Nord Stream gas leaks spew methane into atmosphere

Unexplained gas leaks along two undersea pipelines connecting Russia to Germany have sent huge volumes of methanea powerful greenhouse gas in the atmosphere.

Climatologists have described shocking images of gas spitting on the surface of the Baltic Sea this week as a “reckless discharge” of greenhouse gas emissions which, if deliberate, “amounts to an environmental crime”.

Seismologists on Monday reported explosions near the unusual Nord Stream gas leaks, located in international waters but inside the exclusive economic zones of Denmark and Sweden.

The Danish Armed Forces said video footage showed the larger gas leak created a surface disturbance about 1 kilometer (0.62 mile) in diameter, while the smaller leak caused a circle of about 200 meters.

Climatologists acknowledge that it is difficult to precisely quantify the exact size of the emissions and say the leaks are a “little bubble in the ocean” compared to the massive amounts of methane emitted around the world every day.

Nevertheless, environmental activists say the incident shows that the risk of sabotage or accident makes fossil infrastructure a “ticking time bomb”.

For context, the International Energy Agency estimates that annual global methane emissions are around 570 million tonnes.

This means that estimated emissions from gas leaks from the Nord Stream are only a fraction of the global total each year, even though campaigners say the incident is yet another reminder of the risks associated with fossil fuel infrastructure.

Paul Balcombe, honorary lecturer in chemical engineering at Imperial College London, said that even if just one of the two leaking Nord Stream pipes were to release all of its contents, there would probably be twice as much methane as the 2015 Aliso Canyon leak in Californiathe largest known release of methane in US history.

Methane is 84 times more powerful than carbon and does not last as long in the atmosphere before breaking down. This makes it a critical target to rapidly tackle climate change while minimizing other greenhouse gas emissions.

The cause of the Nord Stream gas leaks is not yet known. Many in Europe suspect sabotage, especially as the incident comes amid a bitter energy showdown between Brussels and Moscow. Russia has dismissed claims that it was behind the alleged attack, calling them “stupid”.

Danish Energy Agency said Wednesday that emissions from gas leaks are about a third of the country’s annual greenhouse gas emissions.

Based on the Danish government’s initial estimates, the worst-case scenario would see 778 million standard cubic meters of gas or 14.6 million metric tons of carbon equivalent emissions. By comparison, Danish emissions in 2020 were around 45 million tonnes of carbon equivalent.

Grant Allen, a professor of atmospheric physics at the University of Manchester, said it has been estimated that there could be up to 177 million cubic meters of gas still residual in the Nord Stream 2 pipeline alone.

Allen said that amount is equivalent to the gas used by 124,000 UK homes in a year. “It’s not a small amount of gas and represents a reckless emission of greenhouse gases into the atmosphere,” he added.

Jeffrey Kargel, a senior scientist at the Planetary Research Institute in Tucson, Arizona, described gas leaks in Nord Stream pipelines as a “true travesty” and “an environmental crime if deliberate.”

“The huge water turmoil from the leak, as we’ve seen in the footage, is symbolic of the huge amount of fossil fuel the world is burning,” Kargel said.

“The global climate is changing dramatically, with huge extreme climate impacts every year, decade after decade. It’s climate change so extreme that almost every adult on Earth knows it from experience,” he added. “We can literally feel it on our skin.”