Melting permafrost in Siberia after last year’s heatwave could release ‘methane bomb’

The 2020 heatwave that occurred during the summer in Siberia led to an increase in methane gas emissions from limestones, an event that could lead to Earth’s atmosphere getting hit with a ‘methane bomb.’

A new study from researchers at the University of Bonn found that the extreme heatwave in Siberia resulted in a ‘temperature anomaly’ of 6 degrees Celsius over the baseline time period of 1979-2000.

Since June 2020, there has been an increase in methane concentration in two long areas in the region: the Taymyr Fold Belt and the rim of the Siberian Platform.

In early 2021, the methane had spread all over the region, the researchers found. 

The extreme heatwave resulted in a ‘temperature anomaly’ of 6 degrees Celsius over the baseline time period of 1979-2000. Since June 2020, methane concentration has increased in Taymyr Fold Belt and the rim of the Siberian Platform

What is concerning about the two areas is that the bedrock has been formed by limestone formations from the Paleozoic era, dating as far back as 541 million years ago. 

In early 2021, there was methane all over the area, as methane spread. The bedrock has been formed by limestone formations from the Paleozoic era, dating as far back as 541 million years ago

‘Methane is particularly dangerous here because its warming potential is many times higher than that of CO2,’ the study’s lead author, University of Bonn professor Dr Nikolaus Froitzheim said in a statement.  

According to the Environmental Defense Fund, methane has 80 times the warming power that carbon dioxide does over the first 20 years it hits the atmosphere.   

The researchers compared spatial and temporal distribution of methane concentrations in the air of northern Siberia with geological maps to come up with their findings. 

Approximately 15 percent of the Northern Hemisphere or 11 percent of the entire globe is covered by permafrost, according to an April 2021 study. 

If this portion of the ground were to thaw due to climate change, it could be especially worrisome, given the implications it would have on rising temperatures. 

Previous research suggested that a thawing of the permafrost would contribute to a rise of ‘only’ 0.2 degrees Celsius by 2100 and would not lead to the aforementioned ‘methane bomb,’ but the new study challenges that assumption. 

Froitzheim noted that the soil formation in these areas are ‘very thin to nonexistent,’ so there is little to worry about methane from decaying soil.

However, the fracture and cave systems in the limestone are likely to become porous with higher temperatures.  

‘As a result, natural gas being mainly methane from reservoirs within and below the permafrost can reach the Earth’s surface,’ he explained.

Frotizheim continued: ‘The estimated amounts of natural gas in the subsurface of North Siberia are huge. When parts of this will be added to the atmosphere upon thawing of the permafrost, this could have dramatic impacts on the already overheated global climate.’ 

The study has been published in the journal Proceedings of the National Academy of Sciences. 

Several groups of scientists have expressed concerns about what would happen if Earth’s permafrost were to melt.

In July 2020, a separate group of experts found that increased permafrost melt could result in microbes releasing 40 billion more tons of carbon dioxide into the atmosphere than previously thought.

Other studies, including one published in September 2017, have expressed concern about the unlocking of ancient diseases that are trapped in the permafrost. 

THREATS POSED BY THAWING PERMAFROST  

Permafrost, mostly found in high-latitude regions like the Arctic, stores large quantities of carbon dioxide and methane, which are released into the atmosphere if the soil melts and decomposes. 

As permafrost melts and releases gases into the atmosphere which cause warming, permafrost melts even more, releasing more of these gases such as methane and CO2, leading a positive feedback loop that worsens climate change. 

But other threats posed by melting permafrost include:

• Release of ancient microbes: In August 2016, an anthrax outbreak in Siberia caused 72 people to become sick, and killed a 12-year-old boy. This was because an anthrax-infected reindeer had thawed, releasing the bacteria.
• Damaged landscapes and roads: When the ice in the permafrost thaws, the water runs off and the ground above can slump, deform, or fall apart. The Alaska Dispatch News has reported that thawing permafrost is warping roads in Bethel, Alaska.
• Loss of historical records: Thawing permaforst could also threaten natural historical records. For example, ‘Otzi’, a 5-300 year-old dead man found in the Alps, would not have been so well preserved if he had thawed.

As permafrost melts and releases gases into the atmosphere which cause warming, permafrost melts even more, releasing more of these gases such as methane and CO2, leading a positive feedback loop that worsens climate change