In the decade since the historic Paris climate accord was signed, fossil fuel companies have been fighting hard to protect their business, pouring millions into lobbying and supporting climate-skeptic politicians — with success.

In the US, Donald Trump has again moved to pull out of the Paris Agreement and rolled back support for renewables in favor of oil and gas. Similar shifts are emerging elsewhere, as climate skeptic and denialist parties gain traction in Europe.

Across the corporate world, enthusiasm for environmental, social and governance (ESG) frameworks has also cooled amid political pushbacks and shifting market priorities. And at international climate conferences, the scale of lobbying by big oil and gas companies has been striking.

"At both COP28 and COP29, fossil fuel lobbyists showed up in the thousands, dwarfing many delegations, in particular those from the countries most vulnerable to climate change," said Erika Lennon, senior attorney at the Center for International Environmental Law in Washington. It's no different at this year's UN climate conference, COP30, in Brazil. 

Together, these lobbying efforts have weakened climate policy, says Richard Blanchard, director of the Centre for Renewable Energy Systems Technology at the UK's Loughborough University.

Keeping global temperatures down

Under the Paris Agreement, countries pledged to slow global warming to maximum of 2 degrees Celsius (35.6 degrees Fahrenheit) above pre-industrial levels, and ideally no more the 1.5 degrees Celsius.

Now, the UN says that goal of 1.5 degrees is dead, and current pledges put the world on course for at least 2.6 degrees Celsius of warming by century's end. As more fossil fuels are burned, the world continues to see record-breaking heat and weather extremes.

While a recent study found climate change would be much worse without the Paris Agreement, the transition to a world powered by clean energy is happening too slowly.

"People are confused," says Blanchard. Importantly, "the amount of oil being drilled has not reduced since 2015."

But for some experts, the ferocity of this determination to keep extracting and using polluting energy sources is not a sign of the Paris Agreement's failure, but of its reach. The louder the resistance, the more it signals that the fossil fuel sector, reliant on burning oil and gas to maintain its business model, feels threatened.

"The Paris Agreement would severely curtail their profits," says Blanchard. Their lobbying efforts, he adds, are "evidence of their defensive position."

What is working in the Paris Agreement

That defensive position reflects a shifting energy landscape. Global investment in clean energy has outpaced fossil fuels every year since 2016. According to the International Energy Agency (IEA), clean energy investment will hit $2.2 trillion in 2025 (€1.9 trillion) — double the $1.1 trillion expected for oil, gas and coal combined.

Renewables are also expanding at record speed, led by solar and followed by wind. Another IEA report projects clean energy capacity will grow faster through 2030 than it did over the previous five years in more than 80% of countries. China is driving much of that momentum through massive investment in solar and battery technology.

Some oil and gas giants are investing in green energy, but commitments vary. Exxon has backed carbon capture and hydrogen while still boosting oil and gas output, says Blanchard. BP, meanwhile, has scaled back renewable projects in favor of more drilling.

Fossil fuels still supply 80% of global primary energy. Even under optimistic clean-energy scenarios, oil and gas remain necessary through the 2030s and 2040s, as renewable generation, storage and grid capacity catch up.

For now, many producers are extracting as much as possible before stricter climate policies take hold, or before renewables become so cheap and reliable that fossil fuels are no longer as attractive.

Fossil fuel companies are anxious, says Blanchard. Market changes or regulations could make their hydrocarbon resources or infrastructure obsolete, leaving them with "stranded assets" and nothing more to show for their big investments.

Paris Agreement sent a signal to the world

According to the Paris Agreement, countries are free to set their own emission targets. The treaty's only enforcement tools are transparency and peer pressure — a "naming and shaming" system that many see as a major weakness.

But its real power lies not in setting emissions targets, but in enabling industrial transformation, argues Navroz Dubash, professor at Princeton University's School of Public and International Affairs.

"It is ultimately about emissions," he says, "but because emissions are the endpoint, it doesn't mean it has to be the starting point."

Countries want to grow their economies, and that requires more energy and more emissions like carbon dioxide, he points out. Supplying this energy with as little carbon dioxide as possible should be the goal. 

 "If you think of it from that way, the problem of addressing climate change is a problem of industrial transformation," says Dubash. 

The accord has encouraged some businesses to place bets on technologies that they may not otherwise have tried out.

"The really good news part of the story is the fact that, I think, this renewable energy transition is now inevitable," adds Dubash. "The Paris Agreement was part of sending that signal of inevitability."

International courts leaving their mark

Critics have long argued the Paris Agreement would struggle to drive a green energy transition because it offers only a framework and temperature goal, leaving emission cuts to each country.

However, the tide is turning, and "the momentum is not with the fossil fuel industry," says Erika Lennon. If oil, gas and coal companies don't diversify, then others will step into the void. 

Governments also have an obligation to regulate companies, including fossil fuel majors, and to ensure they are not harming people or the environment, says Lennon, pointing to recent ground-breaking opinions handed down by three different international courts, among them the International Court of Justice.

Such rulings have "put the fossil fuel companies on notice," adds Lennon. "So, it's not about fossil fuel companies embracing the Paris Agreement, but states fully complying with their obligations and regulating polluting industries."

Edited by: Jennifer Collins

Additional reporting by Katharina Schantz