(Bloomberg) -- Airborne methane levels rose markedly last year, according to a preliminary estimate published today by the U.S. National Oceanic and Atmospheric Administration. The results show a dramatic leap in concentration of the second most-powerful greenhouse gas, which is emitted from both industrial and natural sources.

“Last year’s jump in methane is one of the biggest we’ve seen over the past twenty years,” said Rob Jackson, professor of Earth system science at Stanford University and chair of the Global Carbon Project. “It’s too early to say why, but increases from both agriculture and natural gas use are likely. Natural gas consumption surged more than two percent last year.”

Methane levels have accelerated twice in the last 15 years, first in 2007 and again in 2014. Scientists have yet to pinpoint the exact cause (or causes). Virtually every contributor to the global methane problem may play a role, from the oil-and-gas industry to human agriculture to wetlands changing with the climate.

Methane is about 25 times more powerful a heat-trapping gas than its nearest competitor—carbon dioxide—when extrapolated over the course of a century.

Oil and gas producers have long been criticized for tolerating methane leaks at gas well sites, pipelines, and compressor stations. A June 2018 study by the Environmental Defense Fund estimated that these leaks are equivalent to $2 billion in losses for the industry. The EDF did not take into account the gas producers purposely burn at at well sites to keep even more crude flowing, a practice that enrages environmental activists.

Some of the world's biggest oil and gas producers have recently become more vocal about addressing leaks and setting climate goals. Last month Bernard Looney, the recently appointed chief executive officer of BP PLC, pledged to cut carbon dioxide emissions from the company's own operations and production by 2050, the boldest plan yet from the fossil fuel industry.

Energy use and economic activity are tightly connected, which means that the halt in global production from the Covid-19 pandemic is likely to cause the highest drop-off in emissions seen in decades.

The recent collapse in crude prices may also lessen the need to flare gas, which was already on the decline in the Permian over the first three months of 2020, according to data released Monday by Rystad Energy AS.

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