Time capsule

The ocean is full of mysteries and remains one the very few unexplored places on earth. It’s everywhere on the planet, yet widely inaccessible and, for the most part, invisible to us. Ocean pioneer explorer Sylvia Earle rightly said we know the surface of Mars better than our ocean floors.

In this quest for discovery, the team of scientific deep divers from Under the Pole decided to live on the reef and test out a light underwater habitat of their own design, allowing them to dive with no time limit and get intimate with the environment, observing the ocean like never before.

After their 2010 Deepsea Under the Pole by Rolex expedition, during which they dived for the first time under the geographical North Pole, French explorers Ghislain Bardout and Emmanuelle Périé-Bardout undertook their second expedition. Under the Pole II – Discovery Greenland, explored the depths of Greenland’s west coast for 18 months, including a winter caught in the sea ice on board their 60-foot schooner WHY.

Between 2017 and 2020, they embarked on Under the Pole III – The Twilight Zone. The objective was to study the mesophotic area – or twilight zone, between 50 and 172 metres – under all latitudes, from the Arctic to the Antarctic, with two groundbreaking missions in French Polynesia, including the Capsule program.

The initial idea for the Capsule was born in Ghislain Bardout’s engineering mind. The goal was to address a major challenge – time. While conventional diving with regular scuba tanks offers a simple way to explore the shallows, it’s highly inefficient for exploring deeper.

However, greater depths are already accessible for a very small number of highly trained divers who can use closed-circuit rebreathers, which give increased autonomy while reducing the time for decompression – the process of elimination of inert gases dissolved in the diver’s body. Decompression forces the divers to slowly ascend toward the surface and stop at a given depths, often for minutes, sometimes hours, depending on the dive profile. A failure to do so could result in a bend, a painful symptom requiring immediate medical attention that could be lethal in some cases. The longer and deeper the dives, the longer the decompression.

So, why the Capsule if the tech to go deeper already exists? The fact is that time still remains the main challenge in the process of exploration, scientific work and discoveries. A dive – even with a rebreather – remains a short incursion, often 45 minutes up to a few hours at best. But, observations take time.

Imagine poking your head in a forest for just an hour, hoping to study its biodiversity or witness animal behaviour. You probably won’t see much. Stay for a day, and you’ll witness a lot more.

In a week, you should get a good understanding of what’s happening in this ecosystem.

Without something like the Capsule, such timescales would be impossible – we need to hydrate, rest, eat and sleep, all of which is hard to do while diving. But also, the time spent doing decompression will far outweigh the time actually dedicated to the work and observations at depth. It would be like driving your car for three hours to get to work for an hour in the office, then drive three hours back. It’s a pretty inefficient use of time.

After a few hours, the body reaches a state of saturation as no more inert gases can diffuse in the body. When a diver reaches saturation, one more minute, one more day or one more week underwater will result in exactly the same decompression time needed for the final ascent, in this case four and a half hours. The Capsule is a way to maximise the usable time for exploration by allowing divers to spend a few days underwater, and give the divers time through saturation.

The Capsule was therefore designed as an underwater observatory and a shelter for three divers at a time. The time available for observations would be stretched over the entire day and night, whether in the water diving or inside the Capsule resting.

Although the idea of a capsule isn’t new – saturation diving programs have been dedicated to mining, oil, gas or the building of infrastructure – it has never been used to better understand our oceans, let alone their conservation.

This Capsule was designed as an observatory with two large domes on either side, a leave-no-trace philosophy in mind with no anchoring to the bottom, only two ballasts, and no connection to the land, only a surface antenna for comms.

The outer reef of Moorea near the island of Tahiti was chosen to install the Capsule – it’s an ideal profile with a vibrant reef in proximity to the research centre (CRIOBE) and the hyperbaric chamber of Tahiti. After scouting the area, a perfect site was found at a depth of 25 metres. First, the ballasts were installed precisely, one by one, on a tight space of sandy bottom so as not to damage the reef. Then the Capsule, anchored to the ballasts, was filled with gas and finally fitted with all the necessary electronics. After successful comms tests, it was ready to go.

Life underwater has a routine to it, but it’s not a dull one. After a long exploratory dive in the morning, usually deploying scientific protocols, it’s time for the aquanauts to come back to the Capsule for a rest. They remove their gear and clip it outside the Capsule before making their way up like astronauts to the moon-pool, the entry-exit hole in the Capsule’s base.

Inside the Capsule, divers breath a mix of helium and oxygen, granting everyone a high-pitch voice, which makes for some good laughs. Life underwater is a challenge to the senses – with helium, not only the voice but the sense of smell is sharply altered.

In addition, the lack of a red wavelength in the sunlight, which gets absorbed in the first 10 metres of water, gives a weird look to the food – the tomato sauce in the pasta becomes a vivid green, for example. All hues are blue, contrasts are muted, and all sounds are muffled. The return to the surface in a few days feels like a sensory overload, with blinding reds, blues, greens, whites, intense odours and a dry touch.

The comfort inside the Capsule is extremely basic – for the night, there are three bunks and a thin camping mattress to sleep on.

During the day, one bunk acts as a bench to sit on, while the other is folded down for a backrest. Across, the third becomes a table.

Once inside, it’s time to get dry and have lunch. The meals and the dry towels are brought down daily by the support divers who prepare all the necessary equipment, food and water into pressure-resistant containers. After lunch, the divers gear up again to go out for another scientific dive, before coming back a few hours later to spend the night in the belly of the Pacific Ocean. The diving equipment is left outside the Capsule and will be picked up by the support divers in the evening. In the morning, the next shift will bring three fresh rebreathers with full tanks.

Around the clock, the Capsule is monitored on shore by the rest of the team. All the atmospheric parameters are under close watch by those on the roster, as well as the live video feed from the Capsule, which is especially important at night when the divers are asleep and incapable of detecting issues or spotting an emergency.

Mission Control can easily trigger an alarm in the Capsule for the divers to escape quickly, in the event of a fire for instance. In addition, under their pillow, each diver has a small safety tank and a mask in case of an evacuation, giving them enough time to reach a bunch of tanks a few metres away from the Capsule.

Living in the Capsule changed the way the divers saw the reef.

Almost to the minute, the same fish were observed doing the same routine every day. The same fights would happen between the same neighbours in a given coral head, and the patrolling sharks would follow a similar trajectory every time.

What looked like a reef filled with randomness started to look like place of harmony and order. The repetitions of the typical interspecies’ social interactions and the genuine intraspecies behaviours could only be observed because of the long stretch of time spent underwater.

Living in the Capsule also came with a few realisations – even as experienced and keen professional scientific divers, we know close to nothing about our oceans and, for the main, have a distorted view of what is really happening when we’re not there.

It also proved that the concept worked in practice and reinforced the vision that such saturation diving programs dedicated to science are proving to be a highly efficient tool to make leaps in scientific discovery and therefore conservation.

Some current limitations could be overcome by the build of Under the Pole’s next expedition ship. Pending final funding, an exploration ship named WHY NOT would be specifically designed to accommodate two Capsules and the safety and support systems necessary to push the exploration to 200 metres in every ocean and season. Equipped with two fast boats, a marine biology laboratory and a decompression chamber, WHY NOT is the key to a deeper knowledge of the oceans – and making the invisible visible.

underthepole.org