Study: EPA endangerment finding looks even better with age

Source: Niina Heikkinen, E&E News reporter • Posted: Friday, December 14, 2018

A new report highlights increasingly strong evidence supporting EPA’s 2009 determination that climate change hurts public health and welfare.

The research analysis, published today in the journal Science, evaluates the body of scientific work on global warming impacts on humans and the environment in the decade following the agency’s release of its endangerment finding for greenhouse gases under the Clean Air Act.

“Since 2009, the amount, diversity, and sophistication of the evidence have increased dramatically, clearly strengthening the case for endangerment,” said the report.

“New evidence about the extent, severity, and interconnectedness of impacts detected to date and projected for the future reinforces the case that climate change may reasonably be anticipated to endanger the health and welfare of current and future generations,” the authors concluded.

The report’s release comes after months of speculation over whether the Trump administration will seek to roll back the endangerment finding, which serves as the cornerstone for EPA regulation to control greenhouse gas emissions from a variety of sources.

Last week’s proposed rule change on emissions from new and modified power plants renewed questions about whether the agency was taking aim at the finding.

The researchers based their assessment on peer-reviewed literature, including older versions of the U.N. Intergovernmental Panel on Climate Change and National Climate Assessment. The latest versions of these reports came out too late to be included in detail in their paper.

“To the extent that there would be a challenge of that original endangerment finding, we wanted to make sure there is a place people can go for another reference point on those same types of comments,” said report co-author Sue Tierney, a senior adviser with the Analysis Group and former assistant secretary for policy at the Department of Energy.

She described the report as aimed at deepening public understanding of the environmental changes seen in the last decade. It’s also meant to provide further evidence to political and policy leaders that there is a “compelling record the U.S. economy, communities, and public health and welfare are truly seeing the effects [of climate change] today,” Tierney said.

These effects include risks to the nation’s food supply and coastal communities, and the threat water shortages could pose to the U.S. energy sector.

The authors also point out areas where scientists have gained confidence in their assessments of climate change impacts nationally.

In the past decade, researchers have made great strides in being able to link individual disasters like Superstorm Sandy or Hurricane Katrina to human-caused global warming, and have been better able to track the ecological impact warming has had on marine and wildlife, forest cover, crops, as well as invasive pests and weeds.

Recent research has also more clearly defined social consequences of warming, such as the impact of disasters on mental health, as well as the increased risk of migration and conflict because of changing environmental conditions.

“We know from the very clear scientific evidence that we have to turn the tide on the emissions curve and reduce it dramatically if we are going to keep temperatures within tolerable levels,” said Tierney.

The Trump administration has continued to weaken Obama-era rules aimed at controlling the heat-trapping gases. But it has sidestepped questions of whether it would seek to undo the endangerment finding itself, a move that scholars say is highly legally vulnerable.

Speculation about the fate of the endangerment finding surfaced again last week during EPA’s release of its proposed replacement for the New Source Performance Standards for greenhouse gas emissions from new and modified power plants.

In a press release, EPA noted it was also seeking comment on setting a regulatory threshold of when a source category — like the power sector — either causes or significantly contributes to air pollution.

A top EPA official denied last week that this request signaled the agency was opening up the endangerment finding for consideration (Greenwire, Dec. 7).

“The proposal doesn’t take comment on the endangerment finding, it takes comment on the threshold issue of contribution,” Mandy Gunasekara, assistant administrator for EPA’s Office of Air and Radiation, said during an event at the agency’s Washington, D.C., headquarters.