Record methane leak flows from damaged Baltic Sea pipelines

COPENHAGEN, Denmark — Methane leaking from the damaged Nord Stream pipelines is likely to be the biggest burst of the potent greenhouse gas on record, by far.

The Nord Stream pipeline leaks that were pumping huge volumes of methane into the Baltic Sea and atmosphere could discharge as much as five times as much of the potent greenhouse as was released by the Aliso Canyon disaster, the largest known terrestrial release of methane in U.S. history. It is also the equivalent of one third of Denmark’s total annual greenhouse gas emissions, a Danish official warned Wednesday.

“Whoever ordered this should be prosecuted for war crimes and go to jail,” said Rob Jackson, a Stanford University climate scientist. Two scientists looked at the official worst case scenario estimates provided by the Danish government — 778 million cubic meters of gas — for the Associated Press. They calculated that would be an equivalent of roughly half a million metric tons of methane. The Aliso Canyon disaster released 90-100,000 metric tons.

Andrew Baxter, a chemical engineer who formerly worked in the offshore oil and gas industry, and is now at the environmental group EDF thought the Danish estimate was likely too high. He had a more conservative estimate. But it was still more than double the Aliso Canyon disaster.

“That’s one thing that is consistent with these estimates,” he said, “It’s catastrophic for the climate.”

Kristoffer Böttzauw, head of the Danish Energy Agency, said emissions from the three leaks on the underwater Nord Stream 1 and 2 pipelines correspond to approximately 32% of annual Danish carbon dioxide emissions. Danish emissions in 2020 were approximately 45 million tonnes of CO2.

Sabotage was suspected to have caused the leaks, and seismologists said Tuesday that explosions rattled the Baltic Sea before they were discovered. Some European officials and energy experts have said Russia is likely to blame since it directly benefits from higher energy prices and economic anxiety across Europe. But others cautioned against pointing fingers until investigators are able to determine what happened.

Methane seen bubbling at the ocean surface was an indication of “a strong upward flow,” according to Paul Balcombe, a member of the engineering faculty at the department of chemical engineering at Imperial College London.

The loss of pressure in the pipe likely meant a large amount of gas was already lost, he said. The impacts of the gas leak are…