"I don't want to sort of criticize Yellowstone National Park, but, I mean, there's hundreds of thousands of vehicles driving through that park every single day," says Hensley. It is somewhat ironic to study carbon cycling using a tracer gas with that much greenhouse forcing.īob Hall, a professor on stream ecology, and a colleague in a 2018 paper on the study of gas exchangeīobby Hensley, who works on NEON for Battelle, told NPR that the climate impact from the scientific use of this gas has to be kept in perspective. "In short, the environmental consequence of a small SF6 application in the park is significant," noted White, who recommended that NEON immediately substitute an alternative gas, such as argon, even though NEON staffers thought making this switch would be problematic because of things like lab contracting constraints. Over the 30-year lifetime of the project, White calculated, that meant the use of SF6 for research in Yellowstone National Park alone would be equivalent to burning over 1,139,000 pounds of coal. NEON's protocols called for it to annually release around 3.3 pounds of sulfur hexafluoride, or SF6, in Yellowstone National Park, hydrologist Erin White pointed out in a November, 2020 email to another National Park Service official. That's the same year when a scientist at Yellowstone National Park started to question why NEON was releasing sulfur hexafluoride at Blacktail Deer Creek, according to documents obtained through a public records request by Public Employees for Environmental Responsibility, a group that supports workers within the government who are concerned about activities that can harm the environment. The planning for this half-billion-dollar ecological project, and the construction of its monitoring instruments, took around twenty years. NEON workers sample fish in 2019 at Lower Hop Brook in Massachusetts, one of the streams being monitored as part of this long-term ecological study. One reason that's of interest is that, although inland waterways cover up only a small fraction of the Earth's surface, researchers believe these running waters could be an important source of greenhouse gasses, as rainfall can carry carbon from the ground into turbulent streams that later release it into the atmosphere.Įcologists have always known that sulfur hexafluoride was itself a potent greenhouse gas, "but we always said, 'Well, we're using just a tiny amount of it," says Bob Hall, a professor of stream ecology at the University of Montana. That's not good enough for one watchdog group, which is calling for an immediate halt to the release of this gas on public lands.įor decades, ecologists have sometimes burbled small amounts of sulfur hexafluoride into streams and rivers, in order to study how quickly gasses can move from the water into the air. The National Science Foundation (NSF), which funds this large ecology study, told NPR that it supports an evaluation that's now underway to see whether phasing out the use of this gas would affect the quality of the information that's being gathered. But it comes at a time when all kinds of researchers are thinking about the climate effects of past practices, with some saying that scientists who understand the urgency of the climate crisis have a special obligation to set an example to the public by reducing the greenhouse gas emissions of their own work. This kerfuffle has so far played out quietly within government agencies.
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. 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. It's 22,800 times more effective at trapping heat than carbon dioxide, and lasts in the atmosphere for thousands of years. The gas, sulfur hexafluoride, is "the most potent greenhouse gas known to date," according to the Environmental Protection Agency. Blacktail Deer Creek in Yellowstone National Park, seen here in a 2019 photo from the ecological study known as NEON, is one site where researchers have bubbled sulfur hexafluoride into the water.Ī 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.