A draft report on the science of climate change estimates that it is “extremely likely” that more than half of the rise in temperatures over the past four decades has been caused by human activity. This activity, it estimates, is responsible an increase in global temperatures of 1.1 to 1.3 degrees Fahrenheit from 1951 to 2010.
“Many lines of evidence demonstrate that human activities, especially emissions of greenhouse [heat trapping] gases, are primarily responsible for the observed climate changes,” notes the Climate Science Special Report, which was available on request during a public comment period earlier this year but which received little attention until it was reported on by The New York Times this week. “There are no alternative explanations, and no natural cycles are found in the observational record that can explain the observed changes in climate,” said the report.
Penned by scientists at 13 federal agencies this year, the draft report is a special science section of The National Climate Assessment, which is congressionally mandated every four years. The National Academy of Sciences has signed off on the draft report, and it now awaits permission from the Trump administration to officially release the document.
The draft report suggests that even if humans immediately stopped emitting greenhouse gases into the atmosphere, the world would warm at least an additional 0.50 degrees Fahrenheit (0.30 degrees Celsius) over this century compared with today. More greenhouse emissions will lead to higher temperatures.
The draft study follows reports by The Hill that staffers at a U.S. Department of Agriculture were told earlier this year to avoid the term “climate change” in communications and to use phrases like “weather extremes” instead.
“We won’t change the modeling, just how we talk about it,” Bianca Moebius-Clune, the Natural Resources Conservation Service’s director of soil health, wrote in an e-mail to staff.
On Tuesday, the National Oceanic and Atmospheric Administration reported that the United States experienced its second warmest year to date and 10th warmest July on record.
Court Extends Delay on Clean Power Plan; Vacates HFC Rule
In a 2–1 decision, the U.S. Court of Appeals for the District of Columbia Circuit found Tuesday that the U.S. Environmental Protection Agency (EPA) does not have the authority to enact an Obama-era rule ending the use of hydroflurocarbons (HFCs). The 2015 EPA rule banned 38 individual HFCs or HFC blends in four industrial sectors—aerosols, air conditioning for new cars, retail food refrigeration and foam blowing—under the Significant New Alternatives Policy (SNAP) program (subscription).
A lawsuit—Mexichem Fluor, Inc. v. EPA—challenged EPA’s use of SNAP, saying that HFCs do not deplete the ozone. On Tuesday, the court found that because HFCs are not ozone-depleting substances, the EPA could not use section 612 of the Clean Air Act to ban them.
“However much we might sympathize or agree with EPA’s policy objectives, EPA may act only within the boundaries of its statutory authority. Here, EPA exceeded that authority,” Judge Brett Kavanaugh wrote for the court. “Indeed, before 2015, EPA itself maintained that Section 612 did not grant authority to require replacement of non-ozone-depleting substances such as HFCs. EPA’s novel reading of Section 612 is inconsistent with the statute as written. Section 612 does not require (or give EPA authority to require) manufacturers to replace non-ozone depleting substances such as HFCs.”
Also on Tuesday, the U.S. Court of Appeals for the District of Columbia Circuit instituted a new 60-day abeyance of the long-running legal battle over the EPA’s Clean Power Plan, which would require reductions of carbon dioxide emissions from the power sector. The court order, which also directs the EPA to file status reports every 30 days, reminds the Trump administration of the 2009 endangerment finding, which means the EPA has an “affirmative statutory obligation to regulate greenhouse gases.”
In late April, the court granted an initial delay of the litigation as the White House considers how to replace it.
United States Formally Announces Intention to Withdraw from the Paris Agreement
Last week U.S. Secretary of State Rex Tillerson told U.S. diplomats to sidestep questions about conditions for the Trump administration to re-engage in the Paris Agreement, according to a diplomatic cable published yesterday by Reuters. But the communication leaves no doubt about President Trump’s intentions: “there are no plans to seek to re-negotiate or amend the text of the Paris Agreement.” Moreover, the August 4 cable instructs diplomats to let other countries know that the United States wants to help them use fossil fuels.
The cable was sent on the day that the United States formally announced its intention to withdraw from the Paris Agreement but said that it will continue to participate in international climate change negotiations during the three-year withdrawal process. The earliest date for the United States to completely withdraw from the agreement is November 4, 2020.
President Donald Trump “is open to re-engaging in the Paris Agreement if the United States can identify terms that are more favorable to it, its businesses, its workers, its people, and its taxpayers,” said the State Department memo, which noted the U.S. role in future climate talks.
“The United States will continue to participate in international climate change negotiations and meetings . . . to protect U.S. interests and ensure all future policy options remain open to the administration,” the State Department said. “Such participation will include ongoing negotiations related to guidance for implementing the Paris Agreement.”
A United Nations statement acknowledging receipt of the notice from the United States reiterated Secretary-General António Guterres’ disappointment in the decision.
“It is crucial that the United States remains a leader on climate and sustainable development. Climate change is impacting now,” said Guterres spokesman Stéphane Dujarric.
Signatories to the Paris Agreement vowed to keep the worldwide rise in temperatures “well below” two degrees Celsius (3.6 degrees Fahrenheit) from pre-industrial times and to “pursue efforts” to hold the increase under 1.5 degrees Celsius. The U.S. pledge, under former President Barack Obama, was a cut in U.S. greenhouse gas emissions of as much as 28 percent from 2005 levels by 2025.
Prior to release of the climate policy guidance cable, the Trump administration’s reiteration of plans to depart from the Paris climate deal had raised questions about what “re-engaging” in the deal meant and how U.S. participation in climate talks could play out (subscription). With regard to negotiations, the Trump administration could adopt an obstructionist role by pushing for measures to enable reduction of emissions-cut ambitions. Or it could play a constructivist role by advancing rules for transparency (the United States and China co-chair the working group writing those rules). Other areas in which the Trump administration could exert its influence include emissions reporting requirements, monitoring land-use change and developing market mechanisms.
The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.