If you look at a wheat field, it is easy to imagine that not much is happening. The plants stand quietly in the soil. They grow, turn green, produce grain and wait for harvest. But underneath the surface, it is a completely different story.

The roots are surrounded by millions of microorganisms. Some of these tiny organisms can help plants access nutrients, while others may help them cope with difficult conditions.

And the plant is not simply sitting there passively. Its roots release substances that influence the microorganisms living around them. So, in a way, the plant and the microorganisms may be talking to each other. But what does that even mean? 

That is the starting point for a new European research project called EVOLVE, led by Associate Professor Ivan Paponov from Aarhus Universitys Department of Food Science (AU FOOD) and his team of researchers.

Together, they want to understand this interaction and find out whether it could eventually help wheat use nutrients more efficiently and cope better with drought and other environmental stresses.

Tiny packages carrying messages

Plants release many different substances through their roots. EVOLVE is particularly interested in one possible way that plants send biological signals: tiny particles called extracellular vesicles.

The name sounds complicated. But the basic idea is easier to understand: Think of them as small packages, Ivan explains. They are enclosed by a membrane and can carry biological molecules such as small RNAs. The researchers will investigate whether small RNAs carried by these vesicles can influence specific microorganisms around the roots and whether those microorganisms respond in ways that benefit the plant. 

These are some of the questions Ivan and his team will explore in EVOLVE.

It started with a simple question

The idea behind EVOLVE did not begin as a grand research plan. It started with a question.

Ivan was already studying substances released from plant roots. He was also interested in the small vesicles involved in transporting biological material within plant cells. Then the two areas of research came together in his mind, and produced a question: Could some of the substances released by roots be packaged into these tiny vesicles and transported out of the roots?

It sounded a little unusual at first, but that was also what made it so interesting, Ivan says.

He discussed the idea with a colleague who was studying extracellular vesicles in pollen. The response was simple: Why not investigate it?

That conversation eventually grew into a larger collaboration. Step by step, more researchers joined, the idea developed and the project was ultimately selected for funding by the European Union.

Today, eight organizations in seven countries are working together on EVOLVE for the next three years. 

What if we could breed plants that are better at teamwork?

This is where the idea could become particularly interesting for agriculture.

Plant breeders normally select plants for characteristics such as high yield, good quality or the ability to cope with drought and other stresses. But what if breeders could also look at how a plant interacts with the microorganisms around its roots?

Different wheat genotypes may produce different biological signals. Some plants might be better than others at influencing microorganisms in ways that improve nutrient use or help the plant cope with stress.

EVOLVE will investigate whether such differences exist and whether they could eventually be useful in plant breeding. Instead of selecting a plant only for what it can do on its own, breeders might one day also be able to consider how well it interacts with the microorganisms around its roots.

For us, this opens up an exciting new opportunity for plant breeding, says Ivan. But first, the researchers need to establish whether the idea works.

Could microorganisms help wheat use less fertilizer?

One of the big questions in EVOLVE is nitrogen. Wheat needs nitrogen to grow, and farmers currently supply much of it through fertilizer. But plants do not take up all the nitrogen that is added to the soil. Some is lost to the environment.

But what if microorganisms could help wheat access more of the nutrients that are already available?

Some microorganisms around plant roots can contribute to nutrient availability. EVOLVE will investigate whether wheat can influence these microorganisms and whether extracellular vesicles and the biological molecules they carry play a role.

If the researchers can understand and eventually make use of these interactions, it could help develop crops that use nutrients more efficiently.

The project is also investigating algae-based biofertilizers. The idea is not simply to add nutrients to the soil. The researchers will explore whether algae could provide extracellular vesicles and other biological signals that influence microorganisms around plant roots.

In other words, could a biofertilizer do more than feed the plant? Could it also help influence the microscopic community around the roots? That is something the researchers will have to test.

And what about drought?

The researchers are also interested in what happens when water becomes scarce.

Some microorganisms around plant roots are known to help plants cope with drought. EVOLVE will investigate whether extracellular vesicles released by wheat, and the biological molecules they carry, can influence these beneficial microorganisms.

If the researchers find that they can, this could point towards a new way of helping plants make better use of their natural relationships with microorganisms when conditions become stressful.

In the longer term, the researchers hope this knowledge could contribute to identifying wheat plants that maintain yield and quality better under difficult conditions. But there is a long way to go before that becomes an agricultural technology.

From an intriguing idea to scientific evidence

EVOLVE is exploring a relatively new area of research, and the researchers do not yet know whether the mechanism they are investigating will work in the way they hope.

First, they need to understand what signals the plants produce, how those signals work and which microorganisms respond to them. They also need to find out whether different wheat genotypes differ enough for these interactions to become useful in plant breeding.

The project will begin with 48 different wheat genotypes. The researchers will investigate whether their methods can eventually be scaled up to much larger numbers of plants. Artificial intelligence will also be part of the project, helping the researchers analyze large amounts of biological data and look for patterns. 

The aim is not to assume that the idea works, but to find out whether it works, how it works and whether it could eventually be useful.

Many years of research come together

For Ivan, EVOLVE also brings together many different strands of his scientific career.

Over the years, he has worked on plant breeding, plant nutrition, nitrogen use, molecular biology and bioinformatics. He has also studied the tiny vesicles involved in transport within plant cells and the substances plants release into their surroundings. Now, these different areas are coming together in one project.

In a way, it feels like many years of research are coming together here, he says.

Over the next three years, Ivan and his international team will try to work out what is really happening beneath the wheat field. Are plants sending biological messages? Are microorganisms responding? And, perhaps most importantly, can we help wheat make better use of these relationships?

The answers are not known yet. But if the researchers can demonstrate that these interactions work as they suspect, it could give plant breeders a new tool and potentially offer a new way of thinking about sustainable agriculture. If successful, EVOLVE could open a new approach to crop improvement: looking not only at the plant itself, but also at how effectively it interacts with the microorganisms around its roots.

Some cardiovascular diseases occur almost exclusively in women. Others present with different symptoms, develop differently or are associated with different risk factors.

This is no coincidence. Part of the explanation is that women have historically been underrepresented in cardiovascular research. But according to Monika Colombo, Associate Professor at Aarhus University, that is only half the story.

"Fortunately, we have become much better at including women in clinical research. But we are still not very good at incorporating the biology that makes women and men different into the models we use to understand cardiovascular disease. That is the fundamental knowledge we are still missing," she says.

Colombo now hopes to address that challenge through DISSEX, a research project awarded a prestigeous 1.5 million ERC Starting Grant under the European Union's Horizon Europe programme.

The project will investigate how hormones, stress and genetic factors influence women's coronary arteries and develop new models to explain why certain cardiovascular diseases affect women differently from men.

Why does an artery suddenly become vulnerable?

Researchers already understand a great deal about how blood flows through the coronary arteries and the mechanical forces acting on the vessel wall.

What they understand far less well is how the body's own biological signals influence the cells that make up those blood vessels.

How do hormonal changes affect the strength of an artery throughout life? What role does physical and psychological stress play? And how do genetic factors interact with the mechanical forces that arteries experience every second of every day?

Current scientific models can only partly answer those questions.

Through DISSEX, Colombo's team will bridge biology and biomechanics. By combining laboratory experiments, advanced medical imaging and computational modelling, the researchers will investigate how biological signals gradually alter the properties of blood vesselsand how those changes may eventually make an artery vulnerable to rupture.

"Today we can measure hormones and we can study the shape of blood vessels. What we still lack is an understanding of how the body's biology changes the cells within the vessel wall over time. That is the missing connection we are trying to uncover," says Colombo.

A disease that exposes a wider knowledge gap

The project focuses on Spontaneous Coronary Artery Dissection (SCAD), a condition in which a spontaneous tear develops within the wall of a coronary artery.

SCAD predominantly affects women, many of whom have none of the traditional risk factors associated with cardiovascular disease.

Simon Winter sees these patients in his clinical work. He is a consultant cardiologist at the Department of Cardiology at Gødstrup Regional Hospital and a clinical professor at Aarhus University, and serves as an advisor to the project.

"We see younger women coming in with what initially looks like a heart attack, but the underlying cause is not the usual build-up of plaque in the arteries. Instead, a tear develops in the artery wall, which can obstruct the flow of blood. It is a serious condition that can strike relatively early in life, and it can also take a considerable psychological toll on patients," he says.

This is precisely why SCAD challenges our current understanding of cardiovascular disease.

If clinicians are to become better at identifying who is at risk, understanding the mechanics of blood vessels alone is not enough. They also need to understand how hormones, stress and genetic factors shape the biology of the artery wall throughout a person's life.

To achieve this, the researchers will study living human coronary artery tissue and combine those findings with patient data and advanced computational models. Their goal is to uncover the biological mechanisms that gradually make an artery more susceptible to dissection.

"This is an area where we still lack fundamental knowledge. We need to understand why the condition occurs. Are some artery walls particularly vulnerable? Do hormones play a role? Or is it the result of several factors interacting? If we can identify markers and gain a better understanding of how the disease develops, we may also become better at knowing what to look out for in our patients," says Simon Winter.

From fundamental biology to more precise cardiovascular medicine

In the longer term, the researchers aim to develop personalised rupture-risk maps of the coronary arteries.

By integrating knowledge about hormones, genetics and biomechanics, they hope to identify patients at increased risk earlier and provide clinicians with better tools for diagnosis, monitoring and treatment planning.

For Colombo, however, the project's significance extends well beyond a single disease.

She hopes DISSEX will help reshape how researchers investigate women's cardiovascular health more broadly.

"If we want precision medicine, we also need models that reflect the biological diversity of patients. Women's cardiovascular physiology should not simply be regarded as a variation of a male standard. It deserves to be understood on its own biological terms," she says.

Aarhus University is home to several major initiatives focusing on womens health. Here are five examples:

• The research project Womens Health and Well-being is conducting Denmarks largest-ever study of womens health and well-being, including a survey of 300,000 women.
• PREG-AID investigates how medicines used to treat autoimmune diseases affect both mother and child during pregnancy.
• The FEMaLe project uses artificial intelligence and health data to improve the detection and treatment of endometriosis. The project has helped raise awareness of the disease in both Denmark and the EU.
• The BIOSFER project investigates the reasons behind declining fertility and explores how biological, social and psychological factors contribute.
• The Womens Health Network brings together researchers and other stakeholders to strengthen research into womens health..

Contact

Associate Professor Monika Colombo
Department of Mechnical and Production Engineering, Aarhus Universitey
Mail: mc@mpe.au.dk
Tel: +4522189869

Jesper Bruun
Journalist, Aarhus University
Mail: bruun@au.dk
Tel.: +4542404140

I remember how incredibly nerve-racking it was to read the first newspaper article I appeared in 16 or 17 years ago. What if I had said something wrong? You think its set in stone and will be there for ever, but eventually you realise that its forgotten the next day. Fortunately, my head of research at the time, Hans Lykke, took me under his wing and taught me how to handle it: stick to my area of expertise and be very clear about what I know and what I dont know. I know nothing, for example, about the feelings of killer slugs. That isnt my field of research, so Ill leave that to others, says Stine Slotsbo from her garden in the village of Elev.

Know your enemy

It was her interest in ectothermic animals that originally led her to write her masters thesis on freeze tolerance in earthworms. Then, in 2008, while working as a research assistant at the National Envi-ronmental Research Institute of Denmark, she was given the opportunity to pursue a PhD on the biology of killer slugs and the effects of climate on them. This marked the beginning of a years-long battle in the laboratory to understand the enemy and, in doing so, find an effective way of controlling it. Knowledge that many gardeners would probably kill for. More on that later. In September 2026, Stine Slotsbo will receive the Else Kai Sass Award, named after the first female professor at Aarhus University. The award is presented to a candidate who brings knowledge from AU into wider
society and who has made a particularly positive contribution to research communication, collaboration and innovation.

Im very grateful, but at the same time I have slightly mixed feelings about awards. After all, this has been a joint effort involving a great many of my colleagues, and I could never have done it alone, she says.

Two queens meet

Although Stine Slotsbo has become something of Denmarks queen of killer slugs, there is still room for other research projects. Together with a wide range of collaborators, she has secured two major grants to investigate the potential for producing sustainable fish feed. The aim is to reduce fish producers dependence on conventional marine-based feed, including small crustaceans, and replace it with something as simple as worms. In a way, this takes us back to the beginning of Stine Slotsbos research career and her freeze-resistant earthworms. During the project, she and her colleagues discovered that the worms can themselves produce omega-3 fatty acids, which are important for fish growth and health. This means fish feed no longer needs to be enriched with fish oil, potentially simplifying production while making it more climate- and environmentally friendly. Full circle for both fish and researcher.

Its great fun when you actually manage to create a consortium where people genuinely work together and those competitive dynamics arent there. People are open, and the project itself is what matters, says Stine Slotsbo, referring to collaborators including the Technical University of Denmark (DTU), Aalborg University and several companies.

As project leader, she even had the opportunity to present the idea of sustainable fish feed to a real queen when Queen Margrethe visited Aarhus Universitys University City campus in 2023. Stine Slotsbo was given three minutes in a room with Rector Brian Bech Nielsen, The Kitchens Director of Enterprise Lone Ryg Olsen, and Margrethe II accompanied by her lady-in-waiting. It was a small, exclusive performance that in several ways reminded her of Forsker Fight many years earlier, when she won an internal competition to explain her PhD project in just four minutes.

Its a great constraint, because if youre well prepared, you can say an incredible amount in three or four minutes. Even though meeting the Queen like that was a unique experience, what I was really thinking about was making sure everyone could understand what I was saying. And thats always the case when I communicate my research. The only difference here was that I had to remember to address her formally rather than informally, says Stine Slotsbo, before we have to interrupt the interview for a while and head indoors to escape the rain. Darwin barks, and the killer slugs rejoice. Because surely they have feelings?

The price of communication

There is another question that demands an answer. How much can you simplify your research before you begin to compromise its academic rigour? It is a dilemma Stine Slotsbo recognises:

In the past, it was almost considered cheating if a researcher communicated something in everyday language, because if you didnt use all the sophisticated terminology, you somehow werent as clever. Its not that our specialist terminology is unnecessary its actually really useful when Im talking to fellow researchers. I can use exactly the right technical term without having to explain a whole host of things. But when youre speaking to the general public, the jargon has to go, because no one becomes any wiser if people dont understand half of what youre saying. Fortunately, I find that young researchers have a slightly different approach to science communication from my own generation. They think its fun.

The two killer slugs have now made their way indoors as well, sitting on the living-room table in a plastic container, and they appear capable of coping with all kinds of weather. At the beginning of her PhD project, Stine Slotsbo had a theory that the killer slug was not freeze-tolerant, and that this could provide the key to killing it. But the only thing that died was the idea. Since then, she has devoted a large part of her career to understanding the animal and helping the rest of us understand it too.

The cold, hard fact is that the killer slug is here to stay. 

But this years The Climate Festival will also examine the smaller dilemmas of everyday life: Should we fly or take the train, eat less meat, buy new products or repair what we already have and how much responsibility really lies with the individual?

For Jørgen E. Olesen, Head of the Department of Agroecology, this is precisely where AUs research needs to demonstrate its potential and bring new perspectives to the table:

Looking at the bigger picture, we will only succeed in tackling the climate challenge if we combine new green technologies with changes to our lifestyles. This requires connecting the local with the global. We need to mobilise all our resources if we are to succeed, and at AU we are contributing across the board, he says.

The good life

Since 2017, The Climate Festival in Middelfart has developed from a local event into a national gathering where researchers present the latest knowledge, companies showcase practical solutions, and visitors can see, hear, touch and taste for themselves how climate issues affect both the big picture and the small details of everyday life. Last year, around 40.000 people attended.

Once again this year, Aarhus University researchers will contribute to the programme from iClimate, the Department of Agroecology, the Department of Animal and Veterinary Sciences, the Department of Environmental Science and the Department of Civil and Architectural Engineering, together with a number of interdisciplinary research environments and partners.

Søren Wandahl, Head of the Department of Civil and Architectural Engineering, sees The Climate Festival as a unique opportunity to engage in dialogue about how we can significantly reduce the climate and resource footprint of the construction sector while continuing to support good homes, strong communities and a high quality of life:

At the Aarhus Centre for Regenerative Building, one of the things we are investigating is what it will take to promote a new paradigm for construction in which we plan, design, build and live within planetary boundaries. This requires interdisciplinary collaboration, new knowledge and dialogue across disciplines. At The Climate Festival, we encounter a wide range of stakeholders and disciplines that bring new ideas, perspectives and partnerships, all of which can help shape the built environment of the future, he says.

Hay fever and the Greenland ice sheet

Visitors will also be able to test their knowledge of the Greenland ice sheet as researchers explore what is true and false about the climate of the future. They can learn more about how microorganisms in the soil could help make crops more resistant to drought. And they can find out why Denmarks Green Tripartite agreement could inadvertently result in more Danes suffering from hay fever.

War, security and geopolitical unrest have taken up an increasing share of political attention in recent years. But climate change has not become any less urgent which is precisely why it remains important to bring research-based knowledge into the public debate, says Jørgen E. Olesen:

Climate change is not something that belongs to the future. It is already here and, in many areas, its consequences are far more serious than we predicted a couple of decades ago. Rising food prices and increased algal growth in the sea are just two examples. We need to take these impacts into account in public and private planning to a far greater extent than we do today.

Find the full programme for The Climate Festival here. 

Contact:

Jonathan Torp Henschel
Jth@agro.au.dk
+45 41 89 32 41

Gitte Brandt Hedegaard
gbh@envs.au.dk
+45 21 61 25 77

Blue mussels feed by filtering microscopic algae from seawater. But some unwelcome guests can slip in along with their food. Tiny parasite larvae can hitch a ride as the mussel pumps water in and out.

New research from Aarhus University shows that blue mussels have a defence. When they detect the risk posed by certain parasites, they simply reduce their filtration. And when things get particularly risky, they can even close their shells completely.

This leaves the mussel with something of a dilemma: if it stops filtering, it stops eating. But there is more at stake than the mussels own dinner. A single large blue mussel can filter up to 100 litres of seawater a day, and millions of mussels can congregate in large beds.

Here, they act as ecosystem engineers. By filtering microalgae from the water, mussels affect water clarity and nutrient cycling. The beds themselves also form a landscape of shells, gaps and crevices that provide habitats for small animals, fish and plants. So when fear of parasites causes mussels to cut back on one of their most important activities, the effects could potentially be felt on a much larger scale.

That is what makes this response so interesting. We are looking at something that happens in an individual mussel, but because blue mussels play such an important role in coastal ecosystems, even small changes in their behaviour could potentially matter on a much larger scale, says PhD student Pernille Kibak, one of the researchers behind the study, which has just been published in the scientific journal Journal of Helminthology.

Fear changes mussel behaviour

The researchers explored the phenomenon in a series of laboratory experiments in which they exposed blue mussels to larvae from three different species of parasitic flatworm.

Two of the species can infect blue mussels, while the third infects fish and therefore does not pose the same threat. The clearest response occurred with the parasite Himasthla elongata. In its presence, the mussels reduced their filtration activity by 34 per cent. When the researchers combined H. elongata with another mussel parasite, Renicola roscovita, filtration fell by 51 per cent compared with the control group.

The researchers also found a clear link between filtration activity and the parasites success. The more actively a mussel filtered, the more parasites were subsequently found inside it. By reducing filtration, the mussel can therefore make it harder for parasites to get in.

But what is particularly interesting is that the mussel responds to the risk before the parasite has had a chance to cause harm. It changes its behaviour simply because of the prospect of infection. That is exactly the mechanism we are talking about when we use the term ecology of fear, says Pernille Kibak.

The concept originally comes from research into predators and prey. Predators do not shape their surroundings only by eating other animals. The mere risk of becoming someone elses dinner can cause prey to change their behaviour, move to different areas, or spend more time keeping watch and less time feeding.

Researchers have since extended the idea to parasites. Although a parasite does not necessarily kill its host in the same way a predator kills its prey, infection can impair growth, survival and reproduction. Detecting danger early can therefore pay off.

The researchers also wanted to find out whether blue mussels can actually distinguish between parasites that can infect them and those that cannot. Here, the results were less clear-cut. The mussels responded differently to the three species, but variation between individual mussels was too great for the researchers to conclude that blue mussels can distinguish between the different parasite species.

Something in the water

The next experiment brought a surprise.

The researchers removed the parasites themselves and instead exposed the blue mussels to water containing chemical cues from common periwinkles. The snails pose no threat to blue mussels in themselves. But they play an important role in the parasites life cycles, because several of the parasites that later infect blue mussels first live and reproduce inside the snails.

The mussels nevertheless responded strongly. Chemical cues from the periwinkles alone caused their filtration activity to fall by almost 42 per cent compared with the control group.

That was one of the things that surprised us most. The snail itself does not harm the mussel, but its presence can be a sign that parasites are nearby. It may almost work like a warning sign in the water: there is reason to be on your guard, explains Pernille Kibak.

Blue mussels have a well-developed sensory system capable of detecting chemicals dissolved in the surrounding water. Food, predators, injured members of their own species and parasites can all alter the chemical composition of the water around them, providing signals to which the mussels can respond.

The researchers do not yet know exactly which signal causes the blue mussels to reduce their filtration. Water containing chemical cues from both parasites and infected snails did not cause significantly lower filtration than water containing cues from the snails alone. The results therefore suggest that cues from the periwinkle play an important role, but the precise chemical mechanism remains unknown.

That makes the finding all the more intriguing. A blue mussel spends most of its life anchored in place by strong byssal threads. It cannot simply flee when parasites appear. Instead, it has to respond to the information drifting past in the water.

When an entire mussel bed clams up

This creates a larger paradox: a response that may protect an individual mussel from parasites could potentially have consequences for the surrounding ecosystem if many mussels respond in the same way.

Mussel filtration helps move organic matter from the water towards the seabed and contributes to nutrient cycling in coastal ecosystems. The researchers therefore point out that reduced filtration could potentially affect the deposition of organic matter, nutrient cycling and the flow of energy through these ecosystems.

But there is a considerable leap from one mussel in a laboratory experiment to millions living in a natural mussel bed. Parasite abundance and environmental conditions vary in the wild, and mussels may be able to compensate for periods of reduced filtration by filtering more at other times.

The laboratory experiments show some really interesting trends, but we cannot simply transfer them directly to a natural mussel bed. That is why it would be really interesting to study filtration activity in the field and see whether we find the same pattern under natural conditions, says Pernille Kibak.

The question may become even more pressing as the oceans warm. Parasites pass through several life stages that are strongly dependent on temperature. Climate change could therefore alter both where parasites occur and when they are present in the water. At the same time, temperature affects the blue mussels own filtration activity and physiology.

Parasites are often overlooked when we study mussel behaviour and ecology. But if we want to predict how mussels will respond to a changing climate, we also need to understand the direct and indirect effects of parasites, she says.

The researchers are already pursuing that question. Among other things, they are studying mussels from areas where parasites are currently rare or entirely absent because temperatures are too low. If a warmer climate allows parasites to establish themselves and spread into these areas, the mussels may suddenly encounter a threat they have never faced before.

The interesting question is whether those mussels will respond differently because they have not previously been exposed to parasites. That could give us a better understanding of how changes in parasite occurrence may affect mussel behaviour and ecology in the climate of the future, Pernille Kibak concludes.

Contact

PhD Student Pernille Kibak
Department of Ecoscience, Aarhus University
Mail: pfkn@ecos.au.dk
Tel.: +4552119953

Jesper Bruun
Journalist, Aarhus University
Mail: bruun@au.dk
Tel.: +4542404140

Over the past decade, Danish fruit and vegetable production has declined by almost 20 percent. Today, Denmark produces just 26 percent of the vegetables and only 9 percent of the fruit sold on the domestic market. Sixty years ago, those figures stood at 92 and 54 percent, respectively. 

The trend has fuelled debate about consumer behaviour, international competition and agricultural policy. But according to Professor Hanne Lakkenborg Kristensen from the Department of Food Science at Aarhus University, one important perspective is still missing.

"Much of the discussion focuses on how to save Danish fruit and vegetable production. We spend far less time talking about how research can make it both more sustainable and more attractive. We have enormous potential to develop cultivation systems that deliver higher-quality produce while reducing environmental impacts," she says.

Research points to practical solutions

From 2027, Denmark will introduce new nitrogen regulations aimed at protecting the aquatic environment. The proposed rules have raised concerns among vegetable growers, particularly cabbage producers, because vegetable crops often leave more residual nitrogen in the soil than cereals. At the same time, the scientific knowledge underpinning nitrogen estimates for vegetable crops remains limited. 

For Hanne Lakkenborg Kristensen, making an exemption from environmental regulations is not the answer.

Quite the opposite.

She argues that Denmark should invest far more strategically in research and innovation to develop production systems that protect waterways while maintaining a competitive horticultural sector.

Field experiments already show promising results. Intercropping, cover crops, healthy crop rotations, precision fertilisation, nutrient and biomass recycling and reduced soil tillage all appear capable of reducing nitrate leaching, maintaining high yields and even improving soil health. 

"We don't have to choose between producing more Danish vegetables and protecting the environment. But there isn't a one-size-fits-all solution. A cabbage field on sandy soil doesn't require the same management as onions grown on clay. That's why we need much more research to develop cropping systems tailored to individual crops and soil types," she says.

She also points out that fruit and vegetables differ fundamentally from much of the rest of agriculture because they are grown directly for human consumption.

"Fruit and vegetables generally have a low climate footprint because they are food - not feed. That makes them a very land-efficient way of producing food, and they can therefore play an important role in the green transition of Danish agriculture."

Transparency from field to fork

Denmark will never be self-sufficient in bananas or oranges.

But a large share of the fruit and vegetables currently imported could already be grown domestically - and often under production systems with considerable potential for lower climate and environmental impacts.

This includes apples, cabbages, root vegetables and several greenhouse crops. Modern storage technologies already make it possible to supply Danish onions and carrots almost year-round. For many other crops, investments in innovation, storage and new cultivation methods could significantly extend the Danish season.

"Today we import many fruit and vegetables that Danish growers could easily produce during the season. With the production systems we are developing, we have the opportunity to grow them with a lower climate and environmental footprint. At the same time, consumers benefit from a food system with high levels of transparency and documentation all the way from field to fork," says Hanne Lakkenborg Kristensen.

She notes that the Danish Veterinary and Food Administration's annual monitoring consistently finds fewer pesticide residues in Danish-grown fruit and vegetables than in imported produce. Danish production also operates under strict national rules on traceability, occupational health and working conditions, giving consumers a high degree of transparency. 

But production will not increase on its own.

"Growers need confidence that there is a market before they invest in new varieties, regenerative production systems, storage facilities and technology. That requires close collaboration between researchers, producers, retailers and policymakers."

Competing on quality - not price

If Danish growers are to compete with countries where labour and production costs are lower, price is unlikely to be their strongest advantage.

Quality, however, could be.

For decades, plant breeding and cultivation have focused primarily on yield, uniform size, visual appearance and transport resilience. Research is now opening up new possibilities.

The choice of varieties and cultivation methods influences far more than plant growth. It also affects taste, texture, shelf life and the concentration of a wide range of bioactive compounds. Researchers are therefore developing production systems and crop varieties that deliver superior eating quality and may also contain higher levels of health-promoting compounds. 

"Our goal isn't simply to grow more vegetables. We also want to produce vegetables with better sensory characteristics, greater diversity and higher quality. Research suggests that cultivation methods and variety selection can influence these characteristics, but we need robust scientific evidence to fully understand the effects," she says.

Ultimately, she hopes consumers will begin to look at fruit and vegetables differently.

"We readily talk about the quality of wine, coffee or cheese. Fruit and vegetables deserve the same attention. Around the dinner table, we should be talking about taste, quality and the story behind the produce - not just the price per kilogram."

Reversing the current trend is therefore about much more than increasing production.

It is about building a Danish fruit and vegetable sector that ranks among the world's most sustainable, transparent and quality-driven.

Contact

Professor Hanne Lakkenborg Kristensen
Department of Food Science, Aarhus University
Mail: hanne.kristensen@food.au.dk
Tel.: +4520698054

Jesper Bruun
Journalist, Aarhus University
Mail: bruun@au.dk
Tel.: +4542404140

This is nine per cent fewer than last year's record number of applications. However, demand for the Bachelor of Science (BSc) in Engineering programmes continues to grow.

Compared with 2024, the number of first-choice applicants has increased by 19 per cent, and by four per cent compared with last year.

Many Applicants Will Be Turned Down

Like all Danish universities, Aarhus University is required to reduce the number of study places by 2032 following a national political agreement.

As a result, many qualified applicants will be disappointed when admission decisions are released on 28 July. In practice, Aarhus University will have to reject between 40 and 50 per cent of applicants whose first choice is a Bachelor of Science (BSc) in Engineering programme.

Vice-Dean Louise Møller Haase describes the situation as paradoxical.

"This is deeply problematic both for the young people we have to disappoint and for the companies that are struggling to recruit the highly skilled engineers they need," she says.

She continues:

"For years, we have been working to address the projected shortage of highly educated engineers in Denmark. Now, prospective students are doing exactly what society needs them to do. They are applying for engineering degrees in record numbers, yet we are forced to turn many of them away."

The pressure on study places does not end with the bachelor's programmes.

By the application deadline of 1 March, the Faculty of Technical Sciences had received no fewer than 1,172 first-choice applications for its Master of Science (MSc) in Engineering programmes, despite having only 491 places available.

Louise Møller Haase fears that this will have long-term consequences for Denmark as a knowledge-based society.

"The applicants we reject today are the highly qualified professionals we will be missing tomorrow. They are the people who could have gone on to develop artificial intelligence, drive the green transition, strengthen competitive manufacturing, build our defence capabilities and protect society against cyber threats. By educating fewer engineers, we weaken Denmark's competitiveness, innovative capacity and security."

Fewer Applicants for Winter-Start Engineering Programmes
 

The overall decline in applications to the Faculty of Technical Sciences is mainly due to fewer applicants for the winter-start Bachelor of Engineering programmes (BEng).

Louise Møller Haase is not concerned by this development.

Applications for the bachelor of engineering programmes starting in the winter remain open until 1 November, so the figures we see in the summer often change considerably during the autumn.

Continued Strong Interest in AU Viborg and AU Herning

At AU Viborg, the Bachelor's degree programme in Veterinary Medicine remains one of the faculty's most sought-after programmes. Although the number of first-choice applicants has fallen slightly, demand continues to far exceed the number of available places.

Interest in the Bachelor's degree programme in Animal Science has also grown, with first-choice applications increasing by 19 per cent.

The number of applicants for the Bachelor's degree programme in Plant and Food Science remains unchanged.

The students who choose the programmes at AU Viborg will play a key role in transforming agriculture and food production. We are pleased to see such strong interest, while continuing our efforts to attract even more students to these fields," says Louise Møller Haase.

At AU Herning, demand also remains strong for the Bachelor of Engineering programme in Electrical Power Engineering.

Most applicants have chosen to study online, and Louise Møller Haase welcomes the programme's ability to attract students from across Denmark.

"We have prioritised a fully digital degree programme designed for a new group of students who live far from a university campus. This supports our ambition to educate more engineers for the green transition throughout Denmark," she says.

Admission Decisions on 28 July

Over the coming weeks, Aarhus University will assess applications and offer admission to the most qualified applicants. All applicants will receive their admission decision on 28 July.

Note: This article is based on preliminary application figures. The final figures will be published later this week.

Over the past 15 years, researchers and industry partners have developed and refined methods for cultivating sugar kelp in Danish waters. The results show that seaweed can be grown at large scale, thrives under offshore conditions, and absorbs nutrients from the surrounding marine environment as it grows.

Now, researchers believe offshore wind farms could become the next frontier for seaweed production.

We have the technology. We are ready to cultivate seaweed at scale. What we need now are partners who can use and market the products seaweed farmers are capable of producing, says Annette Bruhn, Senior Researcher at the Department of Ecoscience, Aarhus University.

More than an energy landscape

Denmark is currently undertaking a historic expansion of offshore wind energy. By 2030, vast new areas of the sea will be dedicated to renewable power generation.

For researchers and stakeholders, this presents an opportunity to rethink how marine space is used.

Instead of allocating new areas for aquaculture, seaweed can be cultivated within existing offshore wind farms. The same stretch of ocean can therefore produce both renewable energy and food.

We are not taking up new marine areas. We are using areas that have already been designated for another purpose. At the same time, we can share infrastructure, service vessels and operational resources, says Annette Bruhn.

The concept is known as multi-use and involves combining several activities within the same marine area. The goal is not only to reduce competition for space, but also to lower costs and environmental impacts by sharing infrastructure and logistics.

According to the researchers, offshore environments may offer some of the most promising conditions for seaweed cultivation.

Water exchange is high, environmental conditions are relatively stable, and field trials indicate that both yields and product quality can be exceptionally good.

We are seeing high yields, excellent quality and higher nutrient removal than we originally expected. The North Sea appears to be one of the most promising cultivation environments we have worked in, says Annette Bruhn.

A crop that grows without farmland

Interest in seaweed is not driven solely by where it can be grown.

Unlike conventional crops, seaweed requires no agricultural land, irrigation or fertilisers. Instead, it grows using sunlight and nutrients that are already present in the marine environment.

Once harvested, the biomass can be used in a wide range of applications. Seaweed can be consumed directly as food, processed into ingredients such as gelling agents, stabilisers and antioxidants, or used in animal feed and bio-based materials.

Danish studies have demonstrated that sugar kelp cultivation can remove both nitrogen and phosphorus from coastal waters. At the same time, research suggests that environmental impacts remain limited when cultivation and harvesting are managed appropriately.

Seaweed farming is therefore not a substitute for reducing nutrient emissions at their source. However, it can complement existing efforts by producing valuable biomass while removing some of the nutrients that have already entered the marine environment.

The market is the missing link

Researchers have also investigated what could happen if seaweed cultivation was integrated into the large-scale expansion of offshore wind energy.

Their analyses suggest that even modest use of the space between turbines could support substantial production of seaweed and other marine resources. The potential is significant enough to support new value chains for food, feed and biorefining.

Yet production alone does not create a market.

For Annette Bruhn, the next step is therefore to engage a much broader group of stakeholders.

We need food manufacturers and retailers to get involved. We need meal-kit companies, public kitchens and schools. These are the actors that help shape peoples eating habits.

She compares the current situation to the transformation that has taken place around legumes in recent years.

Five or ten years ago, legumes were far less visible in canteens and everyday meals. Today they have become a natural part of many diets. We would like to see the same development for seaweed.

From research project to food system

Seaweed cultivation in offshore wind farms remains a relatively young field, and researchers and industry continue to optimise cultivation systems, document environmental impacts and develop new products.

But the conversation has changed.

Where researchers once focused on whether the technology would work, attention is now turning to how it can be implemented at scale.

We know that seaweed can be cultivated. We know that we can produce large volumes of high-quality biomass, says Annette Bruhn.

The challenge now is to build stronger links between production, the food industry and consumers.

For researchers, that marks an important transition. The scientific foundations have largely been established. The next phase will be about creating the partnerships, supply chains and markets needed to turn offshore seaweed cultivation into a viable industry.

Contact

Annette Bruhn
Senior researcher, Department of Ecoscience - Marine Ecology
Tel.: +4529638034
Mail: anbr@ecos.au.dk

Jesper Bruun
Journalist, Aarhus Universitet
Tel.: +4542404140
Mail: bruun@au.dk

It is remarkable what can happen in just 30 years if we allow forests to regenerate naturally and simply leave them in peace, says Emilie Thunbo Kallesø, pointing to wood anemones and herb bennet as examples of species that emerge and enhance the biodiversity everyone talks about, but which few of us fully understand.

Planted forests with tall, densely packed trees arranged in long rows may help reduce our CO emissions and improve drinking water quality, but they do not contribute significantly to biodiversity in Denmark. My results show that forest species and ecosystems thrive much better under natural regeneration over many years, she explains.

Age Is Just a Number

The contrast is particularly visible in Lisbjerg Forest, where planted beech trees stand in dense, perfectly straight rows directly beside wild shrubs and naturally regenerated vegetation. Only a narrow strip separates the two worlds. One is dark and predominantly brown; the other is light and green.

In the naturally regenerated forest, 23 forest species and 5 ancient woodland species were identified, whereas the planted forest contained only 10 forest species and 2 ancient woodland species. So even though the two forests are almost identical in both age and location, the methods used to establish them have an enormous impact on biodiversity, says Emilie Thunbo Kallesø.

As part of her thesis project, she has examined forest areas ranging from 5 to 200 years old, and it is especially in the younger forests that species living conditions depend heavily on their surroundings. The naturally regenerated forests contain an average of 14.6 species, while the planted forests contain only 8.2 species on average. According to her, the problem is that in our enthusiasm for multifunctional forests that are expected to do everything, we often fail to allow them to establish themselves under conditions where plants and animals can truly flourish.

Forest Law or Law of Nature

Under Denmarks Green Tripartite Agreement, the aim is to plant 250,000 hectares of new forest by 2045. Of these, 100,000 hectares are to be established as untouched forest. However, according to Emilie Thunbo Kallesø, it is crucial to consider how these forests are created. If biodiversity is to be strengthened, natural regeneration should form an important part of future afforestation efforts.

The political parties behind the agreement have committed themselves to revising the Danish Forest Act, which today is primarily designed to maintain timber production. According to Emilie Thunbo Kallesø, this is the first essential step:

The Forest Act struggles to accommodate the fact that forests in reality serve purposes beyond timber production, and revision is necessary if it is also to ensure that forests benefit biodiversity, she says.

At Naturmødet in Hirtshals on 29 May, Emilie Thunbo Kallesø will present the findings of her research project. A few days later, she will defend her masters thesis as a biology student at Aarhus University.

Here you can view the full programme for Naturmødet 2026: https://naturmoedet.dk/om-naturmoedet/program-for-naturmoedet-2026

When Naturmødet kicks off on Thursday 28 May and continues for two days, there will be ample opportunity to meet researchers from Aarhus University. On the main stages, AU researchers will take part in 32 out of around 100 sessions.

For Mikkel Tamstorf, Head of the Department of Ecoscience, Naturmødet is an ideal opportunity both to bring research to the public and to take new perspectives home.

Naturmødet is the place where we can talk with citizens, organisations, decision-makers and colleagues. We exist to create new knowledge, and at Naturmødet we share it. At the same time, it is important for us to receive input in return. It is essential that our research is rooted in the questions and challenges that concern society, says Mikkel Tamstorf.

AU has its own tent

Naturmødet was first held in 2016 and, according to the organisers, has developed into one of Denmarks largest events on nature and the green transition. Last year it attracted around 30,000 visitors to roughly 660 debates, talks and activities. 

This is the second year in a row that Aarhus University will set up its own tent and, according to plan, host 60 sessions over the course of the event.

Jesper Givskov Sørensen, Head of the Department of Biology, fully supports staff participation in Hirtshals. He sees Naturmødet as a unique opportunity to strengthen dialogue between researchers and the wider public.

We are very keen to make our knowledge available, and it is an ideal opportunity for our researchers not least the younger ones to present their work, build connections and listen to the expectations and concerns that people have, says Jesper Givskov Sørensen.

Communicating knowledge is a core task

Visitors can, among other things, experience discussions about the state of lakes and the value of lowland soils, hear about plant mania in 19thcentury paintings, listen to a talk on the wild history of the horse, or get an update on the green tripartite negotiations. For children, the programme includes dissections of fish and birds.

It takes time and money to prepare and participate, but it is a core task on a par with conducting research, says Mikkel Tamstorf.

Aarhus University provides knowledge on everything from wolves and the marine environment to biodiversity and the green tripartite agreement. At a time when nature and the environment are taking up more and more space in public debate, Naturmødet gives us an important opportunity to strengthen the relationship between researchers and the public. That is an opportunity we must hold on to, he says.

Aarhus University at Naturmødet

See the programme for AUs tent (in Danish)

Eight different departments and actors across the Nat and Tech faculties stand behind the joint AU stand

Full programme for Naturmødet

Contact

Signe Brokjær Nielsen signe.brokjaer@ecos.au.dk 53 17 34 54

Marianne Knudsen mk@bio.au.dk 60 77 71 88

Folkemødet brings together politicians, organisations, businesses and citizens for three days of debate and democratic dialogue. This year, Tech will contribute with research and perspectives on topics including cybersecurity, ultra-processed foods, antibiotic resistance and the future of healthcare.

Folkemødet offers a unique opportunity to bring research into direct dialogue with society. We work with solutions to some of the most pressing challenges of our time, and here we can test our knowledge, be challenged and further develop it together with decision-makers and the public, says Dean Eskild Holm Nielsen.

Tech researchers will participate in a wide range of debates and events throughout the festival. Activities will take place aboard the research vessel Aurora together with the rest of Aarhus University, in the Tech Tent alongside DTU, AAU, SDU, IDA and Engineer the Future, and at the BIO stage together with the research centre CORC.

Future solutions and the role of universities

What will healthcare look like when technology becomes an integrated part of diagnosis and treatment? How prepared are we to monitor and manage aspects of our own health while specialists increasingly work remotely? And can we trust the technology that supports these developments?

These are some of the questions explored in a debate on the future healthcare system, where researchers, clinicians and technology developers will discuss how innovation is reshaping welfare and healthcare services.

Another key topic this year is cybersecurity an issue that already affects governments, businesses and citizens alike. In the debate Reality Is Testing Our Cybersecurity, researchers, ethical hackers and public authorities will discuss how society can protect critical digital infrastructure as threats continue to evolve in both scale and complexity.

What unites these discussions is their foundation in research closely connected to real-world societal challenges and developed in collaboration with public authorities and industry partners.

Folkemødet also provides an opportunity to address broader questions about the role of research and universities in society.

In a debate on societys contract with universities, researchers and stakeholders will examine how research creates value and what society can reasonably expect from higher education institutions. The conversation will focus not only on generating new knowledge, but also on collaboration and societal impact: How do we turn research into practical solutions? And how can universities actively contribute to the green transition, public health and security?

Experience research beyond the debate stage

Folkemødet is about far more than panel discussions. It is also a place where research can be experienced in new and engaging ways.

One of Techs returning initiatives is TechSlam, where researchers present their work in short, dynamic performances alongside professional rappers. Complex research topics are transformed into accessible and entertaining experiences that bring audiences closer to the science behind them. Last year, Tech took home the win with rapper Flammen and Professor Lars Ottosen and this year the question is whether they can do it again.

Visitors will also have the chance to literally taste the research. In an event centred on beer brewing, Tech and researchers from Denmarks other universities will demonstrate how technology and biotechnology contribute to the development of new food products. Last year, Tech won first prize with a beer created by Associate Professors Bo Spange Sørensen and Henning Sejer Jakobsen, and this year guests are invited to stop by and see whether the success can be repeated.

Another debate will focus on Danish fruit and vegetables and how research can support a more sustainable food production system.

Together, these activities showcase the breadth of research at Tech from highly technical innovations to solutions that directly influence everyday life.

Read more about Aarhus Universitys participation in Folkemødet here (in Danish).

The agreement has now been expanded. Going forward, Lotte Thøgersen will spend part of her working time as Director of Industry Collaboration at the Faculty of Technical Sciences at Aarhus University. The arrangement will run for the next two years, during which she will particularly focus on industry-related activities within the new work-integrated Masters degree programmes.

We have chosen a joint initiative between VIA and Aarhus University because it provides the best conditions for an equal partnership between the two institutions and the greatest potential to create coherent engineering education pathways that benefit industry, says Eskild Holm Nielsen, Dean of the Faculty of Technical Sciences at Aarhus University.

The collaboration agreement means, among other things, that Bachelors of engineering educated at VIA University College in Horsens will have the opportunity to progress directly into a relevant masters degree programme at Aarhus University. Initially, the collaboration will focus on two programmes with specialisations in cybersecurity, and in climate, utilities and water technologyan initiative that will benefit companies across Central Denmark Region, explains Lotte Thøgersen:

By working together on industry collaboration, VIA and Aarhus University can attract and retain even more of the talented students that technology-based companies in Central Denmark Region and the rest of Denmark are seeking. Our goal is to get even closer to the needs and wishes of companies and to offer students a more industry-oriented and relevant educationultimately strengthening Denmarks technological development, says Lotte Thøgersen.

With the new industry-based masters programmes, companies can employ a fully qualified diploma engineer on a part-time basis while the employee completes a university masters degree and works on the companys own development projects as part of their studies.

The collaboration applies to both Danish students and students from the EU.

Focus on the foods of the future

This year, the theme in our tent is foods of the future, with a special focus on proteins and rethinking how we view, taste, and create food in the years to come. Why is this important? Because the way we produce and consume food is changing. Climate change, resource scarcity, and new consumer habits are pushing us to think differently - especially when it comes to proteins, which are a key part of our diet.

When you visit our tent, youll have the opportunity to experience firsthand how research is shaping and developing the foods of the future. You can taste, explore, and learn about solutions that can help ensure sustainability, quality, and great taste when we gather around the dining table in the future.

What can you experience in the tent?

From May 2123, 2026, we invite you into our tent, where we take you on a journey through the foods of the future, with a special focus on proteins.

Across almost all activities, we explore one central question: What does it take for a protein to become a food? The answer is far from simple - it unfolds through a series of engaging cases where you can meet the researchers behind the work and experience food research in practice.

Can you bake a cake without eggs?
In our first case, we dive into plant proteins as a substitute for eggs as ingredient. Here, you can learn why eggs are so difficult to replace and which functions proteins need to deliver in complex foods. You can experience how proteins function in foaming, emulsification, and gelation - and of course taste cake made with plant proteins as egg replacers. You can also explore ingredients such as soy, lupin, lentils, and chickpeas, and learn why research into plant-based alternatives is so important for the future of food.

Can we bake bread using grains other than wheat?
In another case, we focus on barley and investigate whether alternative grains can play a larger role in future bread production. Here, you can taste bread made with barley, wheat, and rye, participate in consumer studies, and learn what happens to proteins in the dough. Youll also gain insight into how research on grains and proteins can contribute to more sustainable food systems.

Can sweet potatoes play a bigger role on our plates?
We also take a closer look at sweet potatoes and their potential in future foods. What is the difference between sweet potatoes and regular potatoes? Can they be grown in Nordic climates? And how can they contribute to greater diversity in our diets? Youll have the chance to taste crispy sweet potato chips and take a closer look at the plants themselves.

Is cultured meat a solution for future protein?
Finally, you can learn more about cultured meat as a possible alternative to conventional meat production. We highlight climate impact and resource use and provide insight into how proteins are used in developing cultured meat. You can, for example, see visual comparisons of CO footprints from different production methods and gain a better understanding of the challenges and opportunities within future animal-based foods.

Along the way, youll meet researchers from a wide range of the departments research groups, ready to share their knowledge, answer your questions, and give you a unique insight into some of the latest food research - served fresh.

We look forward to welcoming you to three days full of taste, knowledge, and experiences!

Practical information

Opening hours

• Thursday, May 21: 14:0018:00
• Friday, May 22: 10:0018:00
• Saturday, May 23: 10:0015:00

Admission to Madens Folkemøde is free.

Address
Torvet, 4800 Nykøbing Falster

The Department of Food Science tent location: Kirkepladsen

Visit the official Madens Folkemøde website.

With 140 core partners across 29 countries, a Head Office in Denmark and 8 Co-location Centres across Europe, EIT Water will begin work in 2026 by bringing industry, academia, the public sector and innovators into one central hub, creating the conditions for startups, new technologies, education programmes and innovation projects to grow around Europes most urgent water challenges.

In 2026, EIT will provide a 5 million EUR grant to establish the KIC and to develop EIT Waters Strategic Agenda and first Business Plan. Complementing this, the PDJF funding will enable early pilot activities that bring together industry, academia and the public sector to test new approaches for water resilience, circularity and sustainable water management. These pilot activities will include open innovation calls, mapping of European demonstration sites and mentors, strategic planning efforts, and a series of entrepreneurial education activities such as hackathons across Europe. A significant share of the PDJF donation is also earmarked for open calls that support collaboration between researchers and industry.

The Grundfos Foundation wishes to strengthen collaboration between research environments and industry within the water sector, providing a significant lift to European innovation in water technology. That is why EIT Water will directly support new cross-sectorial innovation partnerships, explains Kim Nøhr Skibsted, Executive Director, Grundfos Foundation.

For more information, please contact communications@eitwater.eu

This is why Aarhus University will open a new specialisation in cybersecurity for MSc engineering students this summer.

Denmark is one of the most digitalised countries in the world. Large parts of our communication, utility infrastructure, economy, business sector and public administration now run on digital platforms. This makes us vulnerable to cybercrime and cyberattacks, and society has an urgent need for highly specialised engineers with expertise in this field, says Mikael Bergholz Knudsen, Head of the Department of Electrical and Computer Engineering at Aarhus University.

University stepping up efforts

Wars no longer take place only on the frontline or through aerial bombardments and missile strikes. They also unfold in server rooms, networks and systems that keep society running.

Every website, email, app and smart device connected to the internet can potentially provide unauthorised access. A single attack can hit the power grid, disable hospitals IT systems or halt production in companies.

If we want to prevent attacks, we must stay ahead in technological development, emphasises Mikael Bergholz Knudsen:

We need to move quickly. Many people underestimate our vulnerability, and we must educate engineers who can build far more robust security around our digital systems.

Denmark is already facing a shortage of cyber engineers, and demand continues to grow. Several analyses point to a shortfall of 15,00020,000 IT specialists in the coming years.

This concerns Mikkel Haarder, Deputy Director of the Confederation of Danish Industry (DI), responsible for research, education and diversity:

The shortage of engineers with cybersecurity skills is already a challenge for many Danish companies. It affects both companies competitiveness and our overall resilience in a digital society.

He therefore welcomes the new educational initiative at Aarhus University:

It is very positive that Aarhus University is now strengthening the education of MSc engineers specialising in cybersecurity. Denmark needs a strong talent pipeline in this area and the need is growing rapidly.

Education strengthens Denmarks digital defence

The new cyber engineers will learn to protect IT systems, networks and data against digital attacks, while developing a deep understanding of the defence-strategic dimensions of information security.

Our students must learn to think like hostile hackers so that they can stay two steps ahead at all times. Research-based education plays a crucial role in strengthening Denmarks overall digital defence, says Mikael Bergholz Knudsen.

He elaborates:

We can buy technology from abroad. We can sign contracts and upgrade defence systems. But we cannot import originality and judgement. We want to educate engineers who can analyse threats, understand people, assess consequences and translate knowledge into concrete technical choices and innovation in Danish companies.

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Cybersecurity at AU

Strengthening cybersecurity is a key part of Aarhus Universitys Strategy 2030.
Read the strategyic focus on cyber security here.

AU is investing DKK 300 million in research, education and innovation within cybersecurity.
Read more about AU Cyber here.

Want to learn more about cybersecurity?
Read about engineering research in cybersecurity at the Department of Electrical and Computer Engineering.

Interested in cryptography?
Read about research in cryptography and cybersecurity at the Department of Computer Science.

Degree programmes with a focus on cybersecurity

At Aarhus University, students can specialise in cybersecurity in the MSc in Engineering programmes in Computer Engineering and Electrical Engineering, as well as in the Masters degree programme in Computer Science.

Associate Professor Freja Chabert Østerstrøm from the Department of Environmental Science at Aarhus University participated in the international research collaboration, in which 159 scientists from 21 countries analyzed the unusual eruption and its implications for climate and atmospheric chemistry.

We have never before observed such large quantities of water vapor from a volcanic eruption. The amount corresponds to about 20 percent of the water content in the stratosphere across the entire Southern Hemisphere, says Freja Chabert Østerstrøm.

An eruption of unprecedented power

The eruption began 150 meters below sea level and was so intense that the plume reached a height of 58 kilometers, the highest ever recorded in the satellite era. Parts of the plume even reached the mesosphere. Within the first hour, it had spread to a width of 400 km and ultimately reached a diameter of about 600 km.

The explosion injected about 150 million tons of water vapor into the stratosphere, roughly 10 percent of the stratospheres total water vapor. Most of the water came from seawater and magma, and because Hunga sat at an ideal depth beneath the sea, conditions were perfect for a so-called "wet explosive" eruption.

Under normal circumstances, the boundary between the troposphere and stratosphere, the tropopause, acts as a cold trap, preventing water vapor from rising. But this explosion was powerful enough to breach that barrier.

What makes Hunga so special is the combination of water and sulfate particles that reached unprecedented altitudes. It has completely changed our view of what happens after a volcanic eruption. We simply didnt think this was possible, says Freja Chabert Østerstrøm.

The stratosphere is usually a dry and stable layer, where sunlight and low temperatures keep chemical reactions in check. But with the injection of water, significant changes occurred. Water affects temperature and accelerates chemical processes that deplete ozone, in part by forming hydroxyl radicals (OH), which help turn sulfur dioxide (about 0.5 million tons released) into sulfuric acid particles (sulfate aerosols).

Water vapor has a dual effect. It cools the stratosphere but also shifts the chemical balance and particle formation. This allows reactions that typically occur only over the poles to happen elsewhere, and weve seen that here, Østerstrøm explains.

In the months following the eruption, large ozone losses were recorded outside polar regions. Locally over the Southern Hemisphere, researchers observed up to 14% ozone loss and 22% hydrogen chloride (HCl) reduction in the mid-stratosphere, up to 5% ozone loss occurred within the first two weeks after the eruption, with up to 40% on a single day.

Its highly unusual. And it happened because the water vapor and volcanic particles accelerated reactions that break down ozone, explains Freja Chabert Østerstrøm.

A volcano with limited climate effect

Large volcanic eruptions are normally associated with global cooling. Sulfuric acid particles formed from sulfur dioxide spread through the stratosphere and reflect sunlight. After Mount Pinatubo erupted in 1991, for example, global temperatures dropped by about 0.5 degrees for two years.

But the Hunga eruption defied that pattern. The water vapor counteracted the cooling from sulfur particles because water behaves very differently in the atmosphere. Water vapor absorbs heat and acts as a greenhouse gas, warming Earths surface.

This is the first time we've seen this type of response from a volcanic eruption, says Østerstrøm.

Climate models estimate the overall effect to be around -0.05°C during 20222023, making it difficult to detect. But it highlights the substantial impact water vapor can have in the stratosphere, forcing researchers to reconsider their assumptions in volcanic climate models.

New insights into supervolcanoes

One of the biggest surprises was how long the water remained in the atmosphere. It only began to dissipate in early 2024, nearly a year and a half after the eruption. In 2022, 78% of the water stayed in the Southern Hemisphere, and remnants of the plume remain measurable in 2025.

The stratosphere simply isnt designed to handle that much water. It changes how we understand atmospheric chemistry, and also how we interpret earlier supervolcano eruptions, explains Østerstrøm.

The Hunga eruption injected such a massive amount of water that it could indirectly inform us about what might have happened during even larger, prehistoric eruptions, so-called supervolcanoes. Since weve never before had the technology to measure such water quantities, Hunga becomes a key example in future climate models.

The Hunga eruption was unlike anything observed before, says Yunqian Zhu, research associate at the University of Colorado Boulder and one of the main authors of the report. It taught us how profoundly water-rich eruptions can affect the stratosphere and how essential global cooperation is in capturing and understanding such rare events.

How water vapor affects the ozone layer

• Normally absent in the stratosphere, water vapor disrupts its stability.
• Rising water vapor changes temperature and triggers new chemical reactions.
• Water reacts with sulfur dioxide (SO) to form sulfuric acid (HSO), which condenses into aerosols.
• These aerosols serve as reaction surfaces where harmful halogen compounds (like HCl) are transformed into free radicals.
• These radicals destroy ozone (O), not only over the poles but also in tropical and mid-latitudes.
• The result: lower ozone levels, increased surface UV radiation, and changes in atmospheric energy balance.

Associate Professor Freja Chabert Østerstrøm 
Department of Environmental Science, Aarhus University 
Mail: freja@envs.au.dk
Tel.: +4587150623