(CN) – In 2009, the Environmental Protection Agency under President Barack Obama announced that greenhouse gasses endangered public health – a finding that formed the legal basis for fighting climate change under the Clean Air Act. Nearly a decade later, the peril from climate change is clearer than ever. And scientists are fighting to justify the EPA’s endangerment finding in a new study published Thursday in the journal Science.
The Supreme Court found in the 2007 Massachusetts v. EPA that, under the Clean Air Act, the EPA must regulate greenhouse gases once it has determined the emissions endanger the health and welfare of current and future generations. The EPA issued its first such finding two years later, based on research by the U.S. Global Change Research Program, Intergovernmental Panel on Climate Change, and the U.S. National Research Council.
Since then, the evidence has only strengthened. Yet the political will to make changes has shriveled, according to Phil Duffy, the study’s lead author and former science adviser to Obama.
“Harms from greenhouse gases and manifestations from climate change are much more real now than they were nine years ago,” Duffy said. “Nine years ago they were here, but they were more in the future with potential harms. Now they are much more immediate – things like extreme weather and wildfire, which have been very vigorously tied to climate change and are much more prominent now.”
That, and the potential for Trump-era EPA administrators to try to toss out the endangerment finding, motivated Duffy to round up experts in each category of danger to review science produced after 2009.
“There have been rumblings by people inside the Trump administration, and also people outside it who they listen to, that we should revisit or overturn the endangerment finding,” Duffy said. “If there were an attempt to overturn the endangerment finding, I imagine there would be litigation, and then this would be useful – a peer-reviewed study saying evidence is even stronger than in 2009, and it was already very strong in 2009.”
Former EPA administrator Scott Pruitt repeatedly suggested repealing the endangerment finding, according to news reports. Pruitt resigned in July amid over a dozen investigations into possible misuse of office. Acting EPA Administrator Andrew Wheeler told the Washington Post shortly after he took over leadership at the agency that he considered the endangerment finding to be settled law. But Wheeler, a former coal lobbyist, has also vowed to carry out President Donald Trump’s pro-fossil fuel agenda.
“It’s a strange time now because there have been, in the last month or two, a series of high-level science reports – one from the U.N. Intergovernmental Panel on Climate Change and the National Climate Assessment – both were very stark, and both pointed out the immediacy of the impacts and the urgent need for action,” Duffy said. “So the science is very clearly pointing in one direction and yet the policies, the U.S. policies at least, are going in the exact opposite direction.”
Duffy’s results are grim.
“What has happened now is land ice sheets are melting faster than we thought,” he said. “That means sea level rise is going to be worse than we thought and meanwhile in the last nine years, we haven’t really done anything to stop it.”
The 2009 endangerment finding was based on the peril caused by greenhouse gases in seven categories: air quality; food production and agriculture; forestry; water resources; sea level rise and coastal areas; energy, infrastructure and settlements; and ecosystems and wildlife.
This time around, Duffy and the panel of 16 scientists who co-authored the study said it was necessary to add sections for ocean acidification, violence and social instability, national security and economic well-being.
“We find that the case for endangerment, which already was overwhelming in 2009, is even stronger now,” researchers wrote. “Since 2009, the amount, diversity, and sophistication of the evidence has increased dramatically, clearly strengthening the case for endangerment,” according to the paper.
Since the 2009 endangerment finding, scientists have improved their ability to attribute extreme weather events to human-caused climate change. The panel found extreme heat is likely to cause early deaths for people living in more than 200 U.S. cities. It estimated climate change caused 70 percent of recent record-setting hot and wet weather events, as well as half of recent record-setting dry spells. They pointed specifically to Hurricane Katrina, Superstorm Sandy and record rains during Hurricane Harvey as extreme events that can be “confidently attributed to historical emissions.” Such attributions “reinforce the understanding that we are already seeing impacts and the risks they bring,” the panel wrote.
Drought, catastrophic forest fires and rampant outbreaks of bark beetles threaten to transform forest ecology from coast to coast and “will profoundly disrupt U.S. forest ecosystems,” the panel wrote. Since the 2009 finding, scientists have shown that mountain snowpack is lower and melts two weeks earlier – things that “would fundamentally change the sources and timing of runoff” across the country. Rivers are lower in summer, harming threatened species like salmon and trout. And the availability of drinking water is threatened across the globe. In the U.S., water quality is in danger.
We now have a much clearer idea of how sea level rise will impact coastal cities. Estimates from the National Oceanic Atmospheric Administration place an “intermediate-low scenario” of flooding at every other day for much of the east coast and the Gulf of Mexico by 2100. The agency’s intermediate scenario is daily flooding in all U.S. coastal regions by the same year.
About 15 percent of species across all taxonomic groups face extinction by 2100, research since 2009 shows. Ocean acidification could imperil oysters and other shellfish, dissolve the coral reefs and harm the ability of fish to smell.
During the last decade, numerous studies have shown that violence between individual people, violence based on ethnicity and even coups are all more likely during extreme heat and rainfall. And melting sea ice could turn the Arctic into the next geopolitical flash point. The American military evidently takes such threats seriously: The Department of Defense has issued nearly 50 reports since 2010 considering the nexus between climate and security impacts.
Meanwhile, U.S. representatives at the U.N.’s climate change summit in Poland said the Trump administration is committed to keep using coal – the most carbon-intensive source of electricity, according to EPA data. In 2016, coal use accounted for 67 percent of U.S. emissions from electricity production, yet produced only 32 percent of the country’s electricity that year.
“Fossil fuel use is not declining, it’s continuing at a steady pace,” Steven Winberg, Trump’s assistant secretary of fossil energy, told summit attendees on Monday. “So the question is, do we continue using coal technologies that we developed in the 1970s or do we move forward with transformational coal technologies that will be near zero emitting? We can either continue using the technologies we have been using for the last 30 or 40 years, or we can springboard over those technologies and develop transformational technologies. And that’s what the fossil energy office is doing and we’re going to move forward on that.”
In contrast, during the weeks before the EPA issued the 2009 endangerment finding, Obama attended the U.S.’s summit on global warming in Copenhagen and pledged to reduce greenhouse gas emissions in 2020 to 17 percent below 2005 levels.
In 2016, the most recent year for which data is available, greenhouse gas emissions were 12 percent below 2005 levels, according to the EPA’s annual Inventory of U.S. Greenhouse Gas Emissions and Sinks.
Despite the growing alarm over the effects of climate change, Duffy said that 2009 may have been an easier time to be a climate scientist.
“It was a great period of optimism mainly because we felt we had a friend in the Oval Office. But while President Obama certainly understood the gravity and the urgency of the problem, he did not have the support of Congress. So he had to do what he could through the executive office and the endangerment finding gave him a great tool. The problem is that what can be done through executive action can be undone with executive action and that is exactly what’s happening now.”