(Yahoo News photo illustration/AP)

The effects of human-induced climate change that scientists have predicted in the past are now observable: powerful heat waves, lost sea ice and higher sea levels.

These same experts say worldwide temperatures will continue to increase over the next few decades as a result of greenhouse-gas production — with potentially catastrophic consequences.

Most leading scientific organizations have issued public statements saying climate-warming trends have been the result of human activity: the Intergovernmental Panel on Climate Change, the National Academy of Sciences, the American Association for the Advancement of Science and many others.

Studies in numerous peer-reviewed scientific journals show that 97 percent of active climate scientists endorse this position.

In an attempt to be objective, some journalists and pundits have at times given equal weight to arguments on both sides of the “debate” — creating the logical fallacy of false equivalence. Just because the public is divided over an issue does not mean the experts are.

Meanwhile, the 2016 presidential candidates’ positions on climate change fall across a wide spectrum. Some laugh off man-made climate change as a hoax, while others accept the scientific consensus, though they disagree on the best course of action.

This is where the contenders for the White House stand on the issue:

The Democrats

All of the Democratic candidates say that anthropogenic, or human-action driven, climate change is a reality, though their commitment to fighting it varies.

Hillary Clinton, former secretary of state

Anthropogenic climate change: real

Hillary Clinton is widely considered the Democratic frontrunner. (Photo: International Business Times)

Hillary Clinton has called climate change “the most consequential, urgent, sweeping collection of challenges we face as a nation and a world.”

“It’s hard to believe that there are people running for president who still refuse to accept the settled science of climate change, who would rather remind us they are not scientists than listen to those who are,” she said in a campaign video last month.

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Clinton says she would set two ambitious national goals on her first day as president: (1) having more than half a billion solar panels installed by the end of her first term and (2) generating enough power with renewable energy to power every home in the U.S. within 10 years.

But her actions have not always backed up her rhetoric.

As a senator, Clinton voted in favor of offshore oil drilling. As secretary of state, she supported hydraulic fracturing, or fracking, for shale gas domestically and abroad.

“Now, I know that in some places is controversial. But natural gas is the cleanest fossil fuel available for power generation today, and a number of countries in the Americas may have shale gas resources,” she said in a speech to the Inter-American Development Bank in April 2010.

The Clinton Foundation has accepted millions of dollars from multinational oil companies, such as ExxonMobil and ConocoPhillips. Clinton refuses to give her opinion on the controversial Keystone XL pipeline, which environmentalists say would increase carbon pollution dramatically.

On the other hand, she strongly supports the Environmental Protection Agency’s CO2-reducing Clean Power Plan, which was finalized this month, and said it must be “protected at all cost.”

“No matter what the deniers may say, sea levels are rising, icecaps are melting, storms, droughts and wildfires are wreaking havoc. Thirteen of the top 14 warmest years in recorded history have all occurred since 2000,” Clinton said at a League of Conservation Voters dinner in December 2014.

Her campaign is expected to present its “comprehensive energy and climate agenda” over the next few months.

Bernie Sanders, U.S. senator from Vermont

Anthropogenic climate change: real



For environmentalists, Bernie Sanders just might be the best candidate. For the “drill, baby, drill” crowd, he might be the worst.



Climate change and the environment are central issues to his campaign.

He says the U.S. must take a leading role in confronting climate change by moving our energy system away from fossil fuels and toward clean energy.

“Unless we take bold action to address climate change, our children, grandchildren and great-grandchildren are going to look back on this period in history and ask a very simple question: Where were they?” Sanders said on his website. “Why didn’t the United States of America, the most powerful nation on earth, lead the international community in cutting greenhouse gas emissions and preventing the devastating damage that the scientific community told us would surely come?”

Sanders led the opposition to the Keystone XL pipeline. He introduced (with Sen. Barbara Boxer) what some consider the gold standard of climate change legislation to tax carbon and methane emissions and secured $3.2 billion in the economic stimulus package for greenhouse gas emission-reduction grants, according to his website.

Bernie Sanders, left, and Martin O’Malley. (Photos: AP)



Martin O’Malley, former Maryland governor

Anthropogenic climate change: real

Martin O’Malley put forth his aggressive plan to combat climate change in an op-ed for USA Today.

In the opinion piece, O’Malley said President Obama’s “all of the above strategy” has made the country more energy independent, but that we cannot truly confront climate change while still building oil pipelines and drilling offshore.

“Instead, we must be intentional and committed to one over-arching goal as a people: a full, complete transition to renewable energy — and an end to our reliance on fossil fuels,” he wrote. “Saving the world is a goal worthy of a great people. It is also good business for the United States of America.”

He added that protecting the nation from the devastation of global warming and capitalizing on job opportunities in green energy would be central to his presidency.

“I believe, within 35 years, our country can, and should, be 100% powered by clean energy, supported by millions of new jobs,” he said. “To reach this goal we must accelerate that transition starting now.”

Lincoln Chafee, former Rhode Island governor

Anthropogenic climate change: real

Lincoln Chafee says protecting the environment can co-exist with economic strength.

In February 2014, Chafee signed an executive order creating the Rhode Island Executive Climate Change Council to advise the governor, general assembly and public on best practices to address the challenges brought on by climate change.

“I am establishing the council because for too long there has been strong evidence and scientific consensus that man-made greenhouse gases will have profound effects on global climate, weather patterns and ocean conditions — effects that the state cannot afford to ignore,” he said at the time.

Lincoln Chafee, left, and Jim Webb. (Photos: AP)

Jim Webb, former U.S. senator from Virginia

Anthropogenic climate change: real

Jim Webb acknowledges that humans are contributing to climate change, but his actions in the Senate have incited the wrath of environmentalists who feel he’s exacerbating the problem.

A Virginia populist, he regularly defended the coal industry and adamantly opposed the Clean Air Act’s rules to curb emissions from coal power plants.

“I am not convinced the Clean Air Act was ever intended to regulate or classify as a dangerous pollutant something as basic and ubiquitous in our atmosphere as carbon dioxide,” he said in March 2011.

Webb also supported an amendment proposed by West Virginia Sen. Jay Rockefeller to suspend the EPA’s regulation of greenhouse gases.

“This will result in a long and expensive regulatory process that could lead to overly stringent and very costly controls on carbon dioxide and other greenhouse gas emissions,” he said in a press release that same month.

The Republicans

Most, though not all, Republican presidential primary candidates are skeptical of anthropogenic climate change. A few even think it is a hoax concocted by liberals as an excuse to push for bigger government.

Donald Trump, real estate magnate/reality TV star

Anthropogenic climate change: hoax

Donald Trump participates in the first Republican presidential debate at the Quicken Loans Arena in Cleveland. (Photo: John Minchillo/AP)



Donald Trump has said global warming is a hoax created by the Chinese so that the United States would not be competitive in manufacturing, a contention scientists scoff at.

The billionaire reality TV star also has criticized the Obama administration for “the billions it pissed away” investing in failed green energy projects.

On numerous occasions, Trump has brought up the persistence of temperate zone seasons as an argument against the existence of climate change.

“It’s snowing & freezing in NYC. What the hell ever happened to global warming?” he tweeted in March 2013.

Ted Cruz, U.S. senator from Texas

Anthropogenic climate change: pseudoscience

Ted Cruz said global warming is not happening and dismissed it as a “pseudoscientific theory” in a conversation with Yahoo global news anchor Katie Couric.

“Satellite data shows there has been no significant recorded warming — none. When the satellites are measuring the temperature, it’s not happening,” he said.

Cruz claimed that politicians who want more control over people’s lives are pushing climate change.

Ted Cruz and Carly Fiorina. (Photos: AP)

Carly Fiorina, former CEO of Hewlett-Packard

Anthropogenic climate change: real

Carly Fiorina says the answer to the problem of climate change is not regulation, but innovation.

“There is a lot of consensus among the scientists that climate change is real and human activity contributes to it. There is also absolute consensus among the same scientists that a single nation acting alone can make no difference at all,” she said in February 2015 at an event co-hosted by the New England Council and New Hampshire Institute of Politics.

Fiorina said she resents when people use “half the science” to destroy the livelihoods of people living in coal mining or agricultural communities.

“We can shut down everything in this country and it will make no difference because the scientists are clear,” she said. “To really combat this, we need an effort that is global in scope over many decades, costing trillions of dollars.”

Jeb Bush, former Florida governor

Anthropogenic climate change: undecided

Jeb Bush acknowledges that the climate is changing but thinks it is “intellectually arrogant” to say it is anthropogenic.

“I don’t think the science is clear of what percentage is man-made and what percentage is natural. It’s convoluted,” he said at an event in New Hampshire in May, according to CNN.

The brother of former President George W. Bush does not count climate change among his “highest priorities.”

“For the people to say the science is decided on this is really arrogant, to be honest with you,” Bush continued. “It’s this intellectual arrogance that now you can’t have a conversation about it, even. The climate is changing. We need to adapt to that reality.”

Jeb Bush, left, and Scott Walker. (Photos: AP)

Scott Walker, Wisconsin governor

Anthropogenic climate change: opinion unknown — actions indicate it’s not a priority

When asked by a 7-year-old boy whether he cared about climate change, Walker sidestepped the question by talking about how when he was a Boy Scout he thought campsites should be clean.

Slate published an article arguing that Walker just might be the worst Republican candidate for the environment because of his long track record of “undermining pro-environment programs and policies while supporting the fossil fuel industry.”

Similarly, in Scientific American, science journalist Siri Carpenter said Walker has reduced the role of science in making environmental policy and silenced state workers from discussing climate change.

“And he has presided over a series of controversial rollbacks in environmental protection, including relaxing laws governing iron mining and building on wetlands, in both cases to help specific companies avoid regulatory roadblocks,” she wrote.

Ben Carson, retired neurosurgeon

Anthropogenic climate change: irrelevant

In a March 2014 op-ed for the Washington Times, Ben Carson said it makes little sense “to use climate change as an excuse not to develop our God-given resources.”



As human beings, he continued, we must take care of our surroundings and pass them on to future generations.

Later that year, in a November interview with Bloomberg News, he said that the issue of global warming is “irrelevant.”

“There’s always going to be either cooling or warming going on,” he said. “As far as I’m concerned, that’s irrelevant. What is relevant is that we have an obligation and a responsibility to protect our environment.”

Ben Carson, left, and Marco Rubio. (Photos: AP)

Marco Rubio, U.S. senator from Florida

Anthropogenic climate change: false or inconclusive

Marco Rubio has voted against congressional legislation that acknowledges climate change is happening or that human activity is a driving factor. That amendment, which was sponsored by Sanders, was ultimately rejected in March.

In February 2010, he told the Tampa Tribune that he does not think there is enough “scientific evidence to justify” a belief in the existence of man-made global warming.

When asked if he accepts the scientific evidence that the global climate is changing, Rubio replied, “The climate is always changing. The climate is never static. The question is whether it’s caused by man-made activity and whether it justifies economically destructive government regulation.”

John Kasich, Ohio governor

Anthropogenic climate change: position unclear

At a Republican fundraiser in Ohio in April 2012, John Kasich said he “believes” in climate change.

“This isn’t popular to always say, but I believe there is a problem with climates, climate change in the atmosphere,” Kasich said, according to the Columbus Dispatch. “I believe it. I don’t know how much there is, but I also know the good Lord wants us to be good stewards of his creation. And so, at the end of the day, if we can find these breakthroughs to help us have a cleaner environment, I’m all for it.”

It was not immediately clear whether he accepts that humans play a role in global warming.

John Kasich, left, and Rand Paul. (Photos: AP)

Rand Paul, U.S. senator from Kentucky

Anthropogenic climate change: science inconclusive

Rand Paul has voted against laws that acknowledge climate change is a fact or that recognize human activity as a primary factor driving it.

During an appearance on “Real Time With Bill Maher,” Paul said there is abundant evidence that carbon has been increasing since the Industrial Age, but there needs to be a balanced solution that takes job loss from government regulation into account.

“I’m not against regulation; I think the environment has been cleaned up dramatically through regulations on emissions, as well as clean water over the last 40 or 50 years, but I don’t want to shut down all forms of energy such that thousands and thousands of people lose jobs,” he said.

Paul says the science behind climate change is inconclusive and that many environmentalists are alarmists.

“If we’re going to say the Statue of Liberty’s drowning, that’s alarmist,” he said. “And we just can’t get to any kind of middle ground.”

Rick Perry, former Texas governor

Anthropogenic climate change: science inconclusive

Rick Perry has said many times that the science of climate change is inconclusive.

“The idea that we would put Americans’ economy at jeopardy based on scientific theory that’s not settled yet to me is nonsense,” he said during one of the 2012 Republican presidential debates. “Just because you have a group of scientists who stood up and said, ‘Here are the facts.’ Galileo got outvoted for a spell.”

After Pope Francis’ call for dramatic action against climate change, a spokesperson for Perry released a statement saying, “Gov. Perry believes the climate is always changing, but it’s not clear what role humans have in it.”

Rick Perry, left, and Chris Christie. (Photos: AP)

Chris Christie, New Jersey governor

Anthropogenic climate change: real

Chris Christie has said the existence of global warming is undeniable and he thinks humans contribute to it.

“In the past I’ve always said that climate change is real and it’s impacting our state. There’s undeniable data that CO2 levels and other greenhouse gases in our atmosphere are increasing,” he said during a press conference in May 2011.

Christie conceded that he is not a scientist and cannot claim to fully understand the issue. But, he added, “When you have over 90 percent of the world’s scientists who have studied this stating that climate change is occurring and that humans play a contributing role, it’s time to defer to the experts.”

During a town hall meeting in Iowa, however, Christie said he was not sure whether climate change contributed to the hurricane that ravaged the New Jersey coastline in late October 2012, the Washington Times reported.

“I don’t know, nor has anybody else proven to my satisfaction, that it is climate change that is causing some of these storms,” he said. “I don’t know what it is. And I haven’t seen anything, at least at this point, that’s definitive to me that it was climate change that caused Superstorm Sandy.”

Rick Santorum, former U.S. senator from Pennsylvania

Anthropogenic climate change: hoax

In February 2012, Rick Santorum said climate change is a hoax and advocated for an energy plan that relies heavily on fossil fuels, the Colorado Independent reported.

“We were put on this earth as creatures of God to have dominion over the earth, to use it wisely and steward it wisely, but for our benefit not for the earth’s benefit,” he told the crowd, according to the independent news site.

In early June, when asked about the pope’s stance on WPHT, Santorum said the church has been on the wrong side of scientific controversies in the past and should stick to theology.

“The church has gotten it wrong a few times on science, and I think we’re probably better off leaving science to the scientists and focus on what we’re really good on, which is theology and morality,” he said.

Rick Santorum, left, and Mike Huckabee. (Photos: AP)



Mike Huckabee, former Arkansas governor

Anthropogenic climate change: science inconclusive

On NBC’s “Meet the Press” in June, Mike Huckabee invoked the decades-old conjecture of global cooling to suggest that the science is not conclusive concerning climate change.

The notion of global cooling, though popular with some segments of the media, had little support within the scientific community during its sensationalist heyday in the 1970s.

“Whether it’s man-made or not, I know that when I was in college, I was being taught if we didn’t act very quickly that we were going to be entering a global freezing,” Huckabee said. “And, you know, go back and look at the covers of Time and Newsweek from the early ‘70s. And we were told if we didn’t do something by 1980, we would be popsicles. Now we’re all told we’re all burning up. Science is not as settled on that as is it on some things.”

Bobby Jindal, Louisiana governor

Anthropogenic climate change: science inconclusive

Bobby Jindal’s energy plan from September 2014 said the climate is perpetually changing and questioned the role humans play in it.

The plan calls for strategies to mitigate “whatever climate changes may occur.” It also warns against “name-calling and grandstanding” when dealing with the issue while characterizing many liberals as intolerant, close-minded and arrogant.

“Global warming has become a religion for many on the Left,” his plan reads. “For most radical environmentalists, their response to any questioning of their views on climate change is simply to yell ‘Heretic!’ This is not a logical, rational, or scientific way of approaching public policy.”

Bobby Jindal, left, and George Pataki. (Photos: AP)

George Pataki, former New York governor

Anthropogenic climate change: position unclear

George Pataki once co-chaired the Council on Foreign Relations Independent Task Force on Climate Change.

But the biography on his official website does not mention his work on this issue, and he has not addressed it recently.

With the Republican primaries nearly half a year away, it might be too early to say where Pataki will fall this time around.

Lindsey Graham, U.S. senator from South Carolina

Anthropogenic climate change: real

Lindsey Graham speaks during a pre-debate forum at the Quicken Loans Arena on Thursday, Aug. 6, in Cleveland. (Photo: Andrew Harnik/AP)



Lindsey Graham, who represents a coastal state that will be battered by both sea-level rise and changes in hurricane intensity, has said on multiple occasions that man-made climate change is real and issued challenges to his own party to take it seriously.

During a June appearance on CNN, Graham said the Republican Party does not have an environmental policy — just an energy policy.

“Here’s a question you have to ask everyone who is running as a Republican: What is the environmental policy of the Republican Party? When I ask that question, I get a blank stare,” he said.

Graham said that if he were elected president, he would deal with global warming in a fiscally responsible way that is friendly to business.

“We are going to find oil and gas that we own because we are going to use fossil fuels for a long time to come, but it is OK to set lower carbon targets,” he said.

When asked if man-made climate change is real, Graham replied, “Yes I do. Absolutely. When 90 percent of doctors say you have a problem, do you listen to the one?”

Who our nation selects as the next commander in chief could very well affect whether the United States takes a leadership role or a backseat in the international response to this ongoing problem.

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