Ocean Risk

The ocean is vital for supporting life on our planet.
It is also a significant source of goods and services to the world economy.

But our ocean is changing faster today than at any time in human history. Ocean warming, rising sea levels, acidification, marine pollution and habitat destruction are all creating greater risk and uncertainty, with wide-ranging implications for coastal communities, infrastructure, biodiversity and the lives and livelihoods of billions of people.

Sea level and population density projections indicate that 800 million people will be at risk of coastal flooding and storm surges by 2050. Communities in developing countries and Small Island Developing States (SIDS) are the most threatened, with women and girls especially hard hit.

The costs of ocean-related hazards are also mounting. It is now estimated that by 2050, the global community will face annual costs of over $1 trillion to coastal urban areas as a result of the combined effects of rising sea levels and extreme weather events on our coastlines.

Ocean-derived risk can be categorised into three risk trends:


Immediate onset risks:

  • Tropical cyclones
  • Storm surge events
  • Flooding and inundation

Slow onset risks:

  • Sea-level rise
  • Acidification
  • Food security issues
  • Impacts on human health
  • Declines in biodiversity

Risk Multipliers:

  • Pollution
  • Resource exploitation (including overfishing)
  • Land-use change

There is an urgent need to better understand and mitigate ocean-derived risks, and build the resilience of coastal natural capital. Investing in nature-based solutions is a key part of protecting the most vulnerable communities and regenerating biodiversity, specifically through valuing and protecting coastal ecosystems which are critical natural assets for reducing disaster impacts. ORRAA’s work is dedicated to this.

40% of the world's population live in coastal areas.


In the last 30 years, the amount of the world’s GDP annually exposed to tropical cyclones has increased by more than US$1.5 trillion.


Over US$300bn have been paid by insurers over the last 10 years for coastal storm damage, with significantly larger costs being borne by governments and taxpayers.

Mangrove forests provide more than US$80 billion per year in avoided losses from coastal flooding – and protect 18 million people. Without mangroves, 39% more people would be flooded anually.

Just 100 metres of mangroves can reduce wave height by 66%. Mangrove forests sequester five to ten times more carbon from the atmosphere than terrestrial forests.

Nearly 200 million people depend on coral reefs to help protect them from storm surges and waves. Reefs reduce the annual expected damages from storms by more than US$4 billion.