Sharks rarely seen together may be up for sharing a meal too good to miss

Oceanic whitetip and tiger sharks peacefully co-fed on a carcass close to Hawaii’s Big Island. Such extremely rare observations could help scientists understand shark ecology better.

Frontiers

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At least nine oceanic whitetip sharks and five tiger sharks were spotted feeding on the carcass. Credit: Kayleigh Grant.

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Credit: Kayleigh Grant

Many sharks, particularly those that live in the open oceans, are hunters rather than scavengers. Despite this, a small portion of their diet comes from scavenging, a behavior they may engage in when the opportunity arises.

Now, writing in Frontiers in Fish Science, researchers have described an unusual aggregation of sharks coming together to feed on a carcass that had decayed to mostly flesh and blubber.

“To our knowledge, this is the first study to document a feeding aggregation of tiger sharks and oceanic whitetip sharks scavenging concurrently, and peacefully, on a carcass,” said first author Dr Molly Scott, a marine researcher at the University of Hawaiʻi at Mānoa. “These species are rarely seen together in the wild because of the vastly different habitats they occupy.”

Feast in peace

Oceanic whitetips, a threatened species growing to an average of two meters in length, are solitary sharks, highly migratory, and spend most of their time roaming the oceans. This choice of habitat makes them difficult to study. During the spring and summer, however, they seasonally aggregate at Hawaii’s Big Island. Tiger sharks, a slightly bigger, more coastal species growing three to four meters on average, dwell there year-round. “It is incredibly rare for these two species to overlap in space and time,” Scott said.

In April 2024, a tourist boat sighted a heavily decayed carcass about 10 kilometers off the west coast of Big Island. Once in the water, the tourist operators could observe the feeding event for 8.5 hours. During this time, at least nine oceanic whitetip sharks and five tiger sharks were spotted.

“Even though up to 12 individual sharks were feeding intermittently from a very small, highly degraded carcass we did not observe any agonistic inter- or intra-species aggression,” Scott said. “This was surprising to me; I would assume some agonistic behaviors would exist when there are that many sharks attempting to feed around such a small carcass. But it seems all individuals knew their place in the social hierarchy.”

First servings

Tiger sharks, most likely due to their larger size, were the dominant species. All tiger sharks, except one smaller female, and the two largest oceanic whitetips were observed most frequently feeding directly on the carcass. The smaller sharks stayed under the surface and fed on scraps drifting away. It is possible that they were attracted to the scene because of the scraps and regurgitations left behind by the larger tiger sharks, the researchers said.

There might have been other reasons for some sharks getting first servings, too. “Some individuals, like the female tiger shark, may have been shier or less bold, likely again due to her size. Also, with the other sharks having established the feeding hierarchy before the female tiger shark arrived, maybe she didn’t feel too welcome to get in on the action,” Scott explained.   

The study was conducted over a relatively short time span as the carcass could not be located again the next day. Considering the size of the carcass, a lot of sharks were present, and this research could provide new insights into relationships and social interactions between sharks that don’t normally inhabit the same waters, the researchers said.

For humans, they said, it can perhaps provide a new perspective on sharks. “There were between two and three humans in the water at all times filming more than 12 sharks feeding. None of the photographers reported any scary, aggressive, or harmful interactions with the sharks,” Scott concluded. “I hope this provides a new perspective that sharks are not the human-eating predators they are made out to be.”

Female oceanic whitetip shark seen feeding on the carcass. 

Image: Kayleigh Grant.

Feeding shark [VIDEO] |

Feeding shark. Credit: Kayleigh Grant. 

Feeding sharks [VIDEO] |

The feeding event could be observed for 8.5 hours. Credit: Kayleigh Grant. 

Feeding sharks [VIDEO] | 

Up to 12 individual sharks were feeding intermittently from a very small, highly degraded carcass. No agonistic inter- or intra-species aggression was observed. Credit: Kayleigh Grant. 

Feeding sharks [VIDEO] | 

Up to 12 individual sharks were feeding intermittently from a very small, highly degraded carcass. No agonistic inter- or intra-species aggression was observed. Credit: Kayleigh Grant.

Male tiger shark at the scene. Image: Andrew Aggergaard.

Journal

Frontiers in Fish Science

DOI

10.3389/frish.2025.1520995 

Method of Research

Observational study

Subject of Research

Animals

Article Title

Novel observations of an oceanic whitetip and tiger shark scavenging event

Article Publication Date

29-May-2025

 

Could ‘pausing’ cell death be the final frontier in medicine on Earth and beyond?

University College London

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Illustration of a healthy cell (left) alongside a cell that has been affected by necrosis (right).

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Credit: LinkGevity

The process of necrosis, a form of cell death, may represent one of the most promising ways to change the course of human aging, disease and even space travel, according to a new study from researchers at UCL, drug discovery company LinkGevity and the European Space Agency (ESA).

In the study, published in Nature Oncogene, a world-leading international team of scientists and clinicians explore the potential of necrosis – when cells die unexpectedly as a result of infection, injury or disease – to reshape our understanding and treatment of age-related conditions.

Challenging prevailing views, the paper brings together evidence from cancer biology, regenerative medicine, kidney disease, and space health to argue that necrosis is not merely an endpoint, but a key driver of aging that presents an opportunity for intervention.

Dr Keith Siew, an author of the study from UCL Centre for Kidney & Bladder Health, said: “Nobody really likes talking about death, even cell death, which is perhaps why the physiology of death is so poorly understood. And in a way necrosis is death. If enough cells die, then tissues die, then we die. The question is what would happen if we could pause or stop necrosis.”

Dr Carina Kern, lead author of the study and CEO of LinkGevity, a biotech company based at Cambridge’s Babraham Research Campus and part of the NASA Space-Health program, said: “Necrosis remains one of the last frontiers in medicine – a common thread across aging, disease, space biology, and scientific progress itself.”

Cells are the fundamental building blocks of life and can die in various ways. ‘Programmed’ forms of cell death are beneficial, carefully orchestrated processes that allow our tissues to replenish themselves and function well throughout life.

But ‘unprogrammed’ cell death, or necrosis, is an uncontrolled and catastrophic process that leads to tissue degeneration and biological decline.

At the centre of the necrotic process is calcium, a vital resource that effectively controls the cell by determining which functions are switched on or off. Calcium ions are normally maintained at a level that is 10,000 to 100,000 times higher outside the cell than inside of it.

When this finely tuned balance fails, calcium floods the cell like an electrical short circuit, pushing the cell into chaos. Unlike programmed death, where cells dismantle in an orderly manner, necrosis causes cells to rupture, spilling toxic molecules into surrounding tissues.

This sparks a chain reaction that causes widespread inflammation and affects tissue repair, creating a snowball effect that ultimately leads to frailty and the onset of chronic age-related conditions such as kidney disease, heart disease and Alzheimer’s.

Dr Siew added: “When cells die, it’s not always a peaceful process for the neighbours.”

Dr Kern explains: “Necrosis has been hiding in plain sight. As a final stage of cell death, it’s been largely overlooked. But mounting evidence shows it’s far more than an endpoint. It’s a central mechanism through which systemic degeneration not only arises but also spreads. That makes it a critical point of convergence across many diseases. If we can target necrosis, we could unlock entirely new ways to treat conditions ranging from kidney failure to cardiac disease, neurodegeneration, and even aging itself.”

Notably, it is in the kidneys that necrosis may have its most devastating and underappreciated impact. Necrosis induces kidney disease, which can lead to kidney failure requiring a transplant or dialysis. By age 75 nearly half of all individuals develop some degree of kidney disease as part of the natural aging process.

Dr Siew added: “With kidney disease, there’s no one underlying reason that the kidneys fail. It could be a lack of oxygen, inflammation, oxidative stress, a build-up of toxins, and so on. All of these stressors eventually lead to necrosis, which initiates a positive feedback loop that spirals out of control, leading to kidney failure. We can’t stop all of these stressors, but if you could intervene at the point of necrosis, you’d effectively achieve the same result.”

Another area where interrupting necrosis could have a big impact is spaceflight, where astronauts often experience accelerated aging and kidney-related decline due to the effects of low gravity and exposure to cosmic radiation. A 2024 study involving Dr Siew demonstrated that the human kidney may be the ultimate bottleneck for long-duration space missions.

The authors say finding solutions to this accelerated aging and kidney disease may be the final frontier for human deep space exploration.

Professor Damian Bailey, an author of the paper from the University of South Wales and Chair of the European Space Agency (ESA) Life Sciences Working Group, said: “Targeting necrosis offers potential to not only transform longevity on Earth but also push the frontiers of space exploration. In space, the same factors that cause aging on Earth are made worse by cosmic radiation and microgravity – speeding up degeneration dramatically.”

Dr Kern added: “In many age-related diseases – affecting diverse organs such as the lungs, kidneys, liver, brain, and cardiovascular system – relentless cascades of necrosis fuel the progression of disease. This is often alongside impaired healing that leads to fibrosis, inflammation and damaged cells. Each cascade triggers and amplifies the next.

“If we could prevent necrosis, even temporarily, we would be shutting down these destructive cycles at their source, enabling normal physiological processes and cell division to resume – and potentially even allowing for regeneration.”

The paper is a collaborative effort by clinicians and scientists from institutions including UCL Division of Medicine, Harvard Medical School-affiliated Brigham and Women’s Hospital, Mayo Clinic, NASA Space-Health program, MRC Laboratory of Molecular Biology, University of South Wales, and the European Space Agency.

Necrosis in lab grown cells [VIDEO] | 

The video shows a cluster of cells growing in the lab, before necrosis occurs and a necrotic core (red area) forms and spreads.

Credit

LinkGevity

Publication:

Carina Kern et al. ‘Necrosis as a fundamental driver of loss of resilience and biological decline: What if we could intervene?’ is published in Nature Oncogene and is strictly embargoed until Thursday 29 May at 08:00 BST / 03:00 ET.

DOI: https://doi.org/10.1038/s41388-025-03431-y

About UCL – London’s Global University

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Since 1826, we have championed independent thought by attracting and nurturing the world's best minds. Our community of more than 50,000 students from 150 countries and over 16,000 staff pursues academic excellence, breaks boundaries and makes a positive impact on real world problems.

The Times and Sunday Times University of the Year 2024, we are consistently ranked among the top 10 universities in the world and are one of only a handful of institutions rated as having the strongest academic reputation and the broadest research impact.

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We were the first in England to welcome women to university education and that courageous attitude and disruptive spirit is still alive today. We are UCL.

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Journal

Oncogene

DOI

10.1038/s41388-025-03431-y 

Method of Research

Literature review

Subject of Research

People

Article Title

Necrosis as a fundamental driver of loss of resilience and biological decline: What if we could intervene?’

Article Publication Date

29-May-2025

 

New research shows importance of promoting better understanding and inclusion of children with disabilities in the classroom

Q&A with Child Development journal author

Society for Research in Child Development

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According to the National Center on Birth Defects and Developmental Disabilities, approximately 1 in 6 children in the United States have developmental disabilities which include physical, learning, language or behavior-related disabilities. Students with disabilities often receive accommodations (how students access and learn the same content as their classmates) at school, but teachers rarely explain them to typically-developing classmates. Children with disabilities are increasingly included in general education classrooms alongside typically-developing classmates. Accommodations such as an adult helper to work one-on-one with the student, preferential seating, or extra time to navigate the school between classes ensure the success of many children with disabilities in these settings. When teachers do not discuss accommodations or their purpose with typically-developing classmates, those classmates may have to make sense of the accommodations themselves.

The current study examined how five to nine-year-olds evaluate children with disabilities who engage in accommodation-related behavior (e.g., taking extra time on tests/assignments, going to lunch/recess early, playing games differently). The study included 122 children ranging from 5- to 9- years (61 males; 61 females) who lived in Tennessee or had recently moved from Tennessee to another state in the United States. The majority of the participants were white with upper-middle-class backgrounds (87.7%), followed by Asian/Asian American (9.8%), Hispanic or Latino (4.1%), Black/African American (3.3%), and Native American (.8%). (These categories were not mutually exclusive; parents could select more than one.) Most parents reported that their highest level of education was a master’s degree (36.9%). An experimenter showed children a slideshow where several characters with either physical (walking) or cognitive (learning) disabilities engaged in physical accommodations (e.g., goes outside to recess first) or cognitive accommodations (e.g., has an adult helper in class). Participants were asked to evaluate the fairness of these accommodations, and to provide their explanations for why characters engaged in these accommodation-related behaviors.

The findings showed that with increasing age, children evaluated disability-related accommodations as increasingly fair. Older children also demonstrated greater understanding of how specific accommodations help to address specific needs, which might account for why they judged accommodations as fairer.  The research was featured in a new Child Development article with authors from Vanderbilt University, in the United States. 

These findings may encourage teachers, parents, and service providers to discuss the ways that accommodations address the needs of persons with disabilities. The Society for Research in Child Development (SRCD) had the opportunity to speak with lead author Dr. Nicolette G. Granata to learn more about the research. 

SRCD: Can you please provide a brief overview of the study?

Dr. Granata: In this study, we investigated how young children, 5-9-years-old, evaluate the fairness of and explain accommodations that are common in elementary school classrooms, such as playing games or sports differently, going to recess or lunch first, or receiving extra help in the classroom. Children reasoned about other children with either physical (walking) or cognitive (learning disabilities) engaging in walking-related (e.g., playing soccer with one’s hands) or learning-related classroom accommodations (e.g., having an adult helper with classwork), and were asked to imagine that they were a part of this classroom, too. Children first provided their reasoning for why these other children in the hypothetical classroom may have engaged in these behaviors and then evaluated whether these behaviors were fair or not, on a scale from “very unfair” to “very fair”. We were interested in children’s evaluations of the accommodation-related behaviors, their explanations for the behaviors, and the associations between their evaluations and reasoning.  

SRCD: Did you learn anything that surprised you? 

Dr. Granata: Absolutely! Regardless of age, children who accounted for accommodation-related behaviors (like going to recess first) in terms of addressing the needs of children with disabilities (versus their wants or desires), evaluated that behavior as more fair. We were surprised that this was the case whether children could articulate exactly why a certain character with a disability needed an accommodation (“he needs to go outside first because he can’t walk as well and it takes him longer than other kids”), or, simply understood that a need was present (“because he needs to”). Why does this matter? Because it means that children may not need to know all the details about a particular disability or accommodation to demonstrate flexibility, understanding, and acceptance. 

SRCD: Can you please explain how this research might be helpful for teachers, parents and administrators?

Dr. Granata: My sense of why many teachers feel wary to formally discuss disability in the classroom is because they fear that children won’t understand the nuances of the many types of disabilities their classmates may have, or that children might resent their classmates for having certain accommodations, or that pointing out a disability might lead to children treating the disabled classmate negatively.  This study demonstrates that even young children generally felt neutral about the fairness of unexplained accommodations for classmates with disabilities, and children who were older or who expressed an understanding that accommodations addressed people’s needs generally evaluated the accommodations as fair. Thus, this study demonstrates to teachers, parents, and administrators that it might be worthwhile to begin these discussions in elementary school, emphasizing how accommodations work to address the unique needs of persons with disabilities. Children are likely noticing disabilities and accommodations anyway, and are likely curious about the reasons for accommodations, so why not help guide children with accurate and empathic information?  

SRCD: Can you please address some of the research limitations? 

Dr. Granata: Some limitations of our study were that disabilities were only described to children (“He walks differently”) rather than visually depicted, meaning children may have interpreted the severity of any given disability differently. This was an intentional methodological decision, but this is of course not how most children will witness persons with disabilities in the real-world. As well, exploratory analyses in our study revealed that children who more often interacted with persons with disabilities evaluated accommodations more fairly; because our sample was largely middle to upper-middle class, perhaps children in our study had more exposure to accommodations and other disability-related services than participants from lower income communities, leading to their generally neutral or positive evaluations of the fairness of accommodations. We need to know more about how children in different communities evaluate and reason about the fairness of disability accommodations.

SRCD: What’s next in this field of research?

Dr. Granata: Future research should continue to explore how children evaluate and reason about the fairness of accommodations for people with disabilities in more diverse samples, as well as more specifically examine how children’s evaluations of accommodations vary along with what they are taught in school – both explicitly and implicitly. Children’s concepts of disabled persons continue to be understudied when compared to their concepts of other minority groups; we encourage continued study in this field in order to build a more inclusive and accepting society for those with differences throughout the lifespan.

Summarized from an article in Child Development, “Developments in Children’s Evaluations of and Reasoning about Disability-Related Accommodations,” Granata, N., Bacchus, C., Leguizamon, M., and Lane, J.D. (Vanderbilt University). Copyright 2025 The Society for Research in Child Development. All rights reserved.

 

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Journal

Child Development

DOI

10.1111/cdev.14255 

Method of Research

Experimental study

Subject of Research

People

Article Title

Developments in Children's Evaluations of and Reasoning About Disability-Related Accommodations

Article Publication Date

29-May-2025

 

Report: ‘Future-proofing’ crops will require urgent, consistent effort

Expert describes tools, techniques and challenges

University of Illinois at Urbana-Champaign, News Bureau

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In a review, University of Illinois Urbana-Champaign professor Stephen Long describes potential methods for “future-proofing” crops against climate change.

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Credit: Photo by Fred Zwicky

CHAMPAIGN, Ill. — In a review in The Philosophical Transactions of the Royal Society B, Stephen Long, a professor of crop sciences and of plant biology at the University of Illinois Urbana-Champaign, describes research efforts to “future-proof” the crops that are essential to feeding a hungry world in a changing climate. Long, who has spent decades studying the process of photosynthesis and finding ways to improve it, provides an overview of key scientific findings that offer a ray of hope.

Higher temperatures, more frequent and longer droughts, catastrophic rainfall events and rising atmospheric carbon dioxide levels all influence the growth, development and reproductive viability of crop plants, he writes. While some plants and regions may benefit from some aspects of climate change, without prolonged and costly intervention, many more will suffer potentially catastrophic declines.

“By 2050-60, crops will experience a significantly different environment from today,” Long writes. From its pre-industrial level of about 200 parts per million, “atmospheric CO2 reached 427 ppm in 2024 and is projected to be about 600 ppm by 2050.”

Extreme heat, droughts, floods and other climate-related events are already disrupting agricultural systems. Projected temperature extremes and climate instability will further reduce crop yields, increasing starvation, political unrest and mass migration, he writes.

There is some hope, however. It may be possible to alter crops in ways that allow them to persist and perhaps even increase yields despite the challenges, Long said. While the process takes time and can be costly, the work has already begun.

For example, researchers are evaluating the heat-, drought- and flood-tolerance of different varieties of specific crop plants, identifying those with potentially beneficial attributes. Discovering the genetic traits that confer these benefits will allow scientists to develop crops — through plant breeding and/or genetic engineering — that can better withstand the extremes.

Through painstaking work, scientists have discovered that some rice varieties can survive up to two weeks of submergence during periods of intense flooding, while other varieties are more heat tolerant than others. The findings offer opportunities to develop hardier cultivars.

Plants must withstand an array of challenges as temperatures rise. The drying capacity of the atmosphere, which increases with temperature, draws moisture out of plant leaves through tiny pores called stomata. This reduces plant water-use efficiency, Long said, straining already scarce water resources in many parts of the globe.

“A plant may partially close its stomata to retain moisture, but this can interfere with its ability to draw carbon dioxide from the atmosphere, a key step in photosynthesis,” Long said.

In laboratory and field experiments, researchers found that increasing the expression of the gene for a sensor protein found in plants reduced water loss through stomata without interfering with photosynthesis.

“The result was a 15% improvement in leaf-level water-use efficiency in field-grown tobacco and a 30% decrease in whole plant water use,” Long wrote. Because of the high speed with which it can be genetically modified, tobacco is often used as a “test-bed” for studying alterations that can be used in a variety of other plants.

Researchers also have found ways to reduce the density of stomata on the leaves of rice and wheat, improving water-use efficiency by 15-20% with no decrease in yield.

High carbon dioxide on its own alters plant physiology, sometimes in beneficial ways by boosting photosynthesis, but also in detrimental ways, Long said. High CO2 can change plant metabolic control by altering levels of key enzymes. Scientists have found that adjusting the levels of proteins that regulate rubisco, a key photosynthetic enzyme, can boost photosynthetic efficiency in the presence of high CO2.

To demonstrate what kinds of gains are possible in food crops, Long points to the remarkable progress made in research on maize, nearly 80% of which is used in ethanol production and to feed animals, not humans.

“Between 1980 and 2024, U.S. maize yields doubled while sorghum improved just 12%,” he said. The success in maize is the result of massive investments from large multinational companies. The same investments are not yet being made on the public domain side of the equation.

Without similar investment, “it is hard to see how the opportunities … for future-proofing our crops can be implemented at the scale that is necessary,” he writes.

Long also is a professor in the Carl R. Woese Institute for Genomic Biology at the U. of I.  He is supported by Gates Agricultural Innovations and the Department of Energy Center for Advanced Bioenergy and Bioproducts Innovation.

Editor’s note:  

To reach Stephen Long, email slong@illinois.edu.  

Prior to publication, the paper “Needs and opportunities to future-proof crops and the use of crop systems to mitigate atmospheric change” is available to reporters from the U. of I. News Bureau.

DOI: 10.1098/rstb.2024.0229

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Journal

Philosophical Transactions of the Royal Society B Biological Sciences

DOI

10.1098/rstb.2024.0229 

Method of Research

Systematic review

Subject of Research

Not applicable

Article Title

Needs and opportunities to future-proof crops and the use of crop systems to mitigate atmospheric change

Article Publication Date

29-May-2025

 

Atlantic ocean current unlikely to collapse with climate change

California Institute of Technology

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The Atlantic meridional overturning circulation, commonly referred to as the “AMOC,” is a system of ocean currents confined to the Atlantic basin that plays a crucial role in regulating Earth’s climate by transporting heat from the Southern to the Northern Hemisphere. The AMOC also modulates regional weather, from the mild summers in Europe to the monsoon seasons in Africa and India. Climate models have long predicted that global warming will cause the AMOC to weaken, with some projecting substantial weakening amounting to a near-collapse relative to the AMOC’s strength today. Such a weakening would have far-reaching consequences, including changes in regional sea level rise and major shifts in regional climate, such as colder conditions in northern Europe and drier weather in parts of the Amazon and West Africa.

However, a new study from Caltech finds that although the AMOC will weaken under global warming, it is likely to do so to a much lesser extent than current projections suggest. The team developed a simplified physical model based on fundamental principles of ocean circulation—specifically, how density differences and the AMOC’s depth are related—that also incorporates real-world measurements of the ocean current’s strength, collected over 20 years through the use of monitoring arrays and other observationally constrained products of the Atlantic basin. The researchers found that the AMOC will weaken by around 18 to 43 percent at the end of the 21st century. While this does represent some weakening, it does not represent substantial weakening that the more extreme climate model projections suggest. This new understanding significantly narrows the range of future AMOC weakening, addressing a long-standing uncertainty in climate science.

The study is described in a paper appearing in the journal Nature Geoscience. The research was conducted in the laboratories of Tapio Schneider, the Theodore Y. Wu Professor of Environmental Science and Engineering; and Andrew Thompson, the John S. and Sherry Chen Professor of Environmental Science and Engineering, director of The Ronald and Maxine Linde Center for Global Environmental Science, and executive officer for Environmental Science and Engineering.

Paleoclimate records, like ocean sediments that record past climate conditions, indicate that the AMOC has experienced weakening in the past, such as during the Last Glacial Maximum (a period about 20,000 years ago), leading to major swings in the climate that affected North America and Europe. Contemporary climate models show wide variation in their 21st century projections of AMOC weakening: Some predict substantialAMOC weakening, while others predict only a small amount of weakening. The new study, led by former graduate student Dave Bonan (PhD ’25), aimed to better understand the physical mechanisms governing AMOC behavior in climate models, with the goal of reconciling these discrepancies. 

The research sheds light on a long-standing and previously unexplained feature of climate models: the link between the present-day and future strength of the AMOC. Climate models that simulate a stronger present-day AMOC tend to project greater weakening under climate change. The researchers found that this relationship stems from the depth of the AMOC. A stronger AMOC typically extends to greater depths and allows changes in surface water temperature and salinity properties—caused by global warming and freshwater input—to penetrate deeper into the ocean and drive greater weakening. In other words, a climate model with a stronger and deeper AMOC is less resilient to surface changes and experiences proportionally more AMOC weakening than one with a shallower current. Climate models with a shallower present-day AMOC still show weakening under climate change, but to a lesser extent than those with a deeper present-day AMOC.

The new study uses this understanding to constrain future AMOC projections by building a simplified physical model and incorporating real-world measurements of the ocean current’s strength. The results indicate that the AMOC will only experience limited weakening even in the highest emissions scenarios. The study suggests that much of the previous uncertainty and some of the more extreme AMOC weakening projections stemmed from biases in how climate models simulate the ocean's current state, particularly its density stratification. 

“Our results imply that, rather than a substantial decline, the AMOC is more likely to experience a limited decline over the 21st century—still some weakening, but less drastic than previous projections suggest,” Bonan says.

Bonan emphasizes the need to examine higher-resolution climate models that also include more sophisticated processes. Higher-resolution models might offer deeper insights into AMOC behavior and improve projections of its future changes. The study provides a framework to interrogate and evaluate more sophisticated models.

While conducting this research at Caltech, Bonan was funded by the National Science Foundation Graduate Research Fellowship Program (NSF-GRFP).

“The NSF-GFRP gave me the freedom to tinker and explore,” he says. “There is immense value in doing basic research — it can give us a better indication of what the future might look like, as our study shows.”

The paper is titled “Observational constraints imply limited future Atlantic meridional overturning circulation weakening.” In addition to Bonan, Schneider, and Thompson, co-authors are Laure Zanna of New York University, Kyle Armour of the University of Washington, and Shantong Sun of Laoshan Laboratory in Qingdao, China. Funding was provided by the NSF, the David and Lucile Packard Foundation, and Schmidt Sciences LLC.

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Journal

Nature Geoscience

DOI

10.1038/s41561-025-01709-0 

Article Title

Observational constraints imply limited future Atlantic meridional overturning circulation weakening

Article Publication Date

29-May-2025