Nord Stream and Climate Change
Since 26 September, mysterious leaks have appeared in the underwater Nord Stream gas pipelines - which run from Russia to Germany - close to the Danish island of Bornholm in the Baltic Sea. Seismologists picked up data that might help to pinpoint the cause of the leaks, and other researchers are trying to work out how much methane - a potent greenhouse gas - will be released as a result. When Andrew Baxter, once an engineer in the oil and gas industry, now the director of energy transition at the Environmental Defense Fund, based in New York City, heard about the leak in Nord Stream 2, he "Switched back into engineering mode" to try to quantify the resulting methane release. Baxter estimated that 115,000 tonnes of methane had probably been released during the initial sudden pressure drop in Nord Stream 2, on the basis of the pipe's dimensions and the water temperature. Per unit mass, methane has a much more potent greenhouse effect than carbon dioxide - particularly in the short term.
The event, although huge, accounts for around 0.14% of the global annual methane emissions from the oil and gas industry, says Mark Davis, chief executive of Capterio, a company in London that tracks gas flares from industry, but which didn't detect the vented gas because it isn't burning. Since the initial pressure drop in Nord Stream 2, leaks have also been reported in the Nord Stream 1 pipeline, which runs alongside it and is also currently not operational. Measuring precisely how much methane has been emitted is going to take time.
The public satellites that environmental observations rely on were not facing the right way at the time, says Itziar Irakulis-Loitxate at Valencia Polytechnic University, Spain, who uses satellite data to measure atmospheric methane levels. That is on top of an inherent challenge in monitoring methane over water: water absorbs most of the sunlight and masks any signal from methane in a spectrometer. The methane spike was detected from the ground by at least one observatory: the Swedish station of the European Integrated Carbon Observation System project at Hyltemossa. In the coming days and weeks, scientists will continue to try to understand how much methane has been released as a result of the leaks.
Source : Nature