All the Terrible Things That Will Happen Because of Ocean Acidification

Ocean Acidification is one of the many many many consequences of climate change. For those of you who don’t know, ocean acidification is the phenomenon where pH is reduced in the ocean, causing chemical alterations to occur (Doney, 2009). This is happening as a result of all that Carbon Dioxide (CO2) we keep pumping into our atmosphere. The rate at which we’re producing CO2 is accelerating so rapidly, it’s worsening the effects of ocean acidification. These consequences will affect the ocean carbonate system, biological responses of marine life, and marine food webs. This will cause unprecedented damage, and might be irreversible if we don’t do anything to fix it. 

The ocean’s ability to absorb CO2 from the atmosphere depends on the dissolution of calcium carbonate (CaCO3). Scott Doney’s article Ocean Acidification: The Other CO2 Problem, affirms that CaCO3 is used to form shells and skeletons necessary for the survival of marine organisms such as plankton, coral, algae, and many other invertebrates (Doney, 2009). Corals also use CaCO3 to create ecosystems important to marine biodiversity.

This calcification process has declined in these organisms due to ocean acidification. In a study reported by Scott Doney, two species of coral grown in highly acidic conditions lost their skeletons! This study showed that “coral calcification rates can vary greatly in response to changes in pH…” and that “the fitness of organisms overall would change because of the loss of the protective skeleton.” (Doney, 2009). Translation: ocean acidification results in a whole lot of death to coral reefs.  

Mussels, sea urchins, and crabs are also experiencing decreases in calcification. This is causing reduced fertilization success, developmental rates, larval size (Doney, 2009). 

Analysis of the Great Barrier Reef has shown decreases in calcification rates of 21% from 1988-2003. If we continue “business as usual” CO2 emissions, coral calcification rates could decrease as much as 40% by the end of the century (Doney, 2009). The increased dissolution of CO2 has decreased the dissolution of CaCO3 and its ability to absorb CO2. This reduces the ocean’s overall ability to absorb CO2, accelerating the consequences we are already facing. 

This has also caused a shift in marine ecosystems. Phytoplankton that grow at high CO2 levels are thriving, a little too well. While other phytoplankton species that cannot tolerate such an environment die out, this population explosion will degrade the food quality for zooplankton (Scott, 2009). This combined with the increase in thermal stratification has been linked to decreases in phytoplankton biomass/ productivity around the world. This, along with decreases in calcification, completely changes current food webs. As ocean acidification worsens, organisms will either have to adapt or face extinction. 

Ocean acidification is clearly damaging our marine ecosystems. It’s hampering marine organisms that depend on CaCO3 to build their shells and skeletons. Ocean acidification “impacts processes so fundamental to the overall structure and function of marine ecosystems that any significant changes could have far-reaching consequences for the ocean.” (Scott, 2009). This will cripple millions who depend on the ocean’s resources, and could collapse fishing industries across the world. Although more research is needed, it’s clear to me that ocean acidification is becoming a crisis. We have to act on this, and demand more action on climate change and conservation efforts, before it's too late. But what do you think? Will ocean acidification be as bad, or worse than we predict? How should we protect our marine ecosystems? Let me know in the comments. Reach out to me at gac94@cornell.edu for questions and suggestions for what I should cover next, and I hope to hear from you in the next post!

Pictures:

 

https://www.postandcourier.com/news/ocean-waters-off-southeast-coast-are-acidifying-faster-than-anyone-expected-and-threatening-marine-life/article_b7ca31d8-fdd3-11e6-ba03-9f55adfbac57.html 

 

https://www.worldatlas.com/articles/what-is-ocean-acidification.html 

 
http://acapes.weebly.com/ocean-acidification-lab-report-2.html

Work cited:

• Doney, Scott C, et al. “Ocean Acidification: The Other CO 2 Problem.” Annual Reviews, Jan. 2009, https://www.annualreviews.org/doi/abs/10.1146/annurev.marine.010908.163834.