 30 percent reductions, while Copenhagen lowered emissions by a dramatic 61 percent. Granted, when Copenhagen hit its highest emission levels to date in 1991, it was only releasing 4 million tons of emissions, compared to, say, the 50 million tons from London in 2000.
“But the key thing is that Copenhagen just shows that it is possible to rapidly decarbonize over a short period of time,” says Doust. “And the innovations they are applying are applicable globally.” A key contributing factor to the city’s success is the expansion of its district heating system, which channels waste heat from electricity production through the pipes into homes to meet the demands of an increasing population.
At the same time, it invested heavily in its biking infrastructure and public transit. Indeed, Doust says investments in transit, building energy efficiency, and switching fuel to zero-carbon energy sources are some of largest drivers among the cities.
Among the 30 cities, Tokyo stands out not only for being the only non-Western city, but also for the fluctuations in its yearly emission levels. They began falling after 2003, but by 2010 levels rose again, reaching near-peak levels by 2012 and 2013. Yet Doust assures us that Tokyo is an example of a unique success story; emissions began falling again in 2014.
In March of 2011, a massive tsunami triggered a disaster at the Fukushima nuclear plant, prompting Japan to shut down all its working nuclear reactors as part of a safety drive. That left the country with no nuclear-generated power, and drove up the carbon intensity of electricity as the country switched over to fossil fuel.
“That's now being being reversed again,” Doust says, as the country ramps up its energy-saving policies. Tokyo introduced the world’s first city-level cap-and-trade program in 2010, focusing on urban buildings. By 2016, energy consumption fell 21 percent below 2000 levels, according to C40. And government and Cornell researchers found that the city reduced emissions by over 20 percent.
It’s still possible for any of the 30 cities to once again see emissions rise beyond its highest levels in the future, even as C40 describes them as “peaks.” So far, none has, and to ensure that there aren’t any “false” peaks in their data, Doust says researchers put in that 10 percent reduction threshold as a requirement. “It builds in enough of a buffer zone so that if there is extreme weather—if there's a really cold winter and a really hot summer—those emissions won't rise beyond the peak,” he says.
On a global scale, there’s a lot left to do. C40 mayors are gathering today, just three months shy of 2020, the “climate turning point” set by the United Nations for when the world must reach peak emissions to prevent irreversible consequences. In 2017, the UN launched Mission 2020, laying out six necessary milestones involving radical changes to various sectors, including energy, transportation, and land use.
A sobering analysis from the World Resource Institute suggested that the world has made “insufficient” progress on those milestones. And with global emissions continuing to rise, the world is on course to miss the 2020 deadline. In fact, global energy-related emissions rose to 33.1 billion tons in 2018 and hit a record high, according to estimates from the International Energy Agency. The rise was most dramatic in Asia, where China’s emissions rose by 2.5 percent and India’s by 2.5 percent. The U.S.’s rose by 1.2 percent, while Europe’s continues to fall.
Among the initiatives at this year’s summit, mayors announced their support for a Global Green New Deal, which calls for putting climate action at the center of urban decision-making and cutting global emissions in half by 2030 to avoid the worst impacts. Los Angeles mayor Eric Garcetti will lead the coalition as its new chair, according to a press conference this morning, succeeding Paris mayor Anne Hidalgo who has led the group for the past two years.
Doust argues that within the global picture, the successes of these 30 mostly global north cities are still worth celebrating—if cautiously. “It is expected that these cities should peak before 2020, and the fact that they’re doing so is encouraging,” he says, adding that when cities in the global north peak first, it allows more time for those in developing countries to reach their emissions goals.
It also gives C40 researchers confidence that half of its 94 members will hit peak emissions by 2020. “Overall, it's a very encouraging signal that yes you can still grow your economy, you can still grow your cities in size,” he says, “and still peak.”
The 30 cities are: Athens, Austin, Barcelona, Berlin, Boston, Chicago, Copenhagen, Heidelberg, Lisbon, London, Los Angeles, Madrid, Melbourne, Milan, Montréal, New Orleans, New York City, Oslo, Paris, Philadelphia, Portland, Rome, San Francisco, Stockholm, Sydney, Toronto, Vancouver, Venice, Warsaw, and Washington, D.C.
CORRECTION: This story has been amended to clarify that the World Mayors Summit is not annual.