The four hottest years on record were 2015, 2016, 2017 and 2018, according to government institutions including NOAA and NASA.

The coalition plans to promote "a level playing field for all forms of energy production," embracing a holistic approach that includes natural gas, fossil fuels, nuclear energy and renewables. In that vein, the ACC is hoping to reclaim the mantle of President Theodore Roosevelt, the Republican president lionized for his conservationist bona fides .

As nations around the world bolster their efforts to address environmental degradation, the ACC announced the support of college Republican chairs from 10 more states, bringing to 30 the total number of state chairs voicing support for "a clean energy future," the ACC stated in a press release this week. Signatories include college Republicans from states such as Texas, Oklahoma, Michigan, Vermont, Kansas, Idaho and Utah.

The American Conservation Coalition — a 501(c)(4) nonprofit organization — is a right-leaning advocacy group that is partnering with young GOP campus activists to advocate market-friendly clean energy policies.

With the help of a right-leaning nonprofit, dozens of college Republicans are tackling what might appear to be a mission impossible enough for Tom Cruise: Persuading GOP elders to embrace environmentally friendly policy.

To be sure, the group has its work cut out for it in trying to sway opinions in a major party that is often viewed as skeptical about — if not outwardly hostile toward — environmental issues. In June, a Gallup poll showed only 18 percent support among Republicans for addressing climate change.

"Compared to how the Republican Party has been diminishing the issue for the last few years, we are encouraging them to make it a priority," Benjamin Backer, the ACC's 19-year-old president, told CNBC in an interview this week.

At least in principle, the Trump administration has advocated for striking a balance for energy development and conservation. In his "America First Energy Plan" blueprint, the president said the federal government would simultaneously embrace the shale revolution while pushing for energy solutions like clean coal.

"Our need for energy must go hand-in-hand with responsible stewardship of the environment," the plan states. "Protecting clean air and clean water, conserving our natural habitats, and preserving our natural reserves and resources will remain a high priority," the document read, adding that Trump would "refocus the EPA on its essential mission of protecting our air and water."

Backer told CNBC that "clean energy is an issue that brings both sides together and creates a lot of jobs if it's done the right way," said the sophomore at the University of Washington. "We need the national movement to make it a priority."

The effort comes at an auspicious time, with the United States remaining the lone holdout among countries that have signed on to the Paris climate accord.

Earlier this year, President Donald Trump announced the U.S. would cease participation in the agreement, and has vowed to renegotiate its terms — even as nearly 200 nations assembled in Europe on Saturday in a show of support for the 2015 deal.

According to the ACC's Backer, the Paris agreement has "a lot of flaws … and America can meet pro-environmental goals without being a part of it. The problem, however, is that America should be involved in the discussions and decision-making" in order to improve on its goals, he told CNBC.

The divergence of environmental views between millennial Republicans and their elders mirrors a dynamic reflected in a 2016 Pew Research opinion survey. The study cited the "polarized views" that characterize the debate over the environment, noting that the climate skepticism demonstrated by Trump runs deep among the GOP rank and file.

With the ACC's efforts, college Republicans intend to serve notice on the GOP's senior leadership, Backer insisted. "The Republican Party really values their young activists … and this will send a really strong message that things need to change," he told CNBC.

"We also want to send a really strong message to the RNC [Republican National Committee]. We want to say, 'Hey, guys, we really need this to be a message for 2020," Backer said. As polls show that millennials are widely disillusioned with both Democrats and the GOP, "Republicans will continue to lose the youth vote if they don't embrace the environment in a massive way," he added.

The RNC did not respond to CNBC's request for comment.

Correction: The ACC's full name is the American Conservation Coalition.