GOP Sen. Ron Johnson falsely claimed Greenland only recently froze and now admits he has 'no idea' about its history

GOP Sen. Ron Johnson falsely claimed Greenland was named for its once-green landscapes.

Johnson said to The New York Times last week that he had "no idea" how Greenland got its name.

The senator has rejected the science showing that climate change is caused by human activity.

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In an attempt to undermine climate science, Sen. Ron Johnson falsely claimed in 2010 that Greenland — a largely ice-covered island — was named for its once-green landscapes.

Johnson, a Wisconsin Republican, told The New York Times last week that he had "no idea" how Greenland got its name.

"You know, there's a reason Greenland was called Greenland," Johnson told Madison news outlet WKOW-TV in 2010. "It was actually green at one point in time. And it's been, you know, since, it's a whole lot whiter now so we've experienced climate change throughout geologic time."

In reality, Erik Thorvaldsson, a Viking settler also known as Erik the Red, gave Greenland a misleading name in the hopes of attracting Europeans to the island. The Danish territory has been covered in ice and glaciers for at least 2.5 million years.

"I could be wrong there, but that's always been my assumption that, at some point in time, those early explorers saw green," Johnson told The Times last week. "I have no idea."

Some of those who deny the scientific consensus on climate change spread the myth that ice ages and warm periods between them prove that the warming the Earth is experiencing is natural. Johnson has repeatedly rejected the science showing that climate change is overwhelmingly caused by human activity. He's falsely claimed that global warming is caused by sunspots and that there's nothing humans can do to reverse the phenomenon.

"If you take a look at geologic time, we've had huge climate swings," Johnson told the Milwaukee Journal Sentinel in a 2010 interview. "I absolutely do not believe that the science of man-caused climate change is proven, not by any stretch of the imagination. I think it's far more likely that it's just sunspot activity or something just in the geologic eons of time where we have changes in the climate."

He went on: "The Middle Ages was an extremely warm period in time too, and it wasn't like there were tons of cars on the road."

Johnson also said that attempting to reverse climate change is a "fool's errand" that would wreck the economy.

"I don't think we can do anything about controlling what the climate is," he said.