13 going on 195: The Race to Stop Ocean Acidification

Professor Steve Widdicombe  I  Director of Science at Plymouth Marine Laboratory

As governments and scientists gather in Cali to assess global biodiversity targets, one issue is particularly neglected – ocean acidification. Despite its critical threat to marine ecosystems, only 13 nations out of 195 (just 7% of the world) have developed national ocean acidification action plans. With 182 more countries yet to take similar steps, the clock is ticking to curb a phenomenon that is already unravelling marine life, food chains, and entire economies.

Ocean acidification occurs when excess carbon dioxide dissolves into seawater, lowering its pH. This subtle yet destructive shift in ocean chemistry disrupts the delicate balance that marine species depend on. With rising acidity, these vibrant ecosystems are slowly disintegrating. The effects don’t stop there—species of shellfish, coral and plankton are struggling to survive in these altered conditions, threatening the base of marine food chains and harming coastal communities that rely on fishing.

Yet, governments are slow to act.

Target 8 of the Global Biodiversity Framework calls for minimising ocean acidification’s impact on marine biodiversity. Despite this, very little is being done to tackle this overlooked ocean threat.

This lack of action stems mostly from a gap in research and funding for adequate monitoring.

Without sufficient data linking ocean acidification directly to biodiversity loss, policymakers feel less urgency to address it. The causality, though acknowledged by scientists, needs clearer, irrefutable documentation to generate the global urgency needed for more policy action.

Contrast this with the rapid progress of the UN Global Plastics Treaty, which is nearing completion and promises transformative changes for both ocean and human health. Ocean acidification, however, is still at the starting line. Why the disparity? Plastic pollution is a visible, tangible problem. Its impacts—choked marine life, plastic-strewn beaches—are clear. Ocean acidification, on the other hand, is an invisible threat, harder to detect but no less devastating in the long term.

As our oceans acidify, fisheries are projected to see declines in key species, threatening food security for millions of people globally. Coastal economies that depend on marine biodiversity will suffer significant losses. These aren’t hypothetical scenarios—they are looming realities that require immediate action. Governments in Cali must commit to advancing research that will substantiate the link between ocean acidification and biodiversity decline, accelerating the process of creating actionable plans.

Research isn’t just about gathering data – it’s about creating a sense of urgency. Clear evidence of the damage ocean acidification is causing will force governments to make it an integral part of national biodiversity legislation.

There’s no more time to waste. Our oceans are in crisis, and without intervention, we may soon pass the point of no return. It’s time to take ocean acidification seriously, and to match the urgency seen in the plastics treaty.

To policymakers in Cali – by the time we get to the next global biodiversity summit, please don’t let us still be stuck at the starting line.

Read more about this issue: Ocean acidification and biodiversity loss: Connecting the dots with data, a report written by Economist Impact for Back to Blue, an initiative of Economist Impact and The Nippon Foundation, featuring interviews with PML’s Professor Steve Widdicombe.