Tucked inside a federal government building in the American Rockies is the world’s best collection of seafloor maps. Occasionally a hard drive arrives in the mail, filled with new bathymetric – or seafloor – charts collected by survey vessels and research ships cruising the seas. The world’s largest public map of Earth’s oceans grows just a little bit larger.
The seafloor has resisted human exploration for centuries, for obvious reasons. Folklore and myths told of it being the domain of terrifying sea monsters, gods, goddesses and lost underwater cities. Victorian-era sailors believed that there was no ocean floor at all, just an infinite abyss where the bodies of drowned sailors came to rest in watery purgatory.
Throughout the last century, modern scientific techniques, and sonar, have dispelled those stories, and revealed a little-understood seascape of crusted brine lakes, steaming volcanoes, and vast undulating underwater plains. We have only just begun to map, much less explore, this enormous sub-sea world.
One organisation wants to change this – and quickly. In 2023, Seabed 2030 announced that its latest map of the entire seafloor is nearly 25% complete. The data to make the world’s first publicly available map is stored at the International Hydrography Organization (IHO)’s Data Centre for Digital Bathymetry (DCDB) in a government building in Boulder, Colorado.
One of the reasons I found this information interesting is that I live in Boulder and have never heard of this organization or the building where the maps are apparently stored……and the city is not that big. I will investigate.
So far, the DCDB holds over 40 compressed terabytes of seafloor data. The biggest contributor is the US academic fleet: 17 research vessels owned by American universities which constantly circle the globe studying the deep ocean. Other contributors include the National Oceanic and Atmospheric Administration (NOAA) fleet, the Geological Survey of Ireland, and Germany’s Federal Maritime and Hydrographic Agency. The biggest users are scientists all over the world who rely on the data to conduct research.
Seabed 2030 has made extraordinary progress by asking countries and corporations to share maps with the DCDB. But unfortunately, the overall map is not growing quickly enough. Between 2016 and 2021, the map leapfrogged from 6% to 20% of the ocean floor. Since then, the pace has slowed. In 2022, it reached just 23.3% complete; in 2023, 24.9%. The ocean mappers had to come up with a new plan: They did, and they called it “Crowdsourcing”.
Crowdsourced bathymetry came about when the IHO was saying: “At this rate, we’re never going to map the whole darn ocean; we need to start looking outside the box,” says Jennifer Jencks, the director of the DCDB, and the chair of a crowdsourced working group at the IHO. By attaching a data logger to a boat’s echosounder, any vessel can build a simple map of the seafloor. This is crucial in developing coastal and island nations. However, there’s a roadblock when it comes to sharing maps with the DCDB archive back in Boulder.
Despite Seabed 2030’s publicly stated scientific goal, the military or commercial value of nautical charts will always be a barrier to achieving complete coverage of the world. “Sea charts, by their very nature, were destined to be removed from the academic realm, and from general circulation,” wrote the map historian Lloyd Brown in his book The Story of Maps. “They were much more than an aid to navigation; they were in effect, the key to empire, the way to wealth.”
In many instances they still are, even though those seeking empires, and seafloor resources, have changed. It used to be Britain, Spain and Portugal seeking empire, now it’s China seeking territorial gains and ocean-bed resources. In fact, seafloor resources, unknown and inaccessible until recently, have become a “land-grab” international race.
In a world where only a quarter of the seafloor is charted, there’s still an advantage in knowing more than your rivals. Niwa’s Mackay experienced this himself on a scientific-mapping expedition. (NIWA is New Zealand’s National Institute of Water and Atmospheric Research). He received a call from a military he chooses not to name and “they said ‘you need to destroy that data because there was military value in what you’re mapping, because it’s a place where submarines like to hide’,” he recalls. “Obviously, we ignore them because we’re [mapping] for science, we don’t care. But the military, they find lots of value in bathymetry that, as a scientist, we don’t even think about.”
For some nations, it’s also suspicious that the DCDB is based in the United States, which has the world’s most powerful military. “We have seen concerns that the DCDB is hosted by the United States. Not everyone loves that,” says Jencks. She tries to assuage these concerns by stressing that the DCDB was endorsed by all IHO member states back when it was created in 1990.
With just over six years left until the deadline of completion, Seabed 2030 faces serious challenges in finishing the first public map of the seafloor. The staggering size of the ocean, the depths, the hostile offshore working environment, where ocean mappers are constantly contending with wind, waves, and the corrosive effects of salt water are just some of reasons for this skepticism. Then there’s the cost of mapping remote international waters where no country has jurisdiction.
However, all these challenges seem small compared to the work of uniting countries behind a collective goal. Unfortunately, those country’s differences in ambitions can explain why the goal of finishing a complete map of the seafloor may remain out of reach for many decades to come.