US mayors are seeking to go over President Trump’s head and negotiate directly at next month’s UN climate change conference in Santiago, they said as they met in Copenhagen for the C40 World Mayors Summit.



Los Angeles mayor Eric Garcetti, who rallied US mayors to commit to the Paris climate agreement after Trump announced his intention to withdraw the country in 2017, said he would ask the UN secretary general, António Guterres, on Thursday to give American cities a new role in UN climate talks.



“I’m going to bring it up with the UN secretary general,” Garcetti said. “If cities are invited to be at the table, I believe they will help accelerate the work that needs to be done. Hopefully, we can do it in concert with our national governments, but [we can do it] even where there is conflict.”



Garcetti, who was announced on Wednesday as the next chair of the C40 group of global cities, said he would use his position to seek “a more formal role in the deliberations” at the conference.



“The United Nations works directly with cities all the time ... so they shouldn’t feel feel scared about jumping down to that local level,” he said.

Antonio Guterres and President Donald Trump at a UN Security Council meeting in 2018. Photograph: Spencer Platt/Getty Images

Garcetti was in Copenhagen with 11 other mayors of US cities that as members of the C40 have committed to bring net emissions to zero by 2050.



According to the C40, carbon emissions are now declining in Boston, Chicago, Los Angeles, New Orleans, New York City, Philadelphia, Portland, San Francisco and Washington DC, as well as 21 non-US cities. A full 435 US mayors representing 71 million Americans have now signed up to Garcetti’s Climate Mayors organisation, committing them to adopt and uphold the Paris agreement.



“When [Trump] pulled out of Paris, the mayors jumped in,” Boston mayor Marty Walsh told the Guardian at the conference. “I think that Donald Trump’s inaction in the long run hopefully will be good for the climate, because it’s energised and activated more mayors to do more.”

Boston’s government on Thursday released an updated climate plan that included a demand that all new city buildings have a climate-neutral design, and that standards be brought in to decarbonise large buildings. LA last month approved a plan to build a giant 400MW solar project that will capture and store enough energy to power 283,330 homes.



Walsh, Garcetti and others were scathing in their assessment of the US president.



“I think that we have gotten so caught up in the noise around Donald Trump and his tweets,” Walsh said. “You can’t govern by Twitter, by attacking and insulting people, insulting women, insulting people, a college kid. You can’t govern like that.”

He said he believed Trump’s denial of the climate crisis was partly due to simple ignorance.

A firefighter monitors a wildfires in LA. “I always say, ask a firefighter if climate change is real in Los Angeles,” said Eric Garcetti. Photograph: Mark Ralston/AFP/Getty Images

“One, he’s denying it for his friends in certain industries, and number two, I think he’s denying it because he knows nothing about it,” he said.

Garcetti said Trump had been an obstacle to LA’s plans.

“We would love to have a president who was a partner instead of a polluter,” he said. “Literally in California, he’s forcing us to pollute ourselves and change our own rules that we’ve made for our own cities and own state, with car companies and ourselves. It’s crazy.”

As well as enacting ambitious city-level actions to reduce climate change, mayors are also suing the federal government to prevent it from interfering with their efforts.

“We’re suing to hold on to our clean-air protections, and to push forward with our fuel efficiency standards, our clean water,” Garcetti said.

At the same time, the federal government’s refusal to acknowledge the severity of the problem is starting to backfire, as extreme weather events have become too frequent for voters to ignore, and Republican-led state governments and the federal government are forced to act.

New Orleans mayor Latoya Cantrell at her inauguration in 2018. Photograph: Gerald Herbert/AP

﻿New Orleans mayor LaToya Cantrell pointed to the “fair share” deal she reached in May with Louisiana’s Republican governor, John Bel Edwards, to repair the city’s roads, canals and pipes, and improve stormwater management.

“We saw bipartisan support and a shift that we have never seen before at a state level,” she said. “And it is because of, one, the rate of rain that we’re seeing, and also the actions that are required to mitigate the city from flooding.”

Cantrell said she now hoped to see a similar shift at a federal level, after a recent surge in spending on emergency measures to counter extreme climate events.

New Orleans this summer suffered two so-called 100-year storms over just two months, she said, at one point receiving more than 20mm of rain in 90 minutes. The city is also, she said, losing “a football field every 100 minutes” to coastal erosion, while the Mississippi River has hit the highest levels recorded in 200 years.



“The amount of money that the federal government has had to put forward in a very limited time – just over a year – is extremely significant,” she said. “It’s more than the federal government has had to put out in decades. So, the dollar speaks.



“I think we will continue to see the federal government paying more attention, because you cannot deny the impact that it’s having on our cities.”

Floodwaters from Hurricane Katrina fill the streets near downtown New Orleans. This summer the city suffered two so-called 100-year storms over just two months. Photograph: David J. Phillip/AP

In LA, Garcetti said even members of Trump’s core voter base were beginning to become concerned about the climate.

“It’s a losing fight: whether it’s earthquakes in Oklahoma, flooding in Houston, the Florida Panhandle, this is affecting so-called red states as much as blue states,” he said.

“I always say, ask a firefighter if climate change is real in Los Angeles. Every single one of them – and they’re not, you know, a leftwing bunch – know it’s real because they’ve seen some of their colleagues threatened and even die on the line.”

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