The rapid pace of global climate change is almost certainly driven by human activity, according to a US government report, which contradicts assertions by President Donald Trump and members of his administration.
"For the warming over the last century, there is no convincing alternative explanation supported by the extent of the observational evidence," said the report by a group of more than 50 US government scientists released on Friday.
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The report, required by congress every four years, was written by scientists from government bodies such as the Environmental Protection Agency and the National Oceanic and Atmospheric Administration.
Future temperatures will depend heavily on the amount of carbon dioxide emitted into the atmosphere, the report said. Global average sea levels are expected to rise "at least several inches in the next 15 years" because of rising temperatures, it added.
Trump has repeatedly called climate change a hoax and in June announced that he would withdraw the US from a global pact to combat it, calling the deal too costly for the US economy.
His Environmental Protection Authority (EPA) administrator, Scott Pruitt, has also expressed doubts about the causes of climate change, at one point saying he did not believe carbon dioxide from human activity is the primary driver.
White House spokesman Raj Shah said: "The administration supports rigorous scientific analysis and debate and encourages public comment on the draft documents being released today."
Officials at the EPA did not immediately respond to requests for comment.