STOCKHOLM, Sept. 30 (Xinhua) -- The climate impact of the Nord Stream gas leaks is on par with Sweden's annual greenhouse gas emissions, an expert at the Swedish Environmental Protection Agency told Swedish Television (SVT) on Thursday.
The methane leaking from four holes in the twin pipelines under the Baltic Sea could cause significant climate risks, said Mats Bjorsell, an environmental economist at the agency.
Nord Stream, the company operating the pipelines between Russia and Germany, told the Danish Energy Agency that the pipelines contained around 778 million cubic meters of methane when mysterious blasts damaged them on Monday.
Methane is a more powerful greenhouse gas than carbon dioxide, but breaks down faster in the atmosphere. Over a 100-year span, methane causes 28 times greater warming than carbon dioxide, while over a 20-year horizon, it is 84 times more powerful. The calculations of the Swedish Environmental Protection Agency are based on the leaks' climate impact over 20 years, which is more relevant in this case.
The leaks are, therefore, calculated to contribute as much to global warming as 40 million tons of carbon dioxide -- and last year, Sweden's combined emissions were 48 million tons.
Nord Stream realized that there was a problem when the pressure in the pipes suddenly dropped on Monday. Later, Swedish and Danish authorities filmed vast areas where sites of gas streaming out from the holes are visible on the Baltic Sea surface.
Two of the leaks are in Sweden's exclusive economic zone (EEZ) in the Baltic Sea, and two are in Denmark's EEZ.
Since there were several leaks, foul play was suspected, and an analysis of the seismic activity in the area of the leaks revealed a pattern corresponding to explosions on the seabed.
The Swedish Security Service is now investigating the two leaks that occurred in Sweden's EEZ.
At a press conference on Wednesday, Sweden's Prime Minister Magdalena Andersson said that "the detonations must be seen in the light of the security policy situation." However, she added that the Swedish government has so far refrained from speculation. ■