Gov. John Hickenlooper on Tuesday signed an executive order committing Colorado to reduce greenhouse gas emissions in accordance with a global climate agreement rejected last month by President Donald Trump.

Hickenlooper said the state is joining the U.S. Climate Alliance, a coalition of 13 states and Puerto Rico agreeing to adhere to the goals set by the 2015 Paris climate accord.

“Coloradans value clean air and clean water,” Hickenlooper said at a news conference at Red Rocks in Morrison. “Our strong economy is a reflection of how our exhilarating outdoors attracts young entrepreneurs and the talent they need for their businesses. The vast majority of our residents, and indeed the country, expect us to help lead the way toward a clean and affordable energy future. In this process, we no doubt can address climate change while keeping a priority on household budgets.”

The executive order signed by Hickenlooper sets a goal of reducing statewide greenhouse gas emissions from 2012 levels by 26 percent by 2025 and by 35 percent by 2030. The governor said his order aims to harness market forces to accomplish emission goals rather than impose mandates.

Democrats and environmental groups hailed the announcement. But Senate Republicans lashed Hickenlooper for issuing what they termed a “unilateral executive order” and suggested the governor’s action could face a court challenge, while a trade group representing the state’s mining companies gave the plan a cold shoulder.

“Today, Colorado became the first state in the Rocky Mountain west to commit to meet the goals of the Paris Agreement,” U.S. Sen. Michael Bennet, a Democrat, said in a statement. “This is great news for our economy and environment. Our state is No. 1 in the country for wind energy jobs, and this announcement will only strengthen our leadership in building a clean energy economy and combatting climate change. As Coloradans do their part at home, I’ll continue to  fight for policies in Washington that leave a safer, healthier planet for future generations.”

Senate President Kevin Grantham, R-Cañon City, tore into Hickenlooper, saying the Democrat hadn’t consulted Republican lawmakers and questioning the governor’s authority to set the emission goals.

“This is not Washington, D.C.,” Grantham said in a statement, “and here in Colorado we do not govern by executive order.”

He contended that Colorado’s statutory goal of generating 30 percent of its power from renewable sources by 2030 can only be changed by new legislation.

“The governor’s failure to proceed in an open, collaborative, bipartisan way means this policy never will have the stamp of public legitimacy it needs, and that it most likely will be challenged in court,” Grantham said. “This unilateral action seems out of character for a governor whose overall successes stem from his willingness to take centrist positions, follow common sense, and work collaboratively with all parties.”

Stan Dempsey, president of the Colorado Mining Association, told Colorado Politics that the governor’s order would lead to fewer jobs in rural Colorado and could cost utility customers plenty.

“The governor talks about voluntary emission reductions, but the question is, what coal-fired power-generating stations are we talking about retrofitting or closing? He said there would be less coal use in Colorado. Frankly, it’s my understanding that the existing coal-fired power plants in Colorado have already been retrofitted, and any decommissioning of those existing plants is going to cost the ratepayers a lot of money.”

Dempsey said the announcement took him by surprise and criticized Hickenlooper for arriving at his decision without consulting power companies and the business community, much less representatives of the mining industry.

“Energy policy in Colorado should be developed through the legislative process, not through executive order,” Dempsey said. “We think local communities that might be affected by this decision deserve a more collaborative, open legislative process than the governor simply mandating emission-reduction targets.”

He added that he wasn’t impressed by elements of the governor’s order aimed at helping rural Colorado weather a transition to cleaner energy. Pointing to bipartisan 2010 legislation known as the Clean Air, Clean Jobs Act that mandated reducing emissions from older, coal-fired power plants, Dempsey said the law erased 1,000 jobs in the North Fork Valley, when coal production dropped. “We know what Clean Air, Clean Jobs did to rural colorado – it destroyed it,” he said.

Pete Maysmith, executive director of Conservation Colorado, said Hickenlooper’s move underlines Trump’s isolation from the world.

“The actions that the governor has announced will not only help us fight climate change, but will bring clean energy jobs and business innovation to the Centennial State,” Maysmith said in a statement. “With today’s announcement, President Trump has become even more isolated from the world, whose leaders are taking aggressive action to fight climate change.”

Jon Goldin-Dubois, president of Western Resource Advocates, said Colorado continues to demonstrate that the state can cut carbon emissions while enjoying one of the most vibrant economies in the country, fueled in part by thousands of new jobs in the clean-energy sector.

“Colorado has led in addressing climate change before with the state’s Renewable Energy Standard, the Clean Air-Clean Jobs Act and state methane rules – and now we will continue to show that the Colorado way protects our health, our environment and our economy,” he said in a statement. “The governor’s leadership in reducing emissions in our state, joining with other states across the country through the Climate Alliance, demonstrates that we take climate impacts very seriously. Longer and hotter droughts, severe storms, flooding and increased wildfires are too harmful to stand by and do nothing.”

Senate Minority Leader Lucia Guzman, D-Denver, applauded Hickenlooper for “sending a strong message that Colorado would continue to be a nationwide leader in combating climate change and advancing in the new energy economy.”

“Colorado has a moral obligation to tackle climate change not only for the preservation and health of our planet, but for the health and safety of our families as well,” she said.

House Speaker Crisanta Duran, D-Denver, said the governor’s decision keeps Colorado among leaders responding to climate change.

“Renewable energy enjoys widespread popular support in Colorado because not only is it good for our environment, it’s a key contributor to Colorado’s strong economy and best-in-the-nation unemployment rate,” she said in a statement.

House Majority Leader K.C. Becker, D-Boulder, praised Hickenlooper for taking the lead “after the failure of leadership we witnessed in Washington on this issue.”

“We’ve been trying for two years to set measurable goals for Colorado’s climate action plan, but each time we’ve run into a brick wall in the Republican-controlled Senate,” Becker said. “If the governor needs legislative support for this initiative, I’m eager to lend a hand.”

Hickenlooper reacted strongly when Trump pulled the United States out of the Paris accord in early June, calling it a “serious mistake” and worrying that Trump was ceding global leadership on a crucial issue.

“This is a historic global agreement between almost every nation on earth to address the single most pressing issue facing humanity,” Hickenlooper said at the time. “Abandoning this climate deal is like ripping off your parachute when you should be pulling the ripcord.”