The deep sea is only partially explored for less than 1% of its area, making it practically like another planet on Earth. Thousands of meters underwater, deep canyons, towering mountains and boundless plains harbor countless yet undiscovered species. Distant and unknown and yet closely connected to us, abyssal ecosystems are the basis of our very existence. Protecting their delicate balance and biodiversity assets from the impacts of activities such as mining will therefore be increasingly critical to the health and future of the planet.
We spoke with Diva Amon, a marine biologist who is among the leading experts on abyssal ecosystems. She is also an executive board member of the Deep-Ocean Stewardship Initiative and a member of the World Economic Forum’s Friends of Ocean Action community of scientists.

Diva Amon a bordo di un HOV (foto Solvin Zanki)

What do we currently know about the deep sea? What’s the state of research?

Humans have been researching the deep sea for over a century, and our knowledge has grown exponentially thanks to the emergence of new technologies. The exploration of the deep sea is still, however, in its infancy. For example, we have much better maps of the Moon, Mars, and Venus than we do of our own ocean floor, which has not been mapped in its entirety. However, maps are just one component of the exploration: far less than 1% of the deep sea – it would be more like 0.0001% – has actually been seen with human eyes or with cameras. For the most part, we have no idea what lives there. We are unaware of the ecology of those species, and we don’t know how they cope with human activities and their impacts, or how to mitigate those impacts. We still have a lot to learn, and I’m absolutely certain that the deep sea holds some incredible discoveries still to be made and potentially some solutions to some of humanity’s greatest challenges in the future.

For example?

Well, something that we are increasingly turning to the ocean for is marine genetic resources (MGR). We’re using those resources for medicine, pharmaceuticals, biomaterials and so on. For instance, we already produce a lot of medicine from shallow water species, but it’s highly likely that in the future we’re going to be getting even more from the deep sea.

What kind of exploratory techniques are used today?

We use a range of different technologies, including mapping systems, trawl nets, and much more sophisticated methods of sampling, like remotely operated vehicles or ROVs. These are essentially robots that we send down into the deep sea; they are connected to the ship and we’re able to control them, and they are our eyes, our ears and our hands on the deep sea floor. Additionally, we have things like autonomous underwater vehicles, which are similar to remotely operated vehicles, but are completely detached from the ship. So, you program them to go on a mission, whether that be looking for certain chemical signals or taking pictures of the deep sea floor. However, there is more that they can do. And then, of course, there’s our piece de resistance, the submersibles or human occupied vehicles – HOVs: they are basically our chariots down into the deep sea, though their use is still quite rare globally.

Have you ever used one of them?

I have used them, yes, on a number of occasions. And let me tell you, it just is an incredibly magical experience. You see those otherworldly seascapes, incredible species, incredible new behaviors, and often, many of them are new to science and no one has seen them before.

How deep did you go?

The deepest that I have been is only about 2600 meters. I say ‘only’ because the deepest point on the planet is 11 kilometers, so I’ve barely done a quarter of that.

You once said that we could potentially have a Grand Canyon or a Himalaya under the sea, and we just don’t know.

Exactly! Some of the tallest mountains on the planet are actually in the ocean, there are trenches that are kilometers deep. The landforms in the deep sea are incredibly similar to those on land, but in some ways, they are even larger than those we know.

What kind of ecosystem services depend on the deep sea?

The average person does not interact, or doesn’t think they do, with the deep sea on a daily basis, but our lives are intrinsically linked to it, and we benefit from it every single day. Many different ecosystem services are provided to keep the planet habitable and keep us and all life alive. As we mentioned, it provides marine genetic resources and non-living resources, such as oil and gas. It may also provide potential minerals in the future and renewable energy, such as wind or geothermal energy. And it also potentially supplies nature-inspired innovation, such as biomimicry. Beyond the tangible things, there are many things that are not tangible, like ways in which the deep sea helps to regulate the planet. The deep sea is a critical component of biogeochemical cycling, the cycling of elements, nutrients, and chemicals, and the regulation of our climate. It also helps to absorb heat and is critical for sequestering and storing carbon. We also know that it plays a really important role in providing fisheries that billions of people rely on around the world.
And finally, one thing that people often underestimate about the deep sea is that it also has cultural value. We use it for scientific research, we benefit from it in terms of education, it has entertainment value, historical value, emotional value, and spiritual significance to many communities around the world. So really, there is a lot that we get from the deep sea, not just the value it inherently has for its own biodiversity.

Regarding the exploitation, there’s been a lot of talk lately about deep sea mining. What risks would it entail for ecosystems?

To date, 31 licenses have been granted for exploration as a precursor to the exploitation of minerals in the deep sea. If the technology and methods proposed currently are used, it could cause significant damage to essential ocean ecosystems, some of which are closest to pristine on the planet. And it may do so across enormous scales that have never been seen before in the ocean.
Some of those impacts include the direct removal and destruction of the seafloor habitat, along with the unique fauna that lives there. Since much of this fauna is not able to move because it’s actually a patch, things like corals, sponges, and other species are in danger.
The mining process would create plumes of sediment resembling dust storms. There would be two types of plumes, one from the seabed mining process and one from the wastewater return, and those plumes could extend the footprint of mining potentially tens to hundreds of kilometers beyond the actual mine sites. We also know that there would be contaminants released from the mining process, as well as increases in noise and light that have never been seen in these very sensitive deep sea habitats. So mining is essentially going to cause biodiversity loss and ecosystem degradation, and that could impact many of the ecosystem services that we discussed earlier.

What is particularly concerning about all of this is not just the spatial scale – some industry projections for the area where there is the most interest are about 500,000 square kilometers of seafloor being mined – but also the timescales. In the deep sea, life is very slow and that means that it is highly vulnerable to disturbance and extremely slow to recover. So, in many of these habitats where deep sea mining may take place in the future, like in abyssal plains with nodules as the Clarion-Clipperton Zone, the recovery would take millions of years. The polymetallic nodules that are being sought after take millions of years to form, and more than 50% of the species living in this area actually use them to attach to. The nature of the damage entails irreparable destruction, which implies that if mistakes are made, the ecosystem will not be able to recover. There are certainly a lot of concerns about mining moving forward, especially on the very rushed timescales on which many would like it to happen.

But the International Seabed Authority – ISA will (probably) begin accepting applications for industrial-scale deep-sea mining in Pacific waters in July 2023. Many countries and scientists are now calling for a moratorium. Do you think it is still possible?

As you emphasized, this is a particularly significant year for deep sea mining. What we can say with certainty is that the ISA does not yet have the scientific knowledge needed to guide the regulation and management of deep sea mining. Furthermore, the exploitation regulations remain incomplete, and no financial mechanism has been established to share the benefits of mining. This is critical considering that the minerals in international waters are considered to be a common heritage of humanity and should benefit all of humanity, including future generations. In order to get these three critical elements in place and then be able to decide whether mining can happen while protecting the marine environment, the best option is a moratorium or a precautionary pause. And it is absolutely possible.
Sure, we’re in a race against time, but we’re seeing a growing movement: we currently have 13 countries that have come forward and called for a moratorium or a pause, and France has actually called for a full ban on deep sea mining. In addition to that, we have civil society, there are plenty of different companies, like Google, BMW, Volvo and Volkswagen, who are committing to not using minerals from the deep sea. And then there are more than 700 ocean experts who have also called for a pause. So really, there are many voices growing in size. The question is whether they will be able to grow quickly enough, given that this year’s clock keeps ticking.

This time bomb has basically been triggered by the government of Nauru, which wants to force the ISA to accept deep-sea mining applications, even if standards are not set, by appealing to the "two-year rule". But why is an island state pushing so hard to start mining the deep sea?

Well, Nauru has said that they would like mining to happen for several reasons. One is that they can gain the minerals that are currently needed for the energy transition, to combat the climate crisis. Obviously, there would be an economic gain from the sale of those minerals. However, I would push back on that by saying that the ocean is our greatest ally to fight the climate crisis, and deep sea mining is only going to lower its ability to help us with that. So essentially, mining the deep sea to solve climate change is like smoking to lower stress: ultimately, we’re going to be doing long-term damage for just a small short-term gain.

However, there is a company, Impossible Metals, which is working on sustainable technologies for collecting deep sea metals. Do you think “sustainable” deep sea mining is really possible?

Ultimately, it depends on what your definition of “sustainable” is. You know, no matter the scale or method by which deep sea mining is done, there will be biodiversity loss and there will be habitat loss. Impossible Metals is saying that they can selectively choose nodules, so they leave the ones that have life on them, and they only take a certain amount to ensure that a lot of the habitat remains. If that is the case, then that is certainly a much better method than many of the other companies are proposing. However, I have not yet seen the technology and as far as I’m aware, it is not yet proven. But, you know, Impossible Metals is just one of the companies thinking about doing deep seabed mining: there are more than 20 of them, and they are not thinking about using that technology. So, what is setting up to occur now is essentially a rapid and unrestrained expansion of very destructive mining in a near pristine deep sea ecosystem, and that to me does not support the sustainable use of natural resources in ecosystems. www.impossiblemetals.com

Besides mining, what other forms of exploitation are posing risks to the deep sea?

The deep sea has actually been used by humankind for decades, even centuries. It’s been used for legal and illegal dumping, oil and gas extraction, the harvesting of marine genetic resources, scientific research, and also, increasingly, tourism. We’re really seeing a push into the deep sea more and more, with plenty of new industries emerging. There are also proposals to address the climate crisis, such as carbon capture and storage or other forms of geoengineering, such as the sinking of Sargassum. But what we’re learning is that, as I said, the deep sea is very fragile and vulnerable to impact, and so we need to make sure, before we proceed with any of these forms of exploitation, that we understand what the risks are.

Do you think the High Seas Treaty will be an effective tool to protect the deep sea and regulate its exploitation?

I think the High Seas Treaty is an enormous win for humankind, thanks to the countless negotiators, scientists, and civil society representatives who spent decades working on it. But ultimately, how successful the High Seas Treaty and how effective a tool it is depends on how it is implemented. Currently, it is just ink on a piece of paper. I sincerely hope that the Treaty will be an opportunity that we take advantage of with both hands, not just to effectively steward the ocean, but to ensure that the benefits to humankind are shared equitably.

What is the Deep-Ocean Stewardship Initiative to which you are a part and what’s its mission?

I’m on the executive of the DOSI and very proud to be. It’s a global network of experts that integrate numerous different topics, from science to technology to policy, law and economics. We advise on the management of the deep sea and how we can maintain the integrity of its ecosystems globally. Our mission is to use independent scientific findings to support an ecosystem-based management and develop deep ocean strategies and solutions for the future. 

Do the policymakers listen to you?

That’s what we want, ideally! We do our best to bring Western science to many of these big ocean negotiations and climate negotiations in order to ensure that the deep sea is included in those conversations. Sometimes, we’re successful. We have worked a lot with the High Seas Treaty, with the climate COPs, with the ISA and various fisheries negotiations. But it is often very difficult because science, politics and communication operate in entirely different languages. So, our goal is to work collaboratively and patiently, building lasting relationships. Because ultimately, we need science, communication and politics – they are all keys to creating positive change for the ocean.

Image: Diva Amon (Novus Select_bioGraphic)

Download and read issue #45 of Renewable Matter on the ocean an the blue economy.