Ocean Acidifications

Published on 05 Apr 2025

Ocean Acidification refers to a reduction in the pH of the ocean over an extended period of time, caused primarily by uptake of carbon dioxide from the atmosphere.

Causes of Ocean Acidification

The main cause of ocean acidification includes human activities which release excess amounts of carbon dioxide. These activities are as follows: 

• Burning of fossil fuels: Combustion of fossil fuels such as coal and natural gas release large amounts of carbon dioxide.

• Example: According to World Nuclear Association, Worldwide emissions of carbon dioxide (CO2) from burning fossil fuels total about 34 billion tonnes (Gt) per year.

• Deforestation: Elevated atmospheric CO2 levels are a result of deforestation, which decreases the amount of plants that can absorb CO2.

• Example: EOS Data Analytics shows that Every year, approximately 4.8 billion tons of carbon dioxide are released into the Earth’s atmosphere because of deforestation, particularly in tropical areas.

• Industrial Emissions: Certain industrial processes emit carbon dioxide into the atmosphere.

• Example: In 2022, figures reached a high of 164 million metric tons of carbon dioxide (MtCO₂) from cement industries.

• Waste Incineration: Accumulation of municipal wastes and other industrial waste are a source of carbon dioxide in the atmosphere.

• Example: According to US EPA report, U.S. food loss and waste embodies 170 million metric tons of carbon dioxide equivalent

• Burning of agricultural residue: Agricultural residue burning produces large amounts of carbon dioxide.

• Example: A study by IISER Bhopal with international collaborators revealed that Greenhouse gas emissions went up 75 per cent in 10 years due to farm waste burning.

Impacts of Ocean Acidification

• Degradation of coral reef: Reduced pH interferes with corals' capacity to form skeletons, resulting in weakened and more fragile coral structures.

• Example: The Great Barrier Reef is facing the challenges of ocean acidification, primarily driven by the absorption of carbon dioxide (CO2) by seawater.

• Food Web Disruption: Disruptions in the growth and survival of essential species, particularly those at the base of the marine food web, can have a domino impact on the entire ecosystem.

• Example: According to ICTA-UAB in collaboration with Roscoff Marine station identified that coccolithophores showed reduced nutritional content due to ocean acidification.

•  Impact on cloud formation: Ocean acidification results in the reduced production of dimethyl sulphide (DMS) by phytoplankton which results in less cloud formation, raising global temperature.

• Ecosystem Services: The services that marine ecosystems offer to humans, such as protecting coastlines, recycling nutrients, etc. may be impacted by their declining health.

• Example: Pacific salmon and clownfish were found to lose their abilities to differentiate between prey and predator or locate suitable habitats respectively.

• Impact on Fishing industry: Declines in fish supplies could have an economic impact on the aquaculture and fishing businesses, which depend on healthy marine ecosystems.

• Example: Study in the US has projected that acidification could result in the loss of oysters and scallops by 50 and 55 per cent respectively by 2100

International initiatives

• IAEA Ocean Acidification International Coordination Centre (OA-ICC): It organizes training courses in Member States and provides access to data and resources to advance ocean acidification research.

• Global Ocean Acidification Observing Network (GOA-ON): It is a collaborative international network to detect and understand the drivers of ocean acidification in estuarine-coastal-open ocean environments.

• OA Alliance: It brings together governments and organizations from across the globe dedicated to taking urgent action to protect coastal communities and livelihoods from the threat of ocean acidification.

Way Forward

• Mitigation of CO2 Emissions: Reducing atmospheric CO2 levels can be achieved through switching to renewable energy sources, increasing energy efficiency, and putting sustainable land-use policies. 

• Ocean Conservation and Restoration: Put conservation measures in place to safeguard marine ecosystems, such as creating marine protected areas and restoring harmed habitats.

• Adaptation strategies: Develop and implement adaptation methods at the local and regional levels to address specific issues provided by ocean acidification.

• Policy and Regulation: Adopt and implement laws and rules that support sustainable practices and lower carbon emissions.

Tags:
Environment

Keywords:
Marine ecosystem Acidification Acid rain Water pollution Pollution

Syllabus:
General Studies Paper 3

Topics:
Environment and Climate Change