Ocean Acidification: A Catalyst For Pollution?

Ocean acidification is a pressing issue that poses a significant threat to the world's oceans, estuaries, and waterways. It is caused primarily by carbon pollution from the burning of fossil fuels, which leads to an increase in the acidity of seawater. This phenomenon has far-reaching consequences for marine life and ecosystems, including shellfish, corals, and other organisms that rely on calcium carbonate structures for survival. The rising concentration of carbon dioxide in the atmosphere is driving up ocean surface temperatures, and the absorption of excess carbon dioxide by the oceans is causing chemical changes that make the water more acidic. This process of ocean acidification is having detrimental effects on marine life and the industries that depend on it.

Fossil fuels and carbon pollution

Fossil fuels are formed from the decomposition of carbon-based organisms that died millions of years ago. They are extracted and burned for energy, and they create carbon-rich deposits. There are three types of fossil fuel: coal, oil, and gas.

The burning of fossil fuels releases large amounts of carbon dioxide, a greenhouse gas, into the atmosphere. In 2019, fossil fuels accounted for 74% of US greenhouse gas emissions, and nearly 25% of emissions in the US came from fossil fuels extracted from public lands. Fossil fuel companies remain huge polluters, and in 2019, BP spent millions on an advertising campaign about its low-carbon energy and cleaner natural gas. However, in reality, more than 96% of BP's annual expenditure is still on oil and gas.

The carbon dioxide released from burning fossil fuels is a major cause of ocean acidification. The carbon dioxide is absorbed by the ocean, and this changes the pH of the seawater, making it more acidic. The average acidity of seawater has increased by 30% since the Industrial Revolution, and the oceans have absorbed around one-third of all carbon dioxide released from fossil fuels. This increase in acidity has a detrimental impact on marine life, particularly shellfish, and coral reefs.

To combat this issue, there have been calls to advance the global transition to clean energy, with stronger pollution regulations for power plants, and improved fuel-economy standards for vehicles.

Impact on marine life

Ocean acidification is a global threat to marine life. It is caused by carbon pollution from the burning of fossil fuels, which leads to an increase in carbon dioxide (CO2) in the atmosphere. This excess CO2 is absorbed by the oceans, resulting in a decrease in pH and greater acidity. This change in ocean chemistry has significant impacts on marine ecosystems, particularly those that rely on carbonate-based shells and skeletons.

One of the most well-known effects of ocean acidification is its impact on shellfish, such as oysters, clams, and lobsters. The increased acidity of seawater makes it difficult for these organisms to build and maintain their shells, leading to a condition similar to osteoporosis in humans. Laboratory studies have shown that even small increases in acidity can slow the growth of shells and, in more severe conditions, cause shells to dissolve faster than they can form. This has significant implications for commercially valuable shellfish industries, which are already facing threats from ocean acidification.

Coral reefs are also highly vulnerable to ocean acidification. Reef-building corals craft their homes from calcium carbonate, providing habitat for many marine species. However, the increased acidity of seawater weakens these structures, making it difficult for corals to build and maintain their reefs. This has already led to a decline in living corals in the Great Barrier Reef, reducing habitat for fish and decreasing the resilience of the entire reef system. Cold-water reefs in waters off of Scotland, Norway, and the Caribbean are also facing similar threats.

In addition to shellfish and corals, other marine species are also affected by ocean acidification. Marine fish and invertebrates, for example, rely on their sense of smell during their early larval stages to avoid predators. However, in more acidic conditions, fish larvae lose their ability to smell, making them more susceptible to predation. This increased vulnerability means that while organisms may be able to reproduce, their offspring may not reach adulthood, disrupting the balance of marine ecosystems.

The rapid rate of ocean acidification also poses a significant challenge to marine life. Marine organisms have evolved over millions of years in an ocean with a relatively stable pH. The current rate of change does not give them enough time to adapt, and while some species may be able to adapt to more extreme conditions, many will suffer, and there is a likelihood of extinctions.

Ocean acidification and warming

Ocean acidification is a direct consequence of the burning of fossil fuels and the resulting carbon pollution. The oceans absorb CO2 from the atmosphere, which reacts with seawater to form carbonic acid. This carbonic acid then dissociates, producing bicarbonate ions and hydrogen ions. The increased concentration of hydrogen ions and a reduction in carbonate ions result in higher acidity and a lower pH. This process is known as ocean acidification.

Since the industrial revolution, the concentration of carbon dioxide in the atmosphere has increased due to human activities, such as burning fossil fuels and deforestation. As a result, the oceans have absorbed a significant portion of this CO2, estimated to be around one-third of all CO2 released from fossil fuels. This has led to a 30% increase in the acidity of seawater.

The combination of ocean acidification and warming poses a significant threat to marine life, particularly species that build their shells and skeletons from calcium carbonate, such as clams, mussels, crabs, phytoplankton, and corals. Acidification reduces the availability of carbonate ions, making it difficult for these organisms to build and maintain their shells and skeletons. It also hinders the ability of corals to recover from bleaching events, further endangering coral reefs already impacted by warming waters.

To address ocean acidification and warming, it is crucial to transition to clean energy, implement pollution regulations, and enhance the resilience of carbon sinks through conservation efforts. Additionally, policymakers must recognize the economic impact of these changes and introduce climate action plans to increase investments in monitoring, forecasting, and mitigation.

Impact on coral and shellfish

Ocean acidification is a severe ecological issue that poses a threat to the world's oceans, estuaries, and waterways. It is caused by the absorption of carbon dioxide (CO2) from the atmosphere into the ocean, resulting in increased acidity and a lower pH level. This process has been primarily driven by carbon pollution from the burning of fossil fuels and has led to significant changes in the chemical composition of seawater. The impact of ocean acidification on coral and shellfish has been particularly concerning, and it has had far-reaching consequences for marine ecosystems and human communities that depend on them.

Coral reefs, which are rich in biodiversity and provide habitats for numerous marine species, have been severely affected by ocean acidification. The increased acidity makes it difficult for corals to build and maintain their calcium carbonate structures. As a result, coral reefs are weakening, and their ability to reproduce is hampered. This has led to a decline in living corals, particularly in the Great Barrier Reef, where coral coverage has halved over the past three decades. This reduction in coral coverage has had cascading effects, decreasing fish habitats and the overall resilience of the reef systems.

Similarly, shellfish, including commercially valuable oysters, clams, and scallops, have been impacted by ocean acidification. The acidic conditions make it challenging for these organisms to extract the calcium carbonate necessary for shell formation. As a result, shells become thinner and more brittle, resembling osteoporosis in humans. This phenomenon has led to increased mortality rates among shellfish, with oyster larvae on the northwest coast dying off by the billions. The impact on shellfish has the potential to disrupt marine food chains and the economies of communities that rely on shellfish harvesting and fisheries.

The effects of ocean acidification on coral and shellfish have far-reaching implications for marine ecosystems and human communities alike. Coral reefs provide essential habitats for a diverse range of marine life, and their decline can lead to a loss of biodiversity and ecosystem services. Additionally, shellfish are a crucial source of food and income for many people, and their decline can have economic and social repercussions, particularly in regions heavily dependent on fisheries. Furthermore, the disruption of marine food chains can have unforeseen consequences for species higher up the food chain, including humans, who may experience altered seafood supplies and potential health risks from consuming contaminated shellfish.

Addressing ocean acidification requires a global transition to clean energy and the implementation of policies to mitigate carbon pollution. By reducing carbon emissions and enhancing the resilience of ecosystems, such as through conservation initiatives, we can help to safeguard vulnerable marine life, maintain the balance of marine ecosystems, and protect the livelihoods of those who depend on the oceans for sustenance and economic stability.

The future of ocean acidification

Ocean acidification is a pressing issue that poses a significant threat to the world's oceans, estuaries, and waterways. The future of this phenomenon is closely tied to human activities and our ability to address the root causes. Here is an outlook on the future of ocean acidification:

The Driving Factors

Ocean acidification is primarily driven by carbon pollution from the burning of fossil fuels. Since the Industrial Revolution, human activities have released unprecedented amounts of carbon dioxide into the atmosphere, and the oceans have absorbed a significant portion of these emissions, estimated to be around a quarter annually. Deforestation is another contributing factor, as clearing or burning forests releases stored carbon into the air.

Projected Trends

The current rate of ocean acidification is alarming. Studies suggest that it is occurring about ten times faster today than it did 55 million years ago, when a mass extinction of marine species occurred. If left unchecked, ocean acidification is projected to intensify in the coming decades. By 2100, global average ocean pH levels could drop to around 7.67, representing a fivefold increase in acidification compared to pre-industrial times.

Impact on Marine Life

The increasing acidity of seawater has severe implications for marine life, particularly shellfish and other calcifying organisms. The process of ocean acidification makes it more challenging for these organisms to build and maintain their shells and skeletons, which are essential for their survival. This, in turn, can disrupt the entire marine food chain, affecting species that rely on these organisms for food, including fish, birds, and marine mammals.

Addressing the Issue

Adaptation and Resilience

As we navigate the future of ocean acidification, building resilience in vulnerable industries, such as fisheries and shellfish farming, becomes crucial. This includes diversifying income sources, adapting farming practices, and providing resources to communities heavily impacted by ocean acidification.

In summary, the future of ocean acidification is a pressing concern that demands immediate and decisive action. By reducing carbon emissions, transitioning to clean energy, and implementing conservation measures, we can help mitigate the worst effects of ocean acidification and safeguard the health of our oceans and the countless species that depend on them.

Frequently asked questions