There's So Much Methane in This Arctic Lake That You Can Light the Air on Fire

Via livescience.com by Brandon Specktor

All day long, the surface of Esieh Lake in northern Alaska shudders with indigestion. This Arctic lake never fully freezes. Stand next to it, and you'll hear it hiss. Watch it, and you'll see it boil with ancient, bubbling gas. Light a fire over it, and the lake will fart a tower of flame higher than your head.

That's exactly what Katey Walter Anthony, an aquatic ecosystem ecologist at the University of Alaska Fairbanks, did in a popular YouTube video from 2010. Walter Anthony has been studying Esieh Lake for the better part of a decade (she also named it). Now, according to a profile written by Chris Mooney for The Washington Post, sheknows the causeof the lake's odd behavior. The culprit is a constant seep of the greenhouse gas methane —a lot of methane — spilling out of an ancient reservoir of permafrost (or permanently frozen ground) deep below the tundra.


Thanks to rising global temperatures, that permafrost is thawing, Walter Anthony said, and it's carving a hole through the bottom of the lake. While most of Esieh Lake has an average depth of about 3 feet (1 meter), the sections where the biggest methane bubbles are seeping out plunge down to up to 50 feet (15 m).

From these holes in the bottom of the lake, huge amounts of methane come gushing out — more than 2 tons of gas every day, according to one of Walter Anthony's colleagues — an amount that's equivalent to the emissions of about 6,000 dairy cows (cow farts are one of the world's largest methane sources).

Thawing Arctic permafrost is a huge concern for climate scientists. Within these frozen sheets of past plant life, thousands of years of greenhouse gases are thought to lie trapped. As global temperatures rise and permafrost begins to melt, that gas is slowly released into the atmosphere. Researchers' greatest fear is that this Arctic off-gassing will start a feedback loop: The more greenhouse gases released by permafrost today, the higher temperatures will climb and the more gases will be released tomorrow.

"These lakes speed up permafrost thaw," Walter Anthony told The Washington Post. "It’s an acceleration."

While many climate models focus on the effects of carbon dioxide being released from thawing permafrost, methane emissions in lakes like Esieh have been largely overlooked until very recently. In a study of several underground Arctic lakes published Aug. 15 in the journal Nature Communications, Walter Anthony and her colleagues estimated that methane-seeping lakes could double previous estimates of permafrost-caused warming.

According to a 2014 study led by the National Snow and Ice Data Center in Colorado, carbon released from thawing permafrost could increase global warming by about 8 percent, contributing about 0.6 degrees Fahrenheit (0.3 degrees Celsius) to the predicted increase of 7 to 9 degrees F (4 to 5 degrees C) by the year 2100. If Arctic methane emissions are as serious as Walter Anthony and her colleagues predict, that increase in temperature could come much, much sooner.

Originally published on Live Science.

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