Federal report points to human activity as prime cause of climate change

Aug. 8 (UPI) -- A new federal report, which is awaiting White House approval, concludes that human activity is "primarily responsible" for a drastic rise in the average temperature in the United States in the last four decades.

The Climate Science Special Report was authored by scientists from 13 federal agencies -- including the National Oceanic and Atmospheric Administration, NASA and the White House's Office of Science and Technology Policy -- and several academic institutions.

"The global climate continues to change rapidly compared to the pace of the natural changes in climate that have occurred throughout Earth's history. Trends in globally-average temperature, sea-level rise, upper-ocean heat content, land-based ice melt and other climate variables provide consistent evidence of a warming planet," the authors wrote.

The report said the frequency and intensity of heavy precipitation and extreme heat occurring in most of the world is consistent with expected physical responses to a warming climate, which will continue to intensify such weather events.

"Many lines of evidence demonstrate that human activities, especially emissions of greenhouse gases, are primarily responsible for the observed climate changes in the industrial era," the authors added. "There are no alternative explanations, and no natural cycles are found in the observational record that can explain the observed changes in climate."

President Donald Trump and his administration received a copy of the report weeks ago, The Washington Post reported. The assessment is mandated by Congress every four years. A copy of this year's report was first obtained by The New York Times.

The report's content is at odds with the Trump administration's position -- and at times rejection -- of the scientific community's belief that human activity causes climate change.

Trump has both supported and rejected the concept of human-caused climate change. In 2012, he said the "concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive." Last year, he said he thinks "there is some connectivity" between human activity and climate change.

Though Trump has not formally expressed a definitive stance on global warming issues, his administration has taken actions that seemingly reject the notion that human activity contributes to climate change.

The U.S. Department of State on Friday gave the United Nations notice of the United States' intent to withdraw from the Paris climate change agreement.

Trump, who has previously labeled climate change a "hoax," announced in April that the United States would abandon the agreement, saying it's a "bad deal" for the domestic economy. The landmark 195-nation pact sets out stringent standards to restrict carbon emissions and other greenhouse gases that scientists say contribute to climate change.

"Global climate is projected to continue to change over this century and beyond. The magnitude of climate change beyond the next few decades depends primarily on the amount of greenhouse (heat trapping) gases emitted globally and the sensitivity to Earth's climate to those emissions," the report states.