Corporate reports miss the mark on ocean health
Key Takeaways:
Amid growing scrutiny from policymakers and financiers on how corporations report their climate- and nature-related impacts, a new paper summarizes industrial impacts on the ocean and compares them with what leading companies in the ocean economy disclose.
The work shows corporations disclose little about their ocean-specific impacts, especially on biodiversity and ecosystems, and rarely set targets for reducing them.
These insights can help improve reporting frameworks with ocean-specific needs, allowing investors better understand their risks and incentivizing companies to change their practices.
Covering nearly three-quarters of the planet, the ocean may seem vast, yet it is rapidly becoming a crowded space. While it was initially slower to develop than land-based industries, the ocean economy is now surging thanks to new technologies. Companies and governments are vying for food, raw materials, energy, and geopolitical influence. In just two decades, shipping has grown fivefold and now carries 80% of global trade by volume; offshore wind has expanded more than 500 times; and nearly one million kilometers of seabed fiber-optic cables transmit 99% of international communications.
“Humanity has relied on the ocean for millennia, yet today’s scale and diversity of use are unprecedented,” said Jean-Baptiste Jouffray, a Wallenberg postdoctoral fellow at Stanford University’s Center for Ocean Solutions and the Stanford-based Natural Capital Project, and lead author of a paper out today in Nature Sustainability. “While this offers opportunities for human wellbeing, it also poses severe risks to ecosystems and the communities that depend on them.” A simple example: one new invasive species is introduced in a new part of the ocean every three days, in many cases taking over local ecosystems and fisheries and having far-reaching consequences.
In the new paper, Jouffray and his collaborators produced a typology of observed ocean impacts, summarizing and categorizing impacts from eight core sectors of the ocean economy: cruise tourism, marine equipment and construction, offshore oil and gas, offshore wind, port activities, seafood, shipbuilding and repair, and container shipping. They then analyzed annual and sustainability reports from the top 10 companies in each sector for the years 2018 - 2020 to see what impacts are being reported, how they are measured, and what targets (if any) are set.
The findings reveal crucial gaps in the current reporting of corporate impacts on marine ecosystems, and establish an important baseline for future comparisons. Companies focus almost exclusively on energy use and greenhouse gas emissions, with few measurements of more ocean-specific impacts such as habitat destruction, overfishing, underwater noise, or the spread of invasive species (see Figure 1). Where reporting does occur, companies use a wide range of indicators, hindering comparability and suggesting a lack of consensus on what should be reported. Notably, less than one-third of the companies reported indicators for biodiversity-related impacts, and none of these indicators were used by more than two companies.
How reporting can translate into regulatory and financial responses
Why go to all this effort? Once climate or nature-related information is made public, investors and lenders may find investments are too risky because of their potential impacts on other sectors or on their reputations. “In theory, the more information companies disclose about their operations, the better you can influence their behavior. But that requires someone to act on that information. Transparency alone is a necessary, but far from sufficient, basis for corporate accountability,” said Jouffray.
A number of voluntary climate and nature reporting frameworks, such as the Taskforce for Nature-Related Financial Disclosures, the World Benchmarking Alliance, and the CDP (formerly the Carbon Disclosure Project), are actively working to incorporate ocean impacts. Meanwhile, several stock exchanges now expect listed companies to disclose information on their climate impacts. Over time, such transparency could become standard, much as financial reporting is today.
Filling gaps in data and policy
The researchers have already shared their work with these reporting organizations in an effort to build consensus around which indicators to focus on. Their analysis also clarifies where there are gaps in what is being measured, and where researchers could play a bigger role in providing baseline information – for instance, when it comes to the introduction of invasive species. Eventually, some of these data may be produced by third-party monitoring systems, much as Global Fishing Watch tracks fishing vessel activity via satellite, since current reports are based on what companies choose to publish.
The investors are up next
The research team is turning next to identifying the financiers of these key ocean economy companies, hoping they can help create the right incentives for better corporate disclosure and practices. “There has been a lot of interest in the role the financial sector could play to influence ocean conservation and sustainable use, so we really want to test that idea,” said John Virdin, director of the Ocean Policy Program at the Nicholas Institute for Energy, Environment and Sustainability and a co-author of the paper. “Now that we have a baseline of the ocean impacts that companies report, we’re curious to know: if this reporting is improved, would financiers act on that information? Would it change investment decisions in the ocean economy? These are questions we are turning to now.”
This work was funded by the Knut and Alice Wallenberg Foundation (2021.0343), the Packard Foundation (2022-73546), and the Walton Family Foundation (00104857).
Jouffray is also affiliated with the King Center on Global Development at Stanford and the Stockholm Resilience Centre at Stockholm University. Virdin is also affiliated with Duke’s Nicholas School of the Environment. Other co-authors are Jan Bebbington of the Pentland Centre for Sustainability in Business at Lancaster University; Robert Blasiak of the Stockholm Resilience Centre at Stockholm University; Andrea Dunchus and Dan Vermeer with the Duke University Fuqua School of Business; Marta Lo Presti, Jeremy Pare, Juan Pablo Quintero and Regan Rosenthal with the Duke University Nicholas School of the Environment; Daniel Prosi with the European University Institute, Department of Economics; and Piera Tortora with the Organisation for Economic Co-operation and Development.
Journal
Nature Sustainability
Article Title
Identifying and closing gaps in corporate reporting of ocean impacts
Article Publication Date
8-Sep-2025
Ocean warming puts vital marine microbe Prochlorococcus at risk
University of Washington
image:
The lines on the map are cruise tracks, overlaying temperature. The water in yellow areas hovers around 86 degrees while the temperature at the poles is closer to 32. Researchers cataloged Prochlorococcus abundance using SeaFlow continuous flow cytometry along the path of the lines.
view moreCredit: François Ribalet/University of Washington
Among the tiniest living things in the ocean are a group of single celled microbes called Prochlorococcus. They are cyanobacteria, also known as blue-green algae, and they supply nutrients for animals all the way up the food chain. Over 75% of surface waters teem with Prochlorococcus, but as ocean temperatures rise, researchers fear that the water might be getting too warm to support the population.
Prochlorococcus is the most abundant photosynthesizing organism in the ocean, accounting for 5% of global photosynthesis. Because Prochlorococcus thrive in the tropics, researchers predicted that they would adapt well to global warming. Instead, a new study finds that Prochlorococcus prefers water between 66 and 86 degrees and doesn’t tolerate water much warmer. Climate models predict that subtropical and tropical ocean temperatures will exceed that threshold in the next 75 years.
“For a long time, scientists thought Prochlorococcus was going to do great in the future, but in the warmest regions, they aren’t doing that well, which means that there is going to be less carbon — less food — for the rest of the marine food web,” said François Ribalet, a University of Washington research associate professor of oceanography, who led the study.
Their results were published in Nature Microbiology on Sept. 8.
In the past 10 years, Ribalet and colleagues have embarked on close to 100 research cruises to study Prochlorococcus. His team has analyzed approximately 800 billion Prochlorococcus-sized cells across 150,000 miles around the world to figure out how they are doing and whether they can adapt.
“I had really basic questions,” Ribalet said. “Are they happy when it's warm? Or are they not happy when it's warm?” Most of the data comes from cells grown in culture, in a lab setting, but Ribalet wanted to observe them in their natural ocean environment. Using a continuous flow cytometer — called SeaFlow — they fired a laser through the water to measure cell type and size. They then built a statistical model to monitor cell growth in real time, without disturbing the microbes.
Results showed that the rate of cell division varies with latitude, possibly due to the amount of nutrients available, sunlight or temperature. The researchers ruled out nutrient levels and sunlight before zeroing in on temperature. Prochlorococcus multiply most efficiently in water that is between 66 and 84 degrees, but above 86, rates of cell division plummeted, falling to just one-third of the rate observed at 66 degrees. Cell abundance followed the same trend.
In the ocean, mixing transports most nutrients to the surface from the deep. This occurs more slowly in warm water, and surface waters in the warmest regions of the ocean are nutrient-scarce. Cyanobacteria are one of the few microbes that have adapted to live in these conditions.
“Offshore in the tropics, the water is this bright beautiful blue because there’s very little in it, aside from Prochlorococcus,” Ribalet said. The microbes can survive in these areas because they require very little food, being so small. Their activity supports most of the marine food chain, from small aquatic herbivores to whales.
Over millions of years, Prochlorococcus has perfected the ability to do more with less, shedding genes it didn’t need and keeping only what was essential for life in nutrient-poor tropical waters. This strategy paid off spectacularly, but now, with oceans warming faster than ever before, Prochlorococcus is constrained by its genome. It can’t retrieve stress response genes discarded long ago.
“Their burnout temperature is much lower than we thought it was,” Ribalet said. The previous models assumed that the cells would continue dividing at a rate that they can’t sustain because they lack the cellular machinery to cope with heat stress.
Prochlorococcus is one of two cyanobacteria that dominate tropical and subtropical waters. The other, Synechococcus, is larger, with a less streamlined genome. The researchers found that although Synechococcus can tolerate warmer water, it needs more nutrients to survive. Should Prochlorococcus numbers dwindle, Synechococcus could help fill the gap, but it isn’t clear what the impact of this would be on the food chain.
“If Synechococcus takes over, it’s not a given that other organisms will be able to interact with it the same way they have interacted with Prochlorococcus for millions of years,” Ribalet said.
Climate projections estimate ocean temperatures based on greenhouse gas emission trends. In this study, the researchers tested how Prochlorococcus might fare in moderate- and high-warming scenarios. In the tropics, modest warming could reduce Prochlorococcus productivity by 17%, but more advanced warming would decimate it by 51%. Globally, the moderate scenario produced a 10% decline while warmer forecasts reduced Prochlorococcus by 37%.
“Their geographic range is going to expand toward the poles, to the north and south,” Ribalet said. “They are not going to disappear, but their habitat will shift.” That shift, he added, could have dramatic implications for subtropical and tropical ecosystems.
Still, the researchers acknowledge the limitations of their study. They couldn’t study every cell or sample every body of water. Their measurements are based on pooled samples, which could mask the presence of a heat-tolerant strain.
“This is the simplest explanation for the data that we have now,” Ribalet said. “If new evidence of heat tolerant strains emerges, we’d welcome that discovery. It would offer hope for these critical organisms.”
Co-authors include E. Virginia Armbrust, a UW professor of oceanography; Stephanie Dutkiewicz, a senior research scientist in the Center for Sustainability Science and Strategy at MIT; and Erwan Monier, co-director of the Climate Adaptation Research Center and an associate professor in the Department of Land, Air and Water Resources at UC Davis.
This research was funded by the Simons Foundation and other government, foundation and industry funders of the MIT Center for Sustainability Science and Strategy.
For more information, contact Ribalet at ribalet@uw.edu.
This image, captured by an electron microscope, displays individual Prochlorococcus cells. Each blob is a microbe, measuring just 500 nanometers in diameter. For reference, the width of a single human hair is around 100,000 nanometers.
Credit
Natalie Kellogg/University of Washington
Sunset from the research vessel Thomas G. Thompson, which housed the SeaFlow flow cytometer during data collection cruises.
Sunset aboard the Thomas G. Thompson, a University of Washington-operated research vessel equipped for ocean voyages. The instrument visible on the left is a water sampler that can collect from different depths, the SeaFlow flow cytometer was also aboard, but not pictured here.
Credit
Kathy Newer/University of Washington
Journal
Nature Microbiology
Method of Research
Experimental study
Subject of Research
Cells
Article Title
Future Ocean Warming May Cause Large Reductions in Prochlorococcus Biomass and Productivity
Article Publication Date
8-Sep-2025
