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UN to start ratifying historic deal to protect high seas

February 20, 2023

While the high seas make up over 60% of the world's oceans, they have long drawn less attention than coastal waters. A UN treaty aims to change that by attempting to ensure the sustainable use of the oceans.

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A school of yellow-backed fusilier fish glides past a healthy coral reef off the Maldives, as the sun shines through the water above
Who's protecting fish and other sea creatures in international waters?Image: Henley Spiers/AP/picture alliance

The United Nations is to open the ratification process for a "critical" landmark treaty to protect vast swaths of vital ocean ecosystems on September 20 at its General Assembly meeting in New York. 

The treaty was adopted in June, in a move that has been welcomed by environmental groups that believe it will help reverse the loss of marine biodiversity and promote sustainable development.  

"The High Seas Treaty is integral to being able to protect the ocean," Rebecca Hubbard, director of the High Seas Alliance, told DW when the treaty was adopted. The alliance is made up of more than 50 NGOs that want to strengthen ocean governance.  

"But it is also crucial to mitigate climate breakdown and to safeguard the lives and livelihoods of billions of people around the world," added Hubbard.  

The news comes as scientists announced the highest global sea surface temperatures for April and May since recording began in 1850. Oceans are the "world's greatest ally against climate change," as they generate 50% of global oxygen and capture 90% of excess heat generated by greenhouse gas emissions, according to the UN.  

At the meeting adopting the treaty, UN Secretary-General Antonio Guterres said oceans are the lifeblood of the planet and that the agreement will give them a fighting chance.

What does the historic oceans treaty leave unresolved?  

The legally binding treaty, agreed in March after five rounds of protracted UN-led talks with negotiators from over 100 countries, now must be signed and ratified by 60 countries before coming into force. But the adoption marks a significant turning point in the effort to protect the high seas and preserve marine life.

The treaty is expected to contribute to the conservation and sustainable use of marine resources, while also protecting the rights and interests of all countries involved. 

Fishing, shipping, tourism and ocean protection are currently controlled by around 20 organizations. However, their regulations only apply to a distance of 200 nautical miles (230 miles, 370 kilometers) from the coast. Farther out, international waters start, and individual states don't have any power or say. 

Although the high seas make up more than half of the surface of the Earth and 61% of all oceans, only 1% of international waters are under protection.

Illegal fishing, overfishing and other forms of damage to the ecosystem — such as deep-sea mining and oil and gas drilling — can hardly be consistently monitored, tracked or prosecuted.

Conservationists hope the treaty will help fulfill the international obligation to protect 30% of the world's oceans by 2030, as agreed in a landmark December 2022 deal.

Fish are seen in the net as they are landed following the second trawl of the day
It's virtually impossible to control what's happening to fish in international watersImage: Ben Stansall/AFP/Getty Images

"This is the minimum scientists have said we need to prevent ecosystem collapse in the oceans — our greatest shared resource and the foundation of life on this planet," Arlo Hemphill, Greenpeace USA's senior oceans campaigner, told the AFP news agency back in March. He added that it is "the biggest conservation agreement in the history of the world." 

The treaty creates a legal framework to allow for the creation of ocean sanctuaries. But many questions remain unanswered, including where and when the sanctuaries will be established and how remote areas away from the coast will be protected. Once it's been ratified by individual states "that work can begin," said Rebecca Hubbard, adding that ratification must happen as quickly as possible to "halt the biodiversity crisis that is occurring in the ocean." 

The goal is to have the treaty ratified by June 2025, when the UN Ocean Conference takes place in France, said Hubbard. 

"It is very fast for ratification, but it's absolutely achievable and it's absolutely necessary," said Hubbard. "We're calling on the High Ambition Coalition to drive that ratification process and to support countries around the world to do so." 

Why is a healthy underwater world so important for humans and our planet?

The resources of the ocean don't just sustain coastal dwellers but almost 3 billion people worldwide. The entire sea industry has a worth of $3 trillion (€2.8 trillion) — that's 5% of the world's gross domestic product.

The ocean isn't just important for beach tourists and fishers. We also need it in order to generate sustainable wave and tidal energy, as well as for the production of commodities and even medicine. 

Some agents used to fight leukemia, for instance, are derived from a shallow water sponge called Tectitethya crypta, which can be found in the waters of the Caribbean. The poison of the fish-eating sea snail Conus magus is being used to develop an effective painkiller. Many similar possibilities have yet to be explored, but scientists see a huge potential for the treatment of diseases.   

Why is climate change so stressful for oceans?

More than half of the total amount of oxygen in our atmosphere is created by creatures in the ocean. At the same time, oceans store 50 times more carbon dioxide than what's currently found in our atmosphere. The warmer the ocean gets, the less CO2 it can store. It's a vicious cycle: The warmer it gets, the less our oceans can protect the planet from even more extreme weather events.

If temperatures keep increasing at their current pace, scientists believe many shellfish such as mussels and snails will be unable to survive. That's due to ocean acidification: If the CO2 content in the seawater increases, the PH level in the water changes. The increasing acidity hampers the creation of the chalky shells of such animals. This throws entire biospheres off-balance and in turn could threaten economic sectors like oyster and mussel breeding.

Great Barrier Reef, seen from above
The most well-known example of coral bleaching is the Great Barrier Reef in Australia Image: Bildagentur-online/McPhoto-Schulz/picture alliance

Rising temperatures in the atmosphere — triggered by the burning of coal, oil and gas — also change ocean currents as water gets warmer. This can mean death for many creatures, such as corals. Corals live in symbiosis with colorful algae that help feed them. The warming of the water can lead to algae death, which means more stress for corals, leading many to lose their color, a phenomenon known as coral bleaching.

How can we protect ocean ecosystems?

If nothing changes, half of all sea dwellers will be critically endangered by the end of this century, according to estimates by UNESCO. This doesn't necessarily mean we can't use the ocean any longer. It just means we have to use it in a way that doesn't harm it, or at least only harms it to the extent that it can regenerate on its own.  

As an example, 10 million tons of fish have to be discarded every year because of bad fishing practices and processing. This waste could be prevented and in turn directly decrease pressure on our oceans.

Shanty houses with hanging toilets, with waste that runs straight into the river below, are seen in downtown Jakarta
Toilet waste that runs straight into the river is polluting our waterwaysImage: Bay Ismoyo/AFP/Getty Images

Another example is sewage. Around 80% of global wastewater is currently being diverted into oceans unfiltered. In the world's poorest countries that number is closer to 95%. This wastewater pollutes, contaminates and destroys oceans and coastal regions. Building sustainable sewage systems, especially in developing countries, would protect ocean ecosystems and contribute to better drinking water supplies in many places.       

Will a new treaty help save the oceans?

According to the UN's environment program, international treaties are one of the best ways to stop the destruction of oceans. 

Many treaties designed to protect coastal waters have been signed in recent years. Some have already had a positive effect on the environment; many, however, have failed meet their goals. That has to do with the fact that agreements are always dependent upon national parliaments — first in turning them into law, and secondly in allocating enough resources to the institutions and projects able to help achieve stated goals. 

Saving coral reefs with scissor art

This article was first published in German. It was updated on September 19, 2023 to reflect the UN beginning the ratification process, with additional reporting from Jennifer Collins.