“Why is a destructive methane cloud flying over Europe”, “Why is a harmful methane cloud flying over Europe and heading straight for Italy? “. After the massive leaks found after explosions in the Nord Stream 1 and Nord Stream 2 gas pipelines in the Baltic Sea, several media reported worryingly about the passage of this gas through European territory and raised the question of the possible impact on France. On Maps shared on Twitter actually show models of the extent of the CH4 plume (the ‘chemical’ name of methane) into Brittany, and a monitoring station installed at Roc’h Trédudon even recorded an increase in methane concentrations in the air.
Aha – a little bonus since the cloud is slowly moving east??
The new CH4 data from Ro’ch Trebudon in Brittany, a new station of the French greenhouse gas monitoring network. It’s in yellow below pic.twitter.com/vUmeZH5f0Z
— Philippe.ciais (@ciais_philippe) 09/30/2022
“It’s not the Chernobyl episode!” »
Contacted Thomas Lauvaux, CNRS researcher at the Laboratory of Climate and Environmental Sciences in Gif-sur-Yvette (91), immediately assures: “There are no dangerous clouds moving over our heads. These emissions pose no hazard in the short term. The amounts are so small (one to two molecules for every 10,000 molecules of air) that there is no risk of explosion or health hazards.” “It’s not the Chernobyl aftermath!” There is no toxicity,” agrees Michel Ramonet, CNRS researcher and coordinator of the European Icos network of greenhouse gas monitoring stations in France.
The Landivisiau-born scientist tells the story of the events that followed the explosions on the gas lines: “A few hours later, three Nordic stations in southern Sweden and Norway registered the strongest signal with never-before-seen concentrations of methane at those stations, knowing that it has been since ten years,” he begins.
“Our colleagues then ran an atmospheric transport model to get an idea of the cloud’s trajectory. There we could see that it circulated first to Norway and Sweden and then to Denmark and the United Kingdom. Two or three days later, when entering France, we went back down via Brittany in a kind of loop.”
A leak estimated at 200,000 tons
Without a local danger for Europe, the release of these 200,000 tons of methane into the air will not remain without long-term consequences for the entire globe. “That corresponds to one year of methane emissions in Brittany,” compares Michel Ramonet. This gas has a greenhouse effect capacity 10 times greater than that of carbon dioxide (CO2): “The released methane is added to all molecules in the atmosphere, further amplifying the greenhouse effect at the planetary scale,” explains Thomas Lauvaux, co-author of a study published in Science in February Study Finding Hundreds of Large Methane Leaks Caused by Oil & Gas Production. Significant as it is, the amount being lost in the Baltic Sea this week actually accounts for just 1% of annual methane emissions associated with the hydrocarbon sector in Russia. Another possible comparison: “That corresponds to the greenhouse gas emissions of one million cars in one year. If such an event were to happen again, climate policy would become anecdotal,” Thomas Lauvaux fears.
On Monday, the bubbling over Nord Stream 1 caused by gas leaks stopped, but not over Nord Stream 2. Russia accuses the USA of being the cause of the explosions.