CHEYENNE, Wyo. (AP) — A federal judge has dismissed a legal challenge from environmental groups that sought to block federal coal leases in Wyoming's Powder River Basin on the grounds that burning the coal would contribute to global warming.

The Sierra Club and WildEarth Guardians had challenged the federal government's sale of leases on 2 billion tons of coal. The leases are on U.S. Bureau of Land Management lands near Arch Coal's Black Thunder mine and Peabody Energy's North Antelope Rochelle mine — two of the world's largest coal mines.

U.S. District Judge Colleen Kollar-Kotelly of Washington, D.C., on Monday dismissed two merged lawsuits, saying the groups lacked standing to sue because they failed to show leasing the tracts would cause climate change that would specifically harm their membership. The groups had claimed global warming from burning the coal would damage their recreational, aesthetic and economic interests.

Kollar-Kotelly wrote there was evidence that even if the disputed tracts lay fallow, "domestic and international consumers' consumption behavior would not be materially affected and the national energy portfolio would remain unchanged."

Beverly Gorny, spokeswoman for the BLM in Cheyenne, said Thursday the leases were sold this year but haven't been mined yet. She said they're adjacent to current mining sites.

John Horning, executive director of WildEarth Guardians in Santa Fe, N.M., said his group is disappointed with Kollar-Kotelly's ruling and plans to appeal.

"We're especially disappointed given that this ruling never gets to the real merits. We've been bounced on standing," Horning said. "And it's, I think, a pretty cynical view of the impacts of climate change to dismiss one's standing because the impacts are so diffuse. We're all affected by climate change."

Horning said his group has focused on the Powder River Basin because of the scale of mining and coal production there. Wyoming is the nation's leading coal-producing state and most of its production comes from that area.

Marion Loomis, executive director of the Wyoming Mining Association, said Thursday he's thankful the judge dismissed the suits. His group is a member of the National Mining Association, which intervened as a defendant.

"The Department of Interior has to follow their rules and laws that are on the books," Loomis said. "I don't think there's anything on the department's laws, rules or regulations that says they have to take into account any climate change. Until that happens, they shouldn't be taking that into consideration in their environmental reviews."

Loomis said his group has no position on the issue of how coal mining may affect global warming.

"Obviously burning coal does release CO2," Loomis said. But he said the world is going to use coal and his organization hopes Wyoming will be one of its sources for affordable, reliable electricity.

Wyoming's coal industry generates about $1.2 billion in taxes, royalties and fees each year for Wyoming's state and local governments, Loomis said. And its $700 million payroll is a huge economic driver for the state, he said.

Gov. Matt Mead issued a statement Thursday calling the judge's decision good news for Wyoming and the thousands employed in its mining industry.

"It is also good news for the nation because 20 percent of Americans turn their lights on thanks to Wyoming coal," Mead said. "Coal is affordable and integral to our country's power supply, and I will continue to advocate for it."

But while coal production remains a cornerstone of Wyoming's economy, federal figures don't inspire much optimism. They show that the share of U.S. electricity that comes from coal is projected to dip below 40 percent this year, the lowest level since the government began collecting data in 1949. Four years ago, it was 50 percent, and by the end of this decade, it is likely to be near 30 percent.

The prospect of falling coal demand has prompted Wyoming's government to look for new markets.

Mead and other state officials traveled to China in June to tour clean coal facilities there. After returning, Mead said he believes Wyoming needs to explore how it could export coal to China to meet that nation's growing demand.

Meanwhile, opposition has been mounting in the Northwest to the prospect of establishing constant rail traffic from Wyoming mines to serve deep-water ports that would export coal to China.

Horning said he believes federal coal leases don't realize as much money for taxpayers as they should.

"Given that the federal coal leasing process subsidizes the cost of coal, and gives these companies a sweetheart deal, I think it's outrageous that U.S. coal is being exported to enrich a few companies, and benefit China, and worsen the climate crisis," he said.