Oceans and the triple planetary crisis

The world’s oceans are endangered by the triple planetary crisis, but they also offer significant opportunities for action

- By Dennis Mombauer

OCEANS cover the vast majority of Earth’s surface area and absorb nearly a quarter of global carbon dioxide emissions.

They are a major reservoir of biodiversity and home to a variety of highly biodiverse marine and coastal habitats, including mangrove forests, coral reefs, and seagrass meadows. Furthermore, they provide food and livelihoods for billions of people across the globe, with the so-called “blue economy” being estimated at $3-6 trillion per year and accounting for more than three quarters of the world’s trade.

However, their unique importance for climate change mitigation, adaptation, biodiversity, and human livelihoods simultaneously puts oceans at the centre of the triple planetary crisis: both as a system at risk and as a possible provider of solutions. Especially for island countries such as Sri Lanka, oceans can play an integral part for sustainable economic growth, environmental conservation efforts, and climate action, but only if they are themselves protected from the threats of climate change, biodiversity loss, and pollution.

Currently, the vital services provided by oceans are collapsing under the pressure of climate change and human activities. Over the last 50-100 years, 90% of large predatory fish have vanished. Even with just 1.5°C of global warming, coral reefs could decline by 70-90%. Acidification, algal blooms, and bacterial outbreaks proliferate. For Sri Lanka and many other vulnerable developing countries, these impacts are not abstract science but could unfold into an ecological and livelihood catastrophe.

State of the oceans in 2025