Earth’s permafrost is thawing and the consequences for the planet are concerning. Scientists estimate that 1,330 billion to 1,580 billion tons of organic carbon are stored within the permanently frozen soil of the Arctic and subarctic regions. As the Earth’s temperature increases, the previously frozen soil releases its long-trapped greenhouse gases into the atmosphere. This creates a positive feedback loop, in which these gases then further warm the climate, which then melts more permafrost, and so on. Over the past thirty years, the Arctic has warmed twice as fast as other regions and its thawing permafrost could accelerate the effects of climate change. While scientists have been aware of this cycle for quite some time, researchers have recently clarified how the powerful destabilizing effect of melting permafrost will unfold. In short, it could be worse.
A study conducted by researchers at Northern Arizona University and recently published in Nature tackles the tough question of how exactly the melting Arctic will affect Earth’s climate. “Our big question is how much, how fast and in what form will this carbon come out,” says Ted Schuur, lead author of the study. “Human activities might start something in motion by releasing carbon gases but natural systems, even in remote places like the Arctic, may add to this problem of climate change.” Climate change is a process that is still poorly understood and higher greenhouse gas levels may interact with an already complex biosphere in unpredictable ways. Determining how these systems may interact with each other and how climate change will manifest is essential to effectively dealing with its social and ecological consequences.
Schuur and his team compiled and analyzed data from recent climate studies to determine that it is most likely that the melting permafrost will release its greenhouse gases gradually over the course of several decades. This comes as welcome news to scientists who had once feared that the gases would be abruptly released, triggering an enormous global climate shift with extremely volatile results. However, much still remains unknown. Greenhouse gas emissions released from the permafrost could be far greater or smaller than even the most up-to-date research predicts. Scientists are also unsure of how the melting permafrost could affect the formation of lakes and wetlands, which may slow decomposition but could also increase methane gas emissions.
The NAU Nature report outlines steps that can be taken to further improve scientific understanding of permafrost carbon and the effects of its release, such as timely integrating the latest databases into climate models, developing better models to distinguish the effects of methane vs. carbon emissions, and continued in-depth observation of the Arctic as it melts. The more that scientists learn about climate change, the better prepared we all are for our wild future.