Case for climate change grows ever stronger But will Trump administration change the draft National Climate Assessment?: Our view

The Editorial Board | USA TODAY

Show Caption Hide Caption It's official: 2016 is the Earth's hottest year Last year was Earth's warmest on record, according to NOAA.

Corrections & clarifications: An earlier version of this editorial incorrectly characterized carbon dioxide levels in the atmosphere.

Could proof grow any more powerful that humanity is responsible for a dangerously warming planet? Scientists studying Earth's atmosphere and oceans are finding ever more troubling evidence.

Last year was the hottest on record, according to a report late last week from the National Oceanic and Atmospheric Administration. The report, by more than 450 scientists from 60 nations, also found that greenhouse gases in the atmosphere and global sea levels are at their highest levels on record.

Just as troubling were draft findings destined for the quadrennial National Climate Assessment. Scientists from 13 federal agencies found that a rapid rise in temperatures since the 1980s in the United States represents the warmest period in 1,500 years.

The impacts from human-caused warming are no distant threat, the scientists concluded, but are punishing populations right now with weather made worse by climate change: more heat and drought in the American Southwest, larger and fiercer storms along the Pacific, and greater rainfall elsewhere.

"Many lines of evidence demonstrate that human activities, especially emission of greenhouse gases, are primarily responsible," the draft says. "There are no alternative explanations."

OPPOSING VIEW: Don’t hype draft climate studies

The stark threat from climate change is why nearly 200 nations joined together under the Paris Agreement, signed last year, to collectively curb emissions of heat-trapping carbon dioxide. It's also why 40 countries, and a group of Republican elder statesmen in the United States, support worthy plans for a refundable carbon tax that puts a price on greenhouse gas emissions created by the burning of fossil fuels.

The question now is how the Trump administration, which is stocked with climate skeptics and is pulling the United States out of the Paris accord, will react to the latest scientific findings. The White House could decide as early as Friday whether to order changes in the draft National Climate Assessment report.

Environmentalists such as Al Gore and former New York mayor Michael Bloomberg say Trump's rejection of the science only compels state and local governments to act more aggressively to head off catastrophic climate change.

There is that hope. As the world has begun turning to cleaner burning fuels and renewable energy, it appears that annual emissions of carbon dioxide into the atmosphere are leveling off, even as the amount of carbon dioxide in the atmosphere and global temperatures continue to rise.

But much damage can still be done. A recent study has shown that just four years of Trump's recalcitrant environmental policies would add an additional 12 billion metric tons of carbon dioxide to the atmosphere.

It's bad enough when President Trump defies the truth when he talks about millions of undocumented immigrants voting against him in the election, or the crowd size at his inauguration. At least those falsehoods provide grist for late-night comics.

The same cannot be said for defying the overwhelming scientific consensus about human-caused climate change and actively working against global efforts to stave off calamity. That's placing the future of the planet, and the lives of its inhabitants, in jeopardy.

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