How Ocean Acidification Is Disrupting Marine Life
Ocean acidification is changing the chemistry of our seas, weakening coral reefs, harming shellfish, and altering marine ecosystems. Here’s what’s happening and what divers should know.
PRESERVING OUR GREAT LAKES AND OCEANS
How Ocean Acidification Is Disrupting Marine Life
What Is Ocean Acidification?
When carbon dioxide (CO₂) from the atmosphere dissolves into seawater, it reacts to form carbonic acid, lowering the water’s pH. Since the Industrial Revolution, the ocean’s surface pH has fallen from about 8.2 to 8.1 — a roughly 30 percent increase in acidity. Scientists warn this process will continue if CO₂ emissions aren’t reduced.
How It Impacts Marine Ecosystems
Coral Reefs Are Losing Their Strength
Corals rely on calcium carbonate to build their skeletons, but more acidic water makes this harder. As a result, reefs grow more slowly and become fragile. Combined with warming-driven bleaching, this could lead to widespread reef collapse by the end of the century if emissions continue unchecked.
Shellfish and Other Calcifiers Struggle
Organisms like oysters, mussels, and sea urchins face the same challenge as corals — their shells dissolve more easily and larvae often fail to develop. Shellfish farms in the Pacific Northwest have already seen significant losses linked to more acidic upwelling events.
Fish Behavior Is Changing
Acidification doesn’t just affect shells; it also impacts fish physiology and behavior. Some studies show reef fish exposed to lower pH levels are more likely to lose their ability to detect predators or navigate safely, disrupting entire food webs.
What Divers Should Know and Do
Be Reef-Safe: Dive carefully to avoid breaking already weakened coral skeletons.
Support Science & Restoration: Programs like NOAA’s Coral Reef Conservation Program and citizen-science initiatives such as CoralWatch rely on diver observations.
Advocate for Emission Reductions: Ocean acidification is directly tied to CO₂ levels. Supporting renewable energy policies and climate-conscious practices benefits marine life.
Choose Responsible Operators: Many dive shops partner with NGOs or participate in reef restoration; supporting these operators amplifies your impact.
Ocean acidification may feel invisible beneath the waves, but its fingerprints are everywhere — from fragile reefs to empty oyster beds. As divers, understanding the issue helps us become better stewards of the underwater world.
Happy and safe diving,
The ScubaBlast Team
National Oceanic and Atmospheric Administration. (2023). What is ocean acidification? Retrieved from https://oceanservice.noaa.gov/facts/acidification.html
United Nations Environment Programme. (2022). The impacts of ocean acidification on marine biodiversity. Retrieved from https://www.unep.org/resources/report/impacts-ocean-acidification
Smithsonian Ocean Portal. (2024). Ocean acidification and marine life. Retrieved from https://ocean.si.edu/ocean-life/ocean-acidification
Intergovernmental Panel on Climate Change. (2023). Special report on the ocean and cryosphere. Retrieved from https://www.ipcc.ch/srocc/