It can be seen that over the two-thirds of the surface of the planet, there is less than 0.001% of the deep ocean seafloor, which although much larger than Rhode Island, has been directly imaged.
This imbalance is not only a historical curiosity of exploration. It is an information and engineering issue that is enacted in the fields of climate modeling, biodiversity science, and the creation of regulations of industrial activity in the far offshore. It is more difficult when the seabed is less than 200 meters deep, and light disappears and the sea becomes a place of cold, pressure, and economic impossibility. But the deep ocean floor serves to balance the earth systems such as long-term carbon storage, and it supports ecosystems that are not similar to the sunlit ocean in the minds of most people.
The deep seafloor less than 0.001 percent estimate is based on a database constructed after 43,681 records of deep-sea dives which had optical imaging (since 1958). Two complementary methods were used by researchers based on the paths traversed along the bottom and time spent in the sea bottom to bracket the extent of the terrain actually observed. The outcome is a slender strip of a long and expansive scenery: approximately 822 to 1, 476 square miles of seabed visually recorded.
Even such a small sample is not evenly distributed. Over 65 percent of visual observations made and 97 percent of deep-sea submergence observations made were made within 200 nautical miles of coasts of the United States, Japan or New Zealand, and 5 countries made 97 percent of the recorded visuals observations and 97 percent of the deep-sea submergence observations (United States, Japan, New Zealand, France, and Germany). Practically, the known locations of the deep ocean are where vehicles, ships, funding and archives already are.
The second bias is concealed in the landscape. The characters of dramas like ridges, canyons, vents, are drawings to cameras since they appear like destinations. The abyssal plains with numerous seamounts that take up vast space are relatively unexplored. The implication is rather oblique yet important: conclusions regarding deep-sea conditions in the world are made based on recurrent visits to a limited number of visually interesting locations.
Mapping fails to fill that gap, but alters the locations of cameras. By June 2025, 27.3% of the total seafloor would be mapped using current high-resolution technology, including multibeam sonar mounted on ships. Those maps indicate form ridges, slopes, scars, seamount shapes but not species, behaviors and ecological relationships. A map may indicate the probable habitat in which the vehicle should head; it does not say what inhabit it or how the communities react to the invasion.
The difference is important as the deep seabed images are gradually becoming the baseline evidence of impact assessment. Deep-sea mining plans are directed to the areas of mined materials deep-sea fields, over abyssal plains, and hydrothermal vents, although scientific descriptions of these areas are still incomplete. The gap in knowledge is not just the finding of strange things; it is the creating representative conditions before in places which might be changed more rapidly than they can be revisited.
It was researchers who were engaged in deep-seafloor estimation that framed the situation in a straightforward manner. With increasing threats to the deep ocean, including climate change, possible mining and resources exploitation, this relatively little exploration of such a large area is becoming a pressing issue both scientifically and in policy making, as Dr. Katy Croff Bell explained. Scientist and local communities should explore deep seas, as Ian Miller contributed: Better knowledge of the biggest ecosystem on the planet is possible thanks to the exploration.
What is revealed is a contemporary limitation that is antique in nature: the majority of the greatest habitat of the planet is beyond the daily human perspective. The subsequent advantages lie not so much in heroic plunges as in the broadening of access to imaging devices, creating access to data archives and sharing exploration, not just a few along the coastline.
