Environmental Protection Agency Administrator Scott Pruitt denied that climate change is the result of increased amounts of carbon dioxide, countering what the vast majority of climate and NASA scientists have claimed.
"I think that measuring with precision human activity on the climate is something very challenging to do and there's tremendous disagreement about the degree of impact," Pruitt told CNBC in an interview. "So no, I would not agree that it's a primary contributor to the global warming that we see. But we don't know that yet ... We need to continue the debate and continue the review and the analysis."
But NASA and the National Oceanic and Atmospheric Administration said in January that increased carbon dioxide is indeed a cause of higher global temperatures.
"The planet's average surface temperature has risen about 2.0 degrees Fahrenheit (1.1 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere," NASA and NOAA said.
According to NASA: "Multiple studies published in peer-reviewed scientific journals show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities. In addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position."
Scientists from NASA and NOAA also concluded that 2016 was the hottest year on record.
"Globally-averaged temperatures in 2016 were 1.78 degrees Fahrenheit (0.99 degrees Celsius) warmer than the mid-20th century mean," a Jan. 18 statement from NASA reads. "This makes 2016 the third year in a row to set a new record for global average surface temperatures."
"2016 is remarkably the third record year in a row in this series," said Gavin Schmidt, NASA's director of the Goddard Institute for Space Studies. "We don’t expect record years every year, but the ongoing long-term warming trend is clear."
Pruitt, who has denied human activity is the cause of higher global temperatures, is a Republican politician with no scientific background. During his tenure as Oklahoma's attorney general, he sued the EPA 14 times, according to The New York Times.
"He has advocated and stood up for the profits of business, be it the poultry companies or the energy industry and other polluters, at the expense of people who have to drink the water or breathe the air," said Mark Derichsweiler, who led the Oklahoma Department of Environmental Quality division that oversaw poultry-related cleanup.
While Pruitt disagrees with trained climate scientists about the climate and has been accused of prioritizing business interests over the environment, Pruitt does have at least one group that supports him: the Competitive Enterprise Institute, a lobbying group that favors limited government regulation on business interests.
"Some claim that Mr. Pruitt opposes clean air and water," CEI wrote in a Jan. 12 letter in favor of Pruitt's nomination as EPA Administrator. "This could not be further than the truth. Mr. Pruitt respects and upholds the Constitution, and understands that many of the nation’s challenges regarding clean air and water are best met at the state and local level."
Others don't believe the federalist way of government is wise when it comes to the environment, which doesn't abide by state lines.
"Pollution doesn’t respect state boundaries," said Patrick Parenteau, an environmental law professor at Vermont Law School. "States have limited ability to regulate pollution from outside the state, and almost every state is downstream or downwind from other pollution."