[INFORMATIVE] A Look Into Permafrost Thawing

A Look Into Permafrost Thawing

By: Eddie Li

What is Permafrost Thawing?
Permafrost is a kind of ground that has been continuously frozen for at least two years, extending deep below the Earth’s surface. It occurs when ground temperatures decrease to below 0 degrees Celsius (32 degrees Fahrenheit) so that water in sediment, soil, and rocks freeze into ice. Permafrost composes 1/4 of the Northern Hemisphere, where it is predominantly located in the Arctic regions of Siberia, Canada, Greenland, and Alaska. In fact, 85% of Alaska is covered with permafrost. Permafrost is also located in the Tibetan plateau, high-altitude regions such as the Rocky Mountains, and the Arctic Ocean floor as undersea permafrost. In the Southern Hemisphere, permafrost is located in mountainous regions such as the South American Andes, New Zealand’s Southern Alps, and below Antarctica. In total, according to NSIDC (National Snow and Ice Data Center), permafrost covers approximately 9 million square miles, including 24% of the land surface in the Northern Hemisphere.

In addition to being geographically significant, permafrost plays an important role in its respective ecosystem, holding half of all organic carbon stored within Earth’s soil. However, temperatures are increasing twice as fast in the Arctic than the rest of the world due to global warming, faster than it ever has been in the past 3 million years. With increasing surface air temperatures, below-ground temperatures are increasing as well. In fact, permafrost temperatures are increasing at a faster rate than the temperature of the air of the Arctic. In the last 30 years, permafrost temperatures have increased from 1.5 to 2.5 degrees Celsius. As a result, permafrost layers are thawing and melting. Today, according to NSIDC scientists, there is approximately 10% less frozen ground in the Northern Hemisphere than there was during the early 1900s. 30 to 85% of the permafrost layer covering the Arctic region could be thawed and melted if global temperatures increase by 3 degrees Celsius. It is even suggested that 1.5 million square miles of permafrost could eventually disappear for every additional 1 degree Celsius (1.8 degrees Fahrenheit) of warming.

What are the Impacts of Permafrost Thawing?
Environmental Effects
Organic matter such as dead plants and animals are trapped inside permafrost. In total, permafrost contains 1700 billion tonnes of carbon, which is double the amount of carbon in Earth’s atmosphere and 4 times more than the carbon emitted by anthropogenic activity since the Industrial Revolution. If it thaws, microbes will eat the organic material to decompose their bodies, causing decay and release of carbon dioxide, methane, and other greenhouse gasses into the atmosphere. In fact, permafrost thawing may cause a potentially unyielding positive feedback loop. As a result, global warming and climate change would be further amplified by permafrost thawing to create even more severe environmental consequences in the Arctic and Earth’s ecosystem. The Arctic is actually now emitting more carbon than it is absorbing due to permafrost thawing, even though it was considered a carbon sink.

Due to permafrost thawing, frozen earth is transforming into ponds and swaps, which would act as a positive feedback loop to continue to accelerate permafrost thawing. In 2015, a study named “Permafrost Stores a Globally Significant Amount of Mercury” published in Geophysical Research Letters stated that the Arctic permafrost contains a large storage of natural mercury, which is a potent neurotoxin. It is estimated that 15 million gallons of mercury is stored in permafrost, which is twice the amount of mercury in the ocean, atmosphere, and other soils. Once released, mercury can spread through water and air into ecosystems to alter their nature negatively. Soil is also more vulnerable to landslides and erosion, particularly along coasts. As well, sediment in waterways may alter the flow of rivers and streams, degrade the quality of water (along with the release of carbon), and negatively affect wildlife. In addition, wetlands are disappearing because of permafrost thawing as water sinks underground without a frozen barrier, creating dry terrain more vulnerable to wildfires, which would lead to further permafrost thawing – another example of a positive feedback loop. Furthermore, permafrost thawing would further contribute to rising sea levels. If all of Earth’s permafrost thaws, sea levels could rise by approximately 4 inches, doubling the risk of flooding cities such as San Francisco, Seattle, and Los Angeles.

Social/Economic Effects
While permafrost thawing may have environmental effects, it also has social and economic effects. It can change not only the terrains and ecosystems unique to Earth but also the landscape of the homes of 35 million people, causing erosion, destabilization of infrastructures leading to destroyed homes and roads, flooding hazards, forced migration, and even diseases. Permafrost thawing is observed to cause receding shorelines, destabilizing the ground, flooding, and overall negative health effects.

Receding shorelines are caused by permafrost thawing due to a weakening ice barrier along the Arctic coastline that protects the land from storms. As a result, a storm can erode more than 20 metres of shoreline. Some Arctic islands, especially those in northern Russia, may disappear into the sea soon. In Alaska and northern Canada, people have been displaced from their homes and towns due to the ocean being closer to their rooted lives.

Destabilized ground is caused by permafrost thawing due to the soil continuously contracting when the ground thaws, and then expanding when it freezes again. As a result, movements in the ground damage critical urban infrastructures, including roads, pipes, buildings, railroad tracks, and other connected infrastructures, inevitably displacing communities. For example, in Russian Arctic cities, more than half of the buildings have been damaged by the continuous movement in the soil. In remote Russian regions, large craters have been discovered, caused by methane eruptions from thawing permafrost. Furthermore, in the Canadian Arctic, a housing crisis is caused by infrastructure damage, with a dramatic increase in rent rates. In fact, permafrost thawing has cost Canada tens of millions of dollars in damage to public infrastructures in the Northwestern Territories. Moreover, permafrost thawing is causing increased instances of unprecedented flooding due to the transformation of solid, frozen ground into ponds and swamps, especially in the communities in North America and the Russian Arctic.

Indigenous communities residing in the Arctic have been particularly affected by permafrost thawing. They are seeing their ancestral lands and burial grounds being flooded and ruined, and they themselves being displaced from their traditional homelands. The lifestyle, economies, food, and traditions of Indigenous peoples are incredibly threatened by the effects of permafrost thawing altering ecosystems and disarranging the familiar patterns in nature they have come to recognize over thousands of years and generations. For example, ice cellars, which are a key component in Indigenous lifestyles as a means of subsistence, are destroyed by the ground melting. The practice of storing food in frozen ground that has existed for thousands of years is now disrupted and causing community food stocks to rot, which further increases their high food insecurity.

There are also other regions, in particular, being affected by permafrost thawing. In Scandinavia, reindeer herders are experiencing difficulties due to changing lands. In Alaska, more than 30 communities face the imminent risk of displacement and the need for relocation away from erosion and floods. This could cost millions of dollars, further increasing housing insecurity in the Alaskan region. In Russia, it is a traumatic experience for Indigenous peoples residing in villages to be forced to relocate to cities when they have lived off the land for generations. Forced migration from rural villages to urban areas may lead to the dissipation of intergenerational knowledge, language, and traditions of Indigenous peoples, especially when it is further aggravated by discriminatory policies.

In addition to causing the displacement and deracinating of millions of people from their known homes and communities, permafrost thawing may lead to the reemergence of harmful bacteria and diseases that have been frozen in the Earth for hundreds of years. In 2016, an anthrax epidemic from rotting animal corpses as a result of permafrost thawing caused more than 70 people to be hospitalized in northern Russia, killing one child and more than 2,300 reindeer. As briefly mentioned before, mercury stored in permafrost may also potentially spread into food supplies. As well, Arctic wildfires due to the release of powerful greenhouse gases into the atmosphere from permafrost thawing could negatively affect the levels of air quality in other locations far away.

Global Importance
It is challenging to change and control permafrost thawing in a short period of time, especially given Earth’s circumstance with global warming and climate change. It seems that the concern of permafrost thawing transcends beyond the Arctic region and could spread its effects to the rest of the world. So, permafrost thawing may usually be depicted as an issue that, once reaching a particular critical level, the whole system of the Earth would collapse. However, whether the effects of permafrost on global warming and climate change is actually pivoting is a controversial issue in the research community. It was originally perceived that there is the idea of a “ticking carbon timebomb”. As a large reservoir of carbon and methane whose additional emissions as greenhouse gasses could substantially worsen our current circumstance of climate change on Earth, permafrost thawing is considered as one of those carbon timebombs. In fact, it was thought of that permafrost will initially experience gradual thawing due to global warming before reaching a critical threshold value that would trigger an increasing acceleration in the thawing process, leading to a quick and irreversible collapse of all of the permafrost across the Arctic. However, it remains ambiguous whether there is actually a temperature threshold value and if so, what that threshold is.

An international research team led by Dr. Jan Nitzbon from the Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research (AWI), conducted a study released in the journal Nature Climate Change that discovered that there are indeed particular physical, geological, and hydrological processes that may increasingly accelerate themselves and be irreversible. However, such processes only occur locally or regionally. For example, thermokarst lakes are formed from melting ice within permafrost soils, creating depressions in which meltwater is contained, and a dark lake that absorbs large amounts of solar energy. This consequently creates a self-sustaining, self-accelerating thawing process within the lake. The loss of boreal conifer forests due to Arctic wildfires caused by permafrost thawing is also another example of a similarly self-accelerating positive feedback loop.

Ultimately, there is no evidence that such increasingly accelerating processes at the local to regional scale are affecting the acceleration of all permafrost thawing globally, as well as global warming and climate change for that matter. Hence, it is misleading to depict permafrost thawing as some ticking carbon time bomb. Rather, there are local and regional critical moments that occur at different times, which may cause cumulative effects where permafrost thaws along with climate change. So, although it is only gradually increasing, global warming and climate change remain to be amplified by permafrost thawing. In fact, the study additionally suggests that there is no safety margin of warming that we could comply with. It is misleading to view that we can remain with our anthropogenic exploitation if we do not surpass the threshold value. Therefore, it is especially important for us today to closely examine and analyze the current patterns in the nature of permafrost thawing to confidently anticipate our next steps to save our Earth.


Works Cited
Alfred Wegener Institute. “Thawing permafrost: Research suggests it’s not a climate tipping point, but nevertheless has far-reaching impacts.” 3 June 2024, www.phys.org/news/2024-05-permafrost-climate-impacts.html. Accessed 18 Aug. 2024.

Bykova, Alina. “Permafrost Thaw in a Warming World: The Arctic Institute’s Permafrost Series Fall-Winter 2020.” The Arctic Institute, 1 Oct. 2020, www.thearcticinstitute.org/permafrost-thaw-warming-world-arctic-institute-permafrost-series-fall-winter-2020/. Accessed 19 Aug. 2024.Denchak, Melissa. “Permafrost: Everything You Need to Know.” NRDC (Natural Resources Defense Council), 26 June 2018, www.nrdc.org/stories/permafrost-everything-you-need-know. Accessed 19 Aug. 2024.