Will Life Beneath the Waves Shape Our Future as Sea Levels Rise?

The Bajau are indigenous marine people of Southeast Asia, often referred to as sea nomads. For millennia, they have thrived along coastlines, relying on foraging underwater without the aid of diving gear, holding their breath for astonishing durations. Yet, the early 21st century introduced multiple crises that jeopardized their way of life—industrial overfishing, pollution, coral bleaching diminished food sources, and rising sea levels consumed coastal dwellings.

In 2035, a Bajau community near Saba, North Borneo, initiated fundraising for a contemporary floating and underwater settlement. They collaborated with deep, a manufacturer of submarine habitats, to create interconnected rafts and underwater homes, developing business models that could be emulated by other maritime communities facing similar threats from rising seas. Revenue streams included extreme adventure tourism, scientific research facilities, and longevity clinics.

The first habitat comprised a network of platforms and rafts, with tunnels leading to underwater levels. While residents occupied surface structures, they increasingly utilized submerged areas for storage, sustenance, and sleep. This habitat was constructed using a 3D printing technique known as Wire arc additive manufacturing, which allowed the most effective pressure distribution in areas experiencing strain.

The deeper sections were maintained at both ambient water pressure and the corresponding atmospheric pressure from the surface. In modules situated less than 20 meters deep, occupants, referred to as Aquanauts, inhaled a unique gas mixture to prevent nitrogen narcosis. Those exiting deep modules required decompression when returning to normal atmospheric conditions. An advantage of these surrounding modules was the incorporation of a moon door, enabling Aquanauts to swim directly into the deep sea for leisure, research, and farming activities.

Undersea hotels catering to extreme tourism have surged in popularity. In the Galapagos, tourists reside in submerged hydroelectric hotels, exploring hot springs and observing some of the planet’s rarest life forms. Simultaneously, scientists harness these modules to investigate deep-sea ecosystems. Undersea mapping technologies have evolved, enabling researchers to explore vast ocean territories that were previously unreachable, fostering understanding and interactions with whales and other deep-sea creatures, leading to significant advancements in marine biology.

The Bajau have long been adapted to marine environments. With thousands of years at sea, they possess enlarged spleens that provide a higher quantity of oxygen-retaining red blood cells compared to typical humans. Some Bajau divers can spend five hours underwater, diving freely to depths of 70 meters without oxygen tanks, holding their breath for up to 15 minutes. After transitioning to seabed habitats, many Bajau began to leave behind surface living, opting instead to spend more time submerged, even resorting to gene editing to enhance their aquatic capabilities, including intentional eardrum puncturing to facilitate deeper dives, and utilizing surfactants in their lungs to aid their decompression, akin to adaptations found in diving marine mammals.

Numerous communities have established depth clinical treatments. Previous research has demonstrated that exposure to intermittent daily sessions of pressurized oxygen therapy can alleviate various medical conditions and age-related diseases. Hyperbaric oxygen therapy, for instance, has proven beneficial, leading individuals who underwent consistent high-pressure sessions to possess longer telomeres and enhanced clearance of senescent cells, both of which are linked to increased longevity. The deep habitat has attracted affluent seniors looking to extend their lives, simultaneously providing a lucrative income source.

The majority of marine communities have become self-sufficient, cultivating their own food through aquaculture of fish, mollusks, and seaweed, while also growing other crops on the surface. Energy sources include a combination of solar, wind, wave, and geothermal energy, tailored to local conditions. Some communities focus on tourism, whereas others specialize in carbon capture within medical facilities. A significant amount of seaweed is harvested, sunk into the ocean depths, and sold as carbon credits.

Living beneath the waves isn’t for everyone. Nonetheless, these habitats empower those most vulnerable to climate change, giving them the tools to redefine their livelihoods and lifestyles, even in the face of rising sea levels that threaten their homes.

Rowan Hooper is the podcast editor for New Scientist and author of *How to Spend $1 Trillion: These are 10 Global Issues That Can Be Actually Fixed*. Follow him on Bluesky @rowhoop.bsky.social