House Republicans rejected amendments offered Tuesday by Democrats that called on Congress to accept the scientific consensus that climate change is occurring, it is caused in large part by human activity and it is a threat to human health.

The amendments, offered at an Energy and Commerce Committee markup of legislation to block Environmental Protection Agency climate change rules, are part of an effort by House Democrats to get Republicans on the record on climate science.

Committee ranking Democrat Rep. Henry Waxman (D-Calif.) offered an amendment Tuesday that called on Congress to agree that climate change is occurring. The amendment failed on a party-line vote of 20-31. No Republicans voted for the amendment.

The amendment says that "Congress accepts the scientific finding of the Environmental Protection Agency that 'warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level.'"

"This finding is so obviously correct that there should be no need to offer the amendment," Waxman said.

The broad consensus among scientists is that climate change is occurring in large part because of human activity.

House Republicans also rejected an amendment offered by Rep. Diana DeGette (D-Colo.) Tuesday that called on Congress to accept the scientific consensus that climate change is occurring in large part due to human activity. The amendment failed in a 21-30 party-line vote. No Republicans voted in favor of the amendment.

DeGette's amendment says “’the scientific evidence is compelling’ that elevated concentrations of greenhouse gases resulting from anthropogenic emissions ‘are the root cause of recently observed climate change.’”

“I would urge my colleagues to support this amendment and reject any kind of fuzzy science,” DeGette said.

Rep. Jay Inslee (D-Wash.) offered a third amendment that says human-caused climate change is a threat to public health and welfare. That amendment also failed on a party-line vote of 21-31.

Republicans, in response to the amendments, took issue with climate science Tuesday.

"My good friend from California tries to make it clear that the science is settled. I would say it’s not settled," Rep. Joe Barton (R-Texas) said of Waxman's amendment.

The GOP rejection of Waxman's amendment shows "what it means to be on the wrong side of history and the wrong side of science," Rep. Jan Schakowsky (D-Ill.) said.

But Rep. Ed Whitfield (R-Ky.), the chairman of the panel’s Energy and Power Subcommittee, said Republican legislation to block EPA climate rules is not about climate science. It is instead about preventing the EPA from passing climate regulations that Republicans say will hobble the economy.

“For us to be sitting around talking about the science, I think it’s a strong argument to be made on the other side, but the issue here is that the Clean Air Act is not the appropriate vehicle to regulate something like this,” Whitfield said.

“I think my friend from Kentucky made a good argument about why he doesn’t want to see regulation, but it wasn’t a very convincing argument about why you would reject this amendment,” Waxman countered.

“You can disagree with how EPA acts, but you shouldn’t argue therefore that we shouldn’t even consider the science," he said. "This is science denial. It’s not worthy of this committee.”

This story was updated at 12:01 p.m.

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