The Effects of Ocean Acidification on Corals

Coral reefs are often the “rainforests of the sea”. They are one of the most biodiverse habitats in the world and support about 25% of our ocean creatures. They also serve as home for many marine life populations and are very important to our ocean habitats.  Corals are a food source for many marine species and are threatened by climate change and ocean acidification. As carbon dioxide in the ocean increases, ocean pH decreases or becomes more acidic. This is called ocean acidification.  Corals are estimated to grow only about an inch a year. Consequently, they are being destroyed at a much faster rate than they are growing, causing devastating effects on our oceans’ ecosystems.

Hard corals are the reef building corals and have skeletons composed of calcium carbonate, the same material in the shells of clams, snails and oysters.  Corals must have access to calcium in seawater for building their skeletons and growth.  However, ocean acidification is causing the pH in our oceans to change and corals are having a hard time building their skeletons.  Coral colonies are becoming more brittle and unable to grow due to the lower pH.  Corals are already being affected by climate change’s raising of ocean temperatures and they become bleached and more susceptible to diseases.  Nutrient and chemical pollution from oceans and rivers is also making coral reefs less habitable for many marine species.  Check out this video from PBS on the effects of ocean acidification on coral reefs.

The ocean is already about 30% more acidic than in previous years and if nothing is done to reduce carbon dioxide emissions into the atmosphere, ocean acidification will increase causing more and more corals to be damaged or destroyed. Scientists estimate, by the year 2100, the ocean pH will lower to under 7.8, a level which corals will be unable to grow and support the species needing them.  Using less energy and recycling are simple ways you can make a difference in the health of our oceans and help prevent future ocean acidification.  Check out this video for more on ocean acidification. 

Written By: Stefanie Schmidt

Edited By: Bob Stone




Good infographic to effects on corals:


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