
‘Ticking timebomb': Sea acidity at critical levels and threatens entire ecosystems
The world's oceans are in worse health than realised, scientists have said, as they warn that a key measurement shows we are 'running out of time' to protect marine ecosystems.
Ocean acidification, often called the 'evil twin' of the climate crisis, is caused when carbon dioxide is rapidly absorbed by the ocean, where it reacts with water molecules leading to a fall in the pH level of the seawater. It damages coral reefs and other ocean habitats and, in extreme cases, can dissolve the shells of marine creatures.
Until now, ocean acidification had not been deemed to have crossed its 'planetary boundary'. The planetary boundaries are the natural limits of key global systems – such as climate, water and wildlife diversity – beyond which their ability to maintain a healthy planet is in danger of failing. Six of the nine had been crossed already, scientists said last year.
However, a new study by the UK's Plymouth Marine Laboratory (PML), the Washington-based National Oceanic and Atmospheric Administration and Oregon State University's Co-operative Institute for Marine Resources Studies found that ocean acidification's 'boundary' was also reached about five years ago.
'Ocean acidification isn't just an environmental crisis – it's a ticking timebomb for marine ecosystems and coastal economies,' said PML's Professor Steve Widdicombe, who is also co-chair of the Global Ocean Acidification Observing Network.
The study drew on new and historical physical and chemical measurements from ice cores, combined with advanced computer models and studies of marine life, which gave the scientists an overall assessment of the past 150 years.
It found that by 2020 the average ocean condition worldwide was already very close to – and in some regions beyond – the planetary boundary for ocean acidification. This is defined as when the concentration of calcium carbonate in seawater is more than 20% below pre-industrial levels.
The deeper in the ocean they looked, the worse the findings were, the scientists said. At 200 metres below the surface, 60% of global waters had breached the 'safe' limit for acidification.
'Most ocean life doesn't just live at the surface,' said PML's Professor Helen Findlay. 'The waters below are home to many more different types of plants and animals. Since these deeper waters are changing so much, the impacts of ocean acidification could be far worse than we thought.'
As pH levels drop, calcifying species such as corals, oysters, mussels and tiny molluscs known as sea butterflies struggle to maintain their protective structures, leading to weaker shells, slower growth, reduced reproduction and decreased survival rates.
The authors said decreasing CO2 emissions was the only way to deal with acidification globally, but that conservation measures could and should focus on the regions and species that were most vulnerable.
The Guardian
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


Irish Daily Mirror
9 hours ago
- Irish Daily Mirror
Europe's first 'boil in the bag' funerals happened in Meath - and are set for UK
'Boil in a bag' funerals could soon be made available across the UK, offering an environmentally friendly, yet controversial, way to say your final goodbyes to a loved one. This unusual method, officially known as water cremation or alkaline hydrolysis, is currently effectively banned in the UK, but could well get the legal go-ahead following the independent Law Commission's new consultation into funerary methods. And Ireland has paved the way. Already available across 30 US states, as well as Canada and South Africa, the first European water cremation facility, or resomation, opened its doors in early 2023 in Navan, Co Meath, Ireland. Traditional burials can lead to embalming fluid seeping into the grave soil, while each gas-powered fire cremation releases around 245kg of CO2 into the atmosphere, according to UK-based cemetery and crematorium development the CDS Group. By comparison, figures from Resomation Ltd, the founding body for alkaline hydrolysis, show just 28kg of CO2 is released into the atmosphere per water cremation. Unlike conventional cremations, these eco-friendly farewells, which take between three to four hours, also don't release harmful mercury emissions into the atmosphere. A body is loaded into the alkaline hydrolysis machine, which calculates the amount of water and potassium hydroxide required. The machine locks, and an alkaline solution then fills the pressurised tank, which is gently heated to 152°C (305°F). The remains are broken into their chemical components — amino acids, peptides, sugars and salt — leaving behind a liquid that is then cooled in another tank until sterile and free from any remaining tissue or DNA. Around 330 gallons of brown-coloured liquid will be washed down the drain, while the softened bones are ground to powder in a reducer, and presented in an urn to the grieving family. Back in 2017, Wired journalist Hayley Campbell described the process in colourful detail after seeing a resomator in action at the University of California, Los Angeles (UCLA). Hayley wrote: "Over the course of up to four hours, the strong alkaline base causes everything but the skeleton to break down to the original components that built it: sugar, salt, peptides and amino acids; DNA unzips into its nucleobases, cytosine, guanine, adenine, thymine. "The body becomes fertiliser and soap, a sterile watery liquid that looks like weak tea. The liquid shoots through a pipe into a holding tank in the opposite corner of the room, where it will cool down, be brought down to an acceptable pH for the water treatment plant, and be released down the drain." Noting that "it's not actually that terrible", Hayley revealed: "The human body, liquefied, smells like steamed clams." Although many scientists view alkaline hydrolysis as the future of the death industry, it's something many still feel squeamish about, while others object on religious or cultural grounds. Highlighting why this process is still a bit of a taboo in an interview with The Telegraph, Dr Lian Lundy, a wastewater specialist from Middlesex University, explained: "Some people view it as basically mixing up my loved one with poo in the sewer and they don't like that. "But there's a lot that goes into the sewer that we don't really think about – waste from mortuaries and hospitals and all sorts of things that we don't know about – so from that perspective, it's not really any different."


Irish Examiner
14 hours ago
- Irish Examiner
‘Ticking timebomb': Sea acidity at critical levels and threatens entire ecosystems
The world's oceans are in worse health than realised, scientists have said, as they warn that a key measurement shows we are 'running out of time' to protect marine ecosystems. Ocean acidification, often called the 'evil twin' of the climate crisis, is caused when carbon dioxide is rapidly absorbed by the ocean, where it reacts with water molecules leading to a fall in the pH level of the seawater. It damages coral reefs and other ocean habitats and, in extreme cases, can dissolve the shells of marine creatures. Until now, ocean acidification had not been deemed to have crossed its 'planetary boundary'. The planetary boundaries are the natural limits of key global systems – such as climate, water and wildlife diversity – beyond which their ability to maintain a healthy planet is in danger of failing. Six of the nine had been crossed already, scientists said last year. However, a new study by the UK's Plymouth Marine Laboratory (PML), the Washington-based National Oceanic and Atmospheric Administration and Oregon State University's Co-operative Institute for Marine Resources Studies found that ocean acidification's 'boundary' was also reached about five years ago. 'Ocean acidification isn't just an environmental crisis – it's a ticking timebomb for marine ecosystems and coastal economies,' said PML's Professor Steve Widdicombe, who is also co-chair of the Global Ocean Acidification Observing Network. The study drew on new and historical physical and chemical measurements from ice cores, combined with advanced computer models and studies of marine life, which gave the scientists an overall assessment of the past 150 years. It found that by 2020 the average ocean condition worldwide was already very close to – and in some regions beyond – the planetary boundary for ocean acidification. This is defined as when the concentration of calcium carbonate in seawater is more than 20% below pre-industrial levels. The deeper in the ocean they looked, the worse the findings were, the scientists said. At 200 metres below the surface, 60% of global waters had breached the 'safe' limit for acidification. 'Most ocean life doesn't just live at the surface,' said PML's Professor Helen Findlay. 'The waters below are home to many more different types of plants and animals. Since these deeper waters are changing so much, the impacts of ocean acidification could be far worse than we thought.' As pH levels drop, calcifying species such as corals, oysters, mussels and tiny molluscs known as sea butterflies struggle to maintain their protective structures, leading to weaker shells, slower growth, reduced reproduction and decreased survival rates. The authors said decreasing CO2 emissions was the only way to deal with acidification globally, but that conservation measures could and should focus on the regions and species that were most vulnerable. The Guardian


Irish Independent
3 days ago
- Irish Independent
New initiatives needed to protect marine migration, says Irish scientist involved in global study
However, current targets on designating marine protected areas (MPAs) are not enough to halt biodiversity loss, and other measures will need to be taken, a study involving six Irish scientists showed. Named MegaMove, the sharing of data by nearly 400 scientists from over 50 countries informed the UN-backed global research, which is published in the journal Science on the eve of UN World Oceans Day tomorrow. Dr Mark Jessopp, one of six Irish-based scientists involved, all from University College Cork (UCC), said the study was the first of its type in terms of scale. 'The study's goal was to identify areas used by marine megafauna for important behaviours like foraging, resting or migratory corridors, and these areas and behaviours can only be found based on their tracked movement patterns,' he said. We will need a range of initiatives, such as changing shipping lanes and restricting some types of commercial fishing gear Dr Jessopp has expertise in the puffin, classified as endangered in Europe, which can fly vast distances from Ireland across the Atlantic in winter. The epic migration makes the birds vulnerable to a range of impacts outside Irish waters, and the study highlights the vital role of international co-ordination. Similar approaches could be taken to other marine megafauna frequenting Irish waters, such as whales and basking sharks, already protected here, and other seabirds, Dr Jessopp said. The combined research, he added, 'outlines the most important locations for 30pc area protection for global marine megafauna species, ranking them based on the largest number of species using areas for important behaviours'. 'It shows that the EU target for designating 30pc of MPAs by 2030 is a good start, but we will need a range of other initiatives, such as changing shipping lanes, restricting use of some types of commercial fishing gear and restricting placement of offshore wind projects,' Dr Jessopp said. MPAs for conservation of marine species and habitats cover 8pc of the world's oceans, which the UN High Seas Treaty wants to expand to 30pc. ADVERTISEMENT The blue sharks we tracked from Cork migrated south into the Bay of Biscay … and as far as the Canary Islands Dr Tom Doyle, also a contributor, said the study is important for Ireland in view of 'the fair share of large migratory species that use our waters'. 'For example, blue sharks migrate thousands of kilometres and can cross many different EEZs [exclusive economic zones]. The blue sharks we tracked from Cork migrated south into the Bay of Biscay, the Azores and as far as the coastal waters of Morocco and the Canary Islands,' Dr Doyle said. 'This presents a challenge for area- based conservation in terms of where to best place MPAs. 'Results from this study suggest that our animals spend most of their time in EEZs, so enhancing protection within areas of national jurisdiction and as part of a network of MPAs is one of the quickest ways to help our blue sharks and other species.' The other UCC scientists involved in the international study were Professor John Quinn, Dr Ashley Bennison, Dr Michelle Cronin and Luke Harman.