A new study out of Johns Hopkins University has found that as much as 17% of the global emissions of the greenhouse gas sulfuryl fluoride is emitted by the United States, with the majority of these emissions being traced to just a few counties in California.
This surprised researchers since California has a reputation for being aggressive in cutting its greenhouse gas emissions in recent years.
“When we finally mapped it out, the results were puzzling because the emissions were all coming from one place,” said co-author Scot Miller, an assistant professor of environmental health and engineering at Johns Hopkins. “Other greenhouse gases like carbon dioxide and methane are found everywhere across the U.S. On our sulfuryl fluoride map, only California lit up like a Christmas tree.”
The study lead author Dylan Gaeta, and co-author Miller researched more than 15,000 air samples that were collected between 2015 and 2019 by the NOAA Global Monitoring Laboratory.
Through analysis, they were able to determine that between 60% and 85% of sulfuryl fluoride emissions generated in the United States come from the state of California. These emissions reportedly came from counties like Los Angeles, Orange, and San Diego.
The study was concerned with a rise in sulfuryl fluoride emissions because they stick around for a long time in the atmosphere.
“Sulfuryl fluoride (SO2F2) is a synthetic pesticide and a potent greenhouse gas that is accumulating in the global atmosphere. Rising emissions are a concern since SO2F2 has a relatively long atmospheric lifetime and a high global warming potential,” the study said.
Geata was encouraged by the study’s results, which will help climate researchers get a more concrete idea of where SO2F2 emissions are actually coming from so that California can reach its goal of achieving net zero emissions by 2045.
“We can now show not only where but also how and why this gas is being emitted, In order to get to net-zero emissions, we need a complete inventory of what greenhouse gases are out there,” Gaeta said.
The main source of SO2F2 emissions in California is thought to be the pesticides used in the state to keep insect, rodent, and other pest populations down. The study team was able to determine that 85% of the SO2F2 emissions come from this source.
California has been leading the country on ambitious goals and efforts to reduce greenhouse gas emissions, which climate scientists think contribute to rising average global temperatures.
In 2022, California released the world’s first plan to achieve net-zero emissions by 2045. By 2030, the state hopes to have a 48% reduction in greenhouse gases, which would put it well below levels in previous decades.
However, this study along with a March CalMatters report has cast doubt on this ambitious goal. CalMatters reported that California is no longer on track to meet the 2030 goal, saying it would need to “triple its rate of reducing greenhouse greenhouse gases.”
The state had made progress on this goal during the pandemic, but when businesses reopened and people restarted the economy, much of that progress was lost.
“The fact that they need to increase the speed of reduction at about three times faster than they’re actually doing — that does not bode well,” said Stafford Nichols, a researcher at Beacon Economics, a Los Angeles-based economics research firm, and a co-author of the annual California Green Innovation Index.
