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 more.
Cloaked in ocean, the seafloor has resisted human exploration for centuries. Folklore and myths told of it as 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 the 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 subsea world.
The Victoiran era saw a massive effort to chart the world’s oceans, but many areas have seen minimal mapping since (Credit: Getty Images)
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.