After the devastation of Hurricane Michael and a recent United Nations report warning of a looming climate crisis, White House economic adviser Larry Kudlow and Sen. Marco Rubio on Sunday questioned the extent of human contribution to rising global temperatures.

“I think they overestimate,” Kudlow said of the U.N. report, which found that policy changes must proceed at an unprecedented pace in the next 12 years to stop temperatures from rising more than 1.5 degrees Celsius (2.7 degrees Fahrenheit) above Earth’s preindustrial temperature.

“I’m not denying any climate-change issues,” Kudlow said on ABC’s “This Week.” “I’m just saying, do we know precisely . . . things like how much of it is manmade, how much of it is solar, how much of it is oceanic, how much of it is rain forest and other issues?”

Rubio (R-Fla.), speaking on CNN about the effects of Hurricane Michael, said that sea levels and ocean temperatures have risen in a “measurable” way and that humans have played some role. But he questioned how big that role is.

“I think many scientists would debate the percentage of what is attributable to man versus normal fluctuations,” Rubio said on “State of the Union.”

The established scientific view is that the majority of global warming is caused by humans, and the recent report from the U.N. Intergovernmental Panel on Climate Change (IPCC) reinforced this conclusion.


Larry Kudlow, White House economic adviser, didn’t deny that global warming is happening, but he questioned the degree to which industry is responsible. (Joshua Roberts/Bloomberg News)

The study found that “human activities” are estimated to have caused 1 degree Celsius (1.8 degrees Fahrenheit) of warming since the late 19th century, and it went on to note that “estimated [human-caused] global warming matches the level of observed warming to within ±20 percent.”

On ABC, Sen. Bernie Sanders (I-Vt.) called Kudlow’s comments “so irresponsible, so dangerous.”

“We are in crisis mode, and you have an administration that virtually does not even recognize the reality of climate change, and their policies, working with the fossil fuel industry, are making a bad situation worse,” Sanders said.

The debate took place as Florida’s state government leads the recovery effort following Michael, which hit the panhandle last week as a Category 4 storm. The hurricane killed more than a dozen people and flattened areas such as Mexico Beach and Panama City, which Rubio said will have to be “totally rebuilt.”


Sen. Jeff Flake (R- Ariz.). (Jacquelyn Martin/AP)

While scientists hesitate to attribute any one event to climate change, Michael is the kind of event scientists say will take place more frequently unless countries sharply reduce their carbon emissions.

The storm coursed over unusually warm ocean waters and rapidly intensified just before landfall, a phenomenon that some research suggests will occur more frequently in a warmer climate. The storm surge was higher and traveled farther inland than it would have had the same storm arrived a century ago.

Rubio acknowledged that his state, with its nearly 8,500 miles of coastline, is already seeing the effects of rising sea levels and warmer temperatures.

Beyond Michael, those effects have been extensive.

The Florida coral reef, one of the largest in the world, was bleached in 2014 and 2015 amid warmer waters. Nuisance flooding appears to be baked into the Miami-Dade real estate market.

Rubio was most blunt about sea-level rise, describing it as an unavoidable effect of warming temperatures. Scientists agree, predicting that sea levels could rise for centuries as the planet adjusts to warmer temperatures.

“No matter what we do, no matter what we do with laws, if tomorrow we stopped all carbon . . . this trend would still continue,” Rubio said of sea-level rise.

He added that while he has pushed for “mitigation strategies” to protect Florida’s coastal communities, he would not support policies that would “destroy our economy.”

“There’s a reality here, and there’s a balance on that end of it that we need to be focused on,” Rubio said.

The IPCC, the scientific community’s leading body on climate change, said that rapid changes to hold global warming to 1.5 degrees Celsius would cost about half a trillion dollars per year more around the world than those required to hold warming to 2 degrees Celsius. Faster action, including changes to energy, transportation and other systems, will indeed cost more money, it said.

But the impacts of climate change cost a lot, too. The study cited research suggesting the cost of allowing warming to reach 2 degrees Celsius, rather than holding it at 1.5 Celsius, could be between .35 and .6 percent of U.S. gross domestic product.

Sen. Jeff Flake (R-Ariz.), who is not running for reelection, called the IPCC report “pretty dire” and urged Republicans to take the lead in battling rising temperatures as a matter of political necessity.

“I hope that we can move along with the rest of the world and address this,” Flake said on ABC.

“It’s going to be challenging . . . but there are things that we can do and should do, and I think Republicans need to be at the forefront if we want to keep our place and keep our seats,” he said.