The effects from the COVID-19 pandemic have resulted in the largest annual decrease in global carbon dioxide (CO2) emissions based on countries with the highest industrial output, including China, the United States, India, and the European Union, as well as the global oil sector [12]. With lockdowns and stay-at-home orders being implemented in the vast majority of the world, the overall production decreased by 8.8% in the first half of 2020 alone [12].
In regards to these emissions, the anthropogenic greenhouse effect – the gradual, incessant warming of the Earth’s surface due to human-related greenhouse gas emissions, including land use change and fossil fuel burning – is oftentimes the first pertinent concern [6]. However, ocean acidification is also a relevant, yet overlooked secondary concern that is directly related to atmospheric CO2 levels. Oceans are a crucial element in offsetting the anthropogenic greenhouse effect; they are natural carbon sinks, or reservoirs, that uptake CO2 in the form of dissolved inorganic carbon (DIC), enable its conversion to dissolved organic carbon (DOC) through chemical processes, and sequester this carbon to the deep ocean where it can persist for thousands of years out of Earth’s atmosphere [1].
Increased anthropogenic CO2 results in increased pressure placed on oceans to absorb more atmospheric CO2 [1]. This ultimately favours a decrease in carbonate ions and a net increase in protons, which decreases the pH of oceans, making them more acidic [8]. Acidifying oceans have cascading effects on aquatic organisms and, eventually as the effects reach higher trophic levels, humans.
Although it is known that CO2 emissions have been altered during the global pandemic,the effects in regards to ocean acidification are largely understudied. This paper evaluates how the effects from COVID-19 have changed ocean acidification trends and, consequently, the impact on aquatic ecosystems. Future approaches and limitations in monitoring ocean acidification and aquatic ecosystem health are also discussed.
Rizvi A., Forsythe M., Steen J., Bhavsar D. & Mardon A. A., 2021. How have reductions in global carbon dioxide emissions during the COVID-19 pandemic influenced aquatic ecosystems through ocean acidification? Academia Letters: 3437. doi: 10.20935/AL3437. Article.
