What is Permafrost?

In this blog post, we will talk about what permafrost is, why its melting is important and what kind of dangers it brings. Permafrost is a layer of earth that stays frozen throughout the year. In other words, it refers to the areas where the soil continuously remains frozen in cold areas such as ice.

So, why is melting of this frozen soil so important and dangerous? The simplest explanation is that when permafrost melts, excessive amounts of greenhouse gas are emitted, and this accelerates climate change. Moreover, it causes serious problems such as infrastructure damage and ecosystem changes. Continue reading for more!

What is Permafrost, Where is it Found?

​Permafrost refers to the ground which remains frozen for at least two years - it includes sand, soil, or rocks. Permafrost can be either on land or even at the ocean bed and could have been frozen for hundreds, even thousands of years. However, permafrost is different compared to the ground which freezes in the winter and thaws in the summer. Permafrost refers to the grounds which remain frozen despite seasonal changes. In some areas, the depth of permafrost can go up to 1.7 kilometers. Covering large areas such as the whole of North Pole tundra, permafrost can also be found in smaller areas such as on the side of a mountain which receives wind or on the peak of a mountain.

Almost one fourth of the soil in the Northern Hemisphere, which has more land, consists of permafrost. It is found in large areas such as Canada, Greenland, northern regions of Siberia, and the bed of Arctic Ocean. Approximately 85% of the land in Alaska is frozen. Permafrost is also found in the Andes and the Southern Alps of New Zealand in the Southern Hemisphere.

Description of Permafrost

Permafrost was first termed by Simeon William Mueller in 1943 in the United States Geological Survey (USGS) report. Mueller indicated that permafrost problem needs to be dealt with during the construction of Trans-Siberia railway and compiled most of this information from the Russian engineering reports from 19th century.

Permafrost layer starts where the ice ends, however it can also be found under the layer called as “active layer” by scientists. This is a layer consisting of soil, sand, rock, or a combination of these which can freeze and thaw seasonally or monthly depending on the rainy or sunny weather conditions. When an active layer is in question, it is needed to dig almost one meter or more to find the frozen soil under it. And this means that there are various areas in which permafrost can be found such as on the surface, under an active layer or under ice or snow layers that can vary throughout the year. These changes can be seasonal, and they can be impacted by weather conditions and geothermal activities.

Permafrost - in general - is found only in places where annual average weather temperatures are low, for example at or below the freezing point of water: 0 centigrade degree. However, unique local and historical conditions have shown that permafrost can also be found in areas with higher average temperatures.

What are the Types of Permafrost?

Permanent Permafrost: If 90% - 100% of the ground of a land is frozen, this is called “permanent permafrost”. There is a “permanent permafrost line” representing the southernmost points of a land covered with permafrost or glaciers in the Northern Hemisphere. This line does not have a corresponding line in the Southern Hemisphere since the corresponding area is under the ocean.

Impermanent Permafrost: “Impermanent permafrost” is the state in which 50% - 90% of the ground remains frozen. The “impermanent permafrost” state happens when the ground stays cold, however weather temperatures vary seasonally. In some areas, some soil layers melt in summer months while some shaded or protected areas may remain frozen.

Irregular Permafrost: When permafrost layer of a region is less than 50%, this area is accepted as “irregular permafrost”. This occurs at places similar to impermanent permafrost, however maybe at lower altitudes or in areas exposed to warm air currents.

Does Permafrost Melt?

Today, permafrost still covers large areas. Permafrost in the Northern Hemisphere is estimated to cover an area of 14 million km2, i.e., the total area of the USA, Canada, and China. However, permafrost across the world is increasingly shrinking. So, why is this important?

Scientists are startled by the faster-than-expected melting of permafrost since the North Pole warms almost twice as fast compared to more temperate regions and permafrost is sensitive to even the little changes in temperature.A study published in the Nature magazine estimates that permafrost will shrink by 40% in case the globe warms by more than 2 °C.

Permafrost and Climate Crisis

Melting of permafrost is thought to have a few impacts; first one is the emission of greenhouse gases into the atmosphere as it melts, particularly methane, which will create a feedback cycle - the more permafrost melts, the more heated gases will be released to the atmosphere and climate will be warmer. The second one is the fact that melting of permafrost will disturb the balance of buildings and transportation systems, trigger events such as destructive floods or landslides/mudslides and create local impacts.

For more information about Greenhouse Gases, check out our blog post here.

In addition to the ecological consequences, economic problems also emerge as communities living on permafrost start to lose their buildings. For example, melting of permafrost in Alaska, Greenland, Canada, and Russia cause houses and buildings to collapse or sink. Structural integrity of 40% of the buildings in the city of Vorkuta in Russia is in jeopardy. And in the city of Norilsk with a population of 175,000, 60% of the buildings are damaged by the melting of the frozen soil and 10% of the houses in the city are already abandoned. Moreover, changing underground conditions with the melting of permafrost present a challenge for reconstruction. Few houses are located in the majority of these type of places. Furthermore, the majority of the affected people consists of native population living in these regions for thousands of years.

According to a new study, melting-thawing of permafrost can seriously damage the infrastructure in the Northern Hemisphere and this can impact approximately 3.6 million people. A study published in the Nature Communications indicates that approximately 70% of infrastructure in the Northern Hemisphere is built over permafrost and this infrastructure includes houses, hospitals, roads, railroads, industrial zones. Three quarters of the population living on permafrost in the Northern Hemisphere - which corresponds to approximately 3.6 million people - will be harmed by this situation in the next 30 years, according to the study.

Potential Ecological Consequences of Permafrost Melting

Melting of permafrost changes the ecological landscape. As frozen soil in Canada, North Pole, Alaska, Russia and other places thaws, rich areas that once provided food for grizzly bears, caribous and other animals disappear under mounds of dirt. Cranberries, bushes, lichens, and other edible plants which are nutritional resources for animals decompose in the muddy environment.

Permafrost’s Impact of Increasing Greenhouse Gas Emissions

Permafrost melting triggered bey human-caused climate change can create a dangerous cycle. According to a study published in the Nature magazine, an estimated amount of 1,400 gigatons of carbon is contained in the permafrost only in the North Pole and the emission of this carbon into the atmosphere is occurring faster than expected.

If carbon emissions continue at this rate, this amount needs to be factored in the global emission calculations which is used by scientists to better understand future impacts of climate change. More greenhouse gas emissions occur as permafrost melts, global warming accelerates, and this leads to a cycle in which more permafrost melts and more gases are released into the atmosphere.

Permafrost, Viruses, and Bacteria

Some organisms can live thousands of years inside the ice. The conditions are near perfect - cold, dark, and low oxygen environments mean that some of these microscopic cells can survive. Viruses, fungi, and bacteria frozen inside permafrost can become active after they mix in the water resources with the melting waters.

This situation emerged in 2016, with the thawing of a reindeer carrying anthrax which was buried in the frozen soil for 75 years. And the 1918 Spanish flu virus was found in the unspoiled corpses found in Alaska, even some 40,000-year-old worms were revived after thawing. The dimensions of the diseases that can originate from the antique viruses and bacteria hidden in the permafrost are not known.

Economic Impacts of Permafrost Melting

It seems that finding food will be increasingly challenging for the native populations such as Inuit living in the regions where permafrost melts due to thousands of collapses and thermokarst landslides which occur already, and which may occur in the future. Changes in landforms and changes in seacoasts via collapses can be seen with the impact of melting of permafrost. Other potential consequences include variation of direction of rivers and draining of lakes. All these events will negatively impact wildlife which we depend on as humans.

Melting of permafrost can also cause buildings and roads which are in need to be reconstructed or abandoned to collapse, and damage on all kinds of commercial activities from oil and gas drills to pipelines as well as damage on all the other businesses and communities which depend on a firm ground and a reliable water resource.

Unexpected Consequences of Permafrost Melting

The melting of permafrost can also reveal remains of old civilizations, animals and world history which have been buried underground for thousands of years. Although the discovery of a 3,000-year-old Siberian prince in a remote area can be seen as a blessing by archaeologists who study that time period and place, this situation which will trigger climate crisis in general represents a phenomenon that should be taken into account.

Why is it Important to be Aware of Permafrost?

The melting of permafrost is a serious matter which is of interest not only to scientists but all of us. Greenhouse gases to be released into the atmosphere, infrastructure damages, ecological changes, and dangers such as potential health risks to emerge when it melts indicate more extensive consequences of global warming and climate change. In this post, we dealt with what permafrost is, where it is found and the dangers brought with its melting. Becoming aware of and taking action for climate crisis is one of the most important steps we can take for our future. We hope that this post provided you with some valuable information about permafrost and climate change. See you in our future posts!