Theoretically, in large quantities methane existing in the underground deposits of the Arctic sealed under a frozen layer permafrost (frozen soil) as well as under glaciers, providing their insulation and preventing this dangerous greenhouse gas from escaping into the atmosphere. HE The heating power of methane is much higher than that of CO2. and it’s been there for decades, albeit to a lesser extent, in the air.
However, at sufficiently high pressures and temperatures, methane found under permafrost and glaciers can be retained as a solid gas hydrate. These pressure and temperature conditions will change with climate warming and glacier retreat, potentially leading to the breakdown of gas hydrates and releasing subterranean methane into the polar atmosphere.
Researchers from the University of Cambridge in the UK and the Svalbard University Center in Norway large reserves of methane gas emanating directly from the ‘prison’ by melting glaciers.
The research, newly published in Nature Geoscience, suggests that these methane emissions will likely increase as Arctic glaciers melt. This and other methane emissions produced by melting ice and the frozen ground at the North Pole, exacerbates global warming.
“These sources are an important and potentially growing source of methane emissions and a resource that is missing from our global estimates of this gas. So far,” said Gabrielle Kleber, lead author of the study, of the Cambridge Department of Earth Sciences.
Kleber spent nearly three years monitoring the water chemistry of more than a hundred springs in Svalbard., where air temperatures are rising twice as fast as the Arctic average. “As this is happening, we are in a position to preview the potential methane release that could occur on a larger scale in this region.”
An unknown methane emission route
Professor Andrew Hodson, co-author of the study from the University Center of Svalbard, said: “Living in Svalbard puts you at the forefront of Arctic climate change. I can’t think of anything more vulgar than your vision. Methane removal near a receding glacier”.
“Although attention is often focused on permafrost, this new finding tells us it’s there. Other routes for methane emissions This could be even more important in the global methane budget,” added co-author of the study, Professor Alexandra Turchyn, also from the Department of Earth Sciences, Cambridge.
Hodson added: “Until this study was finished, we did not understand the source of methane and its escape routes, as we were looking at completely different regions of the Arctic where there were no glaciers.”
The methane release springs they describe are a gallery system, most of which is hidden under the glacier, network This takes advantage of large groundwater reserves in the underlying sediments and surrounding bedrock.
2,000 tons of methane a year in Svalbard alone
As glaciers melt and retreat, springs appear where this groundwater network reaches the surface. Experts discovered that Methane emissions in Svalbard can exceed 2,000 tons a year, this equates to about 10% of Norway’s annual methane emissions from the oil and gas energy industry.
Kleber warned that this source of methane will become more important as more resources become available: “If global warming continues unchecked, then methane emissions will likely be higher”. These sources were not always easy to recognize, so Kleber trained his eye to select them from satellite images.
In Svalbard, he zoomed in on the land areas created by the retreat of 78 glaciers, looking for blue dots that indicate where groundwater has seeped and frozen to the surface. He then traveled by snowmobile to each of these areas to take groundwater samples.
When Kleber and his team analyzed the chemistry of water He found that all the sites examined, which fed these sources, contained large concentrations of dissolved methane, that is, When spring water reaches the surface, there is excess methane that can escape into the atmosphere.
researchers they also identified localized methane emission pointswas closely related to the type of rock from which the groundwater came out. Some rocks, such as shale and coal, contain natural gases, including methane, which is produced by the breakdown of organic matter when rocks are formed.
This methane can pass up through cracks in the surface and into groundwater. “We’re starting to understand the complexity of glacier melt in Svalbard. It seems likely that there are more consequences like this that we haven’t figured out yet,” Kleber said.
”The amount by which we measure the amount of methane escaping from sources will likely increase. That’s the total volume of trapped gas lying under the glaciers waiting to come out. This means we urgently need to identify the risk of a spike in methane seepage because glaciers will only continue to retreat,” Hodson concluded.
Reference work: https://www.nature.com/articles/s41561-023-01210-6
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