"A massive ecological study that's happening across the United States, and which is designed to track the impact of long-term changes like a warming climate, is deliberately releasing a highly potent and persistent greenhouse gas in national parks and forests.

The gas, sulfur hexafluoride, is "the most potent greenhouse gas known to date," according to the Environmental Protection Agency. It's 22,800 times more effective at trapping heat than carbon dioxide, and lasts in the atmosphere for thousands of years.

So far, this ecology study has released around 108 pounds of the gas, which has about the same impact as burning more than a million pounds of coal.

That may not seem like a big deal in the grand scheme of global emissions, but government scientists working at federal parks and forests have objected to using this gas on public lands — especially since this major study is designed to go on for 30 years and alternative gasses are available."

Nell Greenfieldboyce reports for NPR August 15, 2022. [2]