Global Warming’s Evil Twin: How Ocean Acidification Has an Affect On Marine Life

If someone were to talk about climate change or global warming, most people’s heads would immediately be filled with images of melting glaciers, rising sea levels, and blistering heat waves. Now, while these are all very important aspects of climate change, there is something else that is arguably worse than all of these examples. Lurking beneath the waves is a quieter, more insidious threat—ocean acidification, often called global warming’s evil twin. And just like its better-known sibling, its impact reaches far beyond what meets the eye.

What is Ocean Acidification?

Ocean Acidification is defined as the decrease in the ocean’s PH levels, caused by the absorption of Co2. This means that as more carbon dioxide enters, the ocean temperatures rise significantly, causing a threat to both marine animals and humans. Over the past 200 years, the world’s oceans have absorbed more that 150 billion metric tons of Co2 solely emitted by human activity. I’ll write that again. The world's oceans have absorbed 150 billion metric tons of Co2 solely emitted by HUMAN ACTIVITY. Wow.

Source: EncounterEdu

How Human Activity Fuels Ocean Acidification

The primary cause of ocean acidification is the rising concentration of carbon dioxide in the atmosphere. This increase is largely due to the burning of fossil fuels like coal, oil, and natural gas. As humans continue to rely on these energy sources, more Co2 is released into the air. The oceans act as a natural buffer by absorbing some of this excess carbon—about one-third of all human-related carbon emissions since the 1700s. While this helps reduce the greenhouse effect in the atmosphere, it comes at a cost: when Co2 dissolves in seawater, it triggers chemical reactions that lower the ocean’s pH, making it more acidic. 

Simple Causes, Hard-Hitting Effects Widespread Effects of Ocean Acidification

Ocean acidification is already reshaping marine ecosystems and putting coastal economies at risk, especially in areas that rely heavily on fisheries and shellfish.

 Hardest-Hit Regions and Industries

• The U.S. shellfish industry, worth over $1 billion, is vulnerable in regions like the Pacific Northwest, Chesapeake Bay, Long Island Sound, and the Gulf of Mexico. Acidified waters reduce shell-building ability in clams, oysters, and scallops.

• Alaska’s fisheries, responsible for nearly 60% of the U.S. commercial catch and over 100,000 jobs, face growing risks. Cold waters absorb more CO₂, making them more acidic and harmful to marine life.

• Coral reefs are also deteriorating worldwide. Coral structures are weakening in places like the Caribbean, the Great Barrier Reef (which has lost 50% of its coral over 30 years), and cold-water reefs near Scotland and Norway.

• Remote regions such as Patagonia and the Antarctic are experiencing severe effects. In the Antarctic, highly acidic waters are already dissolving the shells of small marine organisms, disrupting entire food webs from the bottom up.

 Marine Life at Risk

• Species that build shells or skeletons from calcium carbonate—such as oysters, mussels, corals, sea urchins, and tiny pteropods—are particularly vulnerable. Acidification limits their ability to form and maintain these structures.

• The stress of more acidic waters forces animals to spend more energy just to survive, leaving less for growth and reproduction. In extreme cases, some may even begin dissolving parts of their own shells to maintain internal balance.

• Larvae are especially sensitive. Oyster and sea urchin larvae may fail to develop properly, while fish larvae can lose their ability to detect predators. This can lower survival rates and threaten future populations.

Source: IAEA

Conclusion:

Ocean acidification may be invisible, but its consequences are not. From coral reefs to shellfish to the global food chain, the ripple effects are already being felt. Protecting our oceans means reducing carbon emissions today—for the sake of marine life, coastal communities, and future generations.

Sources:

• NOAA Fisheries. “Understanding Ocean Acidification.” NOAA Fisheries, U.S. Department of Commerce, www.fisheries.noaa.gov/insight/understanding-ocean-acidification. 

• U.S. Environmental Protection Agency. “Effects of Ocean and Coastal Acidification on Marine Life.” EPA www.epa.gov/ocean-acidification/effects-ocean-and-coastal-acidification-marine-life

Next Time…The Role of Soil Health in Fighting Climate Change