Countries should sue the world’s biggest oil, coal and gas, and cement companies for damages resulting from climate change—says well-known climate scientist James Hansen.

Hansen, a former NASA scientist who warned Congress about the dangers of climate change in 1988, says global warming of 2°C, or even 1.5°C, is dangerous, risking sea level rise of at least 10 feet in as little as 50 years. That would put major parts of coastal cities like New York underwater. He believes major impacts of climate change are happening faster than what is reported in even the latest science reports, including the U.S. government’s Climate Science Special Report released last Friday.

An enormous amount of money is urgently needed to dramatically slash emissions of carbon dioxide (CO2), take existing CO2 out of the atmosphere, and for countries to cope with the impacts of climate change, Hansen argues. And that money should come from the companies that profited most from burning fossil fuels, Hansen will tell world leaders Tuesday in Bonn, Germany, at the annual United Nations climate negotiations.

Known as COP 23, negotiators from 197 countries are meeting this week to finalize details around the Paris Climate Change Agreement, including a process to increase emission reductions. The current reductions promised by countries under the Paris Agreement are only a third of what is needed to stay below 2C, according to the United Nations Environment Program.

“I tried to get an opportunity to address the negotiators but did not succeed. I will give my talk at a press conference,” Hansen told National Geographic in advance of the meeting.

Targeting “Carbon Majors”?

The companies that could be sued are known as the “carbon majors,” Hansen says. These are the 100 companies who have been the source of more than 70 percent of the world’s greenhouse gas emissions since 1988. ExxonMobil, Shell, BP, and Chevron are listed as among the highest carbon-emitting, investor-owned companies.

“The judicial system is the only way to get the funds needed to deal with climate change,” Hansen says. “Legislation won’t work because that’s where lobbyists rule.”

This legal action is comparable to the successful tobacco industry lawsuits that resulted in billions of dollars in settlements, he adds.

Legal Precedents

In fact, climate lawsuits are already happening. Last year, a Filipino government body called the Commission on Human Rights of the Philippines accused 47 carbon majors of human rights violations because of their role in climate change. Three California coastal communities sued 31 fossil-fuel companies in July. Last month, four municipalities on Canada’s west coast asked Chevron, Exxon, Shell, and others to pay their share of the climate costs those communities are facing. There is now even a nascent movement called Climate Law in our Hands that helps communities go after these carbon-emitting companies.

Causes and Effects of Climate Change

Governments are also being sued. A Dutch citizens’ group won the first-ever climate lawsuit against a government in 2015. The courts agreed that the Netherlands government wasn’t doing enough to protect its citizens and made the unprecedented ruling that the country’s annual CO2 emission reduction target had to increase from 17 percent to 25 percent by 2020 compared to 1990 levels. For comparison, 2015 (most recent available) annual U.S. emissions are four percent higher than 1990.

Hansen is involved in a 2015 lawsuit against the U.S. federal government, brought by 21 kids under the age of 21, including his own granddaughter. The case argues that the government’s failure to curb CO2 emissions has violated the youngest generation’s constitutional rights to life, liberty, and property. A trial will be held February 5, 2018 in the U.S. District Court of Oregon. Another group of youth just filed a lawsuit against Governor Bill Walker of Alaska alleging that “the state is violating their constitutional rights by putting fossil-fuel production above the safety of their lives.”

Could Puerto Rico sue the carbon majors for the billions in damages caused by Hurricane Maria? Legal experts say this is a difficult question. “You need to establish a sufficiently direct relationship between an act or omission by the entity sued and a significant impact,” says Jorge Vinuales, Professor of Law and Environmental Policy at the University of Cambridge.

However, some cases along these lines are starting at the UN Human Rights Committee, says Vinuales, who said he couldn’t yet provide further details because they aren’t public. For low-lying, small island nations whose existence is threatened by rising seas, a better approach might be to bring an action against some major polluters before either the International Court of Justice or the International Tribunal on the Law of the Sea, Vinuales says. “I'm quite confident that such a suit could be formulated in terms that could work,” he says.

A group of citizens could also try to sue carbon majors using transnational tort litigation. However, this approach may have been made more difficult by the fact that the U.S. climate delegation made sure the Paris Agreement included a paragraph that reduces the risk of litigation.

Future Solutions?

It has long been recognized that large amounts of funding is needed to help poorer nations cope with impacts of climate change and ramp up cleaner energy. In 2009, the U.S. and other developed nations agreed to step up financial support for developing nations to $100 billion a year by 2020. In 2015, the most recent year available, this support was estimated to be between $17 and $20 billion, according to Oxfam International. For comparison, a recent report estimated that extreme weather—made worse by climate change—and the health impacts of burning fossil fuels cost the U.S. economy at least $240 billion a year the last ten years.

The World Meteorological Organization also announced that 2017 is very likely to be one of the top three warmest years on record, and likely the hottest year in the absence of the El Niño phenomenon.

As COP 23 in Bonn began this week, Malaysia and Vietnam were just beginning to assess the damage from last weekend’s powerful Typhoon Damrey that killed at least 60 people. Global warming is already at 1C and there is much worse extreme weather to come unless carbon emissions are eliminated, says Hansen. To protect low-lying island nations and global shorelines, global warming needs to be less than 1C. That means removing at least 100 gigatons of CO2 from the atmosphere through afforestation and changes in land management, he says. That alone will cost at least a trillion dollars.

Lawsuits against governments and carbon majors could force what Hansen and many climate activists have long advocated: a carbon fee or tariff system on fossil fuels to raise their cost and provide funding. “As long as we allow fossil fuels to be cheap energy, and not required to pay their costs to society, we cannot kick our fossil fuel addiction,” he says.