Methane leaking from yet-to-be explained damage on the Nord Stream 1 and 2 pipelines is likely to be the biggest burst of the potent greenhouse gas on record, raising new fears of the effect on the climate emergency.
The Nord Stream pipeline from Russia to Germany on Thursday was pumping huge volumes of methane into the Baltic Sea as well as the atmosphere – as much as five times more than escaped in the Aliso Canyon disaster – the largest known terrestrial release of methane in US history.
Keep readinglist of 4 items
The leakage could be equivalent to one-third of Denmark’s total annual greenhouse gas emissions, head of the Danish Energy Agency Kristoffer Böttzauw said. Danish emissions in 2020 were about 45 million tonnes of carbon dioxide (CO2).
Russia and the US and European allies have accused each other of deliberately sabotaging the gas pipeline as Moscow’s invasion of Ukraine intensifies.
“Whoever ordered this should be prosecuted for war crimes and go to jail,” said Rob Jackson, a Stanford University climate scientist.
The worst-case scenario is estimated to be 778 million cubic metres of gas leaked, according to the Danish government.
Jackson and David Hastings, a retired chemical oceanographer in Gainesville, Florida, each calculated that would be an equivalent of roughly half a million tonnes of methane. The Aliso Canyon disaster released 90-100,000 tonnes.
Methane is a major contributor to climate change, responsible for a significant share of the climate disruption people are already experiencing. That is because it is 82.5 times more potent than carbon dioxide at absorbing the Sun’s heat and warming the Earth.
Andrew Baxter, a chemical engineer working at the environmental group EDP, had a more conservative estimate than the Danish government, but it was still double the Aliso Canyon disaster.
Just one of the pipelines could release emissions equalling the annual emissions of two million cars, he noted.
“That’s one thing that is consistent with these estimates,” said Baxter. “It’s catastrophic for the climate.”
Methane bubbling at the ocean’s 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 effects of the leaks are still coming into focus, Balcombe said, but are likely to be significant. “It would have a very large environmental and climate impact indeed – even if it released a fraction of this.”
Denmark has said more than half of the gas in the Nord Stream pipelines in the Baltic Sea had leaked into the atmosphere after being damaged by suspected sabotage.
“A clear majority of the gas has already come out of the pipes,” said Böttzauw. “We expect the rest to escape by Sunday.”
The Baltic Sea is one of the most polluted bodies of water on Earth because of industrial chemicals and urban littering.