A Delta plane lands as a U.S. Airways plane waits to take off at San Francisco airport. (Reuters/Lucy Nicholson)

Two California coastal counties and one beach-side city touched off a possible new legal front in the climate change battle this week, suing dozens of major oil, coal, and other fossil fuel companies for the damages they say they will incur due to rising seas.

The three cases, which target firms such as Chevron, ExxonMobil, BP and Royal Dutch Shell, assert that the fossil fuel producers are collectively responsible for about 20 percent of global carbon dioxide emissions between 1965 and 2015. They claim that industry “knew or should have known” decades ago about the threat of climate change, and want companies to pay the costs of communities forced to adapt to rising seas.

“We’re already living the impact of sea level rise,” said Marin County Supervisor Kate Sears. She said a county vulnerability study found hundreds of county businesses and other assets could be at risk in coming years.

“This lawsuit is a natural next step in how we address the expense we’ve already had in planning for and trying to remediate the impacts of sea level rise, but also in addressing the impacts we expect in the future.”

The suits represent a variation on several  largely unsuccessful attempts to hold individual companies responsible for their contribution to climate change.

In 2009, the vulnerable Alaskan coastal village of Kivalina used similar logic to sue a string of fossil fuel companies. The case failed when an appellate court ruled that federal action by the Environmental Protection Agency “displaces” their claim.

An even bigger setback came in 2011 when the Supreme Court decided against a public nuisance suit brought by eight states and New York City against a group of electric utilities — ruling, once again, that since EPA had begun to take action on climate change, the claim had been displaced.

The California cases are also proceeding under a legal doctrine called “public nuisance” (among other claims), which charges that under California common law, the companies have injured the counties and city by contributing to rising seas, and more frequent and severe flooding as a result.

But the difference is that this time, they are making state level nuisance claims rather than federal ones, which have already failed as courts pointed out that those worried about climate change had other recourses, such as EPA action.

The lawsuits were filed in California courts by Marin and San Mateo counties and the City of Imperial Beach, which sits south of San Diego near the Mexico border. Each cites specific damages expected from rising seas.

San Mateo cited worries about the flooding of the San Francisco Airport, along with up to $24 billion in assets being put at risk.

Marin County estimated nearly $16 billion of homes and businesses were threatened, and that with 6.7 feet of sea level rise, 7 percent of coastal roads would be “exposed to higher average sea level and storm threats at several locations.”

Imperial Beach cited the potential for “over $106 million” in property damages because of coastal erosion and argued the town has few resources to adapt to rising seas.

Vic Sher, a partner at the firm of Sher Edling who is helping lead the legal challenge, said the goal behind the lawsuits is to shift the “very real and very large costs of dealing with sea level rise” from ordinary citizens to the companies responsible for knowingly contributing to global warming.

He likened the cases to past litigation that sought to hold tobacco companies accountable for the public health toll of smoking, as well as efforts to force lead paint manufacturers to renovate homes where health risks remain.

“This is a very straightforward case for damages for wrongful conduct,” Sher said. “You have communities that are already injured, that have already spent a lot of money and are going to have to spent a lot more money in the future.”

Royal Dutch Shell declined to comment Wednesday, and ExxonMobil did not respond to a request for comment. The American Petroleum Institute, a trade group for oil and gas companies, also declined to comment on the pending litigation.

David Bookbinder, chief counsel with the Niskanen Center, a libertarian think tank, expects more such suits to be brought in different localities around the country.

“The California Supreme Court is going to view disappearance of its coastline quite differently than the Supreme Court might view it,” Bookbinder said.

A strength of the lawsuit, note some legal observers, lies in the fact that sea level rise is easily measurable, constant (unlike climate-affected weather events), and very strongly linked to a warming planet. Moreover, analyses have become more and more precise when it comes to mapping which locations will be inundated, or subjected to greater flooding risks, for a given level of rising seas.

Bookbinder said there could be a time when the science is powerful enough to try to assess blame for other climate related changes, such as droughts, but that sea level rise is a stronger and simpler case right now.

“What’s different about these lawsuits is the way in which they rely on the current state of climate science and the current state of information about what these companies knew, when they knew it and what they did with their knowledge,” added Michael Burger, executive director of the Sabin Center for Climate Change Law at Columbia University. “Over the last several years, a lot of information has come to light … What we know now is fundamentally different from what we knew years ago.”

But there are clear legal hurdles, too. The companies will surely point out that each individual corporation contributed only a small fraction to climate change, or resulting sea level rise. In addition, the companies themselves did not directly emit carbon into the atmosphere, but rather sold gasoline and other products that consumers  used to power their cars and homes.

“The litigants misunderstand nuisance law,” said Scott Segal, an attorney with Bracewell LLP who represents energy companies in D.C. “Commentators have suggested that nuisance law, a relative backwater in property law, is based upon conditions in which there are distinct producers and recipients of pollution. However, in the case of global climate change, a molecule of carbon is literally around the world in seven days. The requisite causation needed for nuisance suits is missing and unprovable.”

“It’s possible the suits will go nowhere, that they will be one offs that end in dismissal,” added Burger. After all, he said, there have been a number of previous lawsuits filed against the fossil fuel industry, raising public nuisance and other common law claims, and none have been entirely successful.

“But I think the potential here is that it becomes a first-of-its-kind set of lawsuits,” he said, agreeing with Bookbinder that other local governments are likely to pursue similar claims. “And you wind up with a groundswell of litigation that puts real pressure on the fossil fuel industry and on the government.”

Still, he added, “These are not easy cases to win. The plaintiffs will certainly have their work cut out for them convincing a judge, or perhaps a jury, that these particular companies bear enough of a burden of blame that they should be held responsible in a court of law.”