Beneath The Ice: Thawing Arctic Permafrost Releases Massive Stores of Methane
By James Currie
I remember the soft feeling as my boots slowly sank deeper into grey mud. Ohio’s summer had reached its humid zenith, and the sun beat down mercilessly in the dripping air. Eight-foot cattail leaves rustled occasionally over my head, but no breeze disturbed the surface of the marsh that I was standing in. Red-winged blackbirds trilled in the trees. Dragonflies darted overhead. I wiped my forehead, checked my watch, and then bent over a plastic chamber to collect an air sample. The reason I was out in the middle of nowhere collecting air samples? I was looking for marsh gas. Specifically, methane.
I have a strange relationship with methane. It kickstarted my work experience, although before I started working on it I would have had no idea what it was. To be completely honest, I should tell you that I am not an expert by any means. My knowledge of methane, and its impacts, is sourced from experts, and I have included citations in this article (which I highly encourage anyone interested to check out). So, with that out of the way, let’s dive in.
Methane is a gas that most of us have experienced at some point in our daily lives. It’s highly flammable, and is used throughout the world as one of the primary components of natural gas. Although methane is found in relatively small quantities in the atmosphere, it can have a significant impact on the earth’s climate. Methane is a highly efficient greenhouse gas, able to contain approximately thirty five times the heat that carbon dioxide, the world’s most common greenhouse gas, is able to store. Every particle of methane emitted into the atmosphere is roughly equivalent to thirty five particles of CO2. For example, if a car’s exhaust were composed of methane rather than carbon dioxide, the car would have approximately the same global warming potential (GWP) as thirty five ordinary cars. Methane is emitted from a wide variety of sources: it naturally rises from swamps and freshwater marshes, it emerges from stores beneath the ground, and of course, it is a significant byproduct of human activities. However, I’ve learned about another potential methane source – one that I didn’t think much about until the recent fires in the Arctic: arctic soils contain vast stores of this volatile gas.
The Arctic is debatably one of the most imperiled ecosystems on earth. The lands north of the Arctic Circle (size of the arctic) are facing a plethora of challenges from climate change – polar bears are being forced from their native lands due to sea ice loss and food shortages, the forests are steadily pushing north as the tundra recedes, arctic wildfires are rising in frequency, and the permafrost, the perpetually frozen ground locked in the Arctic, is warming up. The thawing of permafrost as a byproduct of climate change is potentially one of the most significant risks associated with warming the arctic, because arctic soils store vast quantities of methane.
Although scientists can tell with some accuracy how much carbon is locked in the Arctic, it is far more difficult to determine how much of that carbon may be released as methane resulting from climate-induced warming. There are a variety of models that depict possible carbon release numbers ranging from 37-174 billion tons being emitted from formerly frozen arctic soils by the year 2100. These models differ depending on a number of variables. Although we are already committed to significant long-term warming in the Arctic, the extent of that predicted warming varies from model to model, and depends heavily on our actions today to either prevent or exacerbate climate change. Even more threatening is the positive feedback loop that methane release can generate, where methane release causes higher temperatures, which in turn leads to greater thawing and more methane being released. This self-amplifying cycle is part of what has led other news organizations to brand arctic permafrost as a ‘climate time bomb.’ Even more interestingly, these numbers only account for terrestrial ecosystems. There is more methane stored beneath arctic sea ice, though scientists still have very little idea of how much is there.
Another interesting side effect of climate change in the Arctic is its increasing fire risk. In 2019, a significant amount of public attention was diverted to the massive fires in the Amazon. But there were also fires of commensurate size in the arctic, raging in Siberia, Alaska, Canada and Greenland. In Siberia alone, four million hectares of forest were destroyed. These fires are attributed to the sudden thawing of permafrost, and the increase in lightning strikes in the tundra due to climate change. By 2100, the number of fires in the arctic tundra and boreal forests could increase to up to four times the current amount. Additionally, every fire emits more greenhouse gases into the atmosphere, which in turn can amplify climate change and can further increase fire probability. This vicious cycle amplifies the effects of climate change and makes it imperative that it be addressed head-on before conditions worsen even more significantly. This is a problem which has been discussed regarding the fires in the Amazon, and is being discussed again regarding the fires currently raging in Australia (readers, stay tuned for an upcoming SKEPTIPOL article on that).
Of course, there is a solution to all this: preventing human-caused climate change at all costs would undeniably alleviate the threat posed by arctic permafrost thaw. Unfortunately, this simple solution is incredibly difficult to achieve. Scientists and policy makers do not have clear solutions to the problem, and how to address the complex social, political, and economic factors that make climate change a nightmare to solve. We have no answers – at least, not yet. So we have to ask ourselves a tough question: which nightmare would we prefer to experience? A world already experiencing the devastating consequences of human-made climate change? Or a world struggling to contain the threats of climate change before they fully materialize? The answer to that question: only you can decide; the future is in your hands.
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2. Ellen Gray. (2018). Unexpected future boost of methane possible from Arctic permafrost. NASA Climate Change: Vital Signs of the Planet. Retrieved January 23, 2020, from https://climate.nasa.gov/news/2785/unexpected-future-boost-of-methane-possible-from-arctic-permafrost/
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4. UCAR. (2012). Methane | UCAR Center for Science Education. Retrieved January 23, 2020, from https://scied.ucar.edu/methane
5. US EPA. (2019). Overview of Greenhouse Gases | Greenhouse Gas (GHG) Emissions | US EPA. Retrieved January 23, 2020, from https://www.epa.gov/ghgemissions/overview-greenhouse-gases#methane
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