Context: 

• The Batagaika crater, the world’s largest permafrost crater, is expanding at an alarming rate due to the thawing of the permafrost, a phenomenon catalysed by global warming.

About  Batagaika crater:

• Location: The crater is located in the Sakha Republic.
  • Sakha is the largest republic of Russia, located in the Russian Far East, along the Arctic Ocean
• It is a one-kilometre-long gash that reaches depths of up to 100 metres. 
• It began forming in the 1960s after deforestation led to the melting of the underground permafrost, causing the land to sink.

What is Permafrost?

• Frozen Region: Permafrost is a type of ground or soil that remains frozen at or below the freezing point (0 degrees Celsius or 32 degrees Fahrenheit) for two or more consecutive years. 
• High latitude regions: It is found in regions where the temperature remains consistently cold throughout the year, typically in high-latitude regions near the poles, such as in the Arctic and subarctic regions.

Impact of permafrost thawing:

• Infrastructure Damage: The thawing permafrost has had devastating effects on northern and northeastern Russia, causing infrastructure damage such as buckling roadways, splitting houses, and disrupting pipelines. 
• Release of greenhouse gases: The permafrost holds gigatonnes of methane and carbon dioxide in the subsoil.
  • Accelerating Warming: Their gradual release would lead to an acceleration of global warming which in turn would accelerate the melting of the remaining permafrost, a phenomenon known as the permafrost carbon feedback cycle.
• Release of viruses and bacteria: Scientists have found microbes that are over 400,000 years old in permafrost.Many of the viruses that have plagued humanity such as bubonic plague and smallpox are believed to lie dormant in this frozen stratum.
• Damage to ecosystems and their biodiversity: Melting Siberian permafrost is turning tundra into muddy landscapes, killing local flora and starving wildlife that feeds on it.
  • When permafrost beneath lakes melts, water seeps into the ground and disappears, causing droughts.
• Landslides and geological accidents: Cities built on permafrost can experience landslides as the cement-like ice melts. The Batagaika crater, caused by thawing permafrost and deforestation, best illustrates the problem.

News Source: India Today