We have been reading about droughts and wildfires in one part of the world, even as there are unseasonal floodings and intense hurricanes elsewhere. The melting of Arctic ice and rising sea levels pose a threat to both animals as well as people living along the coasts.
A recent study shows that melting permafrost in Western Canada is leaking acid and threatening the surrounding environment.
Permafrost is ground containing soil, rock, and minerals and that remains frozen for at least two consecutive years. Two years may not seem like a long time, but most the world's current permafrost was formed more than 11,000 years ago during cold glacial periods. Now, these areas of permafrost are thawing in the northern parts of America, Europe, and Asia due to global warming.
Why Is It A Problem?
As permafrost thaws, the organic matter (such as plant matter) are exposed to microbes. As microbes break down the organic matter, they release greenhouse gases like carbon dioxide and methane.
When greenhouse gases are released into the atmosphere, they trap heat and radiation resulting in an increase in Earth's temperature. This increase in temperature then causes more permafrost to melt, subsequently releasing more greenhouse gases. This process is called a positive feedback loop, in which the effect of a stimulus (melting permafrost releases greenhouse gas emissions) causes an amplification or increase of the initial stimulus (melting of even more permafrost due to warming).
The melting of arctic permafrost poses many risks in itself. As it thaws, permafrost buckle and disrupt roads, buildings, and pipelines. The buckling can even cause trees in forests to tip over due to the instability of the melting foundation. In addition, it poses many environmental consequences such as habitat loss for animals such as polar bears. It is estimated that there are 1,500 billion tons of carbon stored in permafrost- that is twice the amount of carbon that is currently in the atmosphere.
What Is Acid Leakage?
Scientists have been concerned with the release of this massive amount of carbon for a while now. However, these estimations do not even account for the effects of acid leakage.
As the permafrost is thawing, many different minerals are mixed together in meltwater, causing the leakage of sulfuric and carbonic acid. This leakage causes the weathering of the surrounding landscape and rock. Weathering is the breakdown or dissolving of rocks and minerals on the Earth's surface.
Scientists say that this acid leakage could have two effects. If the acid leakage contains sulfuric acid, the resulting weathering will cause the release of even more carbon than initially estimated in the Arctic. However, if the leakage contains carbonic acid, weathering could actually trap more carbon from the atmosphere, lessening the effects of melting permafrost on global warming.
At the moment, scientists are not sure what portion of melting permafrost contains each acid. Regardless, they are concerned with what this possible increase in carbon emissions means for the rate of global warming.
Sources: PRI, Newsweek, IFLScience, arctictoday, arcticportal.org