Permafrost, soil that is permanently frozen, is found primarily in the high latitudes of our planet. It is estimated that approximately 24% of the land in the Northern Hemisphere is composed of permafrost . Permafrost is also present to a lesser extent in the Southern Hemisphere.
Permafrost’s role in climate change
Permafrost contains large amounts of stored carbon dioxide and methane, both of which are powerful greenhouse gases . Methane (a carbon-based greenhouse gas) is approximately 20-30 times more powerful at trapping atmospheric heat than carbon dioxide is .
The methane in the permafrost that could be released would be produced from melting frozen organic matter that would readily decompose as global atmospheric temperatures rise. Approximately one-third of the Earth’s soil carbon is currently stored in the Arctic’s permafrost soil .
It has been found in recent years that as global temperatures have steadily increased due to climate change, the permafrost soil layer is thawing and melting at increasing rates each summer .
The consequences of thawing permafrost include:
- Subsidence of the ground
- Alterations in the composition of plants that are able to grow in the thawed ground
- Alterations in wildlife habitat
- Negative impacts upon communities that live on permafrost soil
Under normal atmospheric conditions, changes in permafrost typically take hundreds of years. However, due to the current warming trend of the global climate, it has been estimated by the Intergovernmental Panel on Climate Change (IPCC) that under a business as usual scenario, the permafrost in the northern hemisphere will be reduced by 20-30% by the mid-21st century .
Early indications of this extensive permafrost thawing have already begun, as an increased amount of permafrost is melting each year during the summer season and the permafrost is progressively becoming less “permanent” .
Because the permafrost stores a great deal of carbon dioxide and methane, as it melts it will release more greenhouse gases into the atmosphere, accelerating the greenhouse effect and global warming. Sadly, this process could greatly increase as soon as during the mid-2020s as the Arctic tundra converts from a global carbon sink into a global carbon source, and this could result in runaway atmospheric warming .
Because there have been few climate models to date that incorporate the possibility of released methane gases from the melting permafrost, climate change impacts could result in even more extreme conditions than most climate change projections have previously predicted.
Peatlands, which contain dead organic matter that is rich in carbon, are also present beneath the permafrost layer in many areas. If the permafrost layer melts and the organic matter in the peatlands decomposes, the peatlands themselves could release an estimated 38-100 million tons of carbon per year into the atmosphere .
In addition, methane hydrates, methane gas “bubbles” that are frozen in ice between layers of permafrost that are abundant in certain areas within the Arctic Shelf, could also be released if the permafrost melts, potentially resulting in an estimated 400 billion ton release of carbon-equivalent into the atmosphere .
So what can we do?
Obviously, such dire predictions for our planet are ones that we must never accept nor settle for. Humanity must do absolutely everything possible right now to significantly reduce our negative impacts on the climate.
We must all do our part to keep the permafrost from melting by cutting our use of fossil fuels and to adjust our lifestyles in ways that do not negatively impact our climate any further.
This will require broad a consensus around the world to take swift action as well as sweeping changes regarding how we live our lives and run our economies. While these requirements may seem like insurmountable tasks, we have the tools at our disposal right now to take decisive actions on climate change.
In order to have a sustainable future for life on Earth, this swift action is truly the only feasible path forward.
Let us all be a part of the solution before it’s too late.