Climate science is finally winning in court and it could save endangered species. Last week, the San Francisco-based 9th Circuit Court of Appeals determined that federal authorities can use climate models to list a bearded seal subspecies as “threatened” under the Endangered Species Act. The ruling reinforced the principle that climate projections are valid science, and the government can use that science to warrant protection to species whose habitats are threatened by global warming.

Climate projections are valid science

All kinds of species, not just those that depend on ice and snow for survival, might be affected by the ruling, according to environmental lawyers. “The court recognized that you can’t just wait until a species is on the brink of extinction” before it’s listed as “threatened,” says Emily Jeffers, a staff attorney at the Center for Biological Diversity, which sought the listing of the bearded seal. “The whole point of the Endangered Species Act is to prevent that from even happening.”

The Endangered Species Act was passed by Congress in 1973 to boost the conservation of threatened and endangered animals and plants. When making a decision, the authorities look at a species’ habitat and range, and whether the species is threatened by disease, predators, or hunting. By law, they have to make their determination “solely on the basis of the best scientific and commercial data available.”

But the government had to fight to defend the best available data. In 2012, the National Marine Fisheries Service (NMFS) decided to protect a subspecies of the Pacific bearded seal because climate models showed its habitat could be devastated by 2095. But the state of Alaska, oil interests, and native groups challenged that decision, saying that the seals are currently plentiful and that the climate projections were too speculative. In 2014, a district court agreed, and the seals were left unprotected.

Last week, a three-judge panel of the San Francisco-based appeals court overturned that decision, arguing that sea ice loss would “almost certainly have a negative effect on the bearded seal’s survival.” Climate change projections, in other words, are sound science.

This is not the first time that climate models have been upheld in court for the listing of a species. In 2008, the US Department of the Interior listed the polar bear as “threatened” because the animal’s sea ice habitat was shrinking and projections showed it would continue shrinking in the future. In that case, the listing was also challenged in court and upheld. “As with the seals, the court agreed that the science was sound and the loss of ice and therefore population was foreseeable,” says Josh Galperin, the director of the Environmental Protection Clinic at Yale Law School. And in April of this year, a district court ruled that the Fish and Wildlife Service must take climate projections into account when listing the wolverine, a small animal that looks like a bear and needs snow for its survival.

Last week’s ruling validated that principle — and that’s important. “As more courts make the same decision, that’s influential in other circuits,” says Rebecca Riley, a senior attorney at the Natural Resources Defense Council. The ruling was also made by a high-level court, which means that if the plaintiffs want to appeal the ruling, they’d have to petition the Supreme Court to take the case. That’s very unlikely, according to environmental lawyers.

But a lawyer for the state of Alaska said they might try to appeal the ruling anyway, or ask the appeals court to reconsider the case. “If this opinion stands, the National Marine Fisheries Service would list a species that is abundant and in good health based on the claim that climate change will impact habitat over the next 100 years and may cause harm,” Brad Meyen, senior assistant attorney general for Alaska, wrote in an email to The Verge.

The same claim can be used to protect a big number of species, according to environmental groups. Apart from the wolverine, federal authorities could now decide to list other animals like the pika, a small, rodent-like mammal that lives up high in the mountains and needs the cold to survive. (The pika was denied listing by federal authorities in 2010.) Another candidate is the Pacific walrus, which relies on sea ice to survive. And the ruling could also influence the appeals court’s decision on another species that the NMFS listed as threatened: the ringed seal, another Arctic seal that’s threatened by climate change.

In other words, the ruling is a big environmental victory. “It’s good to know that we can protect a species when we think it’s on the path to being in real trouble,” says Jon Kurland, the assistant regional administrator for protected resources at NOAA Fisheries. “Hopefully we can do something about it rather than waiting until it’s actually endangered of extinction before we can act.”