The draft report, which has undergone extensive review, estimates that human impact was responsible for an increase in global temperatures of 1.1 to 1.3 degrees Fahrenheit from 1951 to 2010.
"Many lines of evidence demonstrate that human activities, especially emissions of greenhouse (heat trapping) gases, are primarily responsible for recent observed climate changes," the report notes. "There are no alternative explanations, and no natural cycles are found in the observational record that can explain the observed changes in climate."
That counters what Environmental Protection Agency Administrator Scott Pruitt and Energy Secretary Rick Perry have said.
It remains unclear how the White House — which announced in June that it would pull out of the Paris climate accord — will handle the report. Many scientists are looking at it as a test case of the administration's attitude toward science in general.
"The current situation will provide an acid test of whether the Trump administration is open to hearing the scientific truth about climate change or is so much in the thrall of fossil fuel interests that they are fixated on hiding the reality from the public," Michael Oppenheimer, a professor of geosciences and international affairs at Princeton University, said Monday night.
The Climate Science Special Report is a key element of the National Climate Assessment, which, according to the 1990 Global Change Research Act, is supposed to be issued every four years. However, the assessment has come out only three times. The 2000 assessment, finalized under President Bill Clinton, came under attack once George W. Bush took office. Bush administration officials that aspects of the data analysis were flawed.
Trump administration officials received a copy of the most recent version of this report several weeks ago, according to senior administration officials.
The New York Times reported on the latest draft late Monday. The Washington Post subsequently obtained a third draft of the report. The version at the White House is the fifth draft, but people familiar with both versions say there is no substantive difference.
The report touches on a wide variety of issues, such as receding Arctic ice and an increase in the acidification of the oceans that is "unparalleled in at least the past 66 million years."
It also dismisses talk of a so-called hiatus in global warming, noting that the most recent years reinforce longer-term trends. Instead, the report says, the United States faces temperature increases of 2.5 degrees Fahrenheit over the next few decades "even under significantly reduced future emissions." And the record-setting temperatures of recent years will become "relatively common in the near future."
Juliet Eilperin contributed to this report.