The Earth faces a looming crisis. Globally, temperatures are rising. Heatwaves, droughts, ocean acidification, and rising sea levels are on the horizon. Around 90% of the world lives in the northern hemisphere with major population centers in the tropical and subtropical regions. These regions will be severely affected.

What is permafrost?

• Permafrost is ground that remains completely frozen at 0 degrees Celsius or below for at least two years and is defined solely based on temperature and duration.
• It is composed of rock, sediments, sand, dead plant and animal matter, soil, and varying degrees of ice and is believed to have formed during glacial periods dating several millennia.
• It is mainly found near the polar zones and regions with high mountains covering parts of Greenland, Alaska, Russia, Northern Canada, Siberia and Scandinavia. 
• Its thickness reduces progressively towards the south and is affected by a number of other factors, including the Earth’s interior heat, snow and vegetation cover, presence of water bodies, and topography.

How does permafrost form?

• Just as a puddle of water freezes on a frigid winter night, water that is trapped in sediment, soil, and the cracks, crevices, and pores of rocks turns to ice when ground temperatures drop below 32°F (0°C).
• When the earth remains frozen for at least two consecutive years, it’s called permafrost. If the ground freezes and thaws every year, it’s considered “seasonally frozen.”

What is the composition of permafrost?

• Permafrost is made of a combination of soil, rocks and sand that are held together by ice. The soil and ice in permafrost stay frozen all year long.
• Near the surface, permafrost soils also contain large quantities of organic carbon—a material leftover from dead plants that couldn’t decompose, or rot away, due to the cold.
• Lower permafrost layers contain soils made mostly of minerals.
• A layer of soil on top of permafrost does not stay frozen all year. This layer, called the active layer, thaws during the warm summer months and freezes again in the fall.

Permafrost thawing

• When permafrost thaws, water from the melted ice makes its way to the caves along with ground sediments, and deposits on the rocks.
• In other words, when permafrost thaws, the rocks grow and when permafrost is stable and frozen, they do not grow.

Why thawing?

• The link between the Siberian permafrost and Arctic sea ice can be explained by two factors:
• One is heat transport from the open Arctic Ocean into Siberia, making the Siberian climate warmer.
• The second is moisture transport from open seawater into Siberia, leading to thicker snow cover that insulates the ground from cold winter air, contributing to its warming.
• This is drastically different from the situation just a couple of decades ago when the sea ice acted as a protective layer, maintaining cold temperatures in the region and shielding the permafrost from the moisture from the ocean.
• If sea ice (in the summer) is gone, permafrost starts thawing.

How much of the earth’s surface is permafrost?

• In the northern hemisphere, permafrost covers an estimated 9 million square miles—nearly the size of the United States, China, and Canada combined. However, that footprint is rapidly shrinking.
• While global warming is upping temperatures around the world, the Arctic is warming twice as fast as anywhere else—and faster than it has in the past 3 million years.
• And when surface air temperatures rise, below-ground temperatures do, too, thawing permafrost along the way.
• Scientists estimate there is now 10 percent less frozen ground in the northern hemisphere than there was in the early 1900s. With every additional 1.8°F (1°C) of warming, an additional 1.5 million square miles of permafrost could eventually disappear.
• Even if we meet the climate targets laid out during the 2015 Paris climate talks, the world may still lose more than 2.5 million square miles of frozen turf.

Associated issues with the Thawing of Permafrost

Worsen the effects of the climate crisis

• In the Arctic, temperatures are rising twice as fast in other parts of the world. As a result, the thick layer of soil called permafrost that has remained frozen throughout the year is thawing.
• The Permafrost contains vast amounts of carbon. Roughly about 60% of the world’s soil carbon is held in just 15% of the global soil area. This is estimated to be about 1.5 trillion metric tons of carbon.
• The thawing of permafrost will worsen the effects of the climate crisis, because stored carbon will be released in the process.
• Likewise, the loss of sea ice and ice sheets covering land will accelerate the rise in temperatures. White ice reflects sunlight keeping the planet cooler, whereas darker seawater absorbs heat.

• Experts believe this process may have already begun. Giant craters and ponds of water (called ‘thermokarst lakes’) formed due to thawing have been recorded in the Arctic region. Some are so big that they can be seen from space.
• Scientific estimates suggest that the Arctic Ocean could be largely sea ice-free in the summer months by as early as 2030, based on observational trends, or as late as 2050, based on climate model projections.
• A study has shown that every 1 degree Celsius rise in temperature can degrade up to 39 lakh square kilometer due to Permafrost thawing ( the ice inside the permafrost melts, leaving behind water and soil).

Higher latitudes will face challenges hitherto faced by tropical areas

• Increase of average temperatures is modifying the environment in other ways too.
• Diseases that have typically afflicted the equatorial belt are spreading up into higher latitudes. Mosquitoes, ticks, and other insects spread many of these diseases.
• The West Nile virus causes hundreds of deaths every year in the United States, where it was first reported in 1999. With rising temperatures, West Nile will become more prevalent in Canada, including parts of the Arctic.
• Warming temperatures are also causing changes in the habitats of wild birds such as ducks and geese that can carry avian flu.
• Earlier this year, Russia reported the first case of the H5N8 avian flu passing from birds to humans. Changes in habitats of other wild animals such as foxes might also increase the geographic distribution of rabies.

Rise of viruses and bacteria

• Scientists are also concerned about the rise of viruses and bacteria from thawing permafrost and ice. In the summer of 2016, there was an outbreak of anthrax in a remote part of Siberia.
• Dozens of people were infected, and a young boy was killed. Around 2,300 reindeer perished in the outbreak.
• Spread:

1. Anthrax is a serious infectious disease caused by bacteria that can remain dormant as spores. Spores of anthrax can remain viable for at least a few decades in frozen soil and ice.
2. A plausible idea of how the outbreak started is that record temperatures that year caused a frozen reindeer carcass infected with anthrax spores to thaw.
3. And as carcasses of other animals (including those of extinct mammoths) thaw, we might see more disease outbreaks.

Potential to cause epidemics

• Another concern is the emergence of viruses and bacteria with the potential to cause epidemics. These disease-causing microbes might be dormant for hundreds or even thousands of years.
• Genetic material from the H1N1 influenza virus that caused the Spanish Flu pandemic of 1918, as well as that of smallpox have been recovered from permafrost.
• The reemergence of a virus like smallpox (which is the only human disease to have been eradicated) would be disturbing since humans are no longer routinely vaccinated.
• Infectious viruses and bacteria can be resurrected from frozen ice, soil, animal carcasses, and human corpses.
• In 2014, researchers reported the discovery of giant viruses that had been dormant in Siberian permafrost for around 30,000 years.

Tibetan Plateau and the virus samples

• These conditions are not restricted to the Arctic alone either. Glacial ice that has persisted for thousands of years is melting.
• Recently, the journal Microbiome reporting 15,000-year-old-viruses (including 28 different kinds identified for the first time) that they found in glacial ice from the Tibetan Plateau.

 The threat to infrastructure

• Thawing permafrost is also ominous for man-made structures overhead.
• The Russian oil leak occurred recorded temperatures in Siberia at more than 10 degrees Celsius above average, and called them “highly anomalous” for the region where the power plant is located.
• As temperatures rise, the binding ice in permafrost melts, making the ground unstable and leading to massive potholes, landslides, and floods.
• The sinking effect causes damage to key infrastructure such as roads, railway lines, buildings, power lines and pipelines.
• These changes also threaten the survival of indigenous people, as well as Arctic animals.

Altered landscapes

• Thawing permafrost alters natural ecosystems in many ways as well. It can create thermokarsts, areas of sagging ground and shallow ponds that are often characterized by “drunken forests” of askew trees.
• It can make soil—once frozen solid—more vulnerable to landslides and erosion, particularly along coasts.
• As this softened soil erodes, it can introduce new sediment to waterways, which may alter the flow of rivers and streams, degrade water quality (including by the introduction of carbon), and impact aquatic wildlife.
• Wetlands also deteriorate along with permafrost, as the water sinks further underground without a frozen buffer to keep it in place
• This can create drier terrain more susceptible to wildfires, which expose even more permafrost to warming.

How Can We Stop Permafrost from Thawing?

Greenhouse gas emissions need to be arrested

• In order to curtail climate change and save the permafrost, it is indispensable that global CO2 emissions be reduced by 45% over the next decade, and that they fall to zero after 2050.
• To mitigate climate change, there is a need to take a global collective action. If one country cuts its emissions, that is going to be of little use if the others do not follow suit.

Slow down erosion

• The scientific journal Nature suggested building a 100-metre-long dam in front of the Jakobshavn glacier (Greenland), the worst affected by Arctic melting, to contain its erosion.

Refreeze the Arctic

• Indonesian architect has won an award for his project Refreeze the Arctic, which consists of collecting water from melted glaciers, desalinating it and refreezing it to create large hexagonal ice blocks.
• Thanks to their shape, these icebergs could then be combined to create frozen masses.

Strengthening their consistency

• Some researchers propose a solution to manufacture more ice. Their proposal consists of collecting ice from below the glacier through pumps driven by wind power to spread it over the upper ice caps, so that it will freeze, thus strengthening the consistency.

People’s awareness and policy intervention

• The tundra and the permafrost beneath it may seem far away, but no matter where we live, the everyday choices we make contribute to climate change.
• By reducing our carbon footprint, investing in energy-efficient products, and supporting climate-friendly businesses, legislation, and policies, we can help preserve the world’s permafrost and avert a vicious cycle of an ever-warming planet.

Conclusion

• For most of us, the tundra and the permafrost beneath it may seem a million miles away. But no matter where we live, the everyday choices we make that contribute in some small way to climate change collectively can add up to a big impact on the world’s coldest climes.
• By reducing our carbon footprint, investing in energy-efficient products, and supporting climate-friendly businesses, legislation, and policies, we can help preserve the world’s permafrost and avert a vicious cycle of an ever-warming planet.
• To be clear, the chances of an epidemic originating from microbes originating from permafrost or ice is low. But as the Covid-19 pandemic has demonstrated, even low probability events with major consequences need to be taken seriously.