From his claim that global warming was a gigantic hoax masterminded by China to his promise to pull the United States out of the landmark Paris agreement, Donald Trump’s surprise election win was widely decried by those who feared that recent progress in tackling climate change was about to come undone.

But a growing number of environmentally friendly American businesses – including major airlines and banks, as well as energy, tech and pharmaceutical companies – are pushing back against the president-elect’s attempts to dismiss climate change concerns and are planning to take the lead in the drive to make the US a worldwide leader at slowing or reversing the damage.

At the first Companies vs Climate Change conference in Fort Lauderdale on Wednesday, a succession of company executives, sustainable business experts and environmental activists spoke of the need for corporate America to step up efforts to help guide policy and fight what many see as the biggest threat facing the world today.

“If they don’t then the people who are hellbent on rescinding regulations and just allowing the market to function without any guardrails are likely to undo all the progress that the United States has made over the past 70 years,” said Richard Eidlin, vice-president of policy and campaigns for the lobbying group American Sustainable Business Council.

“Businesses that are in favour of addressing climate change, and maintaining environmental safeguards need to really express their views and express the business case for doing so. Not only is it good for them, and they’re generating profit and mitigating their risk, but what is just as important is stepping into the policy process.”

The summit was arranged before Donald Trump’s presidential election victory. Photograph: Ashley Cooper/Getty Images

The three-day summit, which brought together executives from companies including TD Bank, Citigroup, Nasdaq, Ingersoll Rand, Bright Power, United and Alaska Airlines, was arranged before Trump’s presidential election victory on 8 November. But because of that, the event became more poignant and provided companies a greater sense of urgency, according to Jason Youner, chief executive of solveclimatechange.com.

“Complaining about the election and the incoming administration doesn’t help anybody. We’re not here to debate whether there is climate change. We’re here to try to save the world, because the government’s not going to,” he said.

We’re here to try save the world, because the government’s not going to Jason Youner, chief executive of solveclimatechange.com

Joe Doolan, head of environmental affairs at TD Bank, said his company planned to press ahead with green initiatives that had won environmental awards and proved popular with customers, including a 15% reduction in its consumption of paper since 2010, partly through eliminating receipts and envelopes at ATMs.

“We set ourselves up as an environmental leader back in 2007 and became the first carbon-neutral bank in the US in 2010,” he said.

“We’ve installed solar canopies over our drive-through lanes, which has helped us offset our energy costs, and 90% of our waste is diverted from landfills. For us it’s about reduction, reduction, reduction.”

Jeffrey Perlman, founder and chief executive of New York-based Bright Power, an energy and water management company for mostly multi-family residential buildings, said he had “never been so happy for energy policies at a state level”.

He said: “We have an incoming administration not willing to even admit that climate change is a thing [but] they won’t be able to dismantle a lot of the great energy policies in the states that are being more progressive.

“If we’re talking about how people interact and consume energy, from how they heat and cool their homes to how they do business in a more environmentally friendly way, the only way that happens is through business.”

Smaller businesses say they also have concerns. Forest Green, a nature technology company in Virginia, has launched a “carbon transaction platform” that allows business and individuals to offset their carbon footprint using a mobile phone app.

“If compliance isn’t going to come from the government it really is going to be the power of individual decision-making that’s going to create the change,” said company representative Sarah McDonough.

The conference opened with a keynote address from David Fenton, a prominent climate change publicist, who said the politicisation of global warming had dissuaded many businesses from taking action.

“Business is more important than ever if we’re going to face a bunch of climate deniers,” he said. “The way climate change has become a partisan issue in the US has become a big issue in the world, other countries look at the US Senate, where one can’t get a simple, non-binding resolution passed that says humans are changing the planet, those countries say, ‘These yahoos in the US aren’t going to do anything, so why should we?’”

Eidlin believes that businesses need to send a loud enough message that the Trump administration cannot ignore them. “Many companies have expressed support for US staying in the Paris agreement, more are working with municipalities across the US, so there is a lot of activity,” he said.

“On the positive side, it’s great to see more companies stepping up. On the negative side, we need the policies put in place, which is why businesses, when they show up, really have an audience, because policymakers listen to what business people have to say.”