Part 1: Ocean Acidification

What’s happening in our ocean and how it’s affecting us

Recently, we did a lab in science class where we had to use acid. Before we could even do the lab, we had to put on gloves and goggles, and aprons. Even with all the protective gear on, we were still instructed to carefully move the acid using prongs. Now obviously the ocean isn’t the same thing as hydrochloric acid, but it is slowly creeping down the pH scale towards that way. Because of the burning of fossil fuels and other activities that realize carbon emissions, the ocean has become increasingly acidic, resulting in dangerous conditions. So, how are our everyday habits destroying the marine environment, and what can we do about it

What is Ocean Acidification?

Ocean acidification is defined as the decrease in the pH of Earth’s ocean as a result of increased uptake of CO2. Most of the time when we think about an increase in CO2 levels, we think about their effect on the air. But, oceans actually absorb about 30% of CO2 released into the air. This means that increased carbon emissions mean higher CO2 levels both in the ocean and in the air.

So how do increased CO2 levels in the ocean actually become acidification? While, when CO2 is absorbed into the ocean is causing a series of chemical reactions which result in an increase in hydrogen ions in the ocean. Remember, an increase in hydrogen ions means a more acidic concentration, something we don’t want in the ocean.

What are these chemical reactions that are causing the acidification? First, the CO2 is absorbed into the water where it reacts with water or H2O to form carbonic acid. The carbonic acid will then dissolve to form H+ ions, which are acidic, and bicarbonate, which is a base or more alkaline. Another component of seawater, carbonate, then neutralizes H+ ions.

How CO2 gets incorporated into seawater

Now typically, the reaction above would result in calcium carbonate products, which can then be used by organisms for shell-building. When these organisms die, the shells would be dissolved back into carbonate ions, replenishing the system.

Unfortunately, the increase in CO2 absorbed means that more carbonate ions are needed to neutralize H+ than are being produced, resulting in the increase in acid in the ocean. Because the process of replenishing carbonate ions can take hundreds of years, this means that there are no longer enough carbonate ions in the ocean. And this is how ocean acidification happens.

The Last Period of Ocean Acidification and What it Could Mean for Us😬

The last time the ocean reached levels of acidification similar to today’s levels was about 55 million years ago, during the Paleocene-Eocene Thermal Maximum, aka PETM.

During PETM, there was a major increase in carbon released as methane that resulted in a 5–8 degree Celcius increase in temperature. As a result of this rapid global warming, resulting in a large extinction, specifically in the ocean.

The PETM saw a major spike in carbon emissions leading to mass extinction, and we are creating the same situation millions of years later.

In the early 2000s, a project called Ocean Drilling Program
(ODP) Leg 208 drilled into the pelagic cores, also known as layers of fine sediment found on the ocean floor, from the PETM period. When they did this, they found shocking results. Both above and below the sample from the PETM period was a carbonate-rich, oozy core that was composed of 80–90% carbonate. But, when they got to the PETM sample, it was a hard, dark color clay material with less than 1% carbonate!

So why do we even need carbonate? While many sea animals use carbonate and calcium found in the seawater to create and maintain their shells and skeletons.

When there is an increase in H+ ions because of increased CO2 absorption, that means that more carbonate ions are binding to H+ ions and are no longer available for organisms to use.

This results in fewer calcifying organisms since they no longer can build their shells. Sometimes the decrease in carbonate in the seawater can even make it so the shells of these organisms dissolve! 🤯

From coral to crabs, ocean acidification is very dangerous to calcifying organisms

Since many calcifying organisms, such as pteropod, are important in food webs, this means that many animals from shrill to killer whales are at major risk for extinction.

Now, even though our current situation isn’t the exact same as the situation during the PETM period, it is similar enough that we have some idea of the danger we are in. The rapid increase in pH levels in the ocean has the potential to lead to mass extinction.

It took the Earth millions of years to recover from the PETM period, so the current ocean acidification we’re experiencing will most likely be devastating and extremely damaging to all parts of the Earth, even the land-dwelling mammals.

How Will This Affect Humans?

Malnutrition

One of the biggest impacts ocean acidification will have on humans involves are health and malnutrition. Right now, 3 billion people across the world rely on seafood as their main source of nutrition.

Ocean acidification means that important animals in the marine food webs, such as the pteropod, go extinct, which means important organisms to feed humans, such as fish, began to disappear too. On top of that, 50% of animals tested showed a negative response to ocean acidification.

Even if marine organisms survive, many of them have reduced nutritional value. In a study done on cultured whelk species, ocean acidification leads to a major reduction in the species concentration of lipids and proteins. This was especially concerning because lipids have many benefits to overall human health, such as the reduced risk of heart disease and fat-soluble vitamins.

In a world where finding nutritious food is already a struggle for many people, the loss of a major source of food will be a massive issue!

With their shells, oysters and similar organisms are particularly at risk for the effects of ocean acidification.

Respiratory Problems

If the loss of food isn’t enough to concern you, ocean acidification can lead to many very serious respiratory issues as well. You might have heard of the Flordia red algae blooms, but did you know that ocean acidification can actually result in an increase in these blooms.

These algae bloom release brevetoxins, which can result in irritation of the upper respiratory system as these toxins are inhaled. This can result in potential long-term and short-term effects that can be very dangerous to humans.

Flordia’s Red Tide

Loss of Natural Spaces and Economic Effects

Right now, about 300 million people live in areas near the ocean. A major part of their lives revolves around the sea, whether for recreation or food. Most of these people revolve around fisheries or similar ocean-based activities for unemployment.

Ocean acidification will lead to a major collapse of fishing-based economies, putting millions of people into unemployment, which could lead to a massive mental health crisis.

On top of that, fun activities around the ocean may no longer become safe. Recently, ocean acidification has to lead many new dangerous species to migrate, such as the Box jellyfish to Australia. This means people can no longer participate in their normal activies.

In case you don’t remember, in the early 2000s there was a major collapse of the $117 million West Coast shellfish industry. Unfortunately, this was one of the first widespread effects of ocean acidification seen. If ocean acidification keeps getting worse, this could happen across the globe, putting millions of people out of jobs and without food.

Box jellyfish stings are extremely painful and can even be deadly.

So…What Can We Do About It?

Ocean acidification will be devastating to our plants and to us as humans, but is there anything we can do to stop it? For one thing, by investing in monitoring tools, we can help pinpoint specific locations of concerns and target them with relief measures.

Another tool for trying to slow and stop ocean acidification is reducing overall carbon emissions. Recently, many automotive companies have been producing electric cars, such as Volvo and GM, which will help us reach our goal of reducing our carbon emissions. Calling for energy plants to try and reduce their carbon emissions is also very important in reaching our overall goal.

Tools such as the one shown above are used to monitor ocean acidification and target specific regions at high risk.

Hopefully, we will be able to stop ocean acidification before it is too late, but it all depends on how much effort is put into stopping increasing carbon emissions and global warming.

If You Want to Learn More…

Understanding Ocean Acidification

Ocean acidification and human health

What is Ocean Acidification?

Introduction

If you’re still not sure about the impact of global warming, or you want to continue to learn more, follow me to check out the rest of the climate change series!

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