WASHINGTON — Directly contradicting President Donald Trump, a draft report produced by 13 federal agencies concludes that the United States is already feeling the negative impacts of climate change, with a stark increase in the frequency of heat waves, heavy rains and other extreme weather over the last four decades.

The preliminary report summarizes the current state of the science for the upcoming National Climate Assessment. Trump and his Cabinet have expressed public doubts that the warming is being primarily driven by man-made carbon pollution and will have serious consequences for Americans.

An early version of the report, a copy of which was obtained by The Associated Press, was distributed widely in December for review by leading scientists. The New York Times published a copy Monday.

The U.S. Global Change Research Program, which will edit and produce the final report, did not respond to phone and emails seeking comment on Tuesday.