Those who believe the Earth's climate is changing as a result of human activity are comparable to those who once believed the planet was flat, according to Sen. Ted Cruz.

Senator Cruz (R) of Texas, who recently announced he plans to run for president in 2016, provoked a swift and snarky reaction online to his comments made in an interview with The Texas Tribune Tuesday, where he compared "global warming alarmists" to flat-Earthers, then implying that his position was comparable to that of Galileo Galilei during the same time period. (Point of clarification: Galileo's work did not delve into the planet's rotundity. But more on that later.)

"Today, the global warming alarmists are the equivalent of the flat-Earthers. It used to be [that] it is accepted scientific wisdom the Earth is flat, and this heretic named Galileo was branded a denier," Cruz said in the interview.

Cruz went on to say that "there has been no significant warming whatsoever for 17 years," referencing an often misunderstood theory of a recent "hiatus" in global warming.

"Now that's a real problem for the global warming alarmists. Because all those computer models on which this whole issue is based predicted significant warming, and yet the satellite data show it ain't happening," Cruz said.

Cruz then referred to a 1970s Newsweek article he had read, which discussed the theory that the planet was in a major cooling period at the time.

"Now, the data proved to be not backing up that theory," Cruz said. "So then all the advocates of global cooling suddenly shifted to global warming, and they advocated it's warming, and the solution interestingly enough was the exact same solution – government control of the energy sector and every aspect of our lives."

Numerous articles challenged both the logic of Cruz's comparison, as well as his interpretations of Galileo's scientific theories. Galileo was persecuted by the Roman Catholic Church for arguing that the Earth revolved around the sun. The idea that the Earth was flat had long-since been debunked, an inaccuracy pointed out in several articles, including an "open letter" from Galileo to Cruz published in The Washington Post.

But Cruz's comments are not without political significance, and they represent an interesting development in how Republican candidates could approach the climate change issue ahead of the 2016 election.

Cruz, who chairs the Senate's top science committee, has a history of being aggressive in his skepticism about human-driven climate change. He made headlines recently by pressing the head of NASA to prioritize space exploration over climate change research. His "flat Earth" comments conflict directly with comments made by President Obama last year who, in announcing new environmental regulations for coal-fired power plants, mocked climate change skeptics as the "flat-Earth society."

Perhaps the most interesting dynamic will be how Cruz's vocal skepticism jives with the positions of his Republican presidential challengers.

2015 is expected to be a big year for climate change policy, in the US and around the world. Months of negotiations are expected to conclude at the end of the year with a major international agreement in Paris on global warming pollution reductions. A draft of the agreement was prepared at a United Nations conference in Peru last December. Mr. Obama is also expected to make a decision on the Keystone XL pipeline this year.

And in 2016, Americans will go to the polls to elect a new president. Climate change has rarely featured as a main issue for American voters – in 2012, Obama and Republican candidate Mitt Romney never once mentioned climate change in their three debates – and that continues to be the case, despite the planet experiencing its warmest winter on record this year.

Recent polling data from Gallup revealed that Americans' levels of concern about a number of environmental issues, including global warming, are no higher today than a year ago. Some 55 percent of respondents reported some level of worry about the issue, though the the extent of that worry varied. Roughly one third – 32 percent – reported a "great deal" of worry, while one quarter – 23 percent – said they worried a "fair amount." That level of concern is lower than pollsters found in 2006 and 2009 and even lower than the highest level seen in 1999 and 2000, Gallup reported.

But polls also suggest that, while climate change isn't the most important issue for voters, American voters are increasingly concerned about it.

And prominent Republican leaders have been notably cautious in how they address questions about climate change. During the 2014 midterm elections, for example, prominent Republican candidates drew attention for answering climate-related questions with "I'm not a scientist."

Outside experts at the time interpreted the strategy as a way for GOP candidates to appease both the growing proportion of voters concerned about climate change, and major Republican donors from the oil and gas industry like Americans for Prosperity, a lobby group funded by billionaire conservative brothers Charles and David Koch.

Tim Phillips, president of Americans for Prosperity, told The New York Times during the 2014 midterms that his group intends to aggressively work during the 2016 presidential primary campaigns against Republicans who support a carbon tax or regulations.

“They would be at a severe disadvantage in the Republican nomination process,” Mr. Phillips told the Times. “We would absolutely make that a crucial issue.”

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Cruz's Galileo comments were in response to a question about whether he might be out of touch with younger voters, who do see climate change as a pressing issue. Whether climate change develops into a major 2016 election issue could be determined over the next few months, Cruz is already making his position clear. Other Republican candidates caught between the opinions of donors and voters may have to make similar commitments in the coming year.

If they decide to bring up "flat-Earth" as well, hopefully they leave Galileo out of it.