The seas are warmer than at any point in human history and life under water is facing myriad threats, but there are still reasons to hope the Sustainable Development Goal focused on the world's oceans can be met
Oceans cover 70 per cent of the Earth's surface, but their size and remoteness can make them seem a world apart. "Man marks the earth with ruin; his control / Stops with the shore," as Lord Byron observed in 1810.
Today, however, we know the reverse to be true. In the course of the last century, the oceans have been transformed by human activity. Intensive fishing has decimated marine life, stripping the seas of scores of species. Plastic has infiltrated the remotest points on the planet, from the bottom of the Marina Trench to the Siberian Arctic. And humanity's 200-year habit of pumping carbon dioxide into the atmosphere is raising the temperature of seawater while lowering its PH level, unleashing a series of potentially catastrophic cascading impacts, from the melting of the polar ice caps and the rise of global sea levels to the collapse of the planet's coral reefs and the acidification of its oceans.
Responding to this environmental crisis, in 2015 the UN devoted one of its 17 Sustainable Development Goals (SDGs) exclusively to the state of the oceans. Goal 14 - dubbed "Life Under Water" - establishes a wide-ranging goal to "conserve and sustainably use the world's oceans, seas and marine resources". Breaking down this broad ambition are 10 targets, addressing key threats to ocean ecosystems, such as pollution, overfishing, acidification, while also setting specific goals for extending protected areas and supporting sustainable fisheries in the developing world.
Carbon crisis
The severity of the threat facing life under water is vividly demonstrated by the plight of perhaps the single most important marine ecosystem: coral reefs. The product of a symbiotic relationship between a coral polyp and an alga that lives in its skin, these spectacular structures shelter more than a quarter of all marine life.
"They're oases in the desert of the ocean, home to an explosion of different species", says Gabriel Grimsditch, a coral reefs expert with the UN Environment Programme (UNEP). The most extensive, the Great Barrier Reef off eastern Australia, covers more than 2,000 kilometres of seabed and in places is 150 metres thick.
Reefs are vital for human communities and the global economy too, providing food security for hundreds of millions of people and coastal protection for hundreds of millions more. "Coral reefs stabilise beaches and form a natural barrier to protect from flooding and erosion," Grimsditch says. In economic terms, the UN estimates these habitats are worth $365bn a year thanks to their contribution to tourism, fisheries, and coastal protection, but as any conservationist would tell you in reality these unique ecosystems are priceless.
Coral reefs are home to more than a quarter of all marine life |Credit: Grafner
And yet these 'rainforests of the ocean' are in mortal peril. In 1998, 16 per cent of the world's coral died in the space of a few months. The collapse was particularly severe in in the Indian Ocean. But it also stretched across the globe, reaching from the Caribbean to the South Pacific. The catastrophic event stunned the world's marine scientists. It was followed by two more breakdowns, one in 2010, and another that stretched from 2014 to 2017.
Coral reef collapse is directly linked to rising sea temperatures, leading Grimsditch to describe coral as "the canary in the coalmine for climate change". Corals live close to their upper thermal limit and even modest temperature rises can disrupt their relationship with their algae lodger. This causes the often-kaleidoscopic coral to turn white as it dies, a process known as bleaching.
One of the most eye-catching and sobering predictions from the landmark 2018 IPCC report on the respective impacts of 1.5C and 2C detailed how even under 1.5C of warming - the most ambitious goal in the Paris Agreement and one that many analysts think is already close to being out of reach - the world would likely see "the further loss of 90 per cent of reef-building corals compared to today". At 2C of warming coral reefs would "mostly disappear".
Only this week fresh research suggested the world's oceans are warming even faster than feared, with the past five years the warmest on record. "We found that 2019 was not only the warmest year on record, it displayed the largest single-year increase of the entire decade, a sobering reminder that human-caused heating of our planet continues unabated," Professor Michael Mann at Penn State University told The Guardian.
But rising temperatures are not the only threat to these vital habitats. Since the onset of the industrial revolution, humanity has thrown hundreds of billions of tonnes of carbon dioxide into the atmosphere. Roughly a third of these emissions have been absorbed by the oceans. When carbon dioxide dissolves in water, it forms an acid. The UN estimates that ocean acidity has increased by 26 per cent since pre-industrial times. At the current rate, an increase of 100 to 150 per cent is forecast by the end of the century. Such a shift would have a widespread, and only partially understood, impact on life under water, affecting thousands of species with calcium carbonate shells and sending shockwaves up the food chain. Coral reefs, ridges of calcium carbonate that have built up over millennia, are expected to be among the worst impacted habitats.
The pincer movement from rising temperatures and acidifying oceans means "corals are probably the most sensitive ecosystems in the world to climate change, and potentially the first one we might lose at a global scale", Grimsditch says. The IPCC predicts that with a 1.5C temperature rise, the world will lose between 70 and 90 per cent of the world's coral. A 2C rise would eliminate 99 per cent - including nearly all the Great Barrier Reef.
Rising ocean temperatures are causing bleaching events in the world's corals | Credit: Fish Tales
As these stark projections suggest, saving coral reefs will require action on a scale that goes far beyond the oceans. "When people talk about ocean health they tend to connect it with ocean activities, which is not necessarily right," says Erik Giercksky, head of the oceans programme at the UN Global Compact, which advises businesses on how they can align their activities with the Sustainable Development Goals. "The first step has to be in the direction of tackling climate change - and 96 per cent of all climate emissions are land-based."
But that is not to say that businesses with activities focused on and around the seas do not have a key role to play. Following the 1998 bleaching event, some coral reefs regenerated. But this resilience was seen only in coral living in healthy marine ecosystems, in protected areas or along shores with little population pressure.
As such, big hotels and other coastal facilities can help maintain healthy marine ecosystems, by properly treating sewage and avoiding certain chemicals in their daily operations. They can also consider investing in marine protected areas, Grimsditch suggests, and working with local communities to manage them.
Dive centres can also make a big difference, concentrated as they are around the world's remaining coral reefs. A UNEP programme named Green Fins works with more than 600 sites to improve their practices, for example.
"The reef is absolutely vital for us, we wouldn't be here if it wasn't for the coral," says Rosie Cotton, who runs Tioman Dive Centre in Malaysia. To minimise the centre's impact, she has switched from a two-stroke to a four-stroke boat engine, and started to use biodegradable washing liquids and suncream.
Sustainable shipping
Beyond tourism, efforts to clean up the shipping industry also have a critical role to play. The International Maritime Organisation (IMO) has set a goal to halve the industry's greenhouse gas emissions by 2050. With deep sea shipping currently far beyond the scope of full electrification, achieving the target will require technological advances on several fronts.
"One approach is Liquid Natural Gas (LNG), which is not emission free but can save up to 30 per cent of CO2 emissions while eliminating others," says Sverre Steen, head of the department of marine technology at the Norwegian University of Technology and Science. But LNG alone will not be sufficient to meet the target. "Energy-saving will be also very important, including using wind energy," Steen adds. One firm working to bring sails back to shipping is Norsepower, whose Rotor Sails were installed on a Maersk tanker in 2018, slashing fuel consumption by 9.2 per cent over the following year.
NorsePower Rotor Sails being installed on a ship | Credit: Norsepower
However, the shipping industry's efforts to curb its emissions and fall into line with the Paris Agreement's global push to build a net zero emission economy are currently at something of a cross roads. Last month the International Chamber of Shipping (ICS) unveiled sweeping proposals to raise up to $5bn for green shipping technology R&D through a $2 a tonne levy on marine fuels. The plan joins proposals from some shipping operators and NGOs for new fuel efficiency standards, carbon market mechanisms, and speed limits for the sector, all of which are designed to curb emissions.
But while the ICS represents seven international shipowner associations, collectively covering all sectors and trades, and over 80 per cent of the world merchant fleet, its vision for a more sustainable shipping industry does not yet enjoy universal backing. The International Maritime Organisation (IMO), the UN-backed body responsible for the global maritime sector, has committed to halving shipping emissions by mid-century and supporting the SDGs. It is working on a package of measures designed to curb emissions and chart a more sustainable course for the sector. But at the same time the agency has faced fierce criticism from environmental groups, which have accused it of making negligible progress and failing to deliver sufficiently ambitious plans.
With the agency requiring consensus from governments to introduce international emissions rules, the IMO's long running climate negotiations have fallen foul of many of the same tensions that have marred the wider UN climate talks. A handful of large emitters and countries with disproportionately large shipping industries stand accused of blocking more ambitious policies, while arguing that efforts to curb emissions could drive up the cost of shipping. Many leading shipping companies have pledged to accelerate their own efforts to decarbonise, but experts fear that without a global regulatory framework those green trailblazers risk being undercut by polluting competitors. The long term delivery of SDG14 is likely to rest on whether or not the deadlock at the IMO can finally be broken and a new policy regime developed that enables the development of a net zero emission industry.
No more fish in the sea
While climate change and acidification are transforming the world's oceans, their inhabitants face a much more immediate threat: the human diet. "We've seen a 70 per cent decline in the abundance of ocean life, in biomass in the sea, over the course of the last century," says Callum Roberts, a professor of marine conservation at York University.
Roberts grew up in the coastal town of Wick in the far north of Scotland, where every day he watched fish being landed by the local fleet. "The most vulnerable animals have declined by 99 per cent," he adds. One such creature is the common skate, a large flat fish nicknamed ‘the manta ray of the north'. "In the mid-19th century, fishmarkets looked like they were paved with skate," Roberts says. "Now they've been almost completely eliminated." In his 2013 book Ocean of Life, he calculates that fishers today - "in boats bristling with the latest fish-finding electronics" - land just six per cent of what they did 120 years ago.
Across the board, the primary driver of this decline has been commercial fishing. But the response from governments and industry has often served to exacerbate the problem. "When stocks declined in South East Asia and across the Pacific, there were only two ways to maintain profits," Roberts explains. "One was government subsidies - and there are plenty of pernicious subsidies that promote overfishing. The other was cutting back labour costs, and the way that fishing companies solved that problem was having bonded and slave labour on their boats."
SDG14 set stringent targets to combat overfishing. "By 2020, prohibit certain forms of fisheries subsidies which contribute to overcapacity and overfishing," orders SDG 14.6. But this target was missed. Diplomats made a last-ditch attempt to meet it at WTO negotiations in December, but the talks faltered and the issue was kicked down the road to the next round of negotiations, in June 2020.
Similar problems plague attempts to improve fishing industry regulations more broadly. While the US has made overfishing illegal and the EU maintains its controversial quota regime in a bid to ensure sustainable sticks are maintained, in much of the developing world there are almost no restrictions at all. And beyond those waters subject to legal restrictions there are the high seas - anywhere more than 200 miles offshore, governed collectively under the UN convention on the law of the sea - which are "very ineffectively managed" by transnational bodies, Roberts says.
This regulatory chaos can pose significant legal and reputational risks to seafood traders. "There's great interest from consumer-led companies not to buy illegally fished fish, and a big interest in bank and insurance companies not to be part of illegal or overfishing," says Erik Giercksky. But in such an irregular landscape, companies can find it hard both to put their good intentions into practice and to communicate the reality of complex supply chains to their customers.
The UN Global Compact is developing a tool to help companies navigate this landscape of reporting initiatives, so they can more easily disclose good practice. But Giercksky emphasises that more comprehensive solutions will be needed in the longer term.
"One umbrella solution is to have traceability, monitoring fish all the way to market," he says. "There are pilot projects towards this end, including installing cameras on fishing vessels so it's clear who's working there, and tagging fish with a small code specifying their origin. But they still face significant technical challenges. Hackathons together with UN technology and innovation laboratories are working to make fully traceable seafood a reality."
In many parts of the world, fisherman face no restrictions on how much catch they can land | Credit: Gorodenkoff
As well as seeking to rein in overfishing, SDG14 aims to help developing countries access their fair share of marine resources. In this sense, the goal reaches out to connect with other SDGs, including SDG1 on poverty, SDG8 on decent work, and SDG10 on inequality. Equally, with oceans providing the world's largest source of protein - three billion people depend on the seas as their primary protein source - it's clear that progress on SDG14 is absolutely fundamental to SDG2: ending world hunger.
"If you look at the global catch, up to 50 per cent is supplied by small-scale fisheries, but these fisheries employ 90 per cent of the people working in the industry," says Essam Y Mohammed, head of blue economy at the International Institute for Environment and Development (IIED). However, as fish is such a perishable product, commercialising your catch can be a challenge. "Enhancing market access is critical," Mohammed argues, explaining that 90 per cent of small-scale fishers are located in the developing world.
One major constraint for small-scale fishers is financial exclusion: an inability to access the financial services, whether insurance, loans or social protection schemes, needed to realise income and profit from their activities.
"Both state and business need to play a part in rectifying this," Mohammed says. "If the government can't provide financial loans or services, they can prioritise creating an enabling environment, incentives or guarantees, to make sure financial institutions can cater to these communities."
Plastic peril
Despite the dramatic challenges outlined above, it is neither the collapse of the ocean's richest ecosystems, nor the decline of its marine life, that has propelled the plight of the oceans into public consciousness. Rather, it is a third issue.
"You can pin down the recent surge of attention to almost a single event," says Giercksky. In early 2017, a six-metre Cuvier whale was spotted thrashing in shallow waters off the coast of Norway. After attempts to chase it out into deeper waters failed, it was shot. An autopsy revealed the reason for its distress: its stomach was clogged with plastic bags. The fate of the whale came to symbolise that of the many other marine creatures - including a million seabirds - that are killed by plastic every year.
If you make something with plastic, you've got to have a lifecycle plan for it - Marcus Eriksen, marine scientist
Plastics are just one of numerous pollutants endangering life in the oceans. Nutrients from agriculture cause "algae blooms" on the surface of the sea, which can smother reefs and other marine life. Sediment deposited by coastal construction work or deforestation has a similar effect. But while progress has been made on these issues, the tidal wave of plastics just keeps building.
"When we started, sewage was pumped continuously into the UK's seas," recalls Hugo Tagholm, director of Surfers Against Sewage. "Now, thanks to great campaigning combined with European legislation and big investment, it's improved dramatically."
The opposite, however, is true for plastics. "We've definitely seen a deterioration in plastic pollution," Tagholm says. "It's a massive crisis and clearly the biggest challenge facing planet ocean."
In 2013, a team from research institute 5 Gyres circumnavigated the globe to estimate the amount of plastic in the oceans. It placed the total at 270,000 metric tonnes - or 5.25 trillion particles clouding every sea on earth, from pole to pole.
Removing this plastic has proven near-impossible. High-profile projects such as the Ocean CleanUp have struggled to make any headway on the open seas. Instead, the CleanUp has turned its attention downstream, aiming to collect plastic from rivers before it reaches the ocean.
But Marcus Eriksen, the marine scientist who led the 5 Gyres expedition, argues that the problem can only be tackled at its source. "Remediation is a fools' errand," he avers. "What's needed is extended producer responsibility: if you make something with plastic, you've got to have a lifecycle plan for it."
As public awareness has grown - driven in large part by David Attenborough's landmark Blue Planet series as well as the periodic horror stories and viral videos documenting the plastic-related suffering of marine wildlife - manufacturers have increasingly engaged with the issue. In the UK, initiatives such as the Plastics Pact have seen a raft of high-profile firms such as Coca-Cola, Nestlé, Unilever, and PepsiCo pledge to ensure that 100 per cent of their plastic packaging is reusable, recyclable or compostable by 2025. Similar pledges have been made by many of the world's biggest retailers. Governments have also waded into the debate, with proposals for new plastic levies, recycling infrastructure, and extended producer responsibility schemes.
Eriksen, however, argues that manufacturers need to be much more ambitious if such commitments are to make any difference. "Recycling pledges are meaningless unless companies are actively investing in getting products back and recycled," he says. He suggests that manufacturers should step up the threshold of recycled content in their products, ideally aiming for 75 or 100 per cent. This ensures they have skin in the game, incentivising them to be actively involved in the recovery of plastics and the development of a recycled plastics industry. Some firms are taking a lead on this: Unilever brand Dove recently pledged to switch to 100 per cent recycled plastic for all its bottles, for example.
Another approach is the development of truly biodegradable biomaterials as a replacement for plastic in packaging, such as polyhydroxyalkie (PHA), a naturally occurring plastic made by the bacterial formation of sugar. "There are three companies working on this in the US and they can't make it fast enough," Eriksen says, adding that PepsiCo recently invested $25m in R&D for the material.
A third option is to reuse rather than discard plastic packaging. Tesco is bringing one such initiative, Loop, to the UK in 2020, while a host of big brands around the world are experimenting with closed loop packaging models.
TerraCycle's Loop service delivers sees brand-name goods to doors in reusable packaging | Credit: Loop
The hard truth, however, is that manufacturers remain a long way from turning back the plastics tide. Demand has more than doubled since 2000 and that upward trajectory is accelerating - fast. The richest nations use 20 times more plastic per person than developing economies, and as the global middle-class grows, it is widely expected that demand for plastics will continue to expand. In a recent report on the US petrochemicals industry, the Center for International Environmental Law (CIEL) identified "total investments of over $200bn in more than 330 new or expanded facilities" over the next decade.
Indeed, as energy and transport firms pivot away from fossil fuels, the petrochemicals industry is set to become the world's biggest driver of global oil demand. "If plastic production and use grow as currently planned," the CIEL study finds, "by 2030, these emissions could reach 1.34 gigatons per year - equivalent to the emissions released by more than 295 new 500-megawatt coal-fired power plants." It is a scary prospect: left unchecked, the plastics waste crisis could metastasize and undermine whatever progress is made in other areas of SDG14.
From warming and acidification to plastics and over-fishing, life under water remains among the most challenging of the 17 Sustainable Development Goals. For centuries, the planet's dominant land mammal has treated the oceans as a limitless larder with an inexhaustible capacity to absorb its waste. That illusion has been comprehensively shattered, but still the deeply embedded cultural and economic assumption that the open seas are an endless and alien world removed remains remarkably entrenched.
But oceans are not only threatened by human activity. They could also hold the keys to solving many of humanity's most pressing environmental problems. Renewable technologies such as tidal, wave and offshore wind seek to harness the immense power of the oceans to generate clean energy, creating giant marine reserves and artificial reefs in the process. And while tidal and wave technologies remain bogged down with some major if potentially surmountable cost and engineering challenges, offshore wind is developing at a galloping pace, as costs plummet and turbines scale up. A recent International Energy Agency report found the sector has the potential to generate 18 times today's global electricity demand. The vision of economies harnessing reliable offshore winds to power their cities and produce clean hydrogen for use in everything from aircraft to heating is no longer the stuff of environmentally friendly science fiction.
And as well as forming a vast reservoir of clean energy, oceans can also act as sustainable sources of food and deep carbon sinks. Over-fishing remains an immense challenges - a tragedy of the commons in its purest forms - but there are encouraging case studies detailing how where fisheries are well managed and no fish zones are enforced then habitats and fish stocks can recover. At the same time coastal habitats such as mangrove forests and seagrass beds absorb carbon dioxide through photosynthesis; out on the open ocean, plankton does the same. The potential for the ocean to play a critical role in the development of the nature based solutions that will inevitable contribute to the net zero transition is under-appreciated but obvious when you think about it.
But again, the capacity of the ocean to both recover as a habitat and absorb carbon dioxide is "fundamentally determined by the healthiness and vigour of the ecosystems themselves," as Callum Roberts puts it. We've finally learned that life under water and life on land are inextricably intertwined. Now we have to act on that knowledge.
