WASHINGTON — EPA Administrator Scott Pruitt said a newly released government report that lays most of the blame for the rise of global temperatures to human activity won't deter him from continuing to roll back the Obama-era Clean Power Plan, a major rule aimed at combating climate change.

"We’re taking the very necessary step to evaluate our authority under the Clean Air Act and we’ll take steps that are required to issue a subsequent rule. That’s our focus," Pruitt said in an interview with USA TODAY Tuesday. "Does this report have any bearing on that? No it doesn’t. It doesn’t impact the withdrawal and it doesn’t impact the replacement."

The Trump administration last month began the formal process of dismantling the Clean Power Plan rule intended to curb carbon emissions that contribute to global warming. Pruitt, who sued to block it as Oklahoma's attorney general, said Congress never gave the EPA the Obama administration the authority to implement such a sweeping regulation.

In his first public comments since the Trump Administration released the National Climate Assessment Friday, Pruitt said the decision by the U.S. Supreme Court last year to suspend the regulation until legal challenges are resolved has "created great uncertainty" about the current regulatory framework.

The EPA is in the midst of drafting a replacement rule that will have to be as legally defensible as the very rule targeted for elimination as environmental groups are already threatening legal action.

"Our job is to administer statutes," Pruitt said, explaining the limits of what EPA can do. "We have to act (based) on the authority given to us by Congress."

President Trump has dismissed climate change as a "hoax" perpetrated by the Chinese to gain a competitive edge over the United States. A champion of the coal industry, Trump has followed through on his vow to undo the climate change agenda implemented under Obama by pulling out of the Paris Accord and withdrawing the Clean Power Plan.

The Environmental Protection Agency, under Pruitt's direction, has been at the forefront of that effort.

Pruitt's assertion that nothing has changed because of the climate report is not surprising given his steadfast opposition to the Clean Power Plan. Still, his position in the wake of what environmentalists see as powerful evidence of human-caused climate change is disappointing to critics of the administration.

David Doniger, a climate change expert with the Natural Resources Defense Council, criticized the EPA administrator for abandoning the Obama-era rule, saying the Supreme Court has "unequivocally" recognized EPA’s authority to curb carbon pollution under the Clean Air Act.

"The National Climate Assessment has sounded a five-alarm fire bell, and Scott Pruitt pretends he can’t hear it," he said. "The assessment shows unequivocally that carbon pollution is causing dangerous climate change and that our future depends on whether we cut that pollution."

The release last week of the federally mandated report prepared by the nation's top scientists every four years for the president, the Congress and the public concludes, "based on extensive evidence, that it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century."

Pruitt Tuesday downplayed the importance environmental groups have placed on the report, saying the assessment is part of the ongoing debate between scientists over the causes of and responses to warming temperatures.

"Obviously the climate is changing and has always changed, (and) humans contribute to that. Measuring with exact precision is very challenging," he said. "So I think the report (is) good to encourage an open dialogue on this."

One of the report's authors, climate scientist Katharine Hayhoe, boiled down the findings in a tweet:

The report concluded that global atmospheric carbon dioxide concentration has now passed 400 parts per million, a level that last occurred about 3 million years ago, when both global average temperature and sea level were significantly higher than today.

The only solution to the problem is to reduce the amount of greenhouse gases, especially carbon dioxide, emitted globally, the report said.

Hundreds of scientists from 13 federal agencies assessed more than 1,500 scientific studies and reports to produce the paper. The National Academy of Sciences also peer-reviewed it before release.

Other findings include:

—Global average sea level has risen by about 7-8 inches since 1900, with almost half (about 3 inches) of that rise occurring since 1993.

—Global average sea levels are expected to continue to rise — by at least several inches in the next 15 years and by 1-4 feet by 2100. A rise of as much as 8 feet by 2100 cannot be ruled out.

—Heavy rainfall is increasing in intensity and frequency globally and across the United States and is expected to continue to increase.

—The rate of daily tidal flooding is accelerating in more than 25 Atlantic and Gulf Coast cities.

—Heat waves have become more frequent in the United States since the 1960s, while extreme cold temperatures and cold waves are less frequent.

—The rate of large forest fires in the western United States and Alaska has increased since the early 1980s and is projected to further increase.

—Annual trends toward earlier spring melt and reduced snowpack are already affecting water resources in the western United States.

Doyle Rice of USA TODAY contributed

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