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Ocean Acidification 101: Our Actions Cause Ocean pH to Drop And Its Organisms Are The Casualties

Increased CO2 Presence In Our Oceans Has An Uncountable Amount Of Adverse Effects.

By Richard Xu

A Pteropod, one of many organisms that relies on carbonate in the water to build its shell. Photo Credit

Our oceans which cover 70% of the planet’s surface are actually responsible for absorbing around 30% of human CO2 emissions. As the biggest carbon sink on our planet, there are ramifications to the increased presence of CO2 entering our oceans.

Chemically speaking, dissolved CO2 in our oceans eventually becomes carbonic acid or H2CO3; this releases a hydrogen ion (highlighted below) into the water column:

H2O + CO2 ⇒ H2CO3 ⇒ 2H+(aq) + CO3=(aq)

Due to this, the water chemistry becomes more acidic. For context, pH or potential of hydrogen, is measured by the concentration of hydrogen ions in a medium. The higher the amount of hydrogen ions, the more acidic a substance will be and vice versa. The previously mentioned released hydrogen ions can combine with carbonate ions to form bicarbonate (highlighted):

H+(aq) + CO3=(aq) ⇒ HCO3-(aq)

The issue is that carbonate is a primary material used by marine calcifiers to build and maintain their shells & skeletons; the decreasing presence of it leads to a thinner and potentially non-present calcium structure.

The chemical process of ocean acidification. Photo Credit

Not only does this contribute to declining coral reefs by breaking down their structure — check out also our blog on the other issues our coral reefs face such as coral bleaching — but multiple organisms in the ocean food chain have become affected, which has dire effects. For example, decreases in the quantity of pteropods, foraminiferans, and coccoliths would lead organisms that consume them such as small fish and krill to find other food sources. Organisms lower in the food chain becoming less abundant means that there are less resources for those at the top which inevitably also affects us humans.

There are also some species that simply cannot adapt at the rate that our oceans are becoming acidic. For example, clams which typically use their shells for protection might face issues with more brittle shells. This would make it possible for predators to overindulge in clams which decimates clam populations and bolsters predator populations causing a predator-prey imbalance and ecosystem chaos.

The worst part of this all is that failure to protect our oceans from global warming could actually increase the rate at which our planet heats up. Phytoplankton, which suffer from the increasing acidity in our oceans, produce dimethyl sulfide or DMS (fun fact this is what is responsible for that “ocean smell”). The great thing about DMS is that it is a large quantity of sulfur that enters the atmosphere which stimulates cloud formation which then helps cool the earth by reflecting light back into space. Unfortunately, the rate at which these DMS producing phytoplankton die off increases as global warming continues. Another unfortunate outcome is that phytoplankton in general can also photosynthesize, so losing more of them negatively impacts the conversion of CO2 to oxygen.

Therefore minimizing our carbon footprint and decreasing the anthropogenic CO2 emissions is our nagging moral responsibility now more than ever. Our overreliance on big Oil & Gas industry players and the pervasive use of their fossil fuel-derived plastics is a major catalyst of global warming and ocean acidification. Cutting back on CO2 emissions will increase the amount of carbonate present in the water column allowing aquatic species to be able to gradually adjust to the ever changing conditions.

How can Nikira Labs assist? At Nikira Labs, we offer multiple state-of-the art greenhouse gas (GHG) analyzers to monitor GHG emissions, including CO2, in real-time. With our technology, regulated gas emissions can be constantly measured and verified against their compliant limits, and exceedances can be detected and flagged immediately for corrective actions. The latter is an essential step in fighting global warming and providing real-time alerts for operators to intervene, repair, and test the integrity of the fix.


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