Nord Stream rupture may be largest methane gas leak on record

UN researchers say devastating plume of gas is a major setback to emissions targets

Leaks in the Nord Stream pipeline have led to what is likely the largest release of methane gas recorded, a UN environmental body has said.

A huge plume of highly concentrated methane was detected in an analysis this week of satellite imagery by researchers associated with the UNEP's International Methane Emissions Observatory. Methane is a greenhouse gas far more potent but shorter-lived than carbon dioxide.

“This is really bad, most likely the largest emission event ever detected," Manfredi Caltagirone, head of the observatory, said. “This is not helpful in a moment when we absolutely need to reduce emissions.”

Researchers at GHGSat, which uses satellites to monitor methane emissions, estimated the leak rate from one of four rupture points was 22,920 kilograms per hour. That is equivalent to burning about 630,000 pounds of coal every hour, GHGSat said.

"This rate is very high, especially considering it's four days following the initial breach," the company said.

Mystery continues to surround the causes of damage to the crucial trans-Baltic pipeline but Western countries have squarely blamed Russia for incident. Moscow countered with its own allegations, claiming that 'Anglo-Saxon' saboteurs were to blame.

Mr Caltagirone said, whatever the cause, the damage to the pipeline posed a problem beyond energy security. “This is the most wasteful way to generate emissions,” he said.

The total amount of methane leaking from the Gazprom-led pipeline system may be higher than from a major leak that occurred in December from offshore oil and gas fields in Mexican waters of the Gulf of Mexico, which spilled around 100 metric tonnes of methane per hour, Caltagirone said.

Improved satellite technology has rapidly enhanced the ability of scientists to find and analyse greenhouse gas emissions in recent years, something governments hope will help companies to detect and prevent methane emissions.

UK Prime Minister Liz Truss said the leaks were “clearly an act of sabotage” as she met for talks with her Danish counterpart Mette Frederiksen in Downing Street on Saturday.

Speaking outside No 10, Ms Frederiksen said: “One of the reasons why I’m here today is because of the situation in the Baltic Sea, with Nord Stream 1 and 2.

“I was able to give some details about what has happened in Denmark, or just outside Denmark.

“Of course, it has been very important for me to underline that the Danish authorities have said that this is not an accident.

“This is sabotage and it is critical infrastructure. So of course, this is a very serious situation.”

On Friday, a Swedish-Danish report into the leaks said the blasts that caused several leaks on the crucial pipeline were equal to several hundred kilograms of TNT. The country said it did not believe anyone other than a state could have caused the undersea blasts.

It came as gas started flowing to Poland through the new Baltic Pipe pipeline from Norway via Denmark and the Baltic Sea on Saturday morning, Polish gas pipeline operator Gaz-System said.

The pipeline, with an annual capacity of 10 billion cubic metres, was officially inaugurated on Tuesday, a day after leaks were detected in the subsea Nord Stream gas pipelines linking Russia to Europe.

Russia cut gas supplies to Poland in April when it refused to pay in roubles.