U.S. report: 'No convincing' explanation for climate change other than humans
A new report released by the Trump administration says human activities, specifically the emission of greenhouse gases, are the dominant cause of the warmest period in the history of modern civilization.
"For the warming over the last century," the concludes, "there is no convincing alternative explanation supported by the extent of the observational evidence."
"This period is now the warmest in the history of modern civilization," said study co-author Katharine Hayhoe of Texas Tech.
Some of the stark facts in the report:
- Global annually averaged surface air temperature has increased by about 1.8 degrees Fahrenheit from 1901 to 2016.
- Global average sea level has risen by about 7 to 8 inches since 1900 with nearly half of that (3 inches) since 1993. The rate of rise that is greater than during any preceding century in at least 2,800 years.
- Global average sea levels are expected to continue to rise by at least several inches in the next 15 years and by 1 to 4 feet by 2100.
It's "extremely likely" — meaning with 95 to 100 percent 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.
This is the first National Climate Assessment since 2014. The report is designed to collect new evidence and summarize the current state of knowledge on climate science.
The release of the report is mandated by a 1990 law, and the White House didn't attempt to prevent its release. The conclusions reached, however, run opposite of the opinions from some important administration figures.
Environmental Protection Agency head Scott Pruitt, who sued the agency frequently in his former role as Oklahoma's attorney general, has expressed doubts about humans causing climate change, as has Energy Secretary Rick Perry.
Trump himself previously called climate change a hoax invented by the Chinese to harm the U.S. economy. In the first year of his presidency, he has worked to dismantle regulations put in place to lower the nation's carbon footprint.
The Associated Press contributed.