A climate change bill that would gradually reduce Colorado’s carbon emissions over the next 30 years is headed to the governor’s desk for approval — without a single Republican vote.

Even as the United Nations Intergovernmental Panel on Climate Change (IPCC) warns of irreversible and long-term impacts if emissions are not aggressively curbed, Republican lawmakers in Colorado’s Senate Wednesday questioned the scientific consensus, the impact of Colorado’s action on a global challenge and the economics of transitioning from fossil fuels.

“There is no consensus — no consensus whatsoever — on CO2 climate change or man-made climate change,” said Sen. Vicki Marble, a Republican from Fort Collins.

“It’s natural,” said Sen. John Cooke, a Republican from Greeley. “Pretty soon we’re gonna have global cooling. Because that’s what the Earth does.”

His comments echoed those of Sen. Ray Scott of Grand Junction, who recently argued that “climate change is occurring, but in the reverse order,” saying that “we have made massive improvements in our climate. Massive improvements.”

Other Republicans acknowledged climate change is happening, and that warming in Colorado exacerbates drought, beetle kill and wildfires. But they said they have concerns about the economic impacts of transitioning away from fossil fuels like coal — the state’s top source of electricity — and the $31 billion oil and gas industry.

“The effect that Colorado can have on greenhouse gases is so minuscule it’s not even worth talking about,” said Sen. Don Coram, a Republican from Montrose. “All the sudden you want to throw the baby out with the bathwater and get rid of the No. 1 industry in Colorado.”

In 2018, the oil and gas industry, including companies such as Noble Energy Inc., Anadarko Petroleum Corporation and Extraction Oil and Gas, spent $1.5 million on political committees that help elect Republicans to the state Senate and House, according to a Colorado Independent analysis of data from the Colorado secretary of state. Oil and gas businesses spent another $20,000 directly on candidates for office. That spending came on top of $40 million spent fighting a ballot measure to increase drilling setbacks.

House Bill 1261, which passed the Senate Wednesday on a party-line vote and the House in April, also along party lines, now goes to Gov. Jared Polis for his signature. Though he has not stated his position on the final bill, he is expected to sign it.

The bill sets the state on course to cut greenhouse gas emissions, which includes CO2 and methane, 50 percent by 2030 and 90 percent by 2050, both compared to 2005 levels. These emissions targets are still short of what some scientists say is needed to avoid long-term and irreversible impacts of climate change if implemented globally. Global CO2 emissions must be reduced to zero by 2050 or sooner to keep temperatures within 1.5 degrees Celsius, according to the IPCC.

In addition to its more moderate goals, the bill has no penalties should the state fail to meet the emission targets. Polis successfully fought against including any enforcement mechanism in the bill.

“We are supportive of goals, not mandates,” Polis said. “We believe we all have a joint responsibility to work together to help achieve those goals.”

Still, even the more moderate goals and lack of teeth failed to win over any Republicans.

“The underlying problem my side of the aisle has is they fear an economic dislocation and disruption,” Sen. Kevin Priola, a Republican from Henderson, said. “That was one of my underlying fears 10 years ago.”

Priola said he accepts the IPCC’s findings as fact and that he understands the science behind the heat-trapping effect of CO2 in the atmosphere having worked in a greenhouse when he was younger. He noted he also drives an electric car and has solar panels on the roof of his home. He said that he tells his Republican colleagues that the cost of solar is going down and could be a cost-effective alternative to fossil fuels, but they don’t buy it.

His colleagues who deny the scientific consensus around climate change should read more, he said.

Even so, on Wednesday, Priola joined his Republican colleagues in voting against the bill. His main issue, he said, was that the bill labeled greenhouse gases as “pollution.”

“Carbon is naturally occurring,” he argued. “If I drink 10 gallons of water, I will die. But I’m not dying from water pollution. I’m dying from the overconsumption of water. I just wanted to be more precise is the use of language.”

The opposition from Republicans comes as the mood among GOP lawmakers at the national level is starting to shift in support of climate change policies. The Democratic-controlled House this morning voted on a measure to block President Donald Trump from removing the U.S. from the Paris climate agreement. Party lines dominated with only three Republican lawmakers voting yes. Colorado’s three GOP congressmen — Ken Buck, Scott Tipton and Doug Lamborn — voted against the measure.

Here in Colorado, whether it’s denying the science or squabbling over semantics, the GOP’s opposition to climate change policy has left Democrats working alone on solutions.

“They don’t generally feel like there is a problem or a crisis,” Majority Leader Sen. Steve Fenberg, a Democrat from Boulder, said of his Republican colleagues. “The ones that do think that it’s not solvable.”

Some environmental groups praised the passage of the climate bill. But others said more aggressive targets are needed to have better odds of preventing long-term climate change impacts.

Democrats generally agree the targets should aim to zero out carbon emissions by mid-century, but say those reductions will require technology that does not yet exist to capture CO2 from the atmosphere and store it.

“They [Republican lawmakers] might be right that we can’t solve this problem,” said Fenberg. “But we sure as hell should try as hard as we can.”