With some national governments dragging their feet on emissions reductions, states and cities step in with new plans.

United Nations, New York City – In jarring contrast to the UN Climate Action Summit on Monday, where world leaders invested political capital – at least with lip service, if not concrete commitments – the first speakers during Tuesday’s UN general debate were two presidents who reject the international climate consensus.

Brazilian President Jair Bolsonaro and his US counterpart, Donald Trump, avowed ideological allies, have positioned themselves against global warnings about a looming environmental catastrophe.

Bolsonaro has staked his presidency on the exploitation of the country’s rich mineral wealth, despite devastating fires that scorched the Amazon region and endangered one of the world’s biggest carbon sinks.

Meanwhile, having announced his intention to withdraw from the Paris Agreement, Trump on Tuesday heralded the US position as the top fossil fuel producer on the planet.

As those two men reiterated their shared belief in national sovereignty – at all costs – and the right of countries to make full use of their economic resources, on the sidelines of the UN General Assembly (UNGA) a watershed event spotlighted the growing momentum of “subnational” movements championing ambitious climate strategies.

Branded as a “new form of collaborative leadership to build the zero-carbon economy”, the gathering in New York City showcased the “domestic coalitions comprised of cities, states, companies, and other actors working together to take bold climate action, build public support, and help their national governments”.

‘Action begets more action’

Alliances for Climate Action, which convened Tuesday’s meeting, calls itself “a global network of domestic multi-sector coalitions committed to supporting the delivery and enhancement of their countries’ climate goals”.

Part of the network is, We Are Still In, a US coalition with 3,500 representatives from all 50 states who have declared “Americans would not retreat from the global pact to reduce emissions and stem the causes of climate change”.

The declaration’s signatories represent 170 million Americans who constitute a gross domestic product of $6.2 trillion.

Among its partners are Climate Nexus, Ceres and World Wildlife Fund (WWF).

“As the name entails, [We Are Still In] communicates a strong commitment to staying in the Paris Agreement, and to American leadership,” said Mariana Panuncio-Feldman, the senior director of International Climate Cooperation at WWF.

“What you often don’t see are efforts to connect the constituencies [in different countries] with each other,” Panuncio-Feldman told Al Jazeera, saying that the Alliances for Climate Action brings together like-minded groups around a common goal.

“But ultimately, the story of the transition is a national story,” she said, adding that “it happens with the particularities” of each country.

“Ambition begets more ambition, and action begets more action,” she said, referring to the domestic alliances of subnational actors that have become increasingly important in the US and Brazil, as well as Japan, Mexico, Argentina and other nations.

Paulo Camara, the governor of the northeastern Brazilian state of Pernambuco, has been a trailblazer for the low-carbon economy – specifically with the deployment of large-scale solar farms.

“This is the growth story of the 21st century,” said Panuncio-Feldman, adding that the South American subnational actor is a positive model for collaboration, domestically and abroad.

Another member of the Alliances of Climate Action network is the Japan Climate Initiative, which has 400 signatories in metropolitan Tokyo, Kyoto and Yokohama – including companies, research institutions, non-governmental organisations and the faith community.

Mexico’s second-largest urban area, Guadalajara, has pursued ambitious climate action, and in Argentina, key figures from the agricultural sector are working on reducing emissions in food production.

But Panuncio-Feldman repeated that subnational progress cannot just occur “in lieu of national government action” to build infrastructure and pass energy regulation.

Not ‘circumventing the federal government’

Julie Cerqueira, executive director of the United States Climate Alliance, said her group also focuses on states but is not actively “circumventing the federal government”.

“We are reassuring the US population that we’re continuing to take climate action seriously in the US,” she told Al Jazeera.

The members make up just over half of the US population and around 40 percent of the country’s emissions. The alliance formed two years ago after Trump made public his decision on the Paris agreement.

Six governors – out of the 24 states and one territory in Cerqueira’s group – were at the UN this week. From California to Maine and Maryland, states have joined urban areas in legislating strict new climate targets.

Trump briefly attended the climate summit but was not invited to speak. On Tuesday, he did not explicitly mention the issue, but did say that “the future does not belong to globalists”, an indication of how he bristles at multilateral agreements, including on climate.

“Trump addressed the United Nations in a speech which failed to mention the climate emergency – a move totally disheartening and disingenuous to activists for an elected official sworn to protect our nation,” said a statement from The Climate Mobilization, a New York-based advocacy group.

“The US is the number-one producer of oil and natural gas anywhere in the world,” said Trump, adding that “we desire peace, cooperation, and mutual gain with all”. But Trump has justified opposition to international climate accords by saying drastic carbon emissions cuts reduce economic growth in the US and elsewhere.

Brazil’s President Jair Bolsonaro sits in a chair reserved for heads of state before his address to the 74th session of the United Nations General Assembly [Brendan McDermid/Reuters]

Brazil’s Bolsonaro meanwhile said his administration “has solidly committed itself to environmental preservation and sustainable development”. He praised Trump’s support for “freedom as nations” to make sovereign economic decisions about the extraction and consumption of natural resources.

He said that “Amazon forests are the lungs of the world” but denied that they are “being consumed by fire”.

Tijjani Muhammad-Bande, president of the UNGA, asked world leaders on Tuesday “not [to] condemn our children” and “deliver on our commitments made in Paris”.

Those words followed remarks by UN Secretary-General Antonio Guterres at the conclusion of Monday’s Climate Action Summit: “We have a long way to go. We are not yet there. We need more concrete plans, more ambitions.”

Guterres was giving tacit approval to subnational actors, who he hopes can push governments and carry along the torch of climate action.

“We have acknowledged the importance of regions, cities, and towns in making a difference,” said Mary Robinson, the former president of Ireland and UN High Commissioner for Human Rights.

“Business is also stepping up, with investments and philanthropy,” she told Al Jazeera. “There’s a lot of climate anxiety now. The best antidote is to be active about it.”