Leaks in two natural gas pipelines under the Baltic Sea have sparked concern over the potential impact of escaping gas on the climate.
The pipelines that run underwater from Russia to Germany carry natural gas – the main component of which is methane, a powerful contributor to global heating.
Leaks were discovered in the pipelines on Tuesday after seismologists reported explosions that rattled the Baltic Sea. The European Union on Wednesday said all available information indicates that they were the result of a “deliberate act,” although it did not assign blame.
As the leaks sparked alarm among the diplomatic community, so too did it prompt concern from environmentalists. Methane is a very powerful greenhouse gas – 30 times stronger than carbon dioxide over 100 years and 80 times stronger over 20 years. Although it stays in the atmosphere for only around a decade compared to carbon dioxide which can stay in the atmosphere for anywhere between 300 and 1,000 years.
How bad the climate and environmental impact turns out to be depends partly on how much gas is in the pipes and how much is escaping, much of which remains unclear. Neither pipeline was in operation but both contained gas, according to Reuters.
What is clear is that any methane leak will have some impact.
“Methane leaked rather than burnt is around 30 times worse for climate,” Piers Forster, director of the Priestley International Centre for Climate at the University of Leeds, told the Science Media Centre. “The leak will have a strong immediate warming effect and cause poor air quality as well.”
Grant Allen, a professor of atmospheric physics at the University of Manchester, said because the pipelines were not pumping and were just pressurised once the gas had escaped the leak should stop. Some of the methane emitted will be oxidised into carbon dioxide as it rises, he said, but due to the violent rush out of the pipe most of the gas would reach the sea surface as methane.
“It has been estimated that there may be up to 177 million cubic metres of natural gas still residual in Nordstream 2 alone,” he said, adding that this was equivalent to the natural gas used by 124,000 UK homes in a year.
“This is not a small amount of gas, and represents a reckless emission of greenhouse gases into the atmosphere.”
Bloomberg reported that Germany had estimated that about 300,000 metric tons of methane had entered the atmosphere due to the leaks. The Independent has not confirmed the report.
Greenpeace put it this way in a Tweet on Wednesday: “We don’t know exactly how much gas was in the pipelines, how much leaked, and how much is absorbed by the water instead of the air. But what’s certain is that this is terrible news for the climate, and that Europe’s addiction to gas must end.”
Professor Forster said compared to the daily leaks in the poorly maintained gas network around the world this leak will be small. Every day, around 10 per cent of our global gas supply is leaked into the atmosphere, he said.
“This is both wasteful and bad for climate,” he said. “Getting on top of leaking gas pipes generally can really reduce warming rates this decade.”
Many scientists and activists said renewable energy infrastructure was not only cheaper but more secure than fossil fuel infrastructure. Governments should do everything possible to move to renewables and cut energy waste, rather than look for more gas supplies, said Greenpeace.
“More gas = more leaks,” it added.