The 2016 Republican presidential primaries are already showing signs of turning into a competition to win the title of "candidate most dismissive of science." As a political strategy, this is as depressing as it is understandable.

There's little to gain and much to lose for the GOP White House hopeful who goes mainstream on science. Take global warming. Only 13 percent of Republicans in an AP-GfK poll in March said they were extremely or very confident that "the average temperature of the world is rising, mostly because of man-made heat-trapping greenhouse gases." That compares with nearly 55 percent of Democrats and, according to an analysis last year of studies to date, 97 percent of climate scientists.

Not to make any assumptions about political expedience, but there is — perhaps coincidentally — an exceedingly short list of possible Republican contenders who accept the scientific consensus that global warming is real and driven largely by human activity. Based on statements from the last few years, the only names on it are New Jersey Gov. Chris Christie and Ohio Gov. John Kasich. Another dozen or so run the gamut from serious skeptics to outright deniers.

Florida Sen. Marco Rubio's cavalier brushoff of climate change (and its associated droughts, floods, wildfires and rising seas) has drawn new attention to the anti-science GOP brand. "Our climate is always changing. And what they have chosen to do is take a handful of decades of research and say that this is now evidence of a longer-term trend that's directly and almost solely attributable to man-made activity, I do not agree with that," he said last weekend on ABC's "This Week."

The assertion earned Rubio a "false" rating from Politifact. Still, he repeated it Tuesday at the National Press Club and added that there's nothing we could do about it anyway. Banning all coal and carbon emissions in the United States will not reduce "these dramatic weather impacts that we're reading about," he said, because "the United States is a country; it is not a planet." In other words, deny science, blame China and fight tooth and nail against upcoming Obama administration regulations to cut carbon emissions at existing U.S. coal plants.

Rubio has held these muddled views for a while, but they are especially troubling now, given his home state (this month's National Climate Assessment named Miami as gravely at risk) and White House ambitions. His ideas on immigration, poverty and retirement issues show he can be thoughtful, and they bolster his statement on ABC that he is ready to be president. Yet a good president would not ignore scientific evidence or the potential for international diplomacy to reduce global warming.

The climate-change disconnect is just one aspect of a broad partisan science gap. The AP-GfK poll found Republicans are less confident than Democrats about several widely accepted scientific findings and theories, such as the age of the Earth (4.5 billion years) and the way it was formed (the Big Bang theory). Acceptance of evolution among Republicans, meanwhile, is in decline. While 54 percent in a 2009 Pew Research Center poll said they believed in evolution, only 43 percent said that last year. The AP-GfK poll similarly found 40.5 percent saying they were "not confident at all" that life on Earth "evolved" as a result of natural selection.

Republican presidential candidates have reflected many of these attitudes. At a 2007 debate, three of 10 aspirants for the nation's highest office raised their hands to signal that they did not believe in evolution. In 2011, moderate Jon Huntsman won some attention by tweeting: "To be clear. I believe in evolution and trust scientists on global warming. Call me crazy."

"If he's running for the Republican nomination, he IS crazy," commentator Patrick Buchanan responded on MSNBC.

The cycle of denial is once again in full bloom despite mounting piles of evidence, including new, separate studies from NASA and the University of Washington that conclude the massive West Antarctica ice sheet has started to melt. The sheet "holds enough water to raise global seas by several feet," the university said this week. Not to worry, the rising seas likely won't peak for another 200 to 500 years — but "more emissions would lead to more melting and faster collapse."

Sounds like a good reason to limit emissions or impose a carbon tax or negotiate an international agreement, but don't hold your breath waiting for proposals like that from the GOP presidential field. Republicans are obviously entitled to their opinions, as the late Sen. Daniel Patrick Moynihan and others have said. It's unfortunate for the rest of us that some of those opinions are blocking evidence-based congressional action. Science should be the foundation of national policy, not a starting point for debate.

Follow Jill Lawrence on Twitter @JillDLawrence. To find out more about Jill Lawrence and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.