http://www.scmp.com/news/world/united-states-canada/article/2118396/us-report-contradicts-trump-team-claiming-global
A massive US report concludes the evidence of global warming is stronger than ever, contradicting a favourite talking point of top Trump administration officials, who downplay human’s role in climate change.
The report released on Friday is one of two scientific assessments required every four years. A draft showing how warming affects the US was also published.
Despite fears by some scientists and environmental advocates, David Fahey of the National Oceanic and Atmospheric Administration and several authors said there was no political interference or censoring of the 477-page final report.
“A lot of what we’ve been learning over the last four years suggests the possibility that things may have been more serious than we think,” said Robert Kopp of Rutgers University, one of dozens of scientists inside and outside the government who wrote the reports.
Energy Secretary Rick Perry and Environmental Protection Agency chief Scott Pruitt have repeatedly said carbon dioxide isn’t the primary contributor to global warming.
It’s “extremely likely” – meaning with 95 to 100 per cent certainty – that global warming is man-made, mostly from the spewing of carbon dioxide into the atmosphere from the burning of coal, oil and natural gas, scientists concluded.
“Over the last century, there are no convincing alternative explanations,” the report said.
Scientists calculated that human contribution to warming since 1950 is between 92 per cent and 123 per cent. It’s more than 100 per cent on one end, because some natural forces – such as volcanoes and orbital cycle – are working to cool Earth, but are being overwhelmed by the effects of greenhouse gases, said study co-author Katharine Hayhoe of Texas Tech.
“This period is now the warmest in the history of modern civilisation,” she said.
