How Does Ocean Acidification Affect the Economy? The Hidden Costs

how does ocean acidification affect the economy

The vast ocean, often viewed as a boundless resource, is facing a silent threat: acidification. Driven by rising atmospheric carbon dioxide, the ocean’s chemistry is subtly shifting, becoming increasingly acidic. While the consequences for marine life are well-documented, the ripple effects on our economy deserve urgent attention.

In this article, we will delve into the ways ocean acidification affects the economy, focusing on two key economic risks. Additionally, we will discuss potential solutions to mitigate these risks.

Background information: Ocean Acidification at a Glance: Ocean Acidification Infographic

effects of ocean acidification on economy summary

1. Decline in Fisheries

Ocean acidification profoundly impacts fisheries, posing severe risks to food security and economic stability. This section delves into the details:

Shellfish Vulnerability: Acidic waters inhibit the ability of shellfish like oysters, mussels, and clams to build protective shells, leading to a decline in shellfish populations. This not only impacts the seafood industry but also threatens a critical source of protein for millions worldwide. Other seafood species, like salmon, are also impacted.

Coral Reefs at Risk: Coral reefs, vital ecosystems, serve as nurseries for marine species, attracting both tourists and fishermen. As ocean acidification deteriorates coral health, it affects fisheries and the marine food chain as a whole, jeopardizing food security and economic livelihoods.

Marine Food Chain Disruption: Ocean acidification impacts microorganisms at the base of the food chain, which has far-reaching impacts, including cascading effects on fisheries as predator-prey relationships shift and fish populations are affected.

Global Consequences: The economic repercussions ripple across the globe. For instance, the Pacific Northwest of the United States, heavily reliant on shellfish aquaculture, is already experiencing significant financial losses due to declining shellfish yields.

Studies estimate global losses in shellfish harvest could reach $480 million annually by the end of the century.

2. Impacts on Tourism

The tourism sector in coastal regions is susceptible to the pervasive effects of ocean acidification, further undermining economic stability:

Declining Attractiveness: Iconic coastal destinations, known for their pristine waters and vibrant marine life, are losing their appeal as ocean acidification damages coral reefs and disrupts underwater ecosystems.

Revenue Reduction: Tourism-related businesses, including hotels, restaurants, and tour operators, suffer from reduced revenues as visitors seek alternative destinations. This results in job losses and economic hardship in affected communities.

No More Wildlife Tours: Coral reefs, once vibrant and full of life, are now threatened, leading to a reduction in biodiversity-related tours. Tourists are increasingly looking for alternative destinations, leaving a lasting impact on the economic sustainability of coastal regions.

Other Effects of Ocean Acidification on the Economy

While a decline in fisheries and tourism revenue are the two key economic risks posed by ocean acidification, acidification is having other major impacts as well, many of which have economic consequences.

Reduced Food Security

Ocean acidification also has a direct bearing on global food security, particularly for communities heavily dependent on seafood:

Nutrient Disruption: Acidic oceans disrupt nutrient availability for marine life. This can lead to altered marine food webs, affecting the abundance and distribution of fish species that are vital for global food security.

Decreased Harvests: Diminished fisheries due to ocean acidification translate to decreased seafood harvests, which can strain the availability of affordable and nutritious protein sources for vulnerable populations.

Infrastructure Vulnerability

Ocean acidification has indirect consequences for infrastructure, as coastal communities face heightened risks from rising sea levels and extreme weather events:

Coastal Erosion: Weakened coral reefs and the degradation of coastal ecosystems due to ocean acidification contribute to coastal erosion, putting infrastructure such as roads, buildings, and utilities at risk. While less visible, acidified seawater can even corrode coastal infrastructure like docks, piers, and seawalls. This increases maintenance costs and can eventually lead to structural damage, impacting ports, transportation, and coastal communities.

Increased Maintenance Costs: Infrastructure in coastal areas must contend with more frequent and severe damage, increasing maintenance costs for governments and businesses.

Solutions to Economic Effects of Ocean Acidification

Addressing both the direct and indirect economic risks of ocean acidification requires a holistic approach:

Reducing Carbon Emissions: Mitigating the root cause of ocean acidification involves reducing carbon emissions. Transitioning to renewable energy sources, enhancing energy efficiency, and promoting sustainable transportation are key steps. New projects are also working to remove carbon dioxide from the ocean.

Sustainable Practices: Implementing sustainable fishing practices, such as catch limits and protected marine areas, can help preserve fish populations and protect the livelihoods of fishermen.

Coral Reef Restoration: Investing in coral reef restoration efforts can aid in revitalizing tourism and fisheries. This includes coral transplantation and monitoring programs.

Diversification: Coastal communities should explore diversification strategies beyond fisheries and tourism, including aquaculture and alternative livelihoods, to reduce their vulnerability to the impacts of ocean acidification.

Infrastructure Resilience: Governments and communities must invest in resilient infrastructure to withstand the challenges posed by ocean acidification, including sea-level rise and extreme weather events.

Ocean acidification’s far-reaching effects on the economy are undeniable. The decline in fisheries, tourism, and its impact on coastal communities underscore the urgency of addressing this issue.  By reducing carbon emissions and implementing sustainable practices, we can mitigate economic risks, safeguard food security, and protect critical infrastructure, promoting a healthier, more secure global society.

UNESCO Scientists Explain Why the Great Barrier Reef Is in Danger: New Report

great barrier reef in danger
Source: WHC UNESCO/Ko Hon Chiu Vincent

The Great Barrier Reef, located off the Australian coast, is the largest coral reef ecosystem on the planet and one of the most outstanding world heritage sites. It serves as a vast sanctuary for thousands of marine species, protects surrounding islands from storms, provides food, and generates revenue through ecotourism. But the Great Barrier Reef is now in great danger as it experiences its sixth massive coral bleaching event.

A new report from UNESCO scientists explains that the Great Barrier Reef is suffering from accelerating damages from human-caused climate change. They argue that the area must be listed in the record of world heritage sites as “in danger” because the deterioration is accelerating at an alarming phase, pushing the reef’s health beyond its tipping point. 

In this article, we’ll review the main points of the new UNESCO report on the Great Barrier Reef and explore the global response to the report.

Background Information:  What is Ocean Acidification?

Full Report: Report on the Joint World Heritage Centre/IUCN reactive monitoring mission to the Great Barrier Reef (Australia from 21 to 30 March 2022) (UNESCO, Nov 2022)

Why Is the Great Barrier Reef in Danger? 

Since 2015, the Great Barrier Reef has been experiencing massive coral bleaching events due to increasing ocean temperatures and ocean acidification. In fact, in 2021, scientists discovered that the global population of living corals has declined by 50% since the 1950s. This is due in large part to the ongoing usage of fossil fuels such as coal, oil, and gas around the world. 

Recent UNESCO scientists’ assessments of the Great Barrier Reef found that it is experiencing its sixth massive coral bleaching event, pushing the reef’s damage to an irreversible tipping point.

  • During their monitoring, scientists discovered around 750 out of 3,000 reefs within the Great Barrier Reef are suffering from widespread bleaching. That is about 25% of the Great Barrier Reef. 
  • James Cook University marine biology professor Jodie Rummer explains that even the healthiest coral may take a decade to recover from bleaching, and with consecutive mass coral bleaching events, we may not see adaptation and recovery as an option for them. 
  • Scientists predicted that up to 90% of coral reefs around the world may disappear in the next 20 years due to ocean acidification. The Great Barrier Reef is one of the reef areas most affected by acidification.
  • UNESCO scientists’ report argues that the Great Barrier Reef should be added to the list of world heritage sites that are “in danger.” This UN-backed recommendation comes after the World Heritage Committee’s initial recommendation of an “in danger” listing in 2021.
  • The report argues that in order to give the Great Barrier Reef a chance to combat the effects of ocean acidification, we must reduce greenhouse gas emissions, reassess carbon credit schemes and increase financial investment in protecting the reef.

What Was the Response to the UNESCO Report?

UNESCO’s push to list the Great Barrier Reef as “in danger” was received with a mixed response.

  • UNESCO advised the Australian government to boost its carbon-reduction policies and invest more in water-quality improvement programs. However, the Australian government’s policies continue to fall short of UNESCO’s critical recommendations.
  • The Australian government argues that it is unnecessary to list the Great Barrier Reef as “in danger” because they are doing enough to protect the Great Barrier Reef. For example, they cite their recent commitment to invest $1 billion in reef protection programs from 2022 to 2030. 
  • While UNESCO acknowledges that listing the Great Barrier Reef as “in danger” could affect its tourism, it may also establish Australia’s name as a world leader in terms of the conservation and protection of a world heritage site.
  • UNESCO also emphasized that categorizing the Great Barrier Reef as “in danger” on the world heritage list is essential, as it could encourage other countries to join in conservation efforts to protect it. The World Heritage Committee’s decision whether to label the Great Barrier Reef as “in danger” or not will be based on UNESCO’s assessment. UNESCO is still waiting for Australia to ensure compliance with their provided recommendations. However, the Australian government continues to deny that these recommendations are necessary. 
great barrier reef bleaching - great barrier reef in danger
Coral bleaching in the Great Barrier Reef (March 2022)
(Source: WWF Australia/ABC News)

Sources: 

“Great Barrier Reef should be placed on the ‘in danger’ list, UN-backed report shows” CNN, Nov 29, 2022

https://www.sciencedaily.com/releases/2022/05/220525182619.htm

“United Nations recommends Great Barrier Reef be added to World Heritage ‘in danger’ list” ABC News, Nov 29, 2022

https://www.abc.net.au/news/2022-11-29/united-nations-queensland-great-barrier-reef-danger-report/101705908

“Report on the Joint World Heritage Centre/IUCN reactive monitoring mission to the Great Barrier Reef (Australia from 21 to 30 March 2022)” UNESCO, Nov 2022.

https://unesdoc.unesco.org/ark:/48223/pf0000383823

How Does Ocean Acidification Affect the Food Chain? New Research Shows Impacts on Coccolithophores

coccolithophores - how ocean acidification affect food cain
Magnified coccolithophores
Source: UCLA|Photo via hhmi.org

Increases in ocean acidity are damaging the first link in the food chain, a microorganism called coccolithophores. This is causing major impacts to marine species that rely on coccolithophores as their primary source of food. 

Recent research from the Universitat Autonoma de Barcelona’s Institute of Environmental Science and Technology illustrates how ocean acidification is affecting coccolithophores, and thus, how ocean acidification is affecting the food chain as a whole.

Background Information: What is Ocean Acidification?

Full Study: Nutritional response of a coccolithophore to changing pH and temperature (Association for the Sciences of Limnology and Oceanography (ASLO) Aug 2022).

How Ocean Acidification Decreases the Nutritional Content of Coccolithophores

Coccolithophores, part of the phytoplankton family, are single-celled plant-like marine microorganisms that are commonly found close to the surface of the ocean. Despite their microscopic size, coccolithophores play an important role in the marine food chain by serving as its foundation. Many small marine animals rely on coccolithophores as their primary source of food and energy. Even small fish and other organisms that do eat other things, like worms or small crustaceans, feed on coccolithophores when other sources of food are scarce. Marine animals obtain nutrition and energy from coccolithophores’ fat content, known as lipids. 

Coccolithophores build protective scale-like platings around themselves known as coccoliths (the oval platings shown in the image to the right). These coccoliths are made of limestone (calcite). However, ocean acidification makes it much more difficult for organisms to build calcite shells.

A 2022 study conducted by researchers from the Universitat Autonoma de Barcelona’s Institute of Environmental Science and Technology, in collaboration with the Roscoff Marine Station of France, discovered that ocean acidification has significantly reduced coccolithophores’ ability to build shells, and decreased the nutrient content in their bodies. This has massive cascading effects throughout the food chain. Here’s what you need to know about it. 

  • The researchers created a simulation of future climate conditions, causing ocean warming and triggering ocean acidification. 
  • At first, the coccolithophores showed resilience to the increase of ocean temperatures and acidity. The researchers even observed an increase in their population.
  • As the experimental ocean acidity spiked, the researchers found that coccolithophore population growth halted as the organisms began to struggle to build their shells. The acidic conditions caused the coccolithophores’ protective platings (coccoliths) to collapse. While this may seem beneficial to organisms that eat coccolithophores (because this makes them easier to eat and digest), this breakdown of their shells comes with other negative consequences.
  • Researchers also discovered that when coccolithophores were exposed to acidified ocean conditions, the nutritional content in their bodies significantly decreased. As acidification worsens, this reduced nutrient content may have a detrimental impact on the food chain.  Marine species that rely on coccolithophores for food, such as smaller fishes and zooplanktons, would be forced to feed on nutritionally deficient food.
  • Researchers concluded that as ocean acidification affects coccolithophores’ energy and nutrients, coccolithophores may also seek lower-acidity areas to try and slow ocean acidifications’ effects on their survival. This movement will pose an extra threat to marine species that rely on coccolithophores for food, as some may be unable to “follow” coccolithophores to lower-acidity conditions..

The images below show the comparison of healthy coccolithophores (a) and collapsed coccolithophores due to ocean acidification (b).

healthy coccolithophore- how ocean acidification affect food chain
Healthy coccolithophores
(Source: © Phys Org)
collapsed coccolithophore - - how ocean acidification affect food chain
Collapsed coccolithophores
 (Source: © Phys Org)

Read more: Researchers Discover How Ocean Animals Adapt to Ocean Acidification – But Adaptation Comes at a Price

Sources: 

“Ocean warming and acidification impact marine food web” Universitat Autonoma de Barcelona, Nov 2022

https://www.uab.cat/web/newsroom/news-detail/ocean-warming-and-acidification-impact-marine-food-web-1345830290613.html?detid=1345875011926

“Ocean warming and acidification impact the marine food web, study finds” Phys Org, Nov 2022

https://phys.org/news/2022-11-ocean-acidification-impact-marine-food.html

“Nutritional response of a coccolithophore to changing pH and temperature” Association for the Sciences of Limnology and Oceanography (ASLO) Aug 2022

https://aslopubs.onlinelibrary.wiley.com/doi/10.1002/lno.12204

How Ocean Acidification Affects the Development of Several Marine Species

Rising ocean acidity is affecting the development of different types of marine species, such as sea urchins and brightly-colored reef fish.

  1. A recent study shows how sea urchin development is affected by ocean acidification. (more…)
  1. The Great Barrier Reef is experiencing massive coral bleaching events due to ocean acidification, which negatively affects the development of brightly-colored fish in the reef. (more…)

Background Information: What is Ocean Acidification?

Full Research: Direct and latent effects of ocean acidification on the transition of a sea urchin from planktonic larva to benthic juvenile, Are fish communities on coral reefs becoming less colorful? 

Study Shows How Ocean Acidification Affects Sea Urchin Early Stage Development

Ocean acidification has a significant negative impact on marine species and ecosystems. A recent study shows how ocean acidification affects the early development stages of some marine species, such as sea urchins. Here’s what you need to know about it.

The study researched the effects of pH on sea urchin’s development and transition from fertilization to juveniles. The result shows that low pH levels significantly affected the growth and mortality of the urchin’s larval stage. Even small changes in ocean pH (on the scale of .1) can have major impacts.

Larval Stage: Effects of Ocean Acidification

  • Sea urchin larvae were exposed to a 7.2 pH level (compared to the current ocean’s actual pH of 8.1). The sea urchins exposed to this pH exhibited the following characteristics: 
    • Higher mortality rates.
    • Higher abnormality rates. 
    • Lower growth rates.
  • The metabolism of sea urchin larvae exposed to a 7.2 pH level increased as well. The researchers believe that because of this, the urchins may be using additional energy to boost metabolic function, which might limit their growth rates. In other words, the sea urchins adapt to ocean acidification by shifting their energy to boost metabolic function, rather than other important functionalities. Researchers believe that this shift in energy may be what’s causing mortality and abnormalities throughout their development stages.

Settlement Stage

  • Researchers discovered that prolonged exposure to a 7.7 pH level significantly delayed the settlement of sea urchin larvae, an important process during which larvae settle to the ocean floor where they will eventually begin their adult life stages. 
  • However, when the sea urchin larvae were placed under a suitable algal substrate for the settlement stage, the researchers found that the larvae remained unaffected by 7.7 pH levels. This shows that algae may help reduce the effects of ocean acidification on sea urchin larvae.

Metamorphosis Stage

  • The study shows that in the metamorphosis stage, all the sea urchins that were grown at a 7.2 pH level failed to metamorphose. The researchers concluded that sea urchins that are exposed to low pH levels throughout their early development stages may find it hard to impossible to achieve metamorphosis. 
  • However, the study also shows that 30% of the sea urchin larvae that were grown at a 7.6 pH level achieved the metamorphosis stage. This shows the large impact of even a pH change of .4, compared to the 7.2 pH group of urchins.
sea urchin development - ocean acidification sea urchins
The development cycle of a sea urchin.
(Source: © Natural History Museum, London

Read more: How Ocean Acidification Affects Sea Urchins

Ocean Acidification Affects Brightly-Colored Fish Development Through Continuous Coral Bleaching

The Great Barrier Reef is experiencing massive coral bleaching events due to ocean acidification, which negatively affects the development of fish’s color in the reef. Here’s all you need to know about the study.

  • In the span of just three decades, the effects of ocean acidification and global warming have caused the Great Barrier Reef to lose thousands of its coral species. This phenomenon is commonly known as massive coral bleaching events. As a result of this, the number of brightly-colored fish in the Great Barrier Reef is decreasing. 
  • According to the study, the number of different types of brightly-colored fish in the Great Barrier Reef has declined significantly since the massive coral bleaching event of 1998. Scientists believe that the composition of the seafloor (texture, colors, patterns) affects the development of the coloration of fish.
  • Reef fishes developed coloration to protect themselves from predators by adapting to the different coral structures and compositions. Fish would find it useless to produce vibrant colorations in the absence of coral compositions.
  • The study concluded that the loss of vibrant composition and structure of the seafloor due to the massive coral bleaching events has a significant relationship to the inability of many fish to develop their vibrant colors. 
coral bleaching in great barrier reef
6th massive coral bleaching event in the Great Barrier Reef (2022).
(Source: © Earth.org

Sources: 

“Direct and latent effects of ocean acidification on the transition of a sea urchin from planktonic larva to benthic juvenile” Nature, April 01, 2022

https://www.nature.com/articles/s41598-022-09537-7

“Fish on Australia’s Great Barrier Reef are losing their colour as corals die” Independent UK, March 23, 2022

https://www.independent.co.uk/climate-change/news/great-barrier-reef-australia-fish-colour-b2041887.html

Ocean Acidification Laws

Ocean acidification occurs when the pH level of seawater decreases. This is most frequently caused by the ocean absorbing excess CO2 from the atmosphere. Some legislatures have enacted laws that address ocean acidification either directly (as the subject of legislation) or indirectly (through laws that target carbon emissions).

This article will examine laws related to ocean acidification that have been enacted in countries around the world, as well as how they may help address ocean acidification and its consequences.

Background Information: Ocean Acidification Infographic

Table of Contents

ocean acidification laws - globe

Ocean Acidification Laws, Legislations & Bills Around the World

United States

United Kingdom

New Zealand

European Union

Unified International Policy to Address Ocean Acidification

Ocean Acidification Laws Around the World

There are several laws enacted around the world that work to fix the problem of ocean acidification. While not all of these laws were intended to address ocean acidification specifically, many may still work indirectly to reduce acidification.

United States

  • The Clean Air Act  
    • The main goal of this federal law is to regulate sources of air pollution.  It was created by the Environmental Protection Agency (EPA), which sets requirements for all states to provide a strategic plan in order to reduce carbon emissions in order to protect public health and the environment. The law may not be specifically intended to address ocean acidification, but because ocean acidification is caused by an excessive amount of atmospheric carbon, a nationwide reduction in carbon emissions would have a substantial impact on decreasing ocean acidification.
  • The Clean Water Act
    • The Clean Water Act is another U.S. federal law that focuses on the regulation and prevention of water pollution, and the improvement of water quality in the nation. Through this act, the EPA enacted requirements for industries that produce wastewater, created several initiatives to combat water pollution, and implemented standards for surface water contaminants. The Clean Water Act also empowers the EPA to combat ocean acidification since it can be regarded as toxic or chemically imbalanced surface water.
  • Federal Ocean Acidification Research and Monitoring Act
    • This federal law mandated the establishment of the Interagency Working Group on Ocean Acidification (IWG-OA). The interagency group is embodied by multiple government organizations led by National Oceanic and Atmospheric Administration (NOAA). The primary goal of the IWG-OA is to conduct research that will provide more information and discoveries regarding the effects of ocean acidification. It also covers the identification of conservation and adaptation plans for marine resources and areas of the country affected by ocean acidification.

State of California

  • AB 32 and SB 32: Statewide Greenhouse Gas Reduction
    • Assembly Bill No. 32 (signed into law in 2006) required the state to reduce its greenhouse gas (GHG) emissions in order to meet 1990 GHG levels by 2020, while Senate Bill No. 32 (signed into law in 2016) requires the state to cut its GHG emissions to 40% below 1990 levels by 2030. The reduction of emissions will help to lower the amount of atmospheric carbon in the air for the ocean to absorb, thereby reducing ocean acidification. 
  • SB 1363 (2016): Ocean Protection Council: Ocean Acidification and Hypoxia Reduction Program 
    • Senate Bill No. 1363 (signed into law in 2016) developed the California Ocean Protection Trust Fund. This fund is meant to support any research and projects that are initiated to tackle the ocean acidification problem. For example, 2021 research on the restoration of eelgrass in California to mitigate ocean acidification occurred due to the support of this bill. 
  • AB 2139: Ocean Protection Council: Ocean Acidification and Hypoxia Task Force
    • Assembly Bill No. 2139 (signed into law in 2016) developed a task force that focuses on research about the effects of ocean acidification in order to provide policy recommendations to mitigate ocean acidification.

State of Oregon

  • SB 1039 (2017): Ocean Acidification and Hypoxia Action Plan
    • Senate Bill No. 1039 (2017) was created to address the ocean acidification problem in the state. Oregon is impacted by ocean acidification in many ways, including damage to its oyster aquaculture industry. The Oregon Coordinating Council on Ocean Acidification and Hypoxia (OAH Council) was established under this legislation. The main goal of the council is to provide an action plan on how to address ocean acidification and its impact on aquaculture and the environment.  
  • SB 1554 (2020): Funding for ocean acidification emergency in the state

State of Maine

  • LD 1679: An Act to Promote Clean Energy Jobs and to Establish the Maine Climate Council
    • The bill, passed into law in 2019, established the Maine Climate Council, which conducts studies to identify different factors that cause climate change, warming ocean temperature, and ocean acidification. The council is required to develop guidelines for addressing these environmental problems and adapting to their consequences. 

United Kingdom 

  • Climate Change Act of 2008 
    • The Climate Change Act of 2008 was enacted to address climate change. Under this law, the government is required to create a Climate Change Risk Assessment (CCRA) every 5 years. The assessment covers the UK’s risks and opportunities from the effects of climate change.  The government is also required to establish the National Adaptation Programme (NAP), which creates different projects for the country’s adaptation to climate change. One of these projects is the UK Ocean Acidification Research Programme
    • The Climate Change Act of 2008 also requires the reduction of greenhouse gas emissions, with the goal of becoming “Net Zero” by 2050. This large-scale emission-reduction plan would significantly help to decrease ocean acidification.

New Zealand

  • The Climate Change Response (Zero-Carbon) Amendment Act 2019
    • The Climate Change Response (Zero-Carbon) Amendment Act of 2019 mandated the establishment of the Climate Change Commission. The commission’s principal goal is to provide scientifically-grounded recommendations on climate change mitigation and adaptation. This law also aims to achieve “Net Zero” greenhouse gas emissions in the country by 2050. It is the duty of the Climate Change Commission to monitor the country’s progress towards this goal and ensure that the country is on track. The law may not be directly aimed at addressing ocean acidification, but as mentioned above, reducing carbon emissions is the main method to reduce ocean acidification.

European Union 

  • European Climate Law
    • The European Climate Law was enacted to support the objectives of the European Green Deal, which aims to ensure the EU is climate neutral by 2050. It also provides milestones that must be met on the way to achieving climate neutrality in 2050. For example, the European Union is required by this law to reduce 55% of its greenhouse gas emissions by 2030. The European Climate Law will establish methods to monitor progress toward their objective and to guarantee that the target of climate neutrality by 2050 can be met. Although ocean acidification is not the primary focus of the law, it may be addressed by major emission reductions across the European Union.

Unified International Policy to Address Ocean Acidification

There is still no direct united international policy to tackle ocean acidification, despite the fact that many claim that it is as important as the other global problems that need to be addressed. Some argue that the United Nations may use the United Nations Convention on the Law of the Sea (UNCLOS) to design and develop a unified agreement that specifically addresses ocean acidification.

However, the 2015 Paris Agreement may help reduce carbon emissions, and thus reduce ocean acidification.

  • The Paris Agreement is a legally binding international treaty designed to address global climate change issues. The treaty’s principal objective is to lower global temperatures by 1.5 to 2 degrees Celsius. The treaty required all participating countries to provide their climate action plans by 2020. In their submitted climate action plans, all of the countries agreed on one thing: they pledged to cut their greenhouse gas emissions in order to accomplish the agreement’s objective. 
  • Beginning in 2024, progress will be tracked through an enhanced transparency framework (ETF), where each of the participating countries will have to submit its progress report for validation. 
  • While the agreement’s primary goal is to combat climate change in general, ocean acidification may be addressed through the combined greenhouse gas emissions reduction efforts of 192 participating countries and the European Union.

An Ocean Acidification Case Study: How Coral Reefs in the Pacific Basin Are Impacted by Ocean Acidification

Ocean acidification occurs when the pH level of seawater decreases. This is most frequently caused by the ocean absorbing excess CO2 from the atmosphere. By evaluating an ocean acidification case study, we can get a sense of how damaging ocean acidification currently is, and what measures can be implemented to prevent further damage.

This article will outline a case study on how ocean acidification affects coral reefs in the Pacific Basin, as well as proposed solutions to prevent further damage.

Background Information: Ocean Acidification Infographic

About the Case Study

This study, Lebrec et al. 2019, was originally published in the journal “Regional Studies in Marine Science.” It discusses the effects of ocean acidification on coral reefs in the Pacific Basin, where mass coral bleaching has occurred. The case study highlights five coral reef ecosystems in the Pacific basin, which are found in the following locations:

  • Ryukyu Archipelago, Japan
  • Palau
  • Hawaii
  • Marshall Islands
  • American Samoa
coral reef ecosystems map - coral ocean acidification
Locations of coral reef ecosystems highlighted for the case study
Source: Lebrec et al. 2019

The case study evaluates the impact of ocean acidification on the above locations and proposes solutions to prevent ocean acidification and other ocean stressors from causing further damage to coral reefs.

Source: Ocean acidification impacts in select Pacific Basin coral reef ecosystems 

Main Takeaways

Here are the main takeaways from the case study:

  1. Ocean acidification negatively affects the coral reefs in the Pacific Basin by reducing the amount of calcium carbonate that is essential to coral reef skeletal development and coral survival. This causes coral reef death.
  1. The study highlights the importance of unique coral diversity in each of the five geographic locations, as well as the vital role coral reefs play in local communities and economies.
    1. Hawaiian coral reefs are not just important to the tourism industry, but they also provide direct benefits to the community by sustaining fisheries and pharmaceutical production, which generate income through exportations. Hawaiian coral reefs also provide indirect benefits to the community by protecting coastal areas from storms. The economic value of coral reefs in Hawaii is about $455 million USD.
    2. The Marshall Islands is the world’s most coral reef-dependent country. Most of their needs are met by the reef, including employment, nutrition, exportation, tourism, and protection against natural disasters. 
    3. The Ryukyu Archipelago is home to more than 360 species of corals, which makes it the world’s richest endemic coral reef. The archipelago’s coral reef plays an important role in its economy, generating $4.7 billion USD tourism revenue in a single year. 
    4. Palau is home to around 425 species of coral reef, which makes the country the most biodiverse coral reef in all of Micronesia. It provides 40% of the country’s employment, as over 90% of tourists that visit the island come for diving and snorkeling.
    5. American Samoa is home to about 200 coral reef species, which is why the government established 6 major protected areas for coral reefs across the archipelago. 
  1. The locations in the case study are experiencing coral bleaching events due to the combined effects of different disasters, pollution, and ocean acidification. This affects these countries since all of them rely heavily on the services that coral reefs provide. 
    1. Hawaiian coral reefs are bleaching as a result of rising temperatures and ocean acidification, and certain coral reef species are recovering at a slower rate than expected.
    2. Increasing temperatures have bleached over 90% of the coral reefs of Okinawa Island, which is part of the Ryukyu archipelago.
    3. From 1997 to 1998, Palau had a GDP decline of about 3.3% due to intense coral bleaching events. 
coral bleaching - ocean acidification
Coral reef bleaching in Airport reef, Tutuila, American Samoa
Source: Coral Reef Watch/NOAA

Proposed Solutions to Fight Ocean Acidification-Related Bleaching

This case study provides 3 proposed solutions to fight ocean acidification and its damage to the coral reefs in the Pacific basin. 

  1. Adaptation promotes the resilience of coral reefs by initiating conservation regulations and the reforestation of coral reefs, and increasing coral reef protected areas. 
  2. Mitigation covers the reduction of carbon emissions at the global and local scales. This could be in the form of carbon taxation, an emissions trading system, or a cap-and-trade system. 
  3. Capacity Building focuses on promoting local research advancements and spreading education and awareness to the community, generating funds to improve coral reef conservation efforts, and creating local collaborative efforts to promote national policies that push for unified international policies.

Conclusions

This case study highlights the importance of coral reefs in the Pacific Basin and how the countries around it majorly depend on the services that the coral reefs provide. Understanding the impacts of ocean acidification on coral reefs in the Pacific basin can help us promote solutions to ensure their benefits to humans and ecosystems remain intact.

This case study is just a part of a much larger global issue of ocean acidification and its negative effects. There are many other countries around the world that are experiencing not only coral reef bleaching but also damage to marine animals and microorganisms that are essential to maintaining the ecological balance of the world. The case study emphasizes the importance of addressing ocean acidification, as if we fail, people all over the world will lose sources of food, income, and culture.

Is Ocean Acidification Reversible?

Is Ocean Acidification Reversible?

Ocean acidification occurs when the pH level of seawater decreases. This is most frequently caused by the ocean absorbing excess CO2 from the atmosphere, which increases as humans contribute more carbon to the atmosphere.

Ocean acidification has severe impacts on marine ecosystems, marine wildlife, and humans. While some researchers argue that ocean acidification can still be reversed to avoid these negative consequences, others disagree.

This article will examine the varying perspectives of experts and researchers on whether ocean acidification is reversible. We will also discuss proposed methods of reversal and the consequences we might face if we fail to reverse ocean acidification.

Background information: Ocean Acidification Infographic

Table of Contents

Ocean Acidification: Is It Really Reversible?

A Pessimistic Stance

An Optimistic Stance

Different Scientific Methodologies On How to Potentially Reverse Ocean Acidification

Future Impact of Ocean Acidification if Not Reversed

Future Impact on People and the Economy

Future Impact on Marine Life and Ecosystems

Key Takeaways

Is Ocean Acidification Reversible? The Debate

Ocean acidification began in the Industrial Revolution of the 19th century, and has been damaging marine life and ecosystems for centuries now.  Today, ocean acidification continues to worsen. Experts in the field are working to identify whether it’s possible to return the ocean’s pH level, or acidity level, to its former condition in the pre-industrial period. In other words, scientists want to know: is ocean acidification reversible?

A Pessimistic Stance

The Secretariat of Convention of Biological Diversity (CBD) introduced a study in 2009 that focused on the impacts and trajectory of ocean acidification. The study collected 300 scientific reports related to ocean acidification and predicted that ocean acidity may increase by 150% by 2050. This increased acidity will likely cause irreversible damage to marine life and ecosystems. According to a 2009 press release, CBD Executive Secretary Ahmed Djoghlaf stated that “Ocean acidification is irreversible on timescales of at least tens of thousands of years.” This suggests that even with significant interventions, fully reversing ocean acidification will be impossible for our generation and beyond. 

This difficulty in reversing acidification is due to the unprecedented speed with which ocean acidification has occurred; post-Industrial Revolution acidification happened 100 times faster than any previous change in acidity over the past 20 million years. Marine organisms and ecosystems are unable to adapt to increased acidity quickly enough, making it difficult to address or reverse.

Post-Industrial Revolution ocean acidification happened 100 times faster than any previous change in acidity over the past 20 million years.
Source: IUCN

Another study was released in 2015, conducted by Germany’s Potsdam Institute for Climate Impact Research. The research focuses on Carbon Dioxide Removal (CDR) methodologies, which utilize technologies to boost the removal of atmospheric CO2, with the goal of reversing ocean acidification to pre-industrial levels. However, the researchers concluded that even if we achieve a 25 gigatons annual CO2 reduction through CDR, ocean acidification will be impossible to reverse to its pre-industrial condition until the year 2700

Essentially, even after several centuries of carbon removal, oceans will still show the effects of current acidification.

An Optimistic Stance

In 2013, scientists from Lawrence Livermore National Laboratory conducted an experiment where they designed a sequestration method that works to absorb atmospheric CO2, create clean hydrogen fuels and release carbonate and bicarbonate, which improves alkalinity. The goal of this method is to increase alkalinization, or the chemical process of neutralizing acids to stabilize ocean acidity, in order to reverse acidification.

Another similar study released in 2016 focused on how to reduce ocean acidity through the introduction of an alkaline solution. Rebecca Albright of Stanford University and her team conducted an ocean alkalinization experiment in a series of isolated lagoons surrounded by One Tree Reef, a portion of the southern Great Barrier Reef. The team developed a chemical solution made with a mixture of seawater, dye, and sodium hydroxide, which served as the alkaline (acid-neutralizing) solution that was deposited over the reef of the isolated lagoons. The experiment shows that changes in water chemistry through alkalinization successfully lower ocean acidity, and improve coral development. 

However, the study suggests that ocean alkalinization alone is insufficient to reverse ocean acidification, and that in order to reverse ocean acidification fully, it is necessary to address excessive carbon emissions as well. While reversing ocean acidification may be part of a solution, reducing carbon emissions would address the root of the problem. This is why some argue that ocean acidification is reversible only if it is included in political initiatives that promote a wide reduction of carbon emissions.

Another study was released in 2021 that focuses on enhancing ocean alkalization by introducing experiments on a much larger scale: this time, to the whole Great Barrier Reef. In the experiment, 90,000 tons of alkaline solution were deposited into the Great Barrier Reef every three days for one year. The results reveal that the concentration of carbonate ions increased along the reef, a key indicator of ocean acidity levels. In fact, the experiment successfully reversed acidity levels to the conditions that existed four years ago, indicating that ocean acidification can be reversed on small scales or in small amounts, even if conditions cannot be returned to the pre-industrial conditions of 100 or more years ago. This is promising, as even if we cannot return the ocean to its original state, we may be able to stop the worst of ocean acidification’s effects from taking place.

Scientific Strategies to Reverse Ocean Acidification

Scientists and experts around the world have been studying ocean acidification and how to counter it for decades now. Several scientific methodologies that aim to reverse ocean acidification, including those mentioned above, have already been introduced. Here’s an overview of the methodologies and research that are being considered to reverse ocean acidification.

Enhanced Chemical Manipulation 

One of the main methods scientists are researching to reduce ocean acidification is chemical manipulation. This includes ocean alkalization, or introducing a chemical source of alkaline to the seawater in order to stabilize the acidity levels. This method is believed to reduce ocean acidification at the local scale. 

Ocean alkalization process
Source: Ocean Nets

Carbon Emission Reduction

Because the cause of ocean acidification is the ocean’s absorption of excess CO2 from the atmosphere, one of the main strategies to alter increasing ocean acidification is to reduce carbon emissions globally. This could come through different climate-friendly initiatives and government policies, including but not limited to: 

  • Switching to renewable energy sources
  • Implementation of carbon taxes
  • Driving low carbon vehicles, or using electric vehicles
  • Using bicycles and low-carbon forms of transport more often
  • Using energy-efficient appliances
  • Planting more trees

Surface Acidity Pumping

Several recent studies have suggested addressing ocean acidification with surface acidity pumping, the use of electrochemical pumping to relocate surface seawater acidity to the depths of the ocean. This method decreases the acidity level of the surface seawater by bringing up alkaline water from the bottom of the ocean, and then relocating surface acidity to the bottom. This strategy not only controls ocean acidification and benefits coral reefs’ health, but also allows the ocean to capture more atmospheric CO2, which may help to mitigate global warming.

pumping process - is ocean acidification reversible
Electrochemical pumping process
Source: Energy & Environmental Science Tyka et al. 2022

Read more about this strategy: Researchers propose controlling ocean acidity to lower atmospheric carbon dioxide

Future Impacts of Ocean Acidification if Not Reversed

If the current rate of ocean acidification is not reversed, it will have a detrimental effect not just on the environment, but also on the global community. Here are some examples of how ocean acidification will affect humans, the economy, marine species, and ecosystems in the future.

Impact on People and the Economy

Impact on the Aquaculture Industry 

Ocean acidification affects the development and survival of shell-forming marine animals, including oysters, clams, mussels, and many more. This variety of marine animals is widely produced, farmed, and consumed on the global seafood market. With these animals at risk, the shellfish and seafood market might collapse, which may cause job loss and economic fallout, especially in countries and regions that rely on shellfish farming. 

Other fish may also be hard to find on the market as an indirect result of ocean acidification. Salmon and tuna, for example, are two of the most popular seafoods on the market. These fish rely on other smaller fish for food, such as sardines and anchovies. These smaller fish feed mostly on phytoplankton, which is one of the organisms most severely affected by ocean acidification. The imbalances ocean acidification creates in the ocean food chain have an impact on the survival of these popularly-marketed fish. If ocean acidification continues to worsen, much of the seafood that we not only enjoy, but also that generates income and employment and contributes to the economy may not be available decades or centuries from now.

Impact on the Tourism Industry 

The tourism industry is one of the largest contributors to the world economy, but it is also threatened by ocean acidification’s impacts. For example, coral reefs attract tourists, which generates $36 billion for the global economy annually. Many regions rely on coral reefs to generate employment and business. Unfortunately, ocean acidification is already causing massive coral deaths in different parts of the world. If ocean acidification is not reversed, coral population declines will continue, which may create a negative effect on the tourism sector, resulting in job losses and business closures that will negatively impact the people that rely on them.

Impact on Marine Life and Ecosystems

Experts, researchers, and scientists have shown that ocean acidification is already creating detrimental impacts on different marine life and ecosystems. This includes the following discoveries:

  • Ocean acidification is negatively affecting the population and development of phytoplankton and diatoms.
  • Ocean acidification makes it difficult for coral to build their skeletons, which creates an ecological imbalance, and a non-habitable environment for reef fish species. 
  • Ocean acidification negatively affects the capabilities of shell-forming marine species, such as clams, sea urchins, oysters, and mussels, to grow and develop their shells, making them more vulnerable. 
  • Ocean acidification negatively affects salmon’s sense of smell and ability to detect danger. 

All of the scientific discoveries listed above threaten the affected species, and may even lead to an increase in their mortality rate in the long run. Experts are concerned that if we do not stop or reverse ocean acidification, we may witness a repetition of the historical mass extinction that occurred 66 million years ago, when 75% of marine species became extinct due to an overly acidified ocean. If this happens in the future, the damaging impact of this may not only affect the marine life and ecosystem but all life on earth.

Key Takeaways

The possibility of reversing ocean acidification is uncertain. The main arguments can be summarized into three categories:

  • Some argue that ocean acidification is not reversible (especially not to pre-Industrial Revolution levels).
  • Some argue that we can slow ocean acidification down, but not reverse it completely.
  • Some argue that it is scientifically feasible to reduce acidification at least enough to avoid catastrophic consequences. 

While ocean acidity levels likely cannot be returned to pre-Industrial Revolution levels, ocean acidification can be reduced on local scales to the acidity conditions of a few years ago (which is still a much-needed improvement).

Experts are working to find strategies to make this possible, although many of these strategies have not been tested on a larger scale. But one thing is certain about the question, is ocean acidification reversible: Reducing or reversing ocean acidification requires a global unified effort to reduce carbon emissions. If we succeed in achieving this, then the answer might be yes.

How Are Whales Affected by Ocean Acidification?

Ocean acidification occurs when the pH level of seawater decreases, which is most frequently caused by the ocean absorbing excess CO2 from the atmosphere. Ocean acidification has negative effects on a variety of ocean ecosystems and life forms, including whales.

This article will explain how whales are affected by ocean acidification and the importance of whales to ecosystems.

Background information: Ocean Acidification Infographic

Table of Contents

How Are Whales Affected by Ocean Acidification?

The Importance of Whales

Historical Whale Population Decline and Recovery

Whale Conservation Efforts

How Are Whales Affected by Ocean Acidification?

Whales are affected by ocean acidification in numerous ways. 

how are whales affected by ocean acidification

First, whales may suffer from starvation and other diseases due to ocean acidification’s effects on their food supply. The increase of ocean acidity decreases the number of carbonate ions. This ion is essential to most shell-forming organisms including krill, which is the primary source of food for baleen whales, including blue whales and humpback whales. Without enough krill to sustain the whales, they can starve or seek alternate food sources, which may not give the appropriate nutrients the whales need, leading to malnutrition and other diseases.

There are also some studies theorizing that ocean acidification may affect the hearing abilities of whales and dolphins. This is important because hearing is crucial for whale communication.  As the oceans become more acidic, the concentration of borate in the water decreases, which could affect the absorption of sound energy that whales rely on for communication. However, this theory was countered in a 2010 study, in which researchers from the Woods Hole Oceanographic Institution argued that acidification will only have a minimal effect on whales’ ability to communicate.

In summary, ocean acidification may contribute to decline in whale populations. This could become a serious problem for ocean ecosystems and climate change, as whales help to maintain balance in the ocean and atmosphere.

The Importance of Whales

Whales play a crucial role in maintaining balance in the ocean ecosystem, which helps marine life and people alike. Ocean acidification threatens the important services that whales provide. Here are some of the important roles of the world’s largest mammals.

Food Chain Guardians

In their place at the top of the food chain, whales play a very important role in maintaining the balance of the marine ecosystem and the supply of food in the ocean. For example, each day, a blue whale or a humpback whale can eat up to 40 million krill. Due to this massive appetite, overpopulation of krill is prevented, which helps preserve the ecological balance of the marine ecosystem.

Natural Nutrient Suppliers

whale deposits - whales ocean acidification
A blue whale leaving a massive amount of nutrient-rich deposits
Source: Ian Weisse / abc news Australia

Whales also act as fertilizer transporters in the ocean. Whales contribute to ocean fertilization through their deposits and urine. According to research, a sample of whale fecal matter contains 10 million times more iron than the amount of iron present in a sample of ocean water of the same weight. These nutrients are essential to the health and reproduction of different marine organisms, including phytoplankton (which help reduce ocean acidification). Because whales are migratory animals, they supply these nutrients to different ocean locations. 

Climate Change Fighters

Phytoplankton usually thrive where whales are found. This is because whale deposits fertilize phytoplankton, which allows plankton to reproduce and thrive. Each year, phytoplankton absorb around 10-20 billion tons of CO2 from the atmosphere, and are considered the world’s largest producer of oxygen, as they help account for 70% of the world’s oxygen supply. Without the nutrients whales provide, phytoplankton might not flourish, which could greatly affect the ocean’s carbon cycle and increase ocean acidification. 

Historical Whale Population Decline and Recovery

The population of whales started to decline in the 11th century as a result of the growing whaling industry. People hunted whales for oil and other products, including meat, baleen, and ambergris. This activity continued for centuries, causing the populations of different whale species to drop drastically, driving them to extinction.

whaling industry - whales ocean acidification
Soviet whalers during the 20th century.
Source: Hakai Magazine/ Popperfoto/Getty Images

In 1986, the International Whaling Commission (IWC) banned commercial whaling. Because of this, whales are finally able to recover and repopulate. Today, most of the whale species that experienced the decline are now showing some population recoveries. Here is the recent population status of some well-known whale species: 

Humpback Whales 

Today, the humpback whale population reaches about 80,000 as a result of global conservation efforts and policies. 

Fin Whales

Fin whales were one of the most hunted whales during the whaling era of the 20th century, but today, their population is considered healthy, reaching about 75,000.

Blue Whales

Today, blue whale populations are still pushing for recovery. Even though their population is increasing, they are still listed as endangered. The current population of blue whales is between 10,000 – 25,000.

Though ocean acidification is not listed as one of the main sources of whale mortality today, several man-made factors are still causing death to different kinds of whales. This includes: 

  • Ship strikes
  • Plastic pollution
  • Fishing nets entanglement (bycatch)
  • Climate change

Whale Conservation Efforts

Globally, different organizations and government agencies are working to conserve and increase the population of whales. Since ocean ecosystem health is declining due to pollution, ocean acidification, and overfishing, whales and their sources of food are at risk. It is important that we work to conserve them, because they provide us with important services, including (indirectly) the air we breathe.

Here’s an overview of some whale conservation organizations:

World Wildlife Organization

  • For 50 years, the WWF has been running programs to protect whales. The organization participated in the petition banning commercial whaling in 1984.  
  • The organization’s goal is to protect whales and dolphins using three methods: 
    • Improving whale monitoring and mitigating bycatch (accidental entanglement in fishing traps)
  • Preventing ship strikes and reducing underwater noise pollution
  • Protecting whale habitats

Ocean Alliance 

  • Ocean Alliance focuses on increasing public awareness of the importance of whales. 
  • Through the production of 40 documentaries, the organization serves as the bridge between whales and the global community, allowing people to better understand whales and their purpose.

Whale and Dolphin Conservation

  • Whale and Dolphin Conservation has been working on whale conservation efforts for 30 years. The organization has been successful in its mission in various ways: 
    • Stopping commercial whaling
    • Preventing and fighting against whale captivity
    • Preventing and reducing entanglements (bycatch)
    • Promoting sanctuaries and protected areas for whales and dolphins 

How Are Sea Urchins Affected by Ocean Acidification?

Ocean acidification occurs when the pH level of seawater decreases, which is most frequently caused by the ocean absorbing excess CO2 from the atmosphere. Ocean acidification has negative effects on a variety of ocean ecosystems and life forms, including sea urchins.

This article will explore how sea urchins are affected by ocean acidification, as well as the importance of sea urchins to ecosystems, global cultures, and the economy.

Background information: Ocean Acidification Infographic

Table of Contents

How Are Sea Urchins Affected by Ocean Acidification?

The Importance of Sea Urchins

The Importance of Sea Urchins to the Ecosystem

The Importance of Sea Urchins to People and the Economy

How Are Sea Urchins Affected by Ocean Acidification?

Sea urchins are vulnerable to ocean acidification because rising acidity in seawater reduces the number of available carbonate ions, which are essential for building sea urchins’ shells, spines, and teeth. Here are some of the negative effects of ocean acidification on sea urchins. 

Lowered Growth Rate of Sea Urchin Larvae

Because larval sea urchins are quite sensitive, ocean acidification affects the development of sea urchins at very early stages. According to a 2022 study, sea urchin larvae’s growth rate is lowered when they’re exposed to acidified water. Sea urchins, when exposed to lower pH seawater, need to use extra energy for other survival functions, including temperature self-regulation, leaving insufficient energy for them to use for their growth.

Increased Metabolism

Sea urchins feed on various types of marine organisms, including algae, planktons, and even kelp. Feeding is crucial to the growth, development, and survival of sea urchins. However, 2013 research discovered that increasing ocean acidity affects the metabolism of sea urchin larvae, forcing them to eat more than normal. A lower pH level reduces the capability of sea urchin larvae’s digestive enzymes, known as “gastric juice.” In order to attempt to make up for less effective digestion, sea urchin larvae exposed to acidification increased their feeding by as much as 33%. If this increased eating was not possible due to a lack of food, the sea urchin would suffer. Additionally, this increased energy devoted to eating reduces energy reserves for other vital functions such as growth and temperature self-regulation.

Increased Developmental Abnormalities and Mortality Rates

Ocean acidification forces sea urchins to reallocate their energy sources in order to adapt. This might sound positive, but experts have found that it is one of the causes of mortalities and abnormalities in sea urchins. In a 2022 experiment, sea urchin larvae were exposed to acidified water with a 7.2 pH level (much lower than the ocean’s current pH of 8.1). This showed a significant effect, causing abnormalities to the sea urchin’s structural development. 

In the same experiment, when larval sea urchins were exposed to acidified water with a pH of 7.2, they were unable to grow into juvenile sea urchins. These abnormalities may threaten their survival rate.

sea urchin study - sea urchin ocean acidification
Comparison of two sea urchins, where the sea urchin on the right is exposed to ocean current conditions, and the sea urchin on the left is exposed to ocean acidification.
Source: Phys.org

The Importance of Sea Urchins

Sea urchins contribute to the ecological balance in the ocean ecosystem and provide products that are used in traditional cuisines. However, ocean acidification threatens sea urchin populations, and thus, the benefits they offer to ecosystems and people. Here are some of the ways sea urchins are important to ecosystems and people.

The Importance of Sea Urchins to the Ecosystem

Reef Gardeners 

Sea urchins are herbivores and they feed on algae and other marine plants in the reef. Their feeding activities are essential to the balance of the reef because as they remove overgrown weeds and algae, they create room for corals to flourish. This provides more habitat for fish while also preventing the negative effects of overgrowing algae on the reef.

This service that sea urchins provide plays an essential role in maintaining a healthy and habitable marine ecosystem. They are great alternatives to the decreasing population of other algae controllers that are commonly overexploited by people, such as parrotfish and rabbitfish. If ocean acidification continues, the service of sea urchins to reef maintenance could be affected. Without sea urchins and other algae controllers, the reefs as we know them might become uninhabitable for many organisms in the future. 

Source of Food for Other Species

sea otter eating urchins - sea urchin ocean acidification
Sea otter eating sea urchins
Source: Katherine johns / listal

Sea urchins are a food source for several other species. Sea urchins’ high protein provides essential nutrients to animals that rely on this diet. Animal species that feed on sea urchins include:

  • Other shellfish, such as crabs and lobsters 
  • Multiple fish species, such as sheephead wrasse and wolf eel
  • Sea otters
  • Seagulls

Some of these animals use sea urchins as their primary source of food, which is why the negative impact of ocean acidification doesn’t only affect sea urchins directly; it can also cause an indirect effect on species that rely on their services. 

The Importance of Sea Urchins to People and the Economy

How Sea Urchins Benefit the Cultural Food Industry and Economy

Like any other commercialized shellfish on the market, sea urchins are also in demand in some countries’ food industry. Here is an overview of some of the countries that use sea urchins as part of their food industry. 

Chile

Chile has a long tradition of eating sea urchins, as sea urchins have been part of Chilean food since the 1500s. Today, sea urchin is still a part of the Chilean diet. In 2002, Chile consumed around 3,000 tons of sea urchins, and in 2013, Chile ranked as the world’s largest supplier of fresh and frozen sea urchins and urchin roe. Sea urchins are not only a part of Chilean tradition and culture, but they also make a significant contribution to Chile’s economy today.

Japan

sea urchin sushi - sea urchin ocean acidification
Sea urchin sushi
Source: Sushi Making Kit

Eating sea urchins in Japan is traditional, with consumption accounting for around 90% of the global supply. Japan is the largest consumer of sea urchins in the world, where it is commonly eaten as sushi and sashimi, two of Japan’s most iconic dishes. The sea urchin also contributes significantly to Japan’s economy since the country is considered a major exporter of sea urchins globally.

The population of sea urchins may decline as a result of the effects of ocean acidification. This could have a damaging effect not only on the economic contribution of sea urchins, but also on culinary cultures that have been passed down for centuries. 

Health Benefits from Sea Urchin in the Diet

Despite their threatening appearance, sea urchins can provide various health benefits and nutrients to people. Here are some examples: 

  • Sea urchins are high in protein, which can help maintain and grow our muscles.
  • Sea urchins are also rich in dietary fibers that are good for digestion.
  • Sea urchins contain vitamin C and Zinc, which are great for the immune system.
  • They also contain vitamin A, which is good for our organs, such as the heart, kidneys, and lungs.
  • Just like other fish, sea urchins are rich in omega 3 fatty acids, which are useful for maintaining a healthy heart.

Sea urchins provide a variety of valuable benefits to the environment, wildlife, and humans. Several studies have already proven how the acidifying ocean affects their development, preventing them from thriving. This could alter the important services they provide that help in maintaining ecological balance. This is why it is essential to assure that sea urchins, like all other species, are protected from the damaging consequences of ocean acidification.

How Are Salmon Affected by Ocean Acidification?

Ocean acidification occurs when the pH level of seawater decreases, which is most frequently caused by the ocean absorbing excess CO2 from the atmosphere. Ocean acidification has negative effects on a variety of ocean ecosystems and life forms, including salmon.

This article will explain how salmon are affected by ocean acidification, as well as the importance of salmon to ecosystems, people, and the economy

Background information: Ocean Acidification Infographic

Table of Contents

How Are Salmon Affected by Ocean Acidification?

The Importance of Salmon

Ecosystems and Wildlife

People and the Economy

How Are Salmon Affected by Ocean Acidification?

salmon ocean acidification
Source: Timothy Knepp

Salmon and other fish species feel the impact of ocean acidification. As acidity levels rise in the ocean, chemical imbalances are created within their bodies, which are normally balanced with the pH of the surrounding water. This can affect salmon’s behavior and abilities. Here are some of the ways ocean acidification negatively affects salmon.

Ocean Acidification Affects Salmon’s Ability to Sense Danger

Salmon are known for their extreme sense of smell, which is essential for them to search for food and avoid predators. However, when ocean acidification rises, salmon’s ability to smell is altered. According to a 2018 study, salmon that have been exposed to acidified seawater stop showing a response to the scent that tells them there’s danger nearby.

In the study, researchers created three separate salmon tanks, each with a different level of seawater acidity. After two weeks of exposure to the water, salmon in the tank with the lowest acidity levels exhibited normal reactions when the “danger scent” was put into the water. In fact, most of the time, the low-acidity salmon entirely avoided the section of the tank where the scent was coming from. On the other hand, salmon in the tank with the highest acidity levels did not respond to the “danger scent” at all, and made no attempts to avoid it.

The study reveals that ocean acidification can negatively affect salmon’s ability to sense danger. This may result in an increased mortality rate and population decrease in salmon exposed to ocean acidification.

Watch how acidic water affects salmon’s sense of smell in this demonstration from the University of Washington:

Ocean Acidification Affects Salmon’s Ability to Navigate Home

Salmon are anadromous, which means that as they mature, they migrate from the ocean to their natural spawning grounds in rivers to lay eggs. They use their extreme sense of smell to navigate the seas and rivers. This phenomenon is essential for salmon to reproduce and thrive. Unfortunately, the effects of ocean acidification on their sense of smell alter their ability to navigate home. This could prevent them from reproducing and spawning, which could also contribute to declines in their population. 

Ocean Acidification Reduces Salmon’s Food Sources

In the wild, salmon mainly feed on crabs, krill, and shrimps. the negative effects of ocean acidification may impact the populations of shell-forming organisms, including many species that salmon commonly rely on for food. This could lessen the availability of salmon’s food sources, which could lead to starvation, or changing their diet. This might result in a decline in the essential nutrients salmon get from their original diet to sustain their characteristic pink features and health. In the long run, this may raise their mortality rate, reducing their population.

The Importance of Salmon

Salmon play an important role in maintaining healthy ocean and river ecosystems. They also provide benefits for marine wildlife, terrestrial wildlife, and people. However, the increasing threat of ocean acidification puts the important services that salmon provide at risk. Here are some of the ways salmon are important to ecosystems, wildlife, and people.

The Importance of Salmon to Ecosystems and Wildlife

Natural Nutrient Transporter

Since salmon are anadromous, they contribute to the transportation of nutrients from the ocean to rivers and streams. For example, in Alaska, approximately 170 tons of phosphorus are transported from the oceans to Lake Illiamna annually due to the migration of sockeye salmon. Aside from phosphorus, salmon also provide nitrogen to rivers, streams, and lakes. After they lay eggs, salmon die and release nitrogen into the waters. Phosphorus and nitrogen are essential to the growth of microorganisms and vegetation, and provide necessary nutrients to wildlife that inhabit the lake.

Food Source for Wildlife

Salmon serves as food for various types of marine and terrestrial animals. Here are some of the species that rely on salmon as their source of food:

  • Brown bears rely on a salmon diet for the rich calories it provides. Salmon are essential for bears, as bears need to consume around 5,000 to 20,000 calories per day, depending on the season.
  • Sharks, seals, and orcas consume salmon in the ocean. Salmon provides nutrients that are essential for their growth.
  • Bald eagles and other predatory birds that live on riversides feed on salmon when the fish return to their spawning grounds in shallow rivers and streams.
Alaskan brown bear catching salmon in Brooks Falls
Source: Gary Lackie/Flickr

The consequences of ocean acidification may have an impact on the availability of salmon in areas where animals and plants rely on them for nutrients and food. If the ocean continues to acidify, it will not only harm salmon, but will also have a detrimental domino effect on the ecosystem and other species that rely on the fish.

The Importance of Salmon to People and the Economy

How Salmon Benefit the Aquaculture Industry 

Industrialized salmon farming started in the 1980s in Norway and quickly grew into a global industry. Today, salmon aquaculture is one of the fastest growing methods of food production today, and makes up about 70% of the global market. Salmon have a huge impact on the global economy, so the effects of ocean acidification on salmon could be quite disruptive. 

How Salmon Benefit People’s Livelihoods 

In 2018, almost 60 million people relied on the aquaculture industry for their source of income. Because salmon is the most-produced fish in the global aquaculture industry, it provides millions of people with employment and income. 

Health Benefits of Eating Salmon

salmon on plate - salmon ocean acidification

In the 1980s, salmon was considered a fancy dish in some countries, but as the industry grew salmon became more widely available, and the health benefits and nutrients it provides to humans spread to practically every corner of the globe. Here are some examples of the health benefits of salmon:

  • Salmon is a good source of protein, which is essential to building muscle mass and growth. 
  • Salmon is rich in vitamin b12 and iron, which are essential to the formation of red blood cells. This can prevent blood-related conditions like anemia. 
  • Salmon contains potassium, which is essential in maintaining healthy muscle condition and nerve function.
  • Salmon also contains vitamin D, which boosts immune systems. 
  • Salmon contains high omega 3 fatty acids. This is great for maintaining a healthy heart and reducing the chance of getting several diseases such as heart attacks, cancer, dementia, and Alzheimer’s. 

The issues salmon face from ocean acidification are exacerbated by the negative pressures humans have placed on salmon populations. This includes urbanization, pollution, and dam constructions. If worsening ocean acidification is added to these pressures, salmon may not be able to continue to adapt to declining environmental conditions, and their populations will suffer.

Salmon provide a variety of services and health benefits to people, the economy, wildlife, and ecosystems, but they are threatened by ocean acidification. Ocean acidification jeopardizes the benefits we get from salmon and it may also create an ecological imbalance that could lead to other species’ extinction.