The global green movement is preparing for the fight of its life against efforts by Donald Trump to rollback action on climate change, with a surge in fundraising, planned court challenges and a succession of protests.

Environmental activists said the election of a climate change denier as US president, along with the prospect of former vice-presidential nominee Sarah Palin and various oil billionaires holding senior posts, has prompted an “outpouring” of donations.

This week, comedian, John Oliver, used his show to urge viewers to give to the Natural Resources Defense Council, while EarthJustice, a specialist in environmental law, reported a “substantial increase” in donations to wage the expected legal battles ahead. The Sierra Club said it has had 9,000 new monthly donors since election day, more than they had in the year to date.

After spending eight years cheering and occasionally scolding Barack Obama, environmentalists are now moving on to a war footing. Campaigns will be pitched around climate action and protecting national parks, with green groups claiming that public support for these things means that Trump has no mandate to tear them apart.

With Congress and the White House in Republican hands, the message will have to resonate in conservative ears rather than just energise the base.

“We won’t be in a defensive crouch for the next four years, licking our wounds,” said Michael Brune, executive director of the Sierra Club, America’s largest green group. “If Trump tries to go backwards on climate change he’ll run headlong into an organised mass of people who will fight him in the courts, in Congress and on the streets.”

May Boeve, the director of international climate group 350.org, which during the Obama presidency fought and won against the Keystone oil pipeline that is now back on the agenda, said building alliances with Trump’s heartland would be key.

“The best way to unite a progressive coalition with working class voters is to push for a 100% renewable energy economy that works for all,” she said. “Clean energy remains the greatest potential job creator in the 21st century, while climate change is still our greatest threat.”

The group said it was “preparing for the fight of our lives”, planning a mass mobilisation of people in Washington DC to put pressure on Trump, and a separate effort to push Obama to use his final days in office to pursue green measures, such as stopping the controversial Dakota Access pipeline.

Environmentalists said that, while Trump’s hand in the courts and Congress might be stronger than it was when they fought against George W Bush, one key difference was that businesses were now convinced of the need for curbing emissions. At the UN climate talks this week in Marrakech, a coalition of businesses including Kellogg’s and Mars, urged leaders to commit to long-term carbon plans.

“Ten years ago, US business wasn’t on board about tackling climate change,” said Craig Bennett, CEO of Friends of the Earth in the UK. “This time round you have a situation where US businesses and businesses more globally [support action], so this time around the environmental movement does not feel like it is on its own. We’re much better placed to fight this.”

In the UK, a cross-party group of MPs and environment groups has already begun meeting to discuss how to respond to anti-environmental rhetoric from the Trump administration, and how to deal with the consequences of the president elect delivering on his promise to withdraw from the Paris climate agreement.

Campaign group 10:10 cover London’s Parliament Square with pin wheels to highlighting public support for clean energy. Photograph: Andrew Aitchison/In Pictures/Getty Images

Climate campaigners are planning a protest outside the US embassy in London on Friday night at the prospect of the country pulling out of the Paris accord. “I am absolutely sure this will be one of many. There is another in a week. There will certainly be demonstrations on his inauguration day,” said Phil Thornhill, who is organising the protest that he hopes will attract a few hundred people.

On inauguration day, activists in Britain are also planning to drop “Build bridges, not walls” banners from all of London’s bridges – and potentially famous bridges elsewhere – to call on Trump to rethink any regressive steps on climate change.

In Australia, the Trump victory is driving an intensified focus from environmentalists to put a stop to a proposed coalmine there, which would be the biggest in the already coal-rich nation, and one of the biggest in the world.

Indian company Adani has been trying for years now to get approval to develop a $16bn (£13bn) coal mine in outback Queensland, as well as an expanded port on the country’s Great Barrier Reef coast so the coal can be exported.

Stopping the mine has already been a major focus of the climate movement in Australia, with several court cases challenging its environmental approvals, including on the grounds that the emissions its coal will produce will contribute to climate change.

But after millions of working class voters in the US were convinced to vote for Trump – their concerns not adequately addressed by the Democrats or the climate movement – green groups in Australia are concerned there may be a risk of something similar happening there. And that could end up giving strengthened political support to the controversial mine.

GetUp is a campaigning group in Australia, which raises money through crowdfunding and says it fights for human rights, economic justice and environmental sustainability.

Paul Oosting, national director of GetUp, told the Guardian he’s concerned the hard right in Australia were adopting similar tactics to those adopted by Trump.

But he said they have plans to undermine that.

“At the last federal election, GetUp targeted the hard right of Australian politics, because they hold Australia back on issues like global warming, and public health and education,” Oosting said.

That strategy appeared to be effective. “What we found was that if you listen to people’s concerns, and highlight the threats to their interests posed by the hard right, people seize the chance to turf them out,” said Oosting.

Oosting would not reveal details of the strategy, but said they would use similar tactics they found successful during the federal election, and apply it against the Adani mine.

GetUp is not alone. There is a consensus growing among environmental groups in Australia that Adani should be a primary focus of the climate movement there.

Activists in Australia dress as bleached, dead coral to call for greater protection of the Great Barrier Reef. Photograph: Justin Hawk/Greenpeace/AAP Image

Geoff Cousins, president of the Australian Conservation Foundation, said his organisation, which is currently fighting the mine’s approval in the country’s highest court, is going to redouble its efforts to stop the mine.

“We’ve commenced discussions with possible financiers [of the mine] – we met with banks and we will redouble those efforts. And we’re looking at a whole range of inventive measures that I’m not at liberty to discuss at the moment,” he said.