The National Ocean and Atmospheric Administration have estimated that since the 1850s, our world’s oceans have become 30% more acidic, a rate ten times faster than any known experienced change in maritime history in the last 55 million years. The United Nations Educational, Scientific, and Cultural Organization (or UNESCO) expects that by 2100 there will be a doubling of acidity in our oceans. These changes are having enormous ecological consequences and threatening billions of dollars in damage to global markets. This process is called ocean acidification. To understand its impact on our environment and our economy, we need to understand how and why the sea is getting more acidic.
Around 25% of carbon dioxide in the atmosphere dissolves into the ocean and chemically bonds with the surrounding calcium to form calcium carbonate, a crucial building block for the essential shells of marine organisms such as coral, oysters, and species of plankton. Carbon dioxide dissolving into the ocean is a good thing for these marine organisms that need calcium carbonate shells. However, too much carbon dioxide dissolving into the sea makes the sea more acidic.
With an excess of carbon dioxide entering our oceans, not all will bond with calcium—some carbon dioxide molecules bond with the surrounding water molecules. Carbon dioxide and water bond to produce carbonic acid. As cycles of carbonic acid production repeat, the ocean becomes more acidic.
The ocean can also get more acidic when calcium carbonate chemically bonds with dissolved carbon dioxide and surrounding water molecules, producing calcium and bicarbonate. Hence, calcium carbonate is not used in the making of the much-needed shells of marine organisms.
Now that we understand the causes of ocean acidification let us turn our attention to the severity of the issue.
Besides stealing calcium carbonate from the marine organisms that need it, increased acidity can dissolve the shells and skeletons of marine organisms. This means that marine organisms have to spend more energy strengthening and repairing their shells and skeletons. It’s also important to note that rising temperatures accelerate the dissolution of the shells and skeletons of marine organisms and coral — the Intergovernmental Panel of Climate Change found that we could lose 99% of the world’s warm-water coral reefs if global temperatures rise above pre-industrial levels by 2°C.
The increases in world temperatures, paired with acidification, are already having severe impacts on our oceans. In addition, there are also vast consequences of ocean acidification that are leading to significant economic effects, such as the potential for multi-billion-dollar losses. The same UNESCO study that found that the ocean’s acidic rate would double by 2100 also found that the costs of marine organisms struggling to form or repair their shells could amount to approximately $130 billion a year. Alongside making it harder for shellfish to create, rebuild, and strengthen shells, there has also been a rapid increase in toxic algae blooms. Not only do shellfish have a more difficult time fighting off the effects of toxic algae blooms, but increased warmer temperatures and higher CO2 levels result in increases in both the toxicity and frequency of toxic algae blooms. The toxic algae produce a dangerous neurotoxin called domoic acid, which builds up in the bodies of shellfish and poses significant health risks to humans who consume these shellfish. Consequently, many fisheries have been forced to shut down.
Ocean acidification also poses a severe threat to Singapore and Southeast Asia, including damage to coral reefs that are detrimental to the millions of people who depend on them for subsistence.
So what can we do? The International Union for the Conservation of Nature suggests changing our diet with low meat intake to reduce overall meat demand. After all, raising and breeding livestock is a significant source of greenhouse gases. We also can eat fewer mussels and oysters as there is an increasing shortage of those species due to the rapidly increasing threats of ocean acidification. We can also collectively lobby our MPs and the government to embrace new solutions such as installing climate capture technologies and leveraging nature-based solutions. For example, according to the West Coast Ocean Acidification and Hypoxia Science Panel, growing sea plants, such as seagrass meadows, in our oceans can effectively give corals an 18% boost in growth.
Right now, we are on a path. A path that is killing marine organisms. A path that will destroy our beautiful precious coral reefs. A path that is a threat to local and global ecological and economic systems. Fortunately, we have the means for change. We can unite and organize to call for solutions, and turn the tide on ocean acidification, together.
Jeenaev Shah is a 14-year-old student at UWCSEA East Campus, passionate about ending the environmental issues that are defining our time. He is part of his school’s Service Executive Committee, a group of student leaders that organizes many large-scale community service events at his school. He was also featured in Plastic-Lite’s 2019 National Day Campaign. In his spare time, he enjoys writing, reading, and cycling.