The ocean covers over 70% of Earth’s surface and holds 97% of its water. It profoundly shapes our planet, influencing air, food, and the global economy. Its depths harbor diverse life and resources, many undiscovered. Understanding its influence reveals its connection to human existence and planetary well-being.
Global Life Support Systems
The ocean regulates Earth’s atmosphere, climate, and water cycles, driving essential planetary processes. Changes in the ocean affect life widely.
Microscopic phytoplankton produce a substantial portion of Earth’s atmospheric oxygen. These tiny photosynthetic organisms, including algae and bacteria, generate half of the planet’s oxygen. One species, Prochlorococcus, contributes up to 20% of the oxygen in our biosphere.
The ocean regulates global temperatures by absorbing and distributing vast solar radiation. It has absorbed over 90% of excess heat from human activities since 1955. This moderates atmospheric warming, preventing rapid temperature increases on land. Its top few meters can hold more energy than Earth’s entire atmosphere.
Ocean currents act as a global conveyor belt, transporting warm water from the equator toward the poles and cold water back to the tropics. This movement distributes heat and moisture globally, regulating climates and preventing harsh conditions. Without these currents, many areas would experience harsher conditions.
The ocean is central to the global water cycle. Approximately 86% of global evaporation originates from the ocean, and 77% of surface rainfall occurs over its surface. Evaporating water forms clouds that release precipitation over land and sea. This cycle replenishes freshwater sources and maintains ecological balance.
Biodiversity and Essential Resources
The ocean houses an immense, largely unexplored diversity of species. This rich biodiversity provides many resources, benefiting human societies.
Marine ecosystems support a vast variety of organisms, many yet to be discovered. This includes microscopic bacteria, coral reefs, and deep-sea creatures. Continued exploration reveals new life forms and unique adaptations.
The ocean serves as a major protein source for billions worldwide. Fisheries and aquaculture provide a significant portion of the global food supply, supporting livelihoods and nutrition in many coastal and island nations. Seafood remains a staple, vital for global food security.
Marine organisms are a promising source for new pharmaceutical compounds and biomedical research. Substances from marine invertebrates like sponges, tunicates, and cone snails can treat human diseases. For example, tunicate compounds are tested for breast and ovarian cancers, deep-sea sponge substances show anti-tumor properties, and cone snail venom yields a potent pain-killer.
Beyond medicinal uses, unique genetic material in marine organisms, especially from deep-sea environments, offers biotechnology potential. These organisms evolved distinct biochemical pathways to survive challenging conditions, leading to novel enzymes and compounds. Such genetic resources could advance various industrial and scientific fields.
Economic and Societal Contributions
The ocean provides substantial economic and societal benefits, supporting industries, trade, and human well-being. It facilitates global connectivity and offers opportunities for economic growth and employment.
Maritime transport forms the backbone of global trade, with 80% to 90% of internationally traded goods moved by sea. This includes raw materials, manufactured products, and energy resources, transported efficiently and cost-effectively. The global merchant fleet, approximately 100,000 ships, ensures the continuous flow of goods sustaining economies worldwide.
Coastal areas and marine environments are significant hubs for recreation and tourism, generating considerable economic activity. Activities like beach holidays, cruises, recreational fishing, and marine wildlife viewing attract millions annually. This sector supports numerous businesses and jobs, contributing to local and national economies.
The ocean holds substantial energy and mineral resources. Offshore oil and natural gas fields have been traditional energy sources. Renewable energy sources like offshore wind and tidal power are expanding rapidly, with global offshore wind capacity reaching 64.3 gigawatts in 2022. The seabed also contains valuable mineral deposits, including polymetallic manganese nodules and seafloor massive sulfides.
Ocean-related industries support millions of jobs globally across diverse sectors. These include shipbuilding, fishing, aquaculture, marine tourism, offshore energy, and scientific research. These economic activities provide livelihoods for coastal communities and contribute to the global workforce.