Facing up to accelerating exploitation of oceans

Termed the “blue acceleration”, the rapid increase in human activity and resource extraction from the world’s oceans in recent decades highlights the growing pressure we’re placing on marine ecosystems.
Irish science journalist Olive Heffernan has tackled the topic in her first book, The High Seas — Ambition, Greed, and Power on the Unclaimed Ocean, and looked at how the rapid pace of development in the ocean raises immense concerns about the long-term health of marine ecosystems.
The increased intensity and diversity of ocean use we are now experiencing include activities such as overfishing, shipping, the associated pollution from diesel and oil spills, and deep sea mining within a marine ecosystem which is already under pressure from the adverse effects of climate change.
Heffernan looks at how the “blue acceleration” is driven by a growing global population and increasing demand for food, materials and space. As land-based resources become more limited, the ocean is now seen as a new frontier for exploitation. In the first of a two-part series, Conor Purcell interviewed her via video link:
I wanted to write the book to inform people about what I feel is at stake right now, and in the future, across a resource-limited and climate-impacted global ocean. I wanted to explore why it’s so important that we think about this carefully, and why it’s so important that we use our oceans sustainably.
But I also wanted to write something that would pay homage to the deep sea and that would inform people about the magnificent habitats and species that are out there, which most people are unaware exist. So the book is partially to impart some of my passion for the ocean to the public, and also to communicate that there are a lot of important decisions being made right now about how we use this space.
Half of the ocean is beyond national borders. Most coastal states have territorial seas that go out to about 200 nautical miles, but everything beyond that is this vast, unclaimed, territory. It’s like our largest global commons. If you think about it in terms of the habitat on Earth, it’s actually 95 per cent of what’s available. It’s enormous.
I feel that we are at a crucial juncture in time in terms of our relationship with this unclaimed territory. What I mean is that people are now looking to create new exploitative agendas for how we might use the space. Corporations are realising that resources out there are incredibly valuable.
Lost City is a place of unbelievable natural beauty covering an area of around 500sq m in the mid-Atlantic Ocean. When scientists first stumbled upon it, they basically thought that they had come across some sort of an abandoned metropolis with these incredible organic towers which are built from minerals seeping out of the seabed in so-called hydrothermal vents.
What’s amazing about Lost City is that scientists now think that it holds the clues to the origin of life on Earth, because it has this unusual presence of life forms surviving in an environment that’s extremely sulphuric and in above-average water temperatures. Since it is now recognised as a unique environment it is currently earmarked for World Heritage status.
Unfortunately, the area is not really protected. Recently, Poland has been given the right to mine in the region and so Lost City faces potential devastation.
The twilight zone is that area of the ocean between the layers at 100m and 1,000m. Up until recently, we’ve known very little about it. Going back 200 years, some scientists believed that below about 200m there was no life. But we now know that the ecosystem there is incredibly diverse and many say that it is the largest untapped fishery resource on Earth.
Now, these are tiny fish — they’re about a quarter of a centimetre in size — so they’re not something that we’re going to eat directly. But the idea is that we could use these fish to feed salmon and other farmed species.
But there’s a problem. The problem is that scientists are simultaneously figuring out that the presence of these fish in the twilight zone is one of the most effective ways that carbon is taken out of the atmosphere and stored in the ocean — acting as a buffer against climate change.
So the biology in the twilight zone is responsible for absorbing much of the carbon emissions that we’ve released into the atmosphere since the beginning of the industrial revolution. Without this, the temperature of the planet would be a lot higher. So it’s a really important area and we have to recognise that exploiting the resources there is a risky idea.
At some point in the near future, the Arctic will be totally ice-free in the summer. China has plans to create a new shipping route through the central Arctic, which would save shipping times taken through the Suez and other existing sea routes that connect the Pacific. They see it as something of a polar silk road. This will be a high seas shipping route, which means they won’t have to pay the tax or passage rates for going through Suez.
China is becoming extremely interested in Arctic science and tech, and they’ve been sending their own research vessels to look at the rate of climate change there. They’ve also branded themselves as a “near-Arctic” State, which is a contentious issue considering that Shanghai is thousands of kilometres away.
The problem with increased shipping in the Arctic – and China would presumably increase activities hugely – is that shipping always increases pollution locally. This usually manifests as oil spills in the sea, and diesel into the atmosphere, which further contributes to rising emissions globally, which in turn hastens warming and further ice melt in the region.
Last year a new UN High Seas Treaty, also known as the agreement on Biodiversity Beyond National Jurisdiction, was signed. That means that we now for the first time in history have a law stating that huge parts of the high seas are to be set aside in line with protected areas.
It took almost 20 years of negotiations and is hugely significant because it’s the first time an agreement was signed providing for the common governance of about half of the Earth’s surface and 95 per cent of the ocean.
The treaty offers the possibility of a real sustainable balance between how we use and how we protect the oceans and will allow the establishment of marine protected areas in the high seas. So there is hope, but we have to work hard, and fast, to protect the future.
Dr Conor Purcell writes about science, society and culture and can be found on X @ConorPPurcell — some of his other articles are at cppurcell.tumblr.com