Steinar Ellefmo, an Associate Professor in NTNU’s Department of Geology and Mineral Resources Engineering, said: “We actually know more about the moon than the seafloor.” He’s not wrong. Since 1969, we have sent 12 people and many probes to the moon, but only three people have descended to the deepest part of the ocean, the Marianas Trench. According to the American National Oceanic and Atmospheric Administration (NOAA), 95% of the ocean remains unexplored. Now, however, scientists are racing to map the Earth’s seabed for the first time.
Mapping the seabed is critical for several reasons. For scientists, it helps to understand ocean currents and weather patterns. It also gives them valuable information about life in the sea, of which we have limited understanding. There’s also a commercial incentive – mapping the seabed can provide us with data on valuable minerals hidden in the seabed. Mapping can also help locate lost planes and sunken ships. Who knows, we might finally discover what happened to Amelia Earhart.
The ambitious project was born from the 2017 United Nations Ocean Conference when at the time, only 6% of the ocean had been mapped in accurate detail. In the three years since the Nippon Foundation-GEBCO Seabed 2030 Project has mapped 19% of the ocean. It is humanity’s best effort to date and is critical for not just scientists, but countless others who depend on the ocean for a living. It is, however, no easy task.
The Challenge of Mapping the Ocean
When it comes to mapping the stars, light is our best friend. Since it travels far and fast in the vacuum of space, light can be used to chart celestial bodies. Advances in engineering have also given us more powerful telescopes and probes, enabling us to see the mysteries of deep space. Light is, however, not a good friend in the oceans.
Since water absorbs light, it is impossible to use telescopes or other light-based techniques to explore the ocean’s depths. Sound, however, is an efficient alternative. Today, the standard for ocean mapping is a multibeam echosounder. The device sends down sound waves shaped like a fan, which computers then decipher into a three-dimensional portrait of the seafloor’s shape and the composition of the rock.
But it is not an easy task. As the Smithsonian Magazine put it: “to complete a map of Earth’s ocean floor, you’ve got to take to the high seas by boat.” And if we did that, “it would take a lone ship approximately 200 years to chart all 139.7 million square miles of ocean.” That’s not the only problem. It is easier to send a probe to space than to the depths of the ocean, because of pressure. According to the NOAA “the deeper you go under the sea, the greater the pressure of the water pushing down on you. For every 33 feet (10.06 meters) you go down, the pressure increases by one atmosphere.” Creating a probe that can withstand the extreme pressures of the ocean is a challenge of engineering that is both expensive and complicated.
Humanity has had some degree of success in that area. There have been two manned expeditions to the Marianas Trench, the deepest point in the ocean (at 10,984m) till date. The latest was by Hollywood director James Cameron aboard the Deepsea Challenger in 2012. So high was the pressure, that according to Cameron “the sphere that I was in actually shrank” and this was despite the advanced materials used to create the submersible. Nonetheless, those expeditions have shown that it’s possible to overcome the pressure of the deep ocean.
The massive project is a collaboration between the Alfred Wegener Institute in Germany (in charge of the Southern Ocean), Stockholm University and the University of New Hampshire (the North Pacific and Arctic), New Zealand’s National Institute of Water and Atmospheric Research (South and West Pacific Ocean), and the Lamont-Doherty Earth Observatory at Columbia University (Atlantic and Indian Oceans). All the data they collect and map is analysed and compiled by the British Oceanographic Data Centre in Southampton.
The team is backed by Japanese non-profit the Nippon Foundation, which contributes $2m every year. Mapping the seabed is critical to Japan, as it would improve Japan’s fisheries management and its tsunami and typhoon preparation, as well as clarify territorial claims in the South China Sea. All the data will be available in the public domain, free of cost through the General Bathymetric Chart of the Oceans (Gebco).
What makes this effort unique is that it aims to map the seabed at a very high resolution. According to How Stuff Works, right now we have mapped the ocean floor with a resolution of 5km (we can only see features as big as this). Gebco plans to provide a much more detailed map, giving us more information about every little crack and ridge, and maybe even lost planes?
The Benefits of Mapping the Seabed
An Organisation for Economic Co-operation and Development (OECD) report estimated that the ocean economy employed 31 million people full-time and generated $1.5 trillion each year. Maps – or the lack thereof – play a role in nearly every critical ocean issue, from sea level rise to ocean acidification to biodiversity. Pretty much anybody doing some kind of [ocean] research should probably be using or has used the Gebco data,” says Rochelle Wigley, the project’s director at the University of New Hampshire.
But it’s not just researchers that benefit; fibre optic cable companies have used Gebco to plan and lay the millions of miles of undersea internet cables. Since the first transatlantic cable was laid in 1858, the ocean has become home to a critical part of the infrastructure for our global communications network. Today, there are around 380 underwater cables in operation around the world, spanning a length of over 1.2 million kilometres. These cables form the backbone of the internet and are crucial to economic development across the globe.
Scientists though, have the most to gain from the project. One of the early discoveries has been the unearthing of a new reef of mid-ocean corals off Florida’s coast. Given how coral reefs in shallower waters across the world are under threat due to global warming, the discovery of a whole new ecosystem of deepwater corals is a fascinating find. In colder regions, Gebco data will be used in an upcoming study on ice sheets that aims to analyse how the rapidly melting ice is impacting on the ocean, its currents and sea-level rise. Considering the majority of humans live in coastal areas, such data will be crucial to understanding the potential impact of climate change. The First World Ocean Assessment, published by the UN Environment Programme in 2015, revealed that the ocean’s very ability to function was in jeopardy.
There are, however, plenty of other uses for the data. Six years after the fatal crash, there is still no news of the Malaysian Airlines MH370 plane that went down in the South Indian Ocean. With Gebco, it’s possible that the missing plane could finally be located.
But perhaps the most controversial use of Gebco is for deep-sea mining. A new frontier for resource extraction that is all set to go ahead despite reservations. With millions of dollars at stake, mining companies are reliant on Gebco to make the decisions about where the most profitable areas are to be found. And with resources on land drying up, the race is on to exploit the ocean floor’s resources.
Mining the Seas
The ocean floor is laced with the same diversity of minerals as found on land, and given how untapped they are to date, they represent a huge economic opportunity. Oceanographers have already discovered vast deposits of copper, nickel, silver, platinum, gold and even gemstones. Underwater mining programmes have already begun, but are yet to scratch the surface of the vast ocean floor.
In 2018, a fleet of ships owned by the De Beers Group extracted 1.4 million carats of diamonds from the coastal waters of Namibia. Japan and South Korea have also begun exploring their territorial waters for deposits. The real game-changer is, however, the mineral riches to be found in international waters. And for the mining consortiums, that’s where Gebco comes in handy.
Of course, all this comes at a cost. Jeffery Drazen, professor of Mechanical Engineering at MIT told Mongabay News: “it’s very clear now that mining is going to discharge huge volumes of muddy seawater into these mid waters, and we need to begin discussing what those effects will look like.”
Sediments from extraction are expected to flow all around the world, damaging the fragile marine ecosystems. Then there is the toll sonar takes on marine life. The noise generated by these machines can interfere with marine mammals like dolphins that use sound for hunting and communicating. There’s no real solution to these issues yet, as scientists are still struggling to understand the effects fully.
The data obtained by Gebco will form the foundation for the UN’s International Seabed Authority (ISA) to create regulations for ocean mining. The data will help the ISA to build a mining code for the ocean, as well as identify locations for extraction.
In the meantime, however, it seems very likely that the Gebco Seabed 2030 project will meet its goal. Once done, it could provide us with valuable information about our planet, both for commercial and scientific purposes. The only question is – can we ensure that we don’t damage marine life the way we damaged the surface?