Since last year, attention to climate change has greatly increased. Greta Thunberg, a sixteen-year-old from Sweden, gave a moving speech at the UN Climate Action Summit and highlighted the potential catastrophic effects of neglecting climate change. Her activism led millions to strike and protest for change, unfortunately, this unprecedented attention and activism was not distributed fairly to other significant environmental issues. There is another pressing matter that may be as catastrophic as global warming: ocean acidification.
Ocean Acidification explained with a bit of chemistry
Parallel to rising sea levels and temperature of the oceans, the average acidity in the oceans is also surging in an unprecedented manner. Interestingly enough, the main culprit of ocean acidification is carbon dioxide, a greenhouse gas that makes the Earth warmer every year. Since the industrial revolution, the dramatic increase of carbon dioxide has not only stayed in the atmosphere (leading to a greenhouse effect), but almost 30 to 40 percent of carbon dioxide dissolved into the oceans. This increased carbon dioxide is a direct cause of rising acidity in the oceans.
The pH scale is a logarithmic scale - each step in the pH scale is a factor of 10-, which means 0.1 pH unit decrease since the start of the industrial revolution represents a 30% increase of the acidity.
Although there are some chemical reactions involved in a process of carbon dioxide increasing acidity, it would seem much easier by understanding the whole process as the dissolving of hydrogen ions. When carbon dioxide(CO2) is absorbed by the seawater(H2O), a substance called carbonic acid(H2CO3) is created. Soon, this weak acid breaks into hydrogen ions(H+) and bicarbonate ions(HCO3-), thus increasing the dissolved hydrogen ions in the water and decreasing the pH.
The impact of ocean acidification reach humanity
Indisputably, increased hydrogen ions in the oceans affect the marine ecosystem and diversity. The entire marine species are generally affected in terms of drops in metabolic rate and immune response. Particularly, species with hard shells and skeletons such as crabs and oysters are extremely vulnerable to ocean acidification as an increased amount of hydrogen ions reduces the available amount of calcium carbonate(CaCO3), which is the source of maintaining these shells.
Considering oceans as a place where all forms of life began, it is nearly impossible to predict the exact impact of ocean acidification on the entire ecosystem. Moreover, research on ocean acidification on a global scale is lacking compared to research on climate change. Yet, the affects are already felt in many aquaculture and fishing industries as they are threatened around the globe. For example, the National Oceanic and Atmospheric Administration(NOAA) published a research report, claiming that “Alaska waters are especially vulnerable to OA(ocean acidification)”. It is expected that Alaska’s fishing industry and tourism will be significantly harmed by ocean acidification, and communities that rely on fishing and subsistence farming directly faced the biggest threat. Also, it is more than mere numbers. The various marine ecosystems have brought a unique culture and identity in these particular regions.
Any solutions? What can we do about it?
So far, ocean acidification seems a very complicated process that disrupts the marine ecosystem in so many coastal regions simultaneously. Still, a mystery veiled by unknown impacts, ocean acidification will not simply disappear in our lifetime.
Then, are there any ways we can act upon it? Yes, we absolutely do. As the main cause of ocean acidification is the same as climate change, the methods to slow down climate change can be identically applied. Conserving energy generated from fossil fuels such as considering alternative energy options or choosing the most energy-efficient appliances would be exemplary. Most importantly, the attention towards these environmental issues and personal efforts are the most important. Our attention is what lets researchers focus on ocean acidification and leads to slow-paced but sturdy civil education about the issue.
More resources available for ocean acidification
https://www.pmel.noaa.gov
https://ocean.si.edu