Permafrost is permanently frozen ground that covers nearly one-quarter of the Northern Hemisphere. It’s a combination of soil, rocks and sand held together by ice. However, recent rising temperatures – a result of global warming – have begun to melt the ice. In fact, climate change disproportionately affects the Arctic, making it an increasingly threatening danger to the security of the permafrost.
The permafrost contains an estimated 1500 gigatons of carbon, approximately twice the amount currently found in the atmosphere. If the permafrost continues to melt, the release of its carbon dioxide will exacerbate global warming and worsen the already dire conditions. To further illustrate, the permafrost is predicted to release the same amount of carbon dioxide as the world’s major nations if it continues to melt.
The danger of the permafrost stems from its feedback loops. As global temperatures rise, the thawing of the permafrost accelerates. This, in turn, causes the global temperature to rise even further as more carbon dioxide is released into the atmosphere. This cycle is known as a positive feedback mechanism. When ice-rich ground collapses, thermokarst lakes form. There, pools of water further accelerate the thaw of the permafrost. Currently, the permafrost acts as a major carbon sink; however, predictions suggest that a 3-degree Celsius increase in temperature will output 280 gigatons of carbon dioxide and 3 gigatons of methane.
Moreover, most models likely underestimate the speed of change. They focus only on the abrupt thaw which fails to take into account the constant slow thaw. Additionally, permafrost carbon isn’t accounted for in some general climate models, meaning we could reach thresholds sooner than expected.
Potential costs of the permafrost melt are also an issue, as 70% of infrastructure in the region is estimated to be at risk. Buildings and roads are already at risk and have begun to degrade and show permafrost damage. Furthermore, the melting of the permafrost would put indigenous and Arctic communities at risk of displacement.
Finally, the permafrost presents potential biological threats. When the permafrost thaws, so do ancient bacteria and viruses, releasing newly unfrozen microbes that could make humans and animals sick if exposed to them. Arctic transportation lanes mean that these possible diseases would have the potential to spread all over the world.
One potential solution is to rewild the Arctic permafrost by reintroducing megafauna and plants. Numerous studies have shown a correlation between the presence of megafauna and ecosystem resilience. Because the grasslands reflect light better, the integration of this fauna may help slow ice melt. Furthermore, they can increase insulation and moisture levels within the soil, which in turn, could increase the current amount of carbon captured within the soil.
Looking to the near future, researchers estimate that a 1-degree Celsius increase in global warming could release as much carbon as 35 million cars emit in a year through thawing permafrost. As climate change progresses, scientists say permafrost thaw may become an increasingly important factor in future climate projections.
