Is Most of the Ocean Unmapped and Unexplored?

How much of the ocean has been mapped and explored?

Check out this answer from Consensus:

The ocean remains a largely uncharted territory, with only a fraction of its vast expanse mapped and explored. Recent efforts, such as the NOAA CAPSTONE expedition, have provided valuable insights and laid the groundwork for future exploration. As technology continues to advance, the potential for new discoveries and a deeper understanding of the ocean’s mysteries grows, promising exciting opportunities for scientific research and ecological understanding.

The ocean, covering over 70% of the Earth’s surface, remains one of the least explored frontiers. Despite technological advancements, a significant portion of the ocean floor remains uncharted. This article delves into the current state of ocean mapping and exploration, highlighting recent efforts and the challenges that lie ahead.

Current State of Ocean Mapping

Modern ocean mapping techniques have significantly evolved over the past few decades. According to a review of deep seafloor mapping systems, advancements from 1976 to 1986 have revolutionized deep ocean surveys, allowing for detailed sonar imagery and bathymetry with real-time mapping displays2. These technologies have enabled researchers to investigate large areas of the seafloor with unprecedented detail.

Recent Efforts in Ocean Exploration

One of the most comprehensive recent efforts in ocean mapping was the NOAA CAPSTONE (Campaign to Address Pacific monument Science, Technology, and Ocean NEeds) expedition. Over a three-year period, NOAA mapped 597,230 km² of the Pacific seafloor, with approximately 61% of this area located within US waters. This effort included the mapping of 323 seamounts and conducting 187 ROV (Remotely Operated Vehicle) dives, which provided 189 hours of benthic imaging time1.

Insights from CAPSTONE

The CAPSTONE expedition yielded significant insights into the biodiversity of the Pacific deep-sea. Despite the extensive mapping, fewer than 20% of the species visualized with the ROV could be identified. The most abundant and diverse taxa observed were from the classes Anthozoa, Porifera, and Echinodermata. The expedition also documented over 347,000 individual organisms, revealing novel taxa, records, and behaviors suggestive of new species interactions and drivers of community composition1.

Extent of Mapped Ocean

To date, only 13.8% of the Pacific Ocean has been mapped using modern methods. This statistic underscores the vastness of the unexplored ocean and the need for continued efforts in ocean mapping and exploration. The CAPSTONE expedition, while extensive, marks the beginning of a new era in ocean exploration, offering extensive opportunities for future research through advanced mapping, technology, and analysis1.

Is most of the ocean unmapped and unexplored?

Martine Lizotte has answered Near Certain

An expert from Université Laval in Oceanography

Yes. While the ocean’s surface is probed and analyzed in situ during oceanographic research campaigns or remotely-sensed via satellites on a continual basis, the vast majority of the underlying body of water remains unobserved, unmapped and unexplored. While estimating the actual percentage is challenging and a matter of debate, the National Oceanic and Atmospheric Administration (NOAA) suggests that more than 80% of the oceans remain unexplored to this day. This is explained by the challenging environmental conditions (particularly high pressures at depth) and tremendous costs associated with the exploration of the deeper oceanic realm. The advent of modern sonar technologies that help in mapping the seafloor and the use of remotely operated vehicles (ROV) or autonomous underwater vehicles (AUV) that scan the water column has increased our observations. The international ARGO program, consisting of a fleet of robotic instruments that drift with the ocean currents and move up and down between the surface and the first 2000 m of the water column, has also led to a greater spatial and temporal coverage of oceanic waters. In a sense, oceans represent the great frontier for the next generation of explorers and researchers, where vast opportunities for inquiry and investigation remain.

Is most of the ocean unmapped and unexplored?

Robert  Steneck has answered Likely

An expert from University of Maine in Oceanography, Marine Biology

No and yes. Mapping with multibeam sonar etc covers much of the world’s oceans. However, most of the worlds oceans have never been seen or studied by humans.

Is most of the ocean unmapped and unexplored?

Megan Cook has answered Near Certain

An expert from Ocean Exploration Trust in Oceanography

Yes, most of the ocean remains unexplored and unmapped at high resolution. Today only 20% of oceans deeper than 200 meters are mapped in high-resolution (for more info and annual updates visit GEBCO Seabed 2030 Project) And less than 5% of oceans have been visually surveyed due largely to the scale of the ocean. The average ocean depth is around 3.9 km or almost 13,000 feet.  Scientists agree that most deep-sea animals are yet-to-be-discovered.

Is most of the ocean unmapped and unexplored?

Is most of the ocean unmapped and unexplored?

Jessica Meeuwig has answered Likely

An expert from University of Western Australia in Ecology, Marine Science

As of 2021, less than ten percent of the global ocean has been mapped using modern sonar technology. Most of what is mapped is also near shore and in relatively shallow waters (<200 m). To quote marine biologist Professor Paul Snelgrove “we know more about the surface of the Moon and about Mars than we do about the deep sea floor despite the fact that we have yet to extract a gram of food, a breath of oxygen or a drop of water from those bodies”. Ocean exploration is critical ensuring a resilient and healthy ocean. 

Is most of the ocean unmapped and unexplored?

Douglas Fenner has answered Uncertain

An expert from National Oceanic and Atmospheric Administration in Marine Biology

This is frequently stated in the popular press, and even by some projects to map the ocean floor. The facts include the fact that modern satellites can map the ocean floors and have done so EVERYWHERE. They can do it by measuring the height of the ocean (probably with radar). When there is an undersea mountain, that mountain has mass that gravitationally attracts water, making the water surface just slightly higher above the mountain. The opposite is true of trenches. And the height of sea floor in between those can and has all been mapped. The other way is that there are a pair of satellites which are in the same orbit, with one a ways ahead of the other. They measure the distance between them with great accuracy (maybe with a laser?). When one of them goes over an increase in mass, it speeds up slightly, widening the distance between them, and when the second one goes over it then it speeds up decreasing the distance between them. They are so sensitive they can record and map underwater aquifers on land and determine how much water there is in them.

The more traditional way to measure and map the seafloor is by sonar. A ship sends out “ping” sounds as it moves along, and records the time it takes for the ping to bounce off the floor and return. That produces a detailed map of the bottom. Originally they used a single sound source in a single beam. Now they do “mulitbeam” sonar, at least in shallow water. This has greater resolution than the satellites, but it can only cover where the ship is. Some ships leave their sonar running as they go about their business steaming to different places. If you look at Google maps, and magnify the image of seafloor, you will see stripes of sharper resolution where ships have gone.

So the entire earth seafloor has had its depth mapped, but at lower resolution, and people are continuing to map it by ship at higher resolution. So while the entire seafloor has been mapped at lower resolution, only part of it at higher resolution.

And that is just for depth. The magnetic signature in the seafloor crust of the earth has been mapped in some areas. That is done by towing a sensitive magnetic sensor near the seafloor. Data from that was the first convincing evidence of “continental drift” now called “plate tectonics.” But the entire seafloor has probably not been mapped for that.

Biological mapping, such as by trawling, or by mud “grabs” or sediment mapping with sediment cores, can only map very small points or areas, so has not been done everywhere. Likewise, imaging life on the seafloor requires putting down cameras and can only be done in very small areas. Plus, at great depths, it is difficult to make camera housings that can withstand the pressures.

So all the sea floor has had at least low resolution mapping of depths, but mapping of depths at higher resolution, and other kinds of mapping and exploration have only been done in very small areas.