ABSTRACT
Oceans, often described as the “blue lungs” of the planet, are essential for regulating Earth’s climate by absorbing a major portion of human-induced carbon dioxide. While this function mitigates global warming, it also triggers the lesser-known crisis of ocean acidification. The excessive absorption of CO₂ forms carbonic acid, reducing seawater pH and altering marine chemistry. These changes severely impact calcium carbonate–dependent species such as corals, shellfish, and plankton, leading to coral reef degradation, biodiversity loss, and disruption of food webs. Consequently, fisheries, coastal tourism, and ocean-based livelihoods—especially in countries like India—face serious economic risks.
This paper offers an interdisciplinary analysis of ocean acidification through scientific, ecological, and legal perspectives. It explains the causes and ecological impacts of declining pH and evaluates major global frameworks, including the United Nations Convention on the Law of the Sea (UNCLOS), United Nations Framework Convention on Climate Change (UNFCCC), Paris Agreement (2015), Convention on Biological Diversity (CBD), and Sustainable Development Goal (SDG) 14.3. India’s domestic efforts under the Environment (Protection) Act, 1986, Coastal Regulation Zone (CRZ) Notification, and National Action Plan on Climate Change (NAPCC) are also examined.
The study highlights major legal and governance gaps, such as the absence of binding pH standards and weak enforcement mechanisms. It advocates for a unified legal regime to regulate seawater quality, strengthen regional cooperation, and apply the public trust doctrine to marine governance, ensuring the resilience of life below water.
Keywords: Ocean acidification, marine biodiversity, environmental governance, UNCLOS, climate law, public trust doctrine, SDG 14.
- Introduction
Oceans cover more than 70% of the Earth’s surface and function as the planet’s “blue lungs,” playing a critical role in regulating the global climate.[1] They act as a natural carbon sink, absorbing nearly one-third of anthropogenic carbon dioxide (CO₂) emissions, which mitigates the greenhouse effect and slows global warming.[2] However, this beneficial function has an unintended and often underappreciated consequence: ocean acidification.[3] Ocean acidification refers to the process by which seawater absorbs excessive CO₂, forming carbonic acid (H₂CO₃), which dissociates into bicarbonate (HCO₃⁻) and hydrogen ions (H⁺), lowering the ocean’s pH.[4]
This chemical transformation has profound ecological implications. Species reliant on calcium carbonate (CaCO₃) for their shells and skeletons, such as corals, shellfish, and certain plankton species, experience shell dissolution and structural weakening.[5] The resulting degradation of coral reefs disrupts marine food webs, reduces biodiversity, and threatens ecosystem services on which millions of coastal communities depend.[6] In India, where fisheries, tourism, and coastal livelihoods are economically significant, these impacts are particularly concerning.[7]
The purpose of this paper is to analyze ocean acidification from a multidisciplinary perspective, integrating insights from marine science, ecology, and environmental law. It examines both international and domestic legal responses, highlights gaps in governance, and proposes pathways for comprehensive regulation of ocean health to safeguard marine biodiversity.
[1] G. Kleypas et al., Coral Reefs and Ocean Acidification: Science, Impacts, and Policy, 2019.
[2] IPCC, Climate Change 2022: Mitigation of Climate Change, 2022, p. 147.
[3] R. Feely et al., “The Impact of Anthropogenic CO₂ on Ocean Chemistry,” Science, 2004, 305: 362–366.
[4]Ibid.
[5] D. Hoegh-Guldberg et al., The Ocean and Climate Change, 2017, p. 88.
[6] J. Brander et al., Ecosystem Services and Fisheries, 2015, p. 54.
[7] Ministry of Environment, Forest and Climate Change, State of India’s Oceans, 2021, p. 23.