Why the health of our oceans is vital to us


Madeline Hodge, Lead Sustainability Advisor, Ørsted

The first time I donned a scuba kit, I was captured by the stunning marine life, the shimmering colours, and the peaceful tranquillity that came from being 20 metres under the sea surface. And as a former oceanography and coastal management student, I knew there was a lot more than meets the eye.

From the microscopic species to the largest mammal on the planet, from the deep dark depths to the brightly coloured coral shallows, and from the freezing to the tropical waters – our oceans are essential to life on Earth. In fact, they host 80 percent of the planet’s biodiversity, and this variety is the cornerstone of the ocean’s vital role in regulating our planet’s climate.

Unfortunately, human activity threatens our oceans. Overfishing, pollution, and the global temperature rise are adversely affecting the survival of marine species, while coastal development is destroying important marine ecosystems, including coral reefs, seagrass meadows, mangroves, and salt marshes.

A future in which humanity thrives hinges on clean, healthy, and biologically diverse oceans.


From environmental services, such as carbon sequestration, to providing sustainable and healthy food sources, here are five overlooked areas where oceans are supporting us:

  1. Vital source of food and income.
    As the largest ecosystem on Earth, the ocean provides 20 % of animal protein to around 3 billion people, while millions rely on income from fishing and fish farming jobs.

  2. Climate regulation. 
    As one of the world’s largest carbon sinks, the ocean acts like a global climate control system. It absorbs and stores at least a quarter of all carbon dioxide that human activity puts into the atmosphere, helping mitigate climate change and limit global warming.

  3. Flood risk protection. 
    Coastal ecosystems, such as mangroves, are critical to climate adaptation and resilience for local communities. For instance, research shows that salt marshes help protect our coasts by stabilising shorelines and protecting them from damage by incoming waves. These benefits are particularly significant in light of the devastating impact of storms and flooding, which are likely to increase with climate change.

  4. Health research.
    Marine invertebrates produce more antibiotic, anti-cancer, and anti-inflammatory substances than any group of terrestrial organisms and represent an invaluable asset for pharmaceutical research.

  5. Renewable energy.
    With the global installed offshore wind capacity expected to reach 630 GW) by 2050, up from 40 GW in 2020, the oceans represent a breakthrough for the energy transition – one that must be thought in balance with nature and biodiversity.

These are five ways that the ocean supports us. So, what are we doing to support the ocean? The fifth point – renewable energy, specifically offshore wind – is where we believe we can play a key role. Ørsted aims to create net-positive impact on biodiversity with all new renewable energy projects commissioned from 2030.

‘Net-positive’ means that we are going beyond mitigating any potential negative effects we have on marine habitats and species by developing projects that will outweigh the impact on natural ecosystems and seek to leave nature in a better state than we found it. One example of this would be installing artificial reef structures to increase habitat complexity, providing homes for cod and other marine fauna, and enhancing the marine food web

Addressing climate change requires an unprecedented effort, but nature provides us with all the solutions we need – from wind and sun to the mighty oceans. By creating the conditions for nature to thrive, we can nurture healthy, biodiverse oceans and ensure they can keep supporting life on Earth, not to mention the beauty that so many of us divers love.