Visoke poletne temperature so povzročile, da so se plini, sicer ujeti v trajno zamrznjena tla severa Sibirije, začeli sproščati. Nenavadne mehurje pod površino travnika so nedavno posneli ruski znanstveniki. Vir: Now the proof: permafrost ‘bubbles’ are leaking methane 200 times above the norm.
The swelling pockets in the permafrost – revealed this week by The Siberian Times – are leaking ‘alarming’ levels of ecologically dangerous gases, according to scientists who have observed this ‘unique’ phenomenon. Some 15 pockets have been found on the Arctic island, around one metre in diameter.
Measurements taken by researchers on expeditions to the island found that after removing grass and soil from the ‘bubbling’ ground, the carbon dioxide (CO2) concentration released was 20 times above the norm, while the methane (CH4) level was 200 times higher.
One account said: ‘As we took off a layer of grass and soil, a fountain of gas erupted.’
An early theory is that warm summer heat has melted the permafrost causing the release of long-frozen gases.
Video images of the phenomenon show how the ground wobbled under the feet of scientists. Other descriptions say the tundra surface – in a permafrost zone some 765 kilometres north of the Arctic Circle – bubbled or trembled.
‘It was like a jelly,’ said one researcher, according to a broadcast by Vesti Yamal. ‘We have not come across anything like this before.’