Tokyo's Governor Yuriko Koike, Los Angeles' Mayor Eric Garcetti, Paris' Mayor Anne Hidalgo, New York's Mayor Michael Bloomberg, Barcelona's Mayor Ada Colau and Milan's Mayor Giuseppe Sala pose during C40 Cities Climate summit in Paris on Oct 23, 2017. (PATRICK KOVARIK / AFP)
BONN, Germany – Mayors from 25 cities around the world, representing 150 million citizens, pledged on Sunday to cut their carbon emissions to net zero by 2050, while boosting efforts to become more resilient to extreme weather and other pressures linked to climate change.
African cities are playing a leading and decisive role in delivering on the ambition of the Paris Agreement
Anne Hidalgo, Paris Mayor & C40 chair
They pledged to put in place by 2020 their new, ambitious climate action plans, to be developed with help from the C40 Cities network.
The cities - spanning the globe from Accra to London to Rio de Janeiro - will also make clear to their residents the wider social, environmental and economic benefits of stepping up climate action.
In addition, C40, which supports cities in tackling climate change, will aid nine large African cities, including Cape Town, Addis Ababa, Lagos and Nairobi, to craft long-term green plans that align with the goals of the 2015 Paris deal to curb global warming, with backing from the German government.
"African cities are playing a leading and decisive role in delivering on the ambition of the Paris Agreement,” Paris Mayor and C40 chair Anne Hidalgo said in a statement.
Separately, the almost 7,500 cities in the Global Covenant of Mayors for Climate and Energy said their commitments combined would equal the reduction of nearly 1.3 billion tonnes of carbon emissions per year by 2030 - the size of Japan or Brazil's emissions, said Christiana Figueres, vice chair of the alliance.
It also launched a new global standard for measuring and reporting emissions from cities and local governments, to be applied from 2018.
The aim is to give national governments "very stringent and robust information" so that as 2020 draws near - the time by which they need to have peaked emissions to keep climate change in check - they can "increase their ambition safely and with confidence because so much has actually been achieved by the cities already", said former UN climate chief Figueres.
Bonn, for example, has recently put in smart street lighting that only switches on when someone passes by, together with a system that detects when recycling bins for clothing and glass are full, so that they are emptied only when needed.
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Stepped-up action to cut planet-warming emissions would lead to a "much, much better" quality of life in cities, including cleaner air and less concrete, Figueres told a summit of local and regional leaders on the sidelines of UN climate talks in Bonn.
Figueres and a number of city officials stressed the need to find more finance for municipalities to build greener infrastructure and use more renewable energy.
Maroš Šefčovič, a European Commission vice-president dealing with energy issues, said the common emissions measuring standard could be "a good selling point for mayors" to attract private-sector investors by helping demonstrate the positive impact of low-carbon projects.
Mauricio Rodas Espinel, the mayor of Ecuador's capital, said Quito is working with other local governments on a plan to enlist G20 governments and international financial institutions to find funding for climate action in cities around the world.
It hopes to launch the effort at a French climate summit in December.
Money could be used, for example, to expand Quito's plan to turn its historic district into a clean public transport area, using electric buses and taxis, and copy it across Latin America.
In California, a US state with a range of green policies, a state goal says 50 percent of energy must come from renewable sources by 2030. But Governor Jerry Brown noted that California has 40 million people and 32 million vehicles, with the number of cars growing at a faster rate than the population.
He urged local authorities to think about changing building standards and waste management systems to cut carbon pollution, while encouraging citizens to switch to electric vehicles, use bicycles or walk.
Planning more compact cities could also help, Brown said.
In the US, even if the administration of President Donald Trump has spurned climate action in favor of promoting fossil fuels, cities still have some power to pursue low-carbon policies, thanks to the federal system of government, he said.
"We have a vital opportunity to take the next steps to deal with climate change," he told the local leaders' summit.
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