NEW YORK (BLOOMBERG) - More lawsuits seeking to curb carbon dioxide (CO2) emissions are likely in Europe, spurred by a recent report that makes the role of human activity "unequivocal" in global climate change.

Activists have seized on the Intergovernmental Panel on Climate Change's (IPCC) 3,949-page report, released last month, telling energy companies they will "see you in court".

"It may help to bring in a broader diversity of litigants," said Ms Catherine Higham, a policy analyst at the London School of Economics' Grantham Research Institute on Climate Change and the Environment.

"It might be the call to action for some groups that haven't necessarily been thinking about litigation in the past, but who are reading and starting to use litigation in ways they haven't done."

Environmentalists have tried for years to use the courts in their fight to slow the effects of climate change or to hold companies and governments accountable for the crisis, with limited success so far.

Most of the wins have taken place in Europe, including a ruling that requires Royal Dutch Shell to cut emissions more aggressively and a case that forced the German government to readjust its targets.

In the United States, the lawsuits have struggled to gain traction.

The international scientific consensus in the IPCC report could be used in a variety of geographically varied courts, especially when the claimants are not currently affected by climate impacts.

This could mean seeing more young people taking legal action around the world, a trend which has already been on the rise in places such as Germany.

"For young people who are arguing that they will be affected in the future, this report is useful for them," said Ms Louise Fournier, legal counsel at Greenpeace International. Ms Fournier expects more lawsuits to be launched by impacted people, including potentially by Greenpeace themselves.

IPCC publishes its reports every six to seven years. Earlier versions already were being featured in lawsuits, including a French case against the government for failing to have a credible route to climate objectives and a Peruvian farmer's claim against German energy company RWE.

Environmentalists used the data in successful lawsuits against the Netherlands, Colombia and South Africa, and in the Shell case.

This year's edition of the IPCC report, which focused on an updated assessment of the physical science basis of climate change, is even more definitive in blaming human activity than in the past, making it easier to argue the link between gas emissions and extreme weather.

It also provides "additional value" for claims of damages and compensation, said lawyer Roger Cox, who represented a Dutch environmental group in the case against Shell.

That may mean more litigation against Big Oil.

"We're going to see copycat cases happening in jurisdictions against corporations using similar arguments to the Shell case," said Mr Rupert Stuart-Smith, a founding member of Oxford University's Sustainable Law Programme's management team.

But the sobering conclusions of the report are not likely to trigger a flood of new lawsuits or bolster those already filed in the US, where several courts have already expressed reluctance to interfere in an international issue.

According to estimates from the Sabin Centre for Climate Change Law at Columbia University, there are about 1,400 climate-related cases in the US and 400 elsewhere in in the world.

Legal tactics in the US have included trying to sue fossil fuel companies for the costs of climate change or for allegedly misleading investors about the risks of global warming.

While the US Supreme Court did rule in 2007 that carbon dioxide can be regulated as a pollutant, few courts have been willing to impose liability for emissions.

"The IPCC report does nothing to change the primary problem for US climate litigants - the US legal system isn't set up to handle this type of claim," said Mr Brandon Barnes, a senior litigation analyst with Bloomberg Intelligence.

"A climate liability claim against a company or group of companies is always going to fail unless Congress changes the laws around liability. Until then, the courts are going to continue to punt the issue to the legislative branch."

Some US courts have said the problems associated with global warming need to be addressed through congressional legislation and international treaties, not lawsuits. And finding individual companies - even big oil companies - responsible for particular damage caused by climate change can be difficult.

'Found responsible'

"Somebody has to be found responsible for causing somebody else's harm from climate change, and courts have had a very hard time pinning that down," said Ms Jenny Rushlow, a director of the Environmental Law Centre at Vermont Law School.

In April, a New York court threw out a suit seeking to force five of the world's biggest oil companies to reimburse the city for the costs of climate change. Exxon Mobil also beat back a suit by New York attorney-general Letitia James, who claimed the company lied to investors about the financial risks posed by rising global temperatures.

But despite the setbacks, activists have continued to target energy companies and, increasingly, the banks that financed them, according to a report by the London School of Economics. A stronger consensus on the science of rising temperatures could provide a new tool for making claims and pushing for changes in policy.

Massachusetts has sued Exxon alleging it engaged in deceptive advertising about the role its products play in causing climate change, a claim the company rejects.

"This latest IPCC report reinforces the science-based allegations in our amended complaint against Exxon," a spokesman for Attorney-General Maura Healey said in an e-mail.

The industry is taking notice.

The Independent Petroleum Association of America, American Exploration and Production Council, and the American Petroleum Institute issued statements after the IPCC report acknowledging the need for reduced global emissions.

Chevron chief executive Mike Worth said the findings will require "mobilisation of huge amounts of capital" and "significant policy actions".