12 ways humans depend on the ocean

1. Regulating climate and weather

Without the ocean’s processes and ecosystems, extreme weather would be far more severe and widespread problem.

The ocean is our most powerful climate regulator. It absorbs, stores, and redistributes heat across the globe. Vast currents, such as the Gulf Stream, take warm water from the equator toward the poles, while cooler waters move back toward the tropics.

This circulation evens out global temperatures and shapes regional climates. You can think of the ocean as a global delivery system for heat, constantly transporting warm and cold water to where it is needed, keeping the planet’s climate in check.

The ocean also acts as a defense system against natural disasters. Healthy ecosystems such as mangroves, coral reefs, and wetlands absorb wave energy, reduce coastal erosion, and minimize flooding during storms and hurricanes.

Coral reefs can lower the impact of storm surges on vulnerable communities. While wetlands and marshes add further protection by storing excess water to protect against floods.

2. Providing oxygen

Oxygen comes from trees, right?

Well, it does. But did you know most of the oxygen we breathe is produced by photosynthesis taking place in the ocean?

Tiny marine plants called phytoplankton generate at least half of Earth’s oxygen, which is more than all the world’s rainforests combined. They absorb carbon dioxide and sunlight, releasing oxygen into the atmosphere. Other ocean plants such as seaweed, kelp forests, and seagrasses also produce oxygen, especially along coastlines.

The ocean is our planet’s largest oxygen factory, making life on Earth possible.

3. Supplying food

Nearly three billion people rely on seafood as a key source of protein, underlining the ocean’s vital role in global nutrition.

Fisheries and aquaculture are a part of this dependence on the ocean, harvesting and cultivating marine species to meet growing demand and ease pressure on wild fish stocks.

Marine plants like seaweed and algae also play a key role. They are rich in vitamins, minerals, and proteins and serve as dietary staples in many cultures. Beyond direct consumption, they’re widely used in supplements and food ingredients.

4. Supplying fresh water (indirectly)

Even though we can’t drink it directly, the ocean quietly supplies most of the freshwater we depend on through the water cycle.

When heated by sunlight, ocean water evaporates. The vapor rises, cools, and condenses into clouds that eventually release rain, snow, or sleet. It’s this precipitation that replenishes rivers, lakes, groundwater, and glaciers on land.

Ocean currents and temperatures also shape global rainfall patterns, influencing how freshwater is distributed and available around the world.

5. Fueling the economy

The ocean fuels the global economy, generating trillions of dollars every year and sustaining millions of jobs worldwide. From shipping and tourism to fisheries and renewable energy, ocean-based industries are crucial to economic prosperity.

Coastal tourism and recreation also bring huge economic value, while fisheries and aquaculture sustain hundreds of millions of people through food and employment.

In addition, the ocean provides vast natural resources, ranging from renewable energy to supplies for marine ingredients used in medicine, cosmetics, and biotechnology.

These ocean activities form the “Blue Economy,” an important part of generating wealth, resilience, and growth worldwide.

6. Recreational and cultural value

Beaches, surfing, sailing, diving, and marine parks bring joy to people around the world. The ocean supports a vibrant tourism industry.

In many regions tourism really drives local economies through activities like scuba diving and whale watching.

Beyond economics, ocean-based recreation promotes health by offering physical activity, stress relief, and mental restoration.

For many communities, the ocean is a core part of cultural identity and heritage with rich traditions tied to the sea. The ocean has inspired art, literature, music, and film across generations.

The ocean enriches human life far beyond its ecological and economic roles.

7. Transportation and trade

Marine transportation is the backbone of international commerce. Around 80 to 90% of global trade moves by sea, according to the United Nations and the International Maritime Organization.

Maritime shipping is often the most efficient and cost-effective way to move goods across the world. Ships can carry far greater volumes of cargo than air, road, or rail. It allows us to transport oil, grain, minerals, and manufactured products on a massive scale.

The ocean helps to keep goods affordable and directly supports millions of jobs through ports and shipping industries.

8. Carbon storage (carbon sink)

By storing carbon on an enormous scale, the ocean stabilizes global climate systems and mitigates the effects of global warming.

The ocean absorbs roughly 25–30% of human-generated CO₂ emissions, making it one of Earth’s most critical carbon sinks.

Carbon dioxide dissolves into seawater and is carried by ocean currents into deeper layers, where marine life and chemical processes lock it away for centuries or longer. This natural process slows the pace of climate change by reducing greenhouse gases in the atmosphere.

9. Energy resource

The ocean is a powerful source of renewable and non-renewable energy, making it essential in meeting energy demands.

Beneath the seabed, oil and natural gas provide a significant share of the world’s supply, though their extraction carries environmental risks and contributes to climate change.

At the same time, the ocean offers vast potential for clean, renewable energy. Offshore wind farms harness strong, steady winds to generate electricity, while wave and tidal energy technologies convert the movement of the sea into power.

In tropical regions, Ocean Thermal Energy Conversion (OTEC) can even produce electricity by using temperature differences between warm surface waters and cooler deep waters.

10. Source of medicine

The ocean is a promising source of future medicines, with its vast biodiversity offering unique compounds that could transform healthcare.

Coral reefs, deep-sea ecosystems, algae, sponges, bacteria, and corals all produce bioactive substances with antiviral, antibacterial, antifungal, and anticancer properties.

While most medicines today are not derived from the ocean, scientific exploration continues to reveal its untapped pharmaceutical potential.

A few marine discoveries have already made an impact, such as cancer drugs developed from sponges, powerful painkillers inspired by cone snail toxins, and anti-inflammatory compounds from algae.

With greater exploration and research, marine-derived pharmaceuticals could provide breakthroughs in treating disease and improving health.

11. Critical infrastructure

The ocean underpins much of the world’s critical infrastructure. It is the foundation for global communication, energy, and transportation systems.

Submarine cables laid across the seafloor carry over 95% of international data traffic, making modern internet, financial transactions, and digital communications possible.

Ports and shipping lanes also connect countries through trade, ensuring the flow of raw materials, manufactured goods, and essential supplies worldwide.

Offshore infrastructure supports energy security. Oil and gas platforms, offshore wind farms, and emerging renewable projects like tidal and wave power rely on the ocean for location and operation.

Human society depends on the ocean not only for resources but also for the infrastructure that sustains daily life.

12. Influencing global biodiversity

Healthy oceans are essential to maintaining global biodiversity.

The ocean contains the majority of all life on Earth. From coral reefs and mangroves to the deep sea, these ecosystems provide critical habitats that sustain life ranging from microscopic plankton to the largest mammals on the planet.

What’s particularly exciting is how many marine species remain undiscovered, holding immense potential for science and medicine.

How DEEP’s work will impact our relationship with the ocean

Conserving the ocean is essential for sustaining biodiversity, regulating climate, and protecting the livelihoods of people worldwide.

Yet effective conservation depends on knowledge. We need to understand how marine ecosystems function, how species interact, and how environmental stressors affect these delicate systems.

The more we uncover about the ocean, the better equipped we are to safeguard critical habitats, manage resources sustainably, and mitigate threats through policy.

DEEP is investing in advancing this understanding through the development of subsea human habitats. Unlike short dives or remote exploration, these habitats will give scientists the ability to live and work underwater for extended periods, observing marine life in its natural state and gathering real-time data.

Follow the journey

Stay updated on DEEP’s progress by following us on social media @deepengineered and visiting our Newsroom.