A new federal climate change report, by scientists from 13 federal agencies, concludes that the country is already feeling the effects of climate change. The report, which contradicts the position of President Trump and members of his cabinet, who argue that the science of climate change as a result of human activities is still unsettled. Precariously, the report is awaiting approval by the administration.
A draft of the report was uploaded to a nonprofit digital library in January, gaining newfound attention when it was published by the New York Times this week.
“Evidence for a changing climate abounds, from the top of the atmosphere to the depths of the oceans,” according to the draft. It also notes the thousands of studies that have documented the effects of climate change. “Many lines of evidence demonstrate that human activities, especially emissions of greenhouse (heat-trapping) gases, are primarily responsible for recent observed climate change.”
The report is a special science section of the National Climate Assessment, mandated by congress every four years. The National Academy of Sciences has signed off on the report, which is now awaiting the go-ahead from the Trump administration before it is officially released.
Katherine Hayhoe, professor of political science at Texas Tech University, and one of the scientists involved in the report, said it was one of “the most comprehensive climate science reports” to date. Another scientist, speaking anonymously to the New York Times, said he was among a number of scientists concerned the administration would suppress the report.
The researchers said that even if carbon emissions were halted immediately, the planet would still face 0.50 degrees Fahrenheit (0.30 degrees Celsius) of warming. As things stand now, the report predicts warming by as much as 2 degrees Celsius.
One difficulty in monitoring climate change has been determining when extreme weather is related to climate change. A field of study, called “attribution science” has sought to assess this causality. The report says that it is possible to attribute some extreme weather directly to climate change. With a medium degree of confidence, the report links higher temperatures in the Northern and Western United States, and noted that temperatures in Alaska and the Arctic are warming at rates twice as fast as the global average.
Environmental Protection Agency administrator Scott Pruitt has said he does not believe in a connection between global warming and carbon emissions. His agency is one of 13 that must approve the report by August 18th.
Michael Oppenheimer, a Princeton University professor of geoscience and international affairs, who was not involved in the study, said: “It’s a fraught situation. This is the first case in which an analysis of climate change of this scope has come up in the Trump administration, and scientists will be watching very carefully to see how they handle it.”