On September 28, multiple detonations destroyed three of the four lines of the Nord Stream pipelines. As a result, gas flowed into the Baltic Sea for days and then into the atmosphere. The methane released in particular is a strong greenhouse gas, which is why there were fears of consequences for the climate in addition to the political and economic consequences.
A study by Xiaolong Chen and Tianjun Zhou of the University of the Chinese Academy of Sciences in Beijing in “Advances in Atmospheric Sciences” at least alleviates the latter concerns.
Although it is the largest known release of methane in a single man-made event, the amounts are comparatively small compared to the total global emissions of the gas, the two researchers write.
In total, according to their estimates based on satellite data, 0.22 million tons of methane escaped into the atmosphere, twice as much as the previous leader, a 2015 accident at California’s Aliso Canyon gas field.
However, the value of Chen and Zhou is well below the 0.5 million tons estimated in the first days after the sabotage of the Nord Stream pipelines.
However, the gas leak must be viewed in relation to the total annual emissions of methane: On average, between 2008 and 2017, 70 million tons of the greenhouse gas escaped into the atmosphere every year: from rice paddies, landfills, cow stomachs and during the normal extraction and transport of oil and gas.
As a result, only as much gas escaped from Nord Stream as would otherwise be released from other sources every day. “The additional warming from the emitted methane is so minimal that it would not be felt on a global scale,” says Chen.
Nevertheless, the physicist warns: “If humanity wants to achieve the goals of the Paris climate agreement, damage to infrastructure like this should be avoided.”
Even if methane stays in the atmosphere for a much shorter time than carbon dioxide, its greenhouse gas effect is more than 80 times greater. Reduced emissions are therefore urgently needed to limit global warming to less than two degrees Celsius.
The original of this article “Nord Stream sabotage without major consequences for the climate” comes from Spektrum.de.
