Ocean acidification is one of the less visible but most serious consequences of climate change. It occurs when the oceans absorb excess carbon dioxide (CO₂) from the atmosphere—a process that has accelerated rapidly due to human activities like burning fossil fuels and deforestation. When CO₂ dissolves in seawater, it forms carbonic acid, which lowers the ocean's pH. Since the start of the industrial era, the ocean has become approximately 30% more acidic, marking a significant shift in its chemistry over a relatively short period. This acidification disrupts marine ecosystems, particularly affecting organisms that rely on calcium carbonate to build their shells and skeletons—such as corals, oysters, clams, and some plankton. As the pH drops, it becomes harder for these organisms to form and maintain their structures, leading to weaker shells and slower growth. Coral reefs, often referred to as the 'rainforests of the sea,' are especially vulnerable. Weakened coral skeletons make reef systems more prone to collapse, which threatens the biodiversity they support and the millions of people who depend on them for food, tourism, and coastal protection. The effects ripple through the entire food chain. When small shell-forming organisms struggle to survive, larger animals that feed on them—like fish and whales—also face risks. This destabilization can lead to a decline in fish populations, which directly impacts global food security. Moreover, many communities, especially in island and coastal regions, rely heavily on healthy marine ecosystems for their livelihoods. Thus, ocean acidification is not just an environmental issue—it’s an economic and humanitarian one as well.