Turning the Tide on Ocean Health at COP30
Photo by Ishan @seefromthesky on Unsplash
Covering over 70% of the planet, oceans regulate global climatic conditions, support marine biodiversity, and provide income and nutrition for billions of people. However, the planet’s oceans are under severe threat. In its latest annual health assessment – carried out by the Potsdam Institute for Climate Impact Research – researchers found that ocean acidity levels had crossed a critical threshold for marine life. Ocean health is declining due to multiple pressures, including climate change, overfishing, pollution, and habitat destruction. Urgent global action is needed to halt marine health decline.
Two consequences of these pressures are warming waters and acidification, which disrupt species distribution, destroy fragile marine habitats like coral reefs, and reduce oceanic oxygen levels. Simultaneously, destructive fishing practices deplete fish populations and damage habitats, while land-based pollution, such as plastics, agricultural runoff, and waste, suffocates ecosystems. Together, these drivers accelerate biodiversity loss, undermining the resilience of marine ecosystems and the services they provide.
The loss of biodiversity is striking: coral reefs, which occupy less than 1% of the ocean floor but support more than 25% of marine life, are bleaching at unprecedented rates. Meanwhile, mangroves and seagrass meadows, which are vital carbon sinks that sequester three times the volume of carbon stored by tropical forests of the same size, are being cleared for coastal development or degraded by marine pollution. These ecosystems are not only critical carbon stores but also protect coastlines, support fisheries, and safeguard the livelihoods of billions of people. When they decline, so does our capacity to mitigate and adapt to climate change.
As COP30 - which will be held in Brazil from 10-21 November - approaches, ocean health must be central to climate negotiations. The COP presidency’s vision for “A global mutirão” (a community effort for a shared task) highlights that ocean conservation requires collective action across governments, scientists, Indigenous peoples, and local communities. This means scaling up financing for marine conservation initiatives, embedding ocean-based solutions into national climate strategies, and restoring degraded ecosystems. Given that Belem - a city known as the “gateway to the Amazon” – is the host of COP30, it’s hoped that governments will also adopt Indigenous-led initiatives and integrate Traditional Ecological Knowledge into future marine regulation and conservation plans.
The global challenge now lies in turning ambition into action. Analysis released during New York Climate Week in September revealed that fully implementing existing ocean-based climate solutions could close the gap to Paris Agreement emissions reduction pathways by as much as 35%. Yet, realising this potential requires substantial investment. At COP29, nations committed to mobilising $1.3 trillion in annual climate finance by 2035. With available ocean-based solutions already proven to reduce emissions and keep the Paris Agreement’s 1.5°C target within reach, funding for these initiatives must be integrated into final climate finance commitments that will once again be discussed at COP30.
Protecting the ocean is essential for stabilising global climate conditions, preserving biodiversity, and ensuring a sustainable future for all.