Humanity’s Future Depends on a Healthy Ocean

A coral reef grows off the coast of an island in French Polynesia.

The ocean covers more than 70 percent of the planet and regulates climate, sustains biodiversity, and supports economies and cultures worldwide. It is the foundation of life on Earth.

However, it has been under increasing pressure for some time and now faces multiple threats that not only endanger its ecological health but also the future of humanity itself.

Around 550 experts from 86 countries spent nearly five years compiling a 1,600-page assessment detailing the challenges facing the ocean. This scientific work provides essential knowledge needed to protect and sustain the planet.

It is called the World Ocean Assessment, and here is what those 1,600 pages reveal.

The Ocean Matters to Everyone, Everywhere
The ocean shapes daily life even for those who do not live in coastal areas.
It stabilizes the climate by absorbing most of the planet’s excess heat and harmful greenhouse gases. Without this cooling effect, more extreme weather would threaten food systems, supply chains, and insurance markets.
It provides a critical food source. When fish stocks collapse or supply chains are disrupted due to climate change or illegal fishing, prices rise—not only for seafood but also for other foods linked to global trade and coastal economies.
It supports mental and physical health, provides medicines, and produces a significant share of the planet’s oxygen.
It underpins trillions of dollars in global trade, tourism, and employment.
The Ocean Is Under Intensifying Stress

Humans are reshaping marine ecosystems. The global population reached 8.2 billion in 2024, with 37 percent living within 100 km of coastlines.

This has concentrated economic activity in vulnerable coastal zones, increasing resource extraction, infrastructure expansion, waste discharge, and habitat degradation.

At the same time, offshore development is accelerating, with wind farms, deepwater oil infrastructure, and expanding seabed cables and pipelines altering ecosystems farther from shore.

Climate Change Is Transforming Ocean Conditions

Recent data on ocean warming and sea level rise is alarming:

Sea level rise, driven by melting ice sheets and thermal expansion, has accelerated from 1.9 mm per year before 2015 to 4.3 mm per year in 2023.
Arctic temperatures are rising four times faster than the global average.
Hypoxic “dead zones,” where oxygen levels are too low for most marine life, now cover 4.5 million km².
About 16 percent of total ocean warming since 1955 has occurred since 2018.
Biodiversity Is Declining Across Marine Habitats

Marine life is under severe stress. Caribbean coral reefs have declined by approximately 80 percent since the 1970s. If global warming exceeds 1.5°C above pre-industrial levels, up to 90 percent of coral reefs could disappear.

Coastal ecosystems such as mangroves and seagrass beds continue to shrink. Species from plankton to marine mammals are shifting toward the poles as oceans warm, while invasive species spread more easily in altered environments.

Pollution Is Widespread and Increasing

Marine pollution is worsening:

Around 52 million tonnes of plastic enter the ocean each year, contributing to an estimated 24 trillion microplastic particles affecting over 4,000 marine species.
More than 4,000 pharmaceutical and personal care chemicals have been detected in marine environments.

Some progress has been made, however. Legacy pollutants such as mercury have declined in certain regions.

Ocean Food Systems Are Under Threat

Marine ecosystems provide about 20 percent of the animal protein consumed globally.

Yet stability is declining:

37 percent of fish stocks were overfished in 2021.
Illegal, unreported, and unregulated fishing removes an estimated 8–14 million tonnes annually.
Pollution, disease, and climate stress are undermining aquaculture and fisheries.
The Ocean Economy Is Large but Unsustainable

The ocean economy is valued at around $1.5 trillion annually and is projected to exceed $3 trillion by 2030. Coastal and marine tourism supports approximately 174 million jobs.

However, shipping—which carries over 80 percent of global trade—and offshore oil and gas production continue to contribute significantly to emissions and environmental degradation.

Governance and Knowledge Gaps Persist

Ocean governance is expanding, but 57 international treaties have created a fragmented system.

Sustainable management requires stronger cooperation and the inclusion of Indigenous knowledge and practices. Without this, achieving equitable and effective ocean protection will remain difficult.

Major knowledge gaps also remain: only 27 percent of the seafloor has been mapped as of 2025.

Solutions Exist, but Time Is Limited

Nature-based solutions, emissions reductions, and expanded marine protection offer pathways forward.

However, even full ecosystem restoration would contribute only about 2 percent of global climate mitigation needs, highlighting the necessity of broader systemic change.

The coming decade is critical. Without urgent and coordinated global action, ocean decline will continue—threatening climate stability, biodiversity, food security, livelihoods, and the wellbeing of billions worldwide.