Whitehouse, Schatz Introduce Bill Advancing Science to Reduce Warming from Ozone, a Potent Air Pollutant and Greenhouse Gas

Washington, D.C. - U.S. Senator Sheldon Whitehouse (D-RI), Ranking Member of the Senate Committee on Environment and Public Works, and Senator Brian Schatz (D-HI) today introduced the Tropospheric Ozone Research Act of 2026 to fund a multi-year scientific research program on the warming effects of tropospheric ozone.

Unlike the beneficial ozone layer that protects the Earth from UV radiation, tropospheric ozone is found near the surface of the earth-and is a major air pollutant and potent greenhouse gas, causing an estimated 500,000 premature deaths and up to 26 percent losses in crop yields globally each year. Tropospheric ozone is also the third-largest driver of climate change after carbon dioxide and methane. Because tropospheric ozone is a short-lived greenhouse gas that lasts only weeks in the atmosphere, cutting tropospheric ozone could significantly reduce temperatures in the near term, alleviating the severity of climate change effects and reducing the risk of crossing climate tipping points.

"For years, I have championed action to slash emissions of methane, a powerful, short-lived climate pollutant. This bill will spur new action on tropospheric ozone, another lesser-known greenhouse gas that is changing our climate," said Whitehouse. "We cannot afford to leave any solutions on the table as the climate crisis grows more severe and threatens to trigger a cascade of economic catastrophes."

"Taking action on super pollutants like tropospheric ozone is critical to the climate fight - and to reducing the harms they cause to our health, farms, forests, and oceans. Our bill will help us better understand how tropospheric ozone drives warming and what we can do about it," said Schatz.

The Tropospheric Ozone Research Act would bring much-needed attention to addressing tropospheric ozone as a climate solution. The Act would fund scientific research to improve understanding of how tropospheric ozone drives global, regional, and localized temperature rise; how tropospheric ozone affects crop losses and forest productivity; and how to maximize temperature reductions by controlling tropospheric ozone.

The legislation is endorsed by the Clean Air Task Force and the Natural Resources Defense Council.

"Tropospheric ozone is a devastating pollutant, responsible for roughly half a million premature deaths a year, billions of dollars in economic damages, and about a quarter degree of present-day warming. Yet it remains largely neglected by climate and clean air policy," said Jonathan Banks, Vice President for Methane at Clean Air Task Force. "The research that could be conducted from this bill would help to close the existing knowledge gap that has contributed to this inaction. By investing in science that improves our understanding of how tropospheric ozone moves through and affects our atmosphere, we can better develop and target the solutions that can drive this pollutant down."

"The Tropospheric Ozone Research Act of 2026 would advance our understanding of ground level ozone as a climate pollutant. While its harms as an air pollutant are well established, the climate impacts of tropospheric ozone remain poorly understood," said Dr. Richie Kaur, Senior Superpollutant Reduction Advocate at the Natural Resources Defense Council. "Tropospheric ozone is a fast-acting driver of warming that damages human health, food systems, and ecosystems, with disproportionate impacts on vulnerable communities burdened by air pollution. At the same time, it represents a great opportunity for near term progress-where stronger science can inform practical policies that deliver rapid public health, ecosystem, and climate benefits."

Full text of the bill is available here, and a one-pager is available here.