As the Arctic warms, bubbling springs emerging from beneath shrinking glaciers could provide an underappreciated source of the potent greenhouse gas methane – according to new research presented today at EGU23. Research led by researchers from the University of Cambridge and the University Centre in Svalbard, Norway, has identified large amounts of methane escaping from springs exposed by retreating glaciers across Svalbard in the high Arctic, the fastest-warming region on Earth. Gabby Kleber, lead author of the research from Cambridge’s Department of Earth Sciences, has spent much of the past three years monitoring the chemistry of water in more than a hundred springs in Svalbard – identifying highly concentrated methane that can quickly escape into the air when exposed.

The research found that methane emissions from the springs reached at least two kilotonnes per year – roughly equivalent to the methane released by two million cows over the same time frame. “We found that these springs could be a significant source of methane emissions – one that has been missing from the picture until now, and will become more significant if global warming continues unchecked,” Kleber said. Methane gas is the third most important greenhouse gas in the atmosphere, after water vapor and carbon dioxide. Although methane is present in lower concentrations than carbon dioxide, it is about 28-34 times more potent in terms of its ability to warm the atmosphere. Most of the methane on Earth is produced by microorganisms that convert organic matter into methane in oxygen-deficient environments such as natural wetlands. However, a significant portion of the global methane budget comes from human activities; including agriculture, waste disposal and the burning of fossil fuels. Melting ice and permafrost across the Arctic is another source of methane that scientists are increasingly concerned about. That's because the melting could trigger a sudden release of trapped methane—rapidly warming our planet and adding to human-caused global warming. The extent and pace of this release are difficult for scientists to determine, which adds uncertainty to calculating the global methane budget and how it might change in the future. (Dr C.M. Martin-Jones)