A group of youths from across the U.S. filed a lawsuit Wednesday challenging the federal government on climate change, claiming that the nation’s fossil fuel policies violate their constitutional rights.

The 21 plaintiffs, ages 8 to 19, argue in court documents that in continuing to promote the use of energy sources with a large carbon footprint, politicians in Washington are bartering America’s future for short-term economic gain.

“The current practices and policies of our federal government include sustained exploitation and consumption of fossil fuels. We brought this case because the government needs to immediately and aggressively reduce carbon emissions and stop promoting fossil fuels, which force our nation’s climate system toward irreversible impacts,” said 18-year-old Kelsey Juliana, a plaintiff in the suit.

“If the government continues to delay urgent annual emissions reductions, my generation’s well-being will be inexcusably put at risk,” she added. The lawsuit comes just weeks after Barack Obama’s administration unveiled plans for steeper cuts than expected in greenhouse gas emissions from U.S. power plants.

Trumpeting the mandatory 30 percent cut in carbon dioxide emissions by 2030, compared with 2005 levels, Obama described the move as “the biggest, most important step we’ve even taken to combat climate change.”

But others have called on the president to do more, suggesting that the cuts envisioned are insufficient to protect future generations from the impact of global warming.

The federal suit, filed in the U.S. District Court for the District of Oregon, asks the court to order federal agencies to develop a national plan to decrease atmospheric concentrations of carbon dioxide to a safe level of 350 parts per million by the year 2100.

Former NASA chief climate scientist James E. Hansen, a co-plaintiff, said meeting that target is necessary to avert catastrophe. He added that sensible means exist to rapidly phase down CO2 emissions, such as a “rising carbon fee” collected from fossil fuel companies, with funds distributed to the public.

“Instead, our president proposes ineffectual actions, demonstrably short of what is needed, and persists in approving fossil fuel projects that will slam shut the narrowing window of opportunity to ensure a hospitable climate system. I aim to testify on behalf of young people. Their future hangs in the balance,” he said.

The case relies on the public trust doctrine, which obliges the government to protect resources essential to the survival of all generations.

“Despite the government’s extensive knowledge of the dangers of CO2 emissions … defendants continued to authorize and promote fossil fuel extraction, production, consumption and all their associated emissions — to the grave detriment of future generations,” said Philip Gregory of Cotchett, Pitre & McCarthy of Burlingame, California, counsel to the plaintiffs.

Although many cases have applied the public trust doctrine to bodies of water, courts have yet to apply it to matters of climate change.

In 2014 a similar lawsuit involving some of the plaintiffs in Wednesday’s action was dismissed by the D.C. Court of Appeals, which affirmed a lower court’s ruling that the atmosphere could not be considered a federal public trust.

That's th fugure that Environmentalist Bill McKibben wrote every person needs to know." And it's a number discovered by Hansen and a team of scientists in 2013.

These youth, as well as future generations, have constitutional due process and equal protection rights to be free from governmental harm to those resources,” said Julia Olson, Executive Director and Chief Legal Counsel for Our Children’s Trust, and lead counsel on the litigation.