In recent debates hosted by theDenver Post, candidates were asked a series of yes-or-no questions by the moderators. One of those questions was, 鈥淒o you believe humans are contributing significantly to climate change?鈥� Republican gubernatorial challenger Bob Beauprez and sixth district incumbent Republican Congressman Mike Coffman both answered 鈥渘o,鈥� putting them in clear contrast with the established scientific consensus on the issue.听
The coal-fired Craig Station power plant in northwest Colorado is the state's largest single source of CO2 emissions. (Wikimedia Commons)
Both tried to clarify their answer later in the debate.
鈥淎re we going to end or alter the path that Earth鈥檚 evolution is going to take? I don鈥檛 think so,鈥澨�.
鈥淥n the climate change issue, I just think the science is not quite settled,鈥澨�.
While Beauprez鈥檚 campaign website does not mention climate change,听. It states, 鈥淭he role that carbon emissions, from human activity, have on climate change is still a subject of debate.鈥�
In an interview with听CU News Corps, Kevin Trenberth, a climate scientist at the National Center for Atmospheric Research, called this statement 鈥渆mphatically wrong.鈥�
鈥淭he human component is so far outside natural variability in many ways,鈥� Trenberth said. 鈥淭he estimates suggest that any natural variability has, if anything, worked against the warming.鈥�
The scientific consensus that humans are contributing significantly to climate change is well established, and has been for quite some time. In 2006,听, 鈥淭he scientific evidence is clear: global climate change caused by human activities is occurring now, and it is a growing threat to society.鈥� In 2012,听, 鈥淚t is clear from extensive scientific evidence that the dominant cause of the rapid change in climate of the past half century is human-induced increases in the amount of atmospheric greenhouse gases.鈥� In fact,听听from around the world hold the position that human activity is causing climate change.
Furthermore, a 2010听听published in听the Proceedings of the National Academy of Sciences听found that 97 to 98 percent of the climate researchers most actively publishing in the field support the basic tenets of human-caused climate change. In another听, researchers examined nearly 12,000 studies on climate change between 1991 and 2011 and found that, among those expressing a position, 97.1 percent endorsed the consensus position that humans are causing climate change.
While uncertainties remain regarding exactly how climate change will manifest itself in the coming decades and centuries, there is virtually no debate within the scientific community on whether human activity is the dominant cause of recent warming, putting Bob Beauprez and Mike Coffman鈥檚 debate comments firmly out-of-step with the scientific literature on the subject.