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The mayors of the four cities announced their plans to combat air pollution by banning diesel vehicles at the C40 Mayors Summit, which is currently happening in Mexico City.
"Mayors have already stood up to say that the climate change is one of the greatest challenges we face," Paris Mayor Anne Hidalgo said in a statement. "Today, we also stand up to say we no longer tolerate air pollution and the health problems and deaths it causes - particularly for our most vulnerable citizens. Big problems like air pollution require bold action, and we call on car and bus manufacturers to join us."
Mayors and local leaders form 86 cities around the world - including Chicago Mayor Rahm Emanuel, Rio de Janeiro Mayor Eduardo Paes, and Shenzhen Deputy Mayor Ai Xuefeng - have convened at the C40 summit to discuss plans for addressing climate change.
Cities have increasingly been leading the charge on climate action, since more than half of the world's population lives in cities, a number that's expected to rise to 70% by 2050. That means cities also account for a large portion of greenhouse gas emissions, putting them in a powerful position to fight global warming.
At the summit, mayors discussed a new report that outlines actions cities can take that would account for 40% of the emissions reductions necessary to keep the global temperature from rising more than 1.5 degrees Celsius. To do that, the report found, they'll need to ensure that emissions peak by 2020, then drop dramatically after that.
Removing pollutive cars is one way to achieve that.
"Our goal is to ultimately remove all cars from the center of Athens in the years to come," the Mayor of Athens, Giorgos Kaminis, said in a statement.
Other cities have also initiated efforts to eliminate cars from their centers - Oslo plans to implement a car ban by 2019, and Copenhagen and Brussels already have Europe's two biggest car-free zones.
Those efforts, Mexico City Mayor Miguel Angel Mancera said, "ease congestion in our roadways and our lungs."