Svalbard shows that accumulations of natural gas trapped at permafrost are common.
Arctic permafrost, melting due to rising temperatures, holds a hidden danger: massive stores of methane, a potent greenhouse gas. Scientists call it the "methane monster," unsure of its full impact but fearing its release. Exploring Svalbard,a Norwegian archipelago in the Arctic Ocean, they discovered deep methane deposits closer to the surface than expected, raising concerns about a potential rapid release and its global consequences. The Arctic's frozen ground holds a ticking time bomb, and scientists are scrambling to understand its threat.
As per a release, because Svalbard's geological and glacial history is very similar to the rest of the Arctic region, these migrating deposits of methane are likely to be present elsewhere in the Arctic.
"Methane is a potent greenhouse gas," said Dr. Thomas Birchall of the University Center in Svalbard, lead author of the study in Frontiers in Earth Science. "At present, the leakage from below permafrost is very low, but factors such as glacial retreat and permafrost thawing may 'lift the lid' on this in the future."
The researchers stressed that the occurrence of gas accumulations was more widespread than anticipated. Out of the 18 hydrocarbon exploration wells conducted in Svalbard, eight revealed signs of permafrost, and half of these encountered gas accumulations.
"All the wells that encountered gas accumulations did so by coincidence-by contrast, hydrocarbon exploration wells that specifically target accumulations in more typical settings had a success rate far below 50%," said Birchall.
"These things seem to be common. One anecdotal example is from a wellbore that was drilled recently near the airport in Longyearbyen. The drillers heard a bubbling sound coming from the well, so we decided to have a look, armed with rudimentary alarms designed for detecting explosive levels of methane-which were immediately triggered when we held them over the wellbore."