Three coastal communities in California have launched legal claims against some of the world’s biggest oil, gas, and coal companies. They are seeking compensation from the “carbon majors” to cover the predicted billions of dollars’ worth of damage and potential loss of life that rising sea levels are expected to cause.

The two counties of San Mateo and Marin County, as well as the city of Imperial Beach, are suing 37 fossil fuel companies, alleging that they knew about the dangers that climate change would bring about for almost half a century and yet actively worked in a “coordinated, multi-front effort to conceal and deny their knowledge of these threats.”

Included in the carbon majors are companies such as Exxon, Shell, and Chevron. It was revealed a few years ago that there are documents that show Exxon knew about climate change and the impact that burning fossil fuels has on it over four decades ago. Despite this, the company actively sought to confuse the science surrounding climate change, denying its validity and even funding anti-climate change groups. Unfortunately, Exxon were not alone in this tactic.

The coastal communities are claiming that the greenhouse gas emissions produced by these companies between the years 1965 and 2015 have locked in a sea level rise of 5.3 meters (17.4 feet) globally. They argue that this will have a major impact on their counties and cities, with flooding over the next 15 years predicting to affect thousands of residents and cost an upward of $15.5 billion (£11.9 billion) in Marin County alone.

“This is an unprecedented moment for climate change litigation,” says Sophie Marjanac, from the environmental legal group Client Earth, in a statement. “Multiple cases are being brought against Carbon Majors and governments worldwide."

Marjanac added: "Climate change has real impacts that put people, communities and their homes at risk. Lawyers are finding new and fresh ways to address these harms that have the potential to force Carbon Majors to pay for the damage their products have contributed to.”

The fossil fuel giants have faced legal battles before over their climate change impact, and so far have won them all. They argue that the cost of climate change and the measures needed to be done to protect against it are not a judicial issue, but a political one instead. They argue that action should be taken through changes in policy, not through battles in the courts.

This, however, is unlikely to stop many cases that are and most probably will be brought against them. Those from the coastal communities are fully aware of the hurdles that face them, but are equally aware of the exposure this case can bring to the fight against climate change.