Only a Tiny Fraction of Deep Seafloor Mapped Over Seven Decades

The study, titled "How Little We've Seen: A Visual Coverage Estimate of the Deep Seafloor," represents the most comprehensive estimate of deep-sea visual coverage to date, highlighting the profound knowledge gaps that still exist in our understanding of this vast ecosystem.

The deep ocean, defined as regions deeper than 200 meters, plays a vital role in global climate regulation, oxygen production, and pharmaceutical discoveries, yet remains one of the least explored environments on the planet. The research, based on data from roughly 44,000 deep-sea dives conducted since 1958 across the waters of 120 countries, underscores the limited reach of current oceanographic exploration. Even if current estimates are off by a full order of magnitude, less than 0.01% of the seafloor has been captured in visual records.

Dr. Katy Croff Bell, President of Ocean Discovery League and National Geographic Explorer, emphasized the importance of expanding deep-sea research in light of the growing pressures from climate change, resource extraction, and potential mining.

"As we face accelerated threats to the deep ocean-from climate change to potential mining and resource exploitation-this limited exploration of such a vast region becomes a critical problem for both science and policy," she said. "We need a much better understanding of the deep ocean's ecosystems and processes to make informed decisions about resource management and conservation."

The study also revealed that the majority of these visual observations are concentrated within the territorial waters of just a few nations. Over 65% of documented deep-sea dives occurred within 200 nautical miles of the United States, Japan, and New Zealand, with five countries alone- the United States, Japan, New Zealand, France, and Germany-accounting for 97% of all submergence data. This geographic concentration reflects the high costs associated with deep-sea exploration, which has traditionally limited participation to wealthier nations.

The research further highlights the uneven distribution of studies across different seafloor types. While features like canyons and ridges have been more thoroughly investigated, vast regions such as abyssal plains and seamounts remain largely unexplored, presenting a significant gap in global seafloor knowledge.

To address these challenges, the researchers are calling for expanded international collaboration and the use of emerging technologies to lower the barriers to deep-sea exploration. Dr. Ian Miller, Chief Science and Innovation Officer at the National Geographic Society, which provided funding for the study, noted the critical role of local communities in advancing this work.

"Deep-sea exploration led by scientists and local communities is crucial to better understanding the planet's largest ecosystem," he said. "Dr. Bell's goals to equip global coastal communities with cutting-edge research and technology will ensure a more representative analysis of the deep sea. If we have a better understanding of our ocean, we are better able to conserve and protect it."

This groundbreaking research underscores the urgent need for a more comprehensive and globally inclusive approach to deep-sea exploration, with the hope of fostering a more accurate and complete understanding of our planet's largest and most mysterious ecosystem.

Research Report:How Little We've Seen: A Visual Coverage Estimate of the Deep Seafloor