Joe Miller, a tea party darling making his second bid for U.S. Senate, is trying once again to carve out the far-right territory as a climate change denier, though without directly saying so.
Meanwhile, after Miller raised global warming as a campaign issue in recent weeks, both leading candidates in the race for Republican primary votes downplayed the role played by human activity in its cause.
Miller, in a prepared statement Tuesday to reporters, called on Dan Sullivan, a former natural resources commissioner, and Lt. Gov. Mead Treadwell "to come clean with voters on their history of support for the man-made 'global warming' agenda."
Last week, Miller blasted Sen. Mark Begich, the Democrat the Republicans are hoping for a chance to unseat, for what he called "climate change deception."
Both Sullivan, as former assistant secretary of state in the Bush administration, and Treadwell, as former chairman of the Arctic Research Commission, have spoken out publicly on the need to act on climate change.
"Clearly, both of my primary opponents have joined with climate change alarmists to push for top-down federal regulation," Miller said in a written statement.
Miller wasn't available for an interview, an aide said, and he didn't respond to emailed questions about his own views on climate change. In his 2010 run for Senate, when he won the GOP primary but lost the general election to Sen. Lisa Murkowski's write-in campaign, Miller said the scientific support for climate change was "dubious at best."
In his statement Tuesday, Miller pointed to a 2012 study by scientists with the Alaska Climate Research Center, part of the University of Alaska Fairbanks' Geophysical Institute, that found temperatures in Alaska showed a cooling trend from 2000 to 2010.
He didn't mention that the researchers concluded that the trend showed a temporary variation, not a contradiction to the idea that Alaska is warming.
Most scientists say it is indisputable that human activity over the last two centuries has pumped enough carbon dioxide and other greenhouse gases into the atmosphere that climate change was inevitable.
Sullivan: No consensus
Miller said that while Sullivan was at the State Department he repeatedly addressed the "so-called 'climate change' problem" in speeches and interviews.
"In them, he unequivocally accepted the premise that climate change is man-caused and embraced numerous mitigation strategies" including reductions in consumption of fossil fuels, Miller said.
At a December 2007 fuels conference in Washington, D.C., for instance, Sullivan highlighted "our shared concern over the global environment and climate change" as part of the Bush administration's energy agenda.
In an October 2008 speech to the Scandinavian Renewable Energy Forum, Sullivan said "our energy challenges and climate change challenges stem primarily from a common source -- an overreliance on hydrocarbons as the world's primary form of energy."
At a 2007 press roundtable in Berlin, Sullivan talked about a Bush administration climate initiative that aimed to work with other major economies on "a long-term global greenhouse gas reduction goal."
Asked about Miller's criticism this week, Sullivan used one of Miller's buzzwords: "alarmists."
"Alaska is on the front lines when it comes to changes in our climate, and with seven billion people on earth, humans will have an effect," Sullivan said in an email. "However, despite what many climate change alarmists want us to believe, there is no general consensus on pinpointing the sole cause of global temperature trends."
Treadwell: Go for science
Miller also criticized Treadwell, who spoke about human-caused climate change and the need to act during his stint in the 2000s as chairman of the Arctic Research Commission.
For instance, Treadwell testified to a U.S. Senate subcommittee in 2008 that "we understand it is this nation's goal -- expressed with other nations -- to reverse the trend of climate change caused by humans. In the Arctic, research to support adaptation to and mitigation of climate change is high on our agenda. But as more forces than climate are working to produce an accessible Arctic, it is essential that our nation act now."
Miller quoted different testimony, before the House Committee on Foreign Affairs in 2009, in which Treadwell referenced emissions from natural sources as well as solutions such as "carbon sequestration," the process of capturing carbon dioxide from combustion and other sources and storing it underground.
Asked about climate change this week, Treadwell retreated from his prior strong statements about the human impact.
"Since where most of us live in Alaska was once covered by ice, I'm pretty sure humans didn't cause it all," Treadwell wrote in an emailed response. "Whether or not we caused some of it is a discussion that has taken years, and will take more. In the meantime, Alaskans are working to adapt."
In an interview, Treadwell said he has always supported better technologies, including cleaner fossil fuels. The science isn't clear on causes of climate change, and better research is needed, he said. He hasn't changed course just because he's in a hot GOP primary race, he said.
"I've promoted science on all the theories," Treadwell said. "Some scientists will say that you've gone past the tipping point, you stupid humans, you've warmed the Earth so much. ... There are people who just want to totally blame humans, period, and ignore what nature is doing. And nature has its own variations. And they are huge."
Miller's "press release about my views is hot air," Treadwell said.
Begich: No to carbon tax
As to Begich, Miller brought up a 2010 letter to Senate Majority Leader Harry Reid signed by Begich and 11 other senators that called for action, including "making polluters pay through a price on greenhouse gas emissions." The billionaire industrialist Koch brothers have accused Begich of supporting a carbon tax because of that.
But political ad watchdog groups have called the claim false, and Begich has said the mechanism for fees was unspecified and that he doesn't support a carbon tax. Miller accused him of changing his position.
None of the candidates said they support a carbon tax, a tool for curbing greenhouse emissions through fees on coal, oil and natural gas.
Miller also said that Begich was "calling for an end to scientific debate and for immediate action."
That mischaracterizes Begich's reaction to the newest U.S. National Climate Assessment, which said the impacts of change are being felt more in Alaska than any other state.
Instability of the Arctic ice pack and the impact of ocean acidification on fisheries are problems that need more scientific study, Begich said in a written statement May 6.
"At the end of the day, we need action based on facts -- not more debate," Begich said. "Alaskans want better research to ensure that we find effective solutions."
Reach Lisa Demer at ldemer@adn.com or 257-4390.