Microbes Threaten Climate Change With Methane From Thawing Permafrost


The issues and problems regarding climate change have been in the headlines and in front of lawmakers for decades. The main arbiters of the ever-increasing temperature of the Earth are fossil fuel-powered plants, vehicles, and industry. Though, there is one process that is also polluting the environment, which is the thawing permafrost in the Arctic, which is releasing methane and carbon dioxide, causing scientists to worry.

Scientists understand that permafrost could be a great threat to the Earth’s declining health. Permafrost, which is frozen soil, covers almost 25 percent of all land in the Northern Hemisphere, containing over 1,700 gigatons of unearthed carbon. Basic environmental processes cause this stored carbon to leak up into the atmosphere. When the permafrost slowly thaws, tiny microbes in the ground begin digesting on the organic material underneath, releasing carbon dioxide and methane. Though, scientists have yet to understand what kind of toll global warming has on these microbes.

According to a new study published in the latest issue of the Proceedings of the National Academy of Sciences, researchers are now attempting to answer the question of how microorganisms in the Arctic are affected by the rising temperatures on Earth. Rather than focusing on strictly carbon dioxide, a majority of the study look at the production of methane, a very potent greenhouse gas.

Carbon dioxide is a much more abundant gas; however, methane is much more dangerous. Methane is a very thick gas, and around 25 times more efficient at trapping heat in the atmosphere. Some authors from the study stated their data proved that the thawing permafrost has contributed to 10 percent of worldwide methane emissions. Moreover, projections for temperatures in the Arctic show that an increase of six degrees Celsius in the winter and 11 degrees Celsius in the summer months is very possible by the end of the century. Therefore, learning how methane-producing microbes function when temperatures rise can help scientists make better future predictions about the atmosphere.

microbesThe study found that the microbes in the thawing permafrost are astoundingly good at adapting to different climates and rising temperatures. Thus, the warmer the ground becomes, the more methane they will produce to further threaten the Earth with climate change. The researchers studied the behaviors of microbes living in the oxygen-deprived Arctic peat soil. After getting field samples of the peat soil and the microbes therein, the team put the samples in the incubator. After a temperature change from one to 30 degrees Celsius, the methane production rate from the microbes rose in correlation with the increase in temperature. Mette Marianne Svenning, one of the study’s lead authors, stated they found many different types of microbes that increase their methane production even further at higher temperatures.

The researchers found that methane production from microbes may be increasing even at lower temperatures. Their data shows that methane production at just four degrees Celsius was already one quarter of the production rate at 25 degrees Celsius. Svenning stated the microbes in the Arctic have already adapted to the normal conditions and are already a threat to climate change.

Another important finding they came across involves the factors in decreasing the chemical process that manufacturers methane from what the microbes eat. They found there is a seven degree Celsius chemical process threshold, meaning that some microbes are more dominant with methane production at temperatures about seven degrees Celsius. The more dominant microbes used different methods to produce methane. Therefore, they found that since the total amount of microbes in the soil remained constant, it was the shifts, rather than an increase in relative biomass, that brought on the larger amount of methane production. Kevin Schaefer, a researcher at the National Snow and Ice Data Center at the University of Colorado, stated it is important to understand how the microbes function to figure out how to control organic methane emissions.

Schaefer also explained a greater understanding of the microbes in the Arctic environment can help scientists give better predictions of the different in the amounts of carbon dioxide and methane emissions. Although carbon dioxide is less harmful to the atmosphere, current estimate suggest that it will be over 97 percent of all greenhouse gas emissions from the thawing permafrost.

To further these studies, Svenning says the next step is to start searching for how smaller temperature changes affect the microbes, so scientists can measure minor increases over shorter intervals. Schaefer said it is his opinion, “the most important thing is for humans to slash our carbon output enough in the coming decades to prevent the thawing permafrost from becoming a major problem.” Cutting many sources of man-made, carbon-based pollution could give a good boundary against the onset of global warming. Though, the tiny microbes that produce methane from beneath the permafrost may continue to threaten climate change.

By Alex Lemieux


Science Daily

Washington Post

Earth Sky

Photo by Mike Beauregard – Creativecommons Flickr License

Photo by Mike Beauregard – Creativecommons Flickr License


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