Electric vehicle transition could create unwanted air pollution hotspots in China and India

Princeton University, Engineering School

 

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Photo illustration by Bumper DeJesus, Princeton University.

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Credit: Bumper DeJesus, Princeton University

While electric vehicles have become a cornerstone of the global energy transition, new research led by Princeton University has demonstrated that refining the critical minerals needed for electric vehicle batteries could create pollution hotspots near manufacturing hubs.

Focusing on China and India, the researchers found that national sulfur dioxide (SO2) emissions could increase by up to 20% over current levels if the countries were to fully domesticize their supply chains for electric vehicles. The overwhelming majority of those SO­2 emissions would come from refining and manufacturing nickel and cobalt — important minerals for today’s electric vehicle batteries.

“Many discussions about electric vehicles focus on minimizing emissions from the transport and power sectors,” said corresponding author Wei Peng, an assistant professor of public and international affairs and the Andlinger Center for Energy and the Environment. “But we show here that the impacts of electric vehicles don’t end with vehicle tail-pipe emissions or electricity. It’s also about your entire supply chain.”

Publishing their findings in Environmental Science & Technology, the researchers argued that countries must think strategically about building clean supply chains as they develop decarbonization plans.

 In the case of battery manufacturing, the team underscored the importance of developing and enforcing strict air pollution standards to avoid unintended consequences of the transition to electric vehicles. They also suggested the development of alternative battery chemistries to avoid the process-based SO2 emissions of manufacturing today’s batteries.

“If you dig deep enough into any clean energy technology, you will find there are challenges or tradeoffs,” said first author Anjali Sharma, who completed the work as a postdoctoral researcher in Peng’s group and is now an assistant professor in the Centre for Climate Studies and Ashank Desai Centre for Policy Studies at the Indian Institute of Technology, Bombay. “The existence of these tradeoffs doesn’t mean that we stop the energy transition, but it does mean that we need to act proactively to mitigate these tradeoffs as much as possible.”

A tale of two countries

Both China and India have good reasons to avoid SO2 emissions: the compound is a precursor to fine particulate matter, contributing to a host of cardiovascular and respiratory problems. The two countries already suffer from high levels of air pollution. In 2019 alone, around 1.4 million premature deaths in China and around 1.7 million premature deaths in India were attributable to fine particulate matter exposure.

However, the two countries are at different stages of development for electric vehicles. Peng said that in China, a domestic supply chain for electric vehicles is the status quo, but that India is still in the early stages of supply chain development. The comparison helped the researchers identify near-term priorities as they continue or begin to build a domestic supply chain for electric vehicles.

“China needs to be thinking about how to clean up a supply chain that already exists, while India has the opportunity to build a better supply chain from the ground up,” said Peng, who is also a core faculty at the Center for Policy Research on Energy and the Environment. “Both situations come with their own challenges and opportunities.”

In India, the lowest-hanging fruit would be to focus first on cleaning up pollution from the power sector. This would require enforcing stringent SO2 pollution control measures for thermal power plants, using mature technologies like flue-gas desulfurization. For China, which already has stringent emissions controls for the power sector, the focus needs to shift to mitigating SO2 emissions from the battery manufacturing process, which the researchers said is less familiar.

However, the researchers underscored that ignoring emissions from battery manufacturing would be a critical misstep. In scenarios where China and India fully onshored their supply chains, prioritizing a cleaner grid did little to nothing to lower SO2 emissions. Instead, only scenarios focused on cleaning up battery manufacturing processes avoided SO2 pollution hotspots.

“People generally assume the transition to a greener technology is always going to be a win-win — there will be climate and air quality benefits,” said Sharma. “But without considering manufacturing, you might lower carbon and nitrogen oxide emissions but end up increasing the air pollution burden for communities near manufacturing centers.”

Human-centered approaches to decarbonization

While the analysis focused on China and India, the researchers argued that if left unaddressed, pollution from battery manufacturing will become an increasingly global challenge as electric vehicle adoption rates rise. Even if countries like China and India were to outsource battery manufacturing, Sharma said that without strategies to mitigate SO2 emissions, they would simply be offloading the problem to another country.

“It’s important to look at electric vehicles from a global supply chain perspective,” Sharma said. “Even if India were to decide against building a domestic supply chain and instead chose to import them from somewhere else, the pollution wouldn’t go away. It would just be outsourced to another country.”

In addition to their policy recommendation for proactive air pollution standards, which would likely happen at the national or subnational level, the researchers also examined how changing the battery chemistry in electric vehicles could avoid unwanted SO2 emissions at a more global scale.

While most electric vehicle batteries today rely on cobalt and nickel, the rise of alternative chemistries that use iron and phosphate (so-called lithium iron phosphate batteries) could circumvent some of the concerns associated with mining and refining cobalt and nickel. By avoiding the two minerals, scenarios with high penetration of lithium phosphate batteries resulted in far fewer SO2 emissions from manufacturing.

In all events, Peng said the findings serve as a reminder to keep people at the top of mind when designing decarbonization plans, as even the most promising technologies could come with unwanted and unintended consequences.

“We know about many of the important technologies for cutting carbon emissions,” said Peng. “But the other part is how people will be affected by those technologies. My approach is to think about the best ways for technologies and people to intersect, because those strategies will have the best outcomes for the greatest number of people.”

The paper, “Multisectoral Emission Impacts of Electric Vehicle Transition in China and India,” was published October 25 in Environmental Science & Technology. In addition to Peng and Sharma, authors include Johannes Urpelainen of Johns Hopkins University, Hancheng Dai of Peking University, and Pallav Purohit and Fabian Wagner of the International Institute for Applied Systems Analysis (IIASA). The work was supported by the Wellcome Trust Climate Change and Health Award, as well as Princeton's School of Public and International Affairs.

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Journal

Environmental Science & Technology

DOI

10.1021/acs.est.4c02694 

Method of Research

Computational simulation/modeling

Subject of Research

Not applicable

Article Title

Multisectoral Emission Impacts of Electric Vehicle Transition in China and India

 

Threat of abrupt mortality events keeps endangered monkey population at risk, despite decades of growth

University of Wisconsin-Madison

 

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Karen Strier has been studying this population of northern muriquis for over 40 years.

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Credit: Photo by Joao Marcos Rosa

Despite the population being almost four times larger than it was in 1982, a new study published in the journal Ecology suggests the northern muriqui monkeys remain at risk, especially in the face of ongoing habitat disturbances.

Northern muriquis, which live in the Atlantic Forest of Brazil, are much more peaceful and egalitarian compared to other primates. They are also one of the most endangered species of monkey in the world.

Karen Strier, a professor of anthropology at UW–Madison and lead author of the paper, has spent 40 years studying the behavior and ecology of these monkeys in a small, preserved portion of Brazilian forest. She teamed up with Anthony Ives, a professor of ecology and evolution at UW–Madison, who is well versed in modeling demographic changes over time.

 “My goal is simply to put into statistics what Karen already knows,” Ives says. “She knows her data so well, and long-term studies with this level of detail for an endangered species are very rare.”

Strier and her team of Brazilian colleagues not only count the number of animals but also track their unique behavior, birth rates, death rates and relationships with one another. They know these animals as individuals, not just data points.

While the species and the land they live on is protected by Brazilian law, the muriquis’ mortality rate rose suddenly in 2016 and has not fallen since. Strier and Ives have found that the animals are still reproducing at a steady rate, pointing to other causes for the population decline.

“Our data imply that there may be some environmental stressors in the habitat such as a decline in forest productivity, which affects food availability, climate stress or predation causing the elevated mortality,” Strier explains.

The study also confirms the benefit of long-term, detailed studies such as this. By 2015, this population of muriquis had grown to a remarkable 356 animals, compared to the roughly 50 animals it consisted of when Strier had begun her data collection in 1982. Ives used data from the first 33 years of Strier’s study to create a model of what the population should look like over the next several decades under the conditions of 2015. It predicted the population would continue to rise exponentially until it reached a carrying capacity of about 500 animals, hovering around that size for the next few decades.

What that model couldn’t predict though, was the two years of drought that began in 2014 or the bout of yellow fever that swept through the population in 2016.

“If you just had data up to 2015, you’d say the population is great!” Ives explains. But luckily, Strier and her team continued to collect data beyond the drought and the yellow fever epidemic, making it possible to document the ongoing impact of habitat changes.

When Ives modeled the population changes, accounting for this dramatic decrease from 2016 to 2022, he found the population’s predicted carrying capacity to be only about 200 animals. And that’s assuming there won’t be another abrupt change to mortality like the one that started in 2016.

With predation and habitat change pinpointed as possible limiting factors for this muriqui population, conservationists are getting a clearer idea of where and how action may need to be taken.

“As almost all previous work from Karen, this will open a new window to understand and improve the design of our [conservation] strategies,” says Leandro Jerusalinsky, the head of the National Center for Research and Conservation of Brazilian Primates, part of the Ministry of Environment in Brazil.

Strier’s data can also be used alongside different models to predict how other populations of muriquis may react to changes in climate and future diseases. Those challenges grow increasingly more likely as climate models predict a warmer, drier world, resulting in increased environmental stress and food scarcity for muriquis and other primates.

Jerusalinsky hopes the data will help them understand what conditions these populations need to survive in the face of a changing world. Eventually it could inform conservation policies that might improve habitat quality management or create habitat corridors between isolated populations of the muriquis.

“Having a person like Karen developing this long-term research and providing these high-quality results is incredible,” Jerusalinsky says. “Even in the desperation we have facing this situation of (the muriquis), this gives us a lot of hope in effectively designing the best strategies possible to try to save this species.”

 

---Elise Mahon, etmahon@wisc.edu

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Journal

Ecology

Method of Research

Observational study

Subject of Research

Animals

 

University Hospitals is the first health system in northeast Ohio utilizing Da Vinci 5 Surgical Robot

Newest version provides technological advancements for both surgeons and patients

University Hospitals Cleveland Medical Center

 

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University Hospitals is the first health system in Northeast Ohio utilizing the Da Vinci 5 for robotic-assisted surgeries. With substantial improvements over previous models to provide a better experience for surgeons, caregivers and patients, this latest technology represents an evolution in robotic-assisted surgery.

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Credit: University Hospitals

University Hospitals is the first health system in Northeast Ohio utilizing the Da Vinci 5 for robotic-assisted surgeries. With substantial improvements over previous models to provide a better experience for surgeons, caregivers and patients, this latest technology represents an evolution in robotic-assisted surgery. Approximately 26 trained surgeons at UH Cleveland Medical Center will be using this robot for a large variety of cases, including esophagectomies and gastric bypasses.

“The adoption of the DV5 is not just about technology – it reflects UH’s strategic investment in the future of robotics,” explained thoracic surgeon Christopher Towe, MD, the Charles A. Hubay, MD, Chair in Surgery, who performed the first case with the DV5 in November. “This aligns seamlessly with our mission to heal, to teach and to discover, reinforcing our dedication to providing the highest-quality care for our patients while staying at the forefront of medical innovation. By integrating systems like the DV5, we are ensuring that UH remains a leader in both patient outcomes and surgical education.”

The first case was a hiatal hernia repair, and the second case was a resection of a mass in the thymus glad. Both procedures were successful and the patients were able to go home within a day due to the minimally invasive aspect of the DV5.

The DV5’s improvements resulted from a decade of research and more than 14 million procedures performed on earlier models of the da Vinci robot, of which UH Cleveland Medical Center has six. UH currently has eight additional models of da Vinci robots throughout the health system at community hospital locations across Northeast Ohio, with another expected to be added soon.

Benefits of the new DV5 robot include:

• Telepresence – Allows live-streaming of surgical procedures in real-time, enabling education, training, and collaboration with colleagues across the globe.
• Compact design – A smaller footprint so it can be used in various types of operating rooms, even those not originally designed for robotics.
• Enhancements in controls – Improved visualization and haptic feedback, a technology that simulates touch, for more precise minimally invasive procedures.
• Improved ergonomics – A redesigned surgeon console offers customizable positioning to accommodate a wide range of body types and provide more comfort during lengthy procedures.

The new technology benefits more than just surgeons in the operating room. From a nursing perspective, the compact tower of the DV5 also reduces the amount of movement around the room for the circulating nurse. This robot integrates multiple functions, including integrated laparoscopic equipment, into one tower rather than multiple units in the room, taking up less space and enhancing efficiency. Circulators can control the energy for cautery that helps with hemostasis during cases, as well as insufflation -- gas needed to expand the operative space during procedures. 

“This console is more ergonomically satisfying for the surgeons, and the tower enhances efficiency for the circulators,” said UH Cleveland Medical Center Robot Coordinator, Larisa Rebello, RN, BSN. “We can change those settings immediately for the surgeons, and the surgeon can adjust settings easily on their own. It’s the small, but critical, details that make operating a better experience for all. We’re excited to have this new technology and be the first in Northeast Ohio.”

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About University Hospitals / Cleveland, Ohio
Founded in 1866, University Hospitals serves the needs of patients through an integrated network of more than 20 hospitals (including five joint ventures), more than 50 health centers and outpatient facilities, and over 200 physician offices in 16 counties throughout northern Ohio. The system’s flagship quaternary care, academic medical center, University Hospitals Cleveland Medical Center, is affiliated with Case Western Reserve University School of Medicine, Northeast Ohio Medical University, Oxford University, Taiwan National University College of Medicine and the Technion Israel Institute of Technology. The main campus also includes the UH Rainbow Babies & Children's Hospital, ranked among the top children’s hospitals in the nation; UH MacDonald Women's Hospital, Ohio's only hospital for women; and UH Seidman Cancer Center, part of the NCI-designated Case Comprehensive Cancer Center. UH is home to some of the most prestigious clinical and research programs in the nation, with more than 3,000 active clinical trials and research studies underway. UH Cleveland Medical Center is perennially among the highest performers in national ranking surveys, including “America’s Best Hospitals” from U.S. News & World Report. UH is also home to 19 Clinical Care Delivery and Research Institutes. UH is one of the largest employers in Northeast Ohio with more than 30,000 employees. Follow UH on LinkedIn, Facebook and Twitter. For more information, visit UHhospitals.org.

 

New study finds marine animals save energy by swimming in a depth ‘sweet spot’

Swansea University

 

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Like many air-breathing marine megafauna, green turtles optimise their swim depth during migration to minimise the cost of transport, travelling at around three body-depths beneath the surface in order to avoid creating waves whilst maximising horizontal distance travelled. 

 

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Credit: Credit: R. D. and B. S. Kirkby.

R,esearchers from Swansea and Deakin Universities have found that marine animals across mammals, birds and reptiles swim at similar relative depths when travelling and not feeding to save energy.

Dr Kimberley Stokes, Professor Graeme Hays and Dr Nicole Esteban from Swansea and Deakin Universities, led research across six institutes in five countries comparing the swim depths of several sea turtle, penguin and whale species. All travelled at around three body depths from the surface in order to swim in the 'sweet spot' that minimises wave formation at the surface and vertical distance travelled.

Some semi-aquatic animals, such as mink, swim at the surface where wave generation is a major source of wasted energy. However for marine birds, mammals and reptiles travelling great distances over their lifetimes, adaptation to minimise the energetic cost of transport is expected, particularly on long journeys.

It has long been known that additional drag from wave creation minimises once a travelling object is at depths greater than three times its diameter, but it was hard to compare with travel depths of wild animals due to tracking limitations.

In this new study published in Proceedings of the National Academy of Sciences (PNAS) near surface swim depths were recorded to within 1.5 centimetres in little penguin and loggerhead turtles, along with motion data and video footage from animal borne cameras. This was compared with satellite tracking data for long-distance migrations in green turtles and data from other studies on penguins and whales. It was found that these animal swim at optimal depths predicted from physics when either 'commuting' to a foraging patch in the wild or migrating over longer distances while not feeding. 

Swansea University’s Dr Kimberley Stokes, lead author of the study said:

“There are of course examples where animal swim depth is driven by other factors, such as searching for prey, but it was exciting to find that all published examples of non-foraging air-breathing marine animals followed the predicted pattern. This has rarely been recorded because of the difficulty in retrieving depth data from animals that migrate over large distances, so it was great to find enough examples to show a common relationship between swim depth and body size from animals across the size spectrum from 30 cm to about 20 m in length.”

Little penguins travel beneath the zone of highest wave drag close to the surface. Many air-breathing marine vertebrates optimise their swim depth when transiting and not feeding, travelling just deep enough to avoid wave creation on the surface. 

 

Credit

Phillip Island Nature Parks.

Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2413768121 

Subject of Research

Animals

Article Title

Optimization of swim depth across diverse taxa during horizontal travel

Article Publication Date

16-Dec-2024

 

Corals depend on near neighbours to reproduce

University of Queensland

 

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Coral spawning in Palau.

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Credit: Peter Mumby

A new study reveals corals must be within only a few metres of each other to successfully reproduce, leaving them vulnerable in a warming world.

The international research, led by The University of Queensland’s Professor Peter Mumby, measured the success of a natural spawning event in March this year.

“In what came as a surprise, we saw that corals needed to be within 10 metres of one another, and preferably closer than that for fertilisation to take place,” Professor Mumby said.

“We knew corals couldn’t be too far apart, but we found they need to be closer than we’d expected.

“Climate change impacts like bleaching are killing and reducing the density of corals, so we’re concerned that individuals may end up too far apart to reproduce successfully.”

To quantify reproduction success, the team placed containers above 26 coral colonies on a reef in Palau, Micronesia during a time when the mostly hermaphroditic corals released eggs and sperm.

“The containers captured some of each corals’ eggs and drifted to the surface where they followed the tide,” Professor Mumby said.

“Although the eggs could not escape, sperm could enter the container and fertilise the eggs.

“After an hour of drifting, the proportion of fertilised eggs was noted for each type of coral along with the distance to similar established corals.”

Fertilisation averaged 30% when corals were very close, but it declined to less than 10% at a separation of 10 metres and was virtually zero by 20 metres.

Co-author Dr Christopher Doropoulos of the CSIRO, Australia’s national science agency, said coral reproduction was fundamental to population resilience and evolution.

“In the future we may need to help corals continue this key part of their lives,” Dr Doropoulos said.

“Understanding the importance of local neighbourhoods provides tangible targets for interventions like coral restoration.

“Ideally, the density of corals would be monitored at important locations and restoration carried out to return the density back to the levels required for successful reproduction.”

Professor Mumby has been working on efforts to repair damaged coral reefs.

“Our work over the past 5 years on the Great Barrier Reef through the Reef Restoration and Adaptation Program is also helping to define these critical thresholds to help restoration practitioners set targets for density to help maintain coral populations,” he said.

The study was funded by the McCusker Foundation and the Australian Government’s Reef Restoration & Adaptation Program.

The research is published in the Proceedings of the National Academy of Sciences USA (PNAS).

Images and video available via Dropbox.

Reef research site in Palau.

Credit

Peter Mumby

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Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2418314121 

Landmark study using 21 years of New England Aquarium’s Marine Conservation Action Fund (MCAF) data finds small grants advance ocean conservation and equity

Perspective piece in the journal Biological Conservation examines how small grants to local projects worldwide yield success in advancing global ocean conservation and equity

New England Aquarium

A recently-published study in the journal Biological Conservation highlights how small grants can address ocean conservation challenges in a manner that promotes social equity.

Low- and middle-income countries (LMICs) are disproportionately impacted by threats to ocean health, such as overfishing and climate change, which are often caused by the world’s high-income countries (HICs). These inequities and resultant challenges affecting both marine biodiversity and livelihoods in LMICs have been driven by a long history of resource extraction and colonialism by HICs. The study authors point to characteristics of grant programs that make them accessible for local leaders, who are best positioned to design conservation action in their communities.

This perspective piece was authored by marine conservationists working with the New England Aquarium’s Marine Conservation Action Fund (MCAF), which is celebrating 25 years of supporting locally based conservation projects and leaders worldwide. Among the paper’s authors are MCAF Director Elizabeth Stephenson and Program Manager Emily Duwan, as well as MCAF fellows and collaborators who have helped shape the program. As a case study for small grants, Stephenson and her colleagues analyzed project characteristics and outcomes from MCAF’s grantmaking over two decades, from 1999-2020. Projects supported by MCAF had immediate impacts, like filling knowledge gaps, protecting individual animals, and strengthening marine protected areas (MPAs). They also contributed to lasting conservation impacts, including new species protections, creating new MPAs, and sustained research and monitoring efforts.

“Historical inequities and current threats to ocean health make flexible grant-making a priority. It is more critical than ever to promote local leadership and ensure that conservationists on the frontlines have funding to develop the solutions they know are needed,” says Stephenson.

In its second decade, MCAF shifted to funding more projects led by individuals working in their own LMICs. This shift helps to combat the problem of “parachute science”—a practice whereby scientists from HICs work in LMICs without meaningful collaboration with local experts. This practice perpetuates inequities in LMICs and is a barrier to creating lasting, locally informed solutions. The authors highlight how grants programs can promote equity in conversation by providing accessible and flexible funding and leaving project design in the hands of local LMIC leaders. 

“This analysis, which showcases the evolution of the MCAF program, highlights how supporting locally led conservation efforts can shift the needle on driving change for our oceans,” said co-author and longtime MCAF Fellow Dr. Asha de Vos of Oceanswell in Sri Lanka and The Oceans Institute in Australia. “Funding local leaders ensures that those on the ground, at the forefront of these conservation issues who often work with shoestring budgets year after year, are recognized, supported, and given a seat at the table. It creates a sense of custodianship and inspires future leaders to emerge from these communities. In the end, to save the world's largest ecosystem, we need to build the world's largest team.”

Among the authors’ recommended strategies for grant programs to amplify their impact and promote equitable practices are to:

•    Support established and emerging leaders from LMICs,
•    Make long-term investments in project leaders and organizations by offering multi-year, unrestricted funding and grants,
•    Provide multi-faceted support for project leaders so they can elevate the visibility of their projects,
•    And regularly seek feedback and guidance from project leaders on program strategy and funding decisions.

Joining current MCAF staff as co-authors are former MCAF Coordinator Bess-Lyn Edwards; MCAF fellows Dr. Asha de Vos of Oceanswell in Sri Lanka and The Oceans Institute in Australia, Kerstin Forsberg of Planeta Océano in Peru and Migramar of California, and Dr. Nelly Isigi Kadagi of World Wildlife Fund; Benny Berger and Dr. Michael Tlusty of University of Massachusetts Boston; and Dr. Jessica V. Redfern, Associate Vice President in the Aquarium’s Anderson Cabot Center for Ocean Life’s Ocean Conservation Science.
 

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Journal

Biological Conservation

DOI

10.1016/j.biocon.2024.110845 

Method of Research

Case study

Subject of Research

People

Article Title

Small grants advance global ocean conservation and management equity

Article Publication Date

14-Nov-2024

COI Statement

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Elizabeth H. Stephenson, Emily Duwan, Bess-Lynn Edwards, and Benny Berger report a relationship with the New England Aquarium's Marine Conservation Action Fund that includes: employment. Nelly Isigi Kadagi, Asha de Vos, and Kerstin Forsberg report a relationship with the New England Aquarium's Marine Conservation Action Fund that includes: funding grants. Nelly Isigi Kadagi, Kerstin Forsberg, and Michael F. Tlusty serve on the New England Aquarium's Marine Conservation Action Fund advisory committee.

New findings on the North Atlantic Oscillation displacement

Why does the NAO move longitudinally?

University of Barcelona

 

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A study led by a team from the University of Barcelona is helping to resolve some enigmas about the causes of the displacements in the North Atlantic Oscillation (NAO), one of the most influential patterns of variability in the climate of the Northern Hemisphere.

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Credit: Npj Climate and Atmospheric Science

There are still many unknowns about the causes leading to the North Atlantic Oscillation (NAO) shift — a critical climate phenomenon in the Northern Hemisphere — to the east and west of Iceland. To date, some hypotheses suggested that this process known to the international scientific community might be related to the impact of greenhouse gases on the planet.

Now, a study published in the journal Npj Climate and Atmospheric Science reveals that the NAO shift may be a consequence of natural variability in the atmospheric system rather than anthropogenic effects altering global climatology. The new study is led by experts María Santolaria-Otín and Javier García-Serrano, from the Faculty of Physics and the Group of Meteorology at the University of Barcelona.

Why does the NAO move longitudinally?

The North Atlantic Oscillation was first identified in the early 20th century, although its consequences were known to the people of northern Europe much earlier. The NAO is one of the most studied climate variability phenomena in the scientific community. However, many aspects of the dynamics and processes controlling its variability, both temporally and spatially, are still unknown, and the evidence for its past and expected future trends is still being debated.

Javier García-Serrano, professor at the UB’s Department of Applied Physics, says that “the atmosphere is a fluid system and shows a very chaotic and unpredictable behaviour. The study reveals that we can rule out some factors that explain this NAO pattern, namely anthropogenic forcing — i.e. the impact of greenhouse gases — or ocean coupling. Factors that could help to understand these shifts in the NAO are, for example, the interaction of winds with orography or the land-sea contrast. However, we need more research studies to confirm these hypotheses”.
​​​​​​​
On a global scale, the effects of this NAO shift are likely to be small, although they could affect Arctic Sea ice variability and, consequently, other remote areas of the planet. According to the findings, this process would not alter anthropogenic global warming trends.

Regional scale effects would be more important, since the NAO explains about half of the climate variability in the area of the European continent and the Mediterranean. “However, its impact on future predictions and projections would mainly be to modulate climate change trends in certain periods”, says García-Serrano.

In this context, the UB team has carried out and analysed simulations over a period of 500 years with a global climate model. María Santolaria-Otín, postdoctoral researcher and first author of the study, notes that “by applying this innovative methodology, it has been possible to isolate the effects of radiative forcing and ocean coupling and thus obtain conclusions that are impossible to reach with observational data alone”.
​​​​​​​
The NAO is considered one of the most influential patterns of low-frequency variability (teleconnections) in the climate of the Northern Hemisphere. In this challenging scenario, the UB team continues to expand their studies to understand what factors control NAO shifts and their remote effects in the context of global

 

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Journal

npj Climate and Atmospheric Science

DOI

10.1038/s41612-024-00842-8 

Method of Research

Observational study

Subject of Research

Not applicable

Article Title

Internal variability of the winter North Atlantic Oscillation longitudinal displacements