Yerkutinskaya funnel. Picture: Aleksandr Sokolov

New analysis by satellite and helicopter shows gas pipelines run right over swelling tundra which is deeply unstable due to the release of underground methane that had been frozen in permafrost - now thawing - for thousands of years, revealed Russia's leading expert on the new phenomenon, Professor Vasily Bogoyavlensky.

In one recent explosion, permafrost soil was thrown around 1 kilometre from the epicentre of the blast, highlighting the huge force, scientists discovered.

Flames shot into the sky, and a 50 metre-deep crater was formed from the eruption.

The process is seen as caused by the warming Arctic climate and has vast implications for the energy industry in polar regions.



Seyakhinskaya funnel. Picture: Yamal Region

Gas from Yamal is crucial to both Russia and the European energy system, with exports in particular to Poland and Germany.

Some 7,000 pingos - scientific name hydrolaccoliths - have been identified in Yamal, and one estimate is that some 700 of these mounds could be prone to eruptions.

Most are harmless but the difficulty for experts is identifying which are dangerous.

'In a number of areas pingos - we see both from satellite data with own eyes during helicopter inspections - they literally prop up gas pipes,' said the professor.

'I would even use another term - in some places they jack up gas pipes.

'Do you understand? They seem to begin to slightly bend these pipes.'



Yerkutinskaya and Seyakhinskaya funnels. Pictures: Aleksandr Sokolov, Yamal region

Experts say villages and towns are also under threat, but the risk of explosions under gas supply pipelines is clearly acute.

Alexander Mazharov, deputy head of the governor of Yamalo-Nenets autonomous region, said: 'It is cleat that it was not a meteorite, but gas emission.'

The explosion was in an Arctic river, and it was immediately submerged with water.

'We did a good job as we took samples of water, soil and air. Now it is time for laboratories to give us results of analyses,' he said.

Professor Vasily Bogoyavlensky. Picture: Vesti Yamal

Another crater - or funnel - that was found same week is called Yerkutinskaya. This is up to 10 metres in diameter and visible depth is 30 metres.

'Based on satellite data, we have marked 7,000 bulges (pingos) - or even more,' said Bogoyavlensky, deputy director of the Oil and Gas Research Institute, Moscow.

'It doesn't mean that every pingo carries danger but it is still clear that we can draw certain conclusions.

'Locals calls these bulges 'bugunyakhs'. In the West they are called pingos.'



Scientists now believe that Yamal's landscape - pockmarked by round-shaped lakes - was substantially caused by this process over hundreds of years.

This means it was not solely the recent 'global warming' that was responsible but more subtle rhythms of melting every decade with the Arctic Ocean ice cover melting by some 14%.

But it is only in the past three years that the formation of the new craters has been witnessed.

In the case of the most recent explosion - now named Seyakhinskaya - it was witnessed by herders, and reindeer and dogs were seen fleeing in terror - see our previous report here.

Ice inside hydrolaccoliths thaws under the influence of high air temperature, say scientists. Water takes less volume, while the vacant space is filled with a gas mixture, substantially methane.

When the gas pressure inside the dome begins to exceed the pressure of the soil layer on the surface, gas gets out.

Usually this happens as an emission, but in some cases, there is a fierce explosion.

Trembling tundra of the Yamal Peninsula. Video credit Aleksandr Sokolov

Dr Bogoyavlensky believes the explosions are similar to the under-ocean eruptions of methane that caused the so-called Bermuda Triangle.

The Yamal peninsula is now one of the world's key sites for production of natural gas for residential and industrial supplies, notably to Western Europe, for example by Gazprom.

Currently, there are three seismic stations on the Yamal peninsula, in Sabetta, Bovanenkovo and Kharasavey.

Scientists believe at least six permanent stations are required, with three more located in Urengoy, Bely island and Salekhard.

The issue of Yamal tundra explosions is to addressed at the next meeting of the Russian government's state commission on exploration of the Arctic.

Map of the newest Yamal funnels, and pictures of the funnel known as F1, registered in 2014. Pictures: The Siberian Times, Vasily Bogoyavlensky