Rapidly retreating Arctic glaciers are triggering the release of ancient methane. Here's why scientists are worried.

• Groundwater springs belching methane have appeared close to Svalbard's retreating glaciers.
• Scientists think the glaciers acted as plugs to contain methane reserves.

Hundreds of groundwater springs have appeared in the Arctic, and scientists are worried they are belching vast amounts of ancient methane into the atmosphere.

The springs were exposed by retreating glaciers in Svalbard, a Norwegian archipelago in the Arctic Ocean.

Researchers at the University of Cambridge believe the methane is millions of years old, seeping out from a large reserve of underground gas.

This suggests a lot of greenhouse gas could still be released into the atmosphere — something that hasn't been accounted for in existing climate models.

The methane seems to come from ancient rock

This isn't the first time scientists have found water spewing methane. In fact, there are lakes in Alaska you can set on fire. These are called thermokarsts and they appear when permafrost thaws.

In the case of thermokarsts, however, the methane comes from microbes that grow in the meltwater. Scientists think the methane in the Svalbard springs comes from somewhere else.

Researchers retrieved water from 123 springs in Svalbard between 2021 and 2022. In 122 of these, they found superconcentrated methane.

Their analysis suggests this methane comes from reserves of gas spawning from shale rock underlying the glaciers. The findings were published in Nature Geoscience on Thursday.

"We have identified this previously unknown methane source up here in the Arctic," Gabrielle Kleber, an Earth scientist at the University of Cambridge and lead author on the study, told Insider.

There's so much gas in the springs, the scientists were able to set them on fire just with a match:

"It's shocking, it's scary," said Kleber.

"We drill into these icings and sometimes we just immediately get a lot of pressurized gas blowing out, very loud, it's a bit ominous," she said.

A lot of methane could seep out if the Arctic continues to melt

The glaciers had been acting as plugs to trap the methane in ancient rock,. As their weight lifted from the bedrock, methane trapped deep in the ground made its way to the surface.

"We have a very large reservoir of organic carbon that actually is double the size of the current amount of carbon in the atmosphere trapped beneath glaciers and permafrost in the Arctic," said Kleber.

"If these groundwater springs are tapping into that reservoir, they kind of have an infinite supply of methane behind them. If they can grow in number, grow in size, they can just keep supplying more and more methane to the atmosphere," said Kleber.

The researchers estimate springs across the archipelago alone could represent about 2,000 tonnes of methane emissions a year.

As of today, that's a drop in the bucket of global emissions. The global agriculture industry alone released about 141 megatonnes of methane in 2021, according to the International Energy Agency.

The problem is Svalbard may only be the canary in the coal mine.

"There are large regions in the Arctic that we suspect are seeing the same phenomenon. So if we extrapolate or expand this across the Arctic, the emissions could be considerable," said Kleber.

Methane is a potent greenhouse gas and contributes to a feedback loop

Methane emissions have been a hot-button issue in the fight against the climate crisis. That's because methane is a greenhouse gas, meaning it keeps heat radiating from the ground trapped in the atmosphere instead of letting the Earth cool down.

It doesn't get stuck in the atmosphere as long as carbon dioxide (CO2). But even if it doesn't accumulate for as long, it can cause a lot of damage because it's about 30 times more effective at trapping heat than CO2.

"Reducing methane emissions is an important tool we can use right now to lessen the impacts of climate change in the near term, and rapidly reduce the rate of warming," Rick Spinrad, the head of NOAA, previously said.

If confirmed, this could change climate models

It's difficult to know how bad this problem could be because the research is very new.

Climate models are struggling to keep up with the rate of melting of the Arctic, which is surpassing most predictions. Kleber suspects these methane emissions are only one of several "invisible feedback loops that we're just not aware of."

"This feedback loop of melting glaciers, releasing methane could very likely be a contributor to that discrepancy in our, our large uncertainty in methane emissions, particularly in the Arctic," said Kleber

More research is needed to confirm the origin of the methane and understand the scale of the problem across the Arctic, she said,

"Ultimately we need to be addressing our anthropogenic emissions so that we can prevent these kinds of emissions from growing any further to the point where they are a global impact to our methane budget or our methane emissions," said Kleber.