The simple answer to whether ocean exploration is still happening is yes, and it is more active and technologically sophisticated than ever before. The global ocean covers over 70% of the planet’s surface, regulating climate and sustaining biodiversity. Despite its immense importance, large portions of the marine world remain unmapped and unexamined, representing the most extensive unexplored area on Earth. The collective effort across governments, private entities, and academic institutions is currently focused on leveraging new technologies to close this significant gap in knowledge.
The Vast Unknown
The scale of the unknown ocean is vast; it is often noted that we have better maps of Mars than of our own seafloor. Bathymetric mapping, the underwater equivalent of topography, has only been completed to high-resolution standards for approximately 26.1% of the global seabed. This leaves nearly three-quarters of the ocean floor still waiting to be accurately charted, a goal that international projects like Seabed 2030 are working to achieve by the end of the decade.
The lack of knowledge extends beyond the bottom, as the water column is also largely unsampled. The deep ocean, defined as the region below 200 meters, makes up over 90% of the entire living space on Earth. Less than 0.001% of the deep seafloor has been visually explored, meaning human eyes or cameras have only seen an area roughly the size of a small U.S. state.
The mesopelagic and bathypelagic zones, the mid-water regions, constitute a colossal volume of approximately one billion cubic kilometers. These zones are home to an estimated two-thirds of all ocean species, most of which are yet to be discovered or formally described. This immense reservoir of unexplored space means current exploration focuses as much on the water itself as on the seabed below.
Technologies Driving Discovery
The resurgence in ocean exploration is driven by new robotic and sensing technologies that withstand the crushing pressures and darkness of the deep. Autonomous Underwater Vehicles (AUVs) are untethered, self-propelled robots that navigate on pre-programmed missions without real-time human control. Since they are not limited by a physical cable, AUVs are highly effective for wide-area surveys and can dive to depths exceeding 6,000 meters to collect data over long periods.
In contrast, Remotely Operated Vehicles (ROVs) are connected to a surface ship by a fiber optic cable, or umbilical, which provides continuous power and allows for real-time control. This tether enables operators to execute precise tasks, such as collecting delicate biological samples, deploying scientific instruments, and manipulating objects with robotic arms. ROVs are the primary tools used for visual confirmation and detailed sampling once a promising area has been identified.
For broad-scale mapping, multibeam sonar systems mounted on research vessels transmit fan-shaped arrays of acoustic waves across the seafloor. By measuring the time it takes for these sound waves to reflect and return, the systems use beamforming to create high-resolution bathymetric maps. Satellite altimetry plays a supporting role for general, low-resolution global mapping by measuring subtle bulges and depressions on the sea surface. These minute variations are caused by the gravitational pull of massive underwater features, providing a preliminary understanding of the underlying topography.
New Frontiers of Exploration
Modern exploration targets specific, extreme environments that are changing our understanding of life and geology.
The Hadal Zone
The Hadal zone comprises the ocean’s deepest trenches, plunging from 6,000 to 11,000 meters, defined by pressure over 1,100 times that at the surface. Specialized life forms, such as giant amphipods and the deepest-dwelling snailfish, have evolved unique physiological adaptations to survive these conditions. These organisms often show high levels of endemism due to the isolation of the trenches, making them unique laboratories for evolutionary study.
Hydrothermal Vents
Hydrothermal vent ecosystems, typically found along mid-ocean ridges, are oases of life supported by chemosynthesis rather than sunlight. Superheated water emerges from the seafloor, carrying minerals that fuel dense communities of tube worms, snails, and microbes. Discoveries show that life also thrives in interconnected cavities and cracks beneath the seafloor, sustained by the mixing of cold seawater and chemical-rich vent fluid.
The Twilight Zone
The “Twilight Zone,” or mesopelagic zone, is the vast layer extending from 200 meters down to 1,000 meters, where only faint sunlight penetrates. This low-light environment is home to a massive biomass of organisms, including bristlemouths and bioluminescent jellyfish. The daily vertical migration of these creatures to feed near the surface and retreat into the depths is the largest animal migration on Earth and plays a major part in the ocean’s carbon sequestration processes.
Why Ocean Exploration Still Matters
The ongoing effort to explore the ocean is directly tied to humanity’s future well-being. The ocean is a primary regulator of the global climate, absorbing roughly a quarter of the anthropogenic carbon dioxide and over 90% of the excess heat generated by greenhouse gas emissions. Understanding deep-sea currents and the biological carbon pump—the process where sinking organic matter sequesters carbon in the deep ocean and seafloor sediments—is necessary to accurately predict future climate scenarios.
Marine organisms living in extreme environments represent an untapped resource for biomedical science. Deep-sea microbes and invertebrates produce unique bioactive compounds that enable their survival under intense pressure, darkness, or high heat. These compounds are being investigated for potential use in novel medical therapies, including new antibiotics and anti-cancer drugs.
Exploration also provides foundational data for global resource management. Detailed seafloor maps inform the sustainable siting of offshore infrastructure, such as wind farms and deep-sea mining operations. Mapping the distribution and behavior of deep-sea life is necessary to establish baselines for biodiversity protection and to assess the impact of human activities on these globally important ecosystems.