Scientists from 13 federal agencies lay out evidence that climate change primarily due to human activities

Just days after the Trump administration submitted a letter to the United Nations withdrawing the United States from the Paris climate accord, a leaked government draft report showed that climate change is already having an impact on the country.

Temperatures have risen dramatically since 1980, according to the report that was published by The New York Times on Monday and renewed on Tuesday.

The US Global Change Research Program Climate Science Special Report, compiled by a group of scientists from 13 federal agencies, shows that recent decades have been the warmest of the past 1,500 years and concludes that people in the United States are feeling the effects of climate change right now.

"Many lines of evidence demonstrate that human activities, especially emissions of greenhouse (heattrapping) gases, are primarily responsible for recent observed climate change," the authors said.

The report, part of the National Climate Assessment, was congressionally mandated to take place every four years since 1990. It was supposed to be approved by the Trump administration before being released publicly.

The report's message contradicts the opinion held by US President Donald Trump and many of his Cabinet members.

Trump has called the concept of global warming a "Chinese hoax" that was "created by and for the Chinese in order to make US manufacturing non-competitive".

On Tuesday, both the White House and the Environmental Protection Agency said the draft has been in the public domain for months.

'Major disappointment'

On Friday, US officials submitted a letter to inform the UN that the US will withdraw from the Paris Agreement. The letter, sent to UN Secretary General Antonio Gutteres by US Ambassador to the UN Nikki Haley, left the door open to reengage if the terms improved for the US.

Trump announced his decision to withdraw from the Paris accord on June 1, describing it as bad for the US economy and jobs. As part of the Paris agreement, the US had pledged to cut its greenhouse gas emissions by 28 percent from its 2005 levels by 2025.

The letter is in fact not qualified as a letter for formal withdrawal. Under the rules, the US can only submit such a letter in 2019. The earliest date for the US to completely withdraw from the accord is Nov 4, 2020, one day after the 2020 US presidential election.

Guterres called the US decision a "major disappointment for the global effort to reduce greenhouse gas emissions and promote global security", and he would welcome any efforts toward the US' reengagement.

Andrew Light, a distinguished senior fellow in the global climate program of the World Resources Institute, said that the report "really represents the best that we know in terms of climate science and we hope the administration will listen to it".

Light said the biggest damage inflicted by the US withdrawal will be on the US because there is a huge market in clean energy investment around the world.

Speaking on Meet the Press on NBC on Sunday, California Governor Jerry Brown said his state and other states are forming a climate alliance. "In terms of climate change, it is an existential threat," he said.

"It is not a hoax. It was not created in China. It is something that the majority, 95 percent of scientists believe in," Brown said.

chenweihua@chinadailyusa.com