Melting Arctic glaciers are a source of methane emissions: What a new study says

The findings were mentioned in a study, ‘Proglacial methane emissions driven by meltwater and groundwater flushing in a high-Arctic glacial catchment’, which was published in the journal Biogeosciences earlier this month.

What did the study find?

For their study, the researchers analysed a small valley glacier in central Svalbard, called Vallåkrabreen. They look at methane levels in groundwater springs and the melt river draining from the glacier.

“Their results were striking. Methane concentrations in the melt river were found to be up to 800 times higher than the atmospheric equilibrium level,” the Science Daily report said.

Notably, the methane that was being released was not produced by microbial activity beneath the ice. Rather it came from thermogenic sources — methane that had been trapped in the region’s ancient geological formations for millions of years.

Gabrielle Kleber, researcher at UiT The Arctic University of Norway and co-author of the study, told Science Daily, “Glaciers act like giant lids, trapping methane underground. But as they melt, water percolates and flushes through cracks in the bedrock, transporting the gas to the surface. You can think of it as a natural fracking process, or as we have called it: glacial fracking.”

Why is methane a big problem?

Methane is one of the main drivers of climate change, responsible for 30 per cent of the warming since preindustrial times, second only to carbon dioxide. Over 20 years, methane is 80 times more potent at warming than carbon dioxide, according to a report by the United Nations Environment Programme.

It is also the primary contributor to the formation of ground-level ozone, a colourless and highly irritating gas that forms just above the Earth’s surface. According to a 2022 report, exposure to ground-level ozone could be contributing to 1 million premature deaths every year.

Several studies have shown that in recent years, the amount of methane in the atmosphere has dramatically shot up. In 2022, the US National Oceanic and Atmospheric Administration (NOAA) said that the atmospheric levels of methane jumped 17 parts per billion in 2021, beating the previous record set in 2020.

“While carbon dioxide remains in the atmosphere for much longer than methane, methane is roughly 25 times more powerful at trapping heat in the atmosphere, and has an important short-term influence on the rate of climate change”, the agency said.