ETH News

Natural forest regeneration is hailed as a cost-effective way to restore biodiversity and sequester carbon. However, the fragmentation of tropical forests has restricted the movement of large birds limiting their capacity to disperse seeds and restore healthy forests.

Researchers at ETH Zurich led by Robert Boes are developing specific solutions to optimise electricity production from Swiss hydropower plants. This will ensure that hydropower remains the backbone of Switzerland’s electricity supply in the future.

Christoph Schär is one of the Swiss climate scientists who have shaped high-resolution climate modelling. He is now retiring after more than 35 years at ETH Zurich. In this portrait, he explains why he himself never tires of researching climate change.

The cost of removing large quantities of CO₂ from the air will fall in the medium term, but not as much as previously hoped. This is the conclusion reached by ETH researchers on the basis of new calculations. Efforts to reduce carbon emissions should therefore continue at pace, says the research team.

For Anthony Patt, Europe’s ambitious plans for a hydrogen economy may be too ambitious, tipping the scales towards the interests of the fossil fuel industry, rather than energy consumers and the climate. Switzerland should be careful before jumping fully on board, he argues.

As Thomas Bernauer sees it, information on the impact that different segments of the population have on the climate is an essential ingredient in making climate policy measures fair and acceptable to the majority.

More and more people are afraid of climate change. For Cyril Brunner, this also has to do with how we talk about climate. We should focus less on problems and instead spend more time discussing solutions, suggests the climate researcher at the start of the year.

Capturing carbon dioxide (CO₂) from the atmosphere and storing it either in recycled concrete aggregate or in geological reservoirs in Iceland is not only technically feasible, but also has a positive carbon footprint. These are the findings of a pilot project lead by ETH Zurich and commissioned by the Swiss confederation.

People living on the in low-lying coastal areas will be at even greater risk from cyclones in the future. Natural ecosystems offer protection, but this protection has decreased in recent years and is expected to continue to decline. This is a finding of a model study by an international team of researchers led by ETH Zurich.

New study estimates that natural forest recovery could capture approximately 226 Gigatonnes (Gt) of carbon, but only if we also reduce greenhouse gas emissions. Achieving these results requires community-driven efforts to conserve and restore biodiversity.

The Alps are being increasingly affected by floods and droughts. According to Manuela Brunner, we can do something about this problem: use water more sparingly and think about hazard protection in broader terms.

They set out to study the Congo Basin’s carbon cycle and in the process have become aware of one of the world’s darkest blackwater rivers: the Ruki. In the first study on this major jungle river, an international research team led by ETH Zurich explains how this blackness comes about and what it says about the river system’s carbon balance.

ETH Professor Sonia Seneviratne has been elected as Vice-Chair of the Working Group I of the Bureau of the Intergovernmental Panel on Climate Change (IPCC). In order to take on this new responsibility, she is stepping down as Associate Vice President for Sustainability at ETH Zurich. In this interview she talks about her old and new positions.

An extraordinary heat wave is assailing the world’s oceans with an intensity that is surprising climate researchers. Environmental physicist Nicolas Gruber provides some context.

Our oceans are acidifying rapidly. Climate researchers from ETH Zurich are now illustrating these chemical changes with colour-coded stripes. Global observations of ocean acidification over the last four decades serve as the basis.

Through a new bilateral carbon trading pact, Switzerland is poised to fund thousands of household biogas reactors in Malawi. Marc Kalina has worked with biogas projects across Southern Africa and explains why they often fail to make their promised impact.

The risk of fatal heatwaves has risen sharply over the past 20 years. In the future, such extreme weather will become more frequent and heat-related excess mortality will increase. Europe will be particularly affected, as ETH Zurich researchers show.

For the first time, researchers combined human and ecological factors to analyse the global scale of non-native tree species invasions. Human activity in hotspots of global trade, such as maritime ports, is linked to an increased likelihood of non-native tree species invasions. However, a high diversity of native tree species can help to curb the intensity of such invasions.

Malte Toetzke calls for more ambitious standards in the voluntary carbon offset market. While this would lead to fewer projects getting funded, the benefit for the climate would be greater overall. 

When microorganisms break down organic material in the soil, they actively release CO₂ into the atmosphere. This process is called heterotrophic respiration. A novel model shows that these emissions could surge by up to 40 percent by the end of the century – most significantly in the polar regions.

Innovative production technologies are crucial to the chemical industry’s net-zero endeavour – but they’re not always enough, says Paolo Gabrielli.

Heavier rain, longer droughts, melting glaciers: climate change has a dramatic impact on the global water cycle.

The expansion of hydropower generation often leads to conflicts of interest, both in Switzerland and beyond. Researchers from ETH Zurich are trying to find a basis for compromise that serves the public interest.

ETH Zurich researchers have found that droughts and land water variability have had an increasing effect on the carbon cycle in the tropics over the last sixty years. Most climate models fail to capture this observation. This could mean that terrestrial ecosystems could absorb less CO₂ than expected in their role as carbon sinks in the future.

Political debate is vital for a functioning democracy. And when it comes to complex issues such as climate change, scientists should be able to share their expertise and help shape opinion, says Reto Knutti.

Increasing summer heat and drought are affecting European forests – some years, trees brown prematurely and some even start to die back. Researchers from ETH Zurich and the WSL are showing how exceptional weather conditions over several years are turning forests brown.

In the Forest Laboratory "Waldlabor" on Hönggerberg, ETH Zurich researchers investigate the storage and transport processes of water in the forest. Recently they showed that forest-floor litter and deadwood have a far larger influence on the forest water balance than expected.

A study by researchers at ETH Zurich shows for the first time how a relaxation of Swiss spatial planning policy would affect the locations of wind turbines. If the aim is to have as few wind turbines as possible in the Alps and in Switzerland in general, it would be worth considering using windy agricultural areas on the western Swiss Plateau.

Many regions have suffered from heatwaves in recent years. But exactly how these form is still a matter of debate. Two researchers at ETH Zurich have now found a nuanced answer.

Atmospheric chemist Thomas Peter retired at the end of January. A profile of a man who taught us about the properties and processes of suspended particles and helped shape the second-largest department at ETH Zurich.

Efforts to restore degraded ecosystems have so far fallen short of meeting global targets. Sound restoration must better incorporate social processes promoting equity in order to effectively benefit people, climate and biodiversity, says Sara Löfqvist.

One of the greatest unknowns in climate change is the question of how particulate matter affects clouds. Yu Wang is using machine learning and satellite data to investigate the surprising role of these tiny particles in the atmosphere.

Until now, mountain regions have been largely spared from biological invasions. But a new monitoring study shows that alien plants are spreading rapidly to higher altitudes along transport routes worldwide.

There has been a great deal of media focus on the near-total lack of snow in Swiss ski resorts at the beginning of the year. Sonia Seneviratne explains why we will have to get used to this scenario and what needs to be done about it.

A new study by ETH Zurich researchers reveals that if Europe fails to immediately invest 302 billion euros in climate-relevant infrastructure, it will not reach its target of net-zero greenhouse gas emissions by 2050.

While the insufficient measures increasingly argue against reaching the 1.5-degree target, we could still achieve it with a rapid reduction in methane emissions, writes Cyril Brunner.

While the economic impacts of climate policy are generally perceived as costs, Anthony Patt proposes the opposite perspective. For Switzerland, converting the energy system and reaching the net-zero target may net benefit the economy, he finds.

The 2022 summer has shown us again how climate is becoming more extreme year by year. Sticking to business-as-usual and counting on adaptation alone will not work. Only a rapid phase out of fossil fuels will prevent the worst, says Sonia Seneviratne.  

High temperatures, fuelled by climate change, dried out soils across Europe and the Northern Hemisphere this summer, finds a team of climate scientists led by ETH Zurich in the name of the World Weather Attribution group.

Researchers from ETH Zurich are studying how alpine vegetation is responding to a warming climate – and how some plant communities are continuing to stand firm against newcomers from lower elevations.

A team of researchers from ETH Zurich and WSL travelled to Svalbard this summer to take a closer look at the phenomenon of Arctic greening. Lead principal investigator Sebastian Doetterl discusses research in the face of polar bears, airline strikes and war.

Researchers at ETH Zurich and WSL have for the first time reconstructed the extent of Switzerland’s glacier ice loss in the 20th century. For this purpose, the researchers used historical imagery and conclude that the country’s glaciers lost half their volume between 1931 and 2016.

Researchers from ETH Zurich have established that the destruction of ozone over the Arctic in the spring causes abnormal weather throughout the northern hemisphere, with many places being warmer and drier than average – or too wet.

Researchers from ETH Zurich and TU Delft have developed a model to generate hundreds of ways in which Europe’s energy system can become green and self-sufficient by 2050. They have made their results available on an interactive platform to provide a clearer picture of all the various options and their associated trade-offs.

Human geographer Christine Eriksen and physicist David Bresch conduct research into weather and climate risks. Their methods may be different, but they agree that the scale of a disaster is often determined more by societal decisions than by the natural hazard itself.  

Aerosols in the atmosphere react to incident sunlight. This light is amplified in the interior of the aerosol droplets and particles, accelerating reactions. ETH researchers have now been able to demonstrate and quantify this effect and recommend factoring it into future climate models.

Russia’s invasion of Ukraine has suddenly shifted the debate on security policy. An interview for Globe magazine with ETH researchers Myriam Dunn Cavelty, Vally Koubi und Giovanni Sansavini on the subject of security and risk conducted in January has been overtaken by events and will therefore not go to print. We want to nevertheless make it available to you online. A lot of the questions and answers would be different today. Read it for yourself.  

ETH spin-off Climeworks is specialised in technology that filters CO₂ directly from the air. The company secured CHF 600 million in investment in its latest equity round, allowing it to invest in new large-​scale air capture facilities.

Anthony Patt has contributed to the new IPCC report on mitigation of climate change. Since the last report in 2014, the odds for phasing out fossil energy have changed; a net-zero world is achievable now, even if the way remains long.

The Swiss Polar Institute has launched a four-year study led by EPFL in which researchers from several other Swiss institutions are investigating the impact of climate change on Greenland’s fjord ecosystems. Research groups from ETH Zurich are also involved.  

Politicians and the media struggle with predictions. This is more a problem resulting from a poor understanding of uncertainties than from the reliability of models, argues Reto Knutti.

Thomas Bernauer contributed to the latest IPCC report on adaptation to climate change. He sees nature and good governance as our most important resources for coping with the effects of climate change.

Until now, research assumed that the vast forest area of the Congo Basin, like other tropical forests, releases large amounts of nitrous oxide and binds methane. Researchers at ETH Zurich have now shown that it behaves differently: methane is released, while nitrous oxide emissions are smaller than thought.

Most trees live in symbiosis with fungi. ETH Zurich researchers show just how important this partnership is for tree growth through the first-ever comprehensive data analysis compiled for European forests on a massive scale.

Without stronger climate action, the five biggest emitters will double the number of countries regularly experiencing extreme hot years by 2030.

Núria Casacuberta Arola studies water circulation using radionuclides to understand the role of the oceans in mitigating climate change.

While much is known about extreme weather events on land, there has been little research into those that occur in the ocean. A study led by ETH Zurich uses models to show for the first time that marine heatwaves, and extremes with high acidity or low oxygen can also occur conjointly – with difficult to foresee consequences for marine life.

Ambitions to make hydrogen a key energy carrier for a climate friendly future are misguided, says Anthony Patt. Wherever possible, including ground transportation and heating, we should replace fossil fuels with the direct use of renewable electricity.

Climate scientists from around the world have just published an open letter on COP26.

The CO₂-reducing effect of the pandemic has fizzled out, as the Global Carbon Project confirms in its latest report on greenhouse gas emissions. Nicolas Gruber nevertheless identifies some bright spots.

Researchers at ETH Zurich have developed the process technology that can produce carbon-neutral transportation fuels from sunlight and air. Now, in a Nature publication, they demonstrate the stable and reliable operation of the solar mini-refinery under real on-sun conditions. And they show a way to introduce solar fuels to the market without additional carbon taxes.

It will take more than a long-term target for 2050 to achieve climate neutrality, says Reto Knutti. Policymakers must take a consistent approach towards net zero, and define a reduction path with specific measures and interim targets.

Ocean warming caused by anthropogenic greenhouse-gas emissions will prompt many species of marine plankton to seek out new habitats, in some cases as a matter of sur-vival. ETH Zurich researchers expect many organisms to head to the poles and form new communities – with unforeseeable consequences for marine food webs.

Michael Kreuzer, Professor of Animal Nutrition and pioneer in the prevention of greenhouse gas emissions from livestock, is retiring after 27 years at ETH Zurich.

ETH Fellow Nadia Shardt is researching how water droplets in clouds freeze to form ice, and the role played by particles in this process. She has developed an innovative apparatus specifically for this purpose. She hopes that her findings will enable climate models to produce more accurate forecasts.

Climate researcher Sonia Seneviratne contributed to the latest assessment report of the Intergovernmental Panel on Climate Change (IPCC). As she highlights here,  the new report clearly demonstrates that we can’t afford to lose any more time when it comes to climate change.

Torrential rain and flooding have dominated the weather over the past few weeks. To forecast these weather events with greater accuracy and gain a better understanding of them against the backdrop of global climate change, ETH Zurich and partners are developing a new generation of high-resolution weather and climate models.

We know that CO2 is warming the planet. But if we want to understand its consequences and avert risks, more accurate weather and climate models are crucial, says Nicolas Gruber.

Based on observational data from Europe, climate researchers from ETH Zurich have shown for the first time that forests lead to a rise in precipitation. Their analyses also revealed that if the available agricultural land were reforested, the amount of precipitation in Europe could increase by more than 7 percent.

This summer, students from ETH Zurich will test various technologies on the Limmat for the automatic removal of waste. The Autonomous River Cleanup project is starting with rivers to tackle the global problem of marine pollution.

Konstantinos Boulouchos spent years helping to shape Swiss energy research. Following his retirement, the charismatic Emeritus Professor of Energy Technology can now look back on more than 30 years at ETH Zurich – time to get philosophical.

A cultural landscape reflects the combined activity of nature and humans. Where has the equilibrium of this union been lost? And how can we restore the balance? 

The level of self-sufficiency indicates the extent to which agricultural performance ensures food security. But it’s not geared to the challenges that confront agriculture today, says Roman Hüppi.

The benefits of strict climate policies are often underestimated in public debate, while the costs are generally overestimated, says Lucas Bretschger. Climate protection does not have a negative impact on economic development.

Although measures taken to mitigate the effects of climate change are generally associated with energy levies and high costs, the opposite is actually true: the switch to renewable sources is set to reduce energy prices significantly.

In the first Swiss National Climate Day, ETH Zurich participates with a fresh discussion format on some of the most fundamental questions of life. In addition, researchers are joining live from Bern.

The climate action potential of carbon capture during the processing of biomass feedstock is considerable, ETH Zurich researchers have calculated. If this potential is to be fully exploited in practice, however, there are challenges to overcome.

An international research team including scientists from ETH Zurich has shown that almost all the world’s glaciers are becoming thinner and losing mass’ and that these changes are picking up pace. The team’s analysis is the most comprehensive and accurate of its kind to date.

The European Research Council has decided on the recipients of its lucrative Advanced Grants. Researchers at ETH Zurich were awarded two grants – one in political science and the other in climate research. ETH is set to receive around CHF 6.6 million.

The scientific community is taking a clear stand on the CO₂ Act. Given their expertise, they are not only permitted, but obliged to do so, asserts Reto Knutti.

The risk of people being forced from their homes by flooding increases by half for each additional degree of global warming, as an international research team led by the Weather and Climate Risks Group at ETH Zurich demonstrate.

Making agriculture climate-neutral has a high cost – which some rich countries might be willing to accept, ETH Zurich researchers find.

ETH Zurich and University of California Santa Barbara researchers reveal the extent to which rivers across the USA are losing flow to aquifers.

River flow has changed significantly worldwide in recent decades. An international research team led by ETH Zurich has now demonstrated that it is climate change, rather than water and land management, that plays a crucial role at a global level.

For Switzerland to become climate neutral, there’s no way around electric mobility. But to get e-cars going, the public must push for charging stations where people live, argues Anthony Patt. 

Terrestrial ecosystems help mitigate climate change by absorbing large amounts of carbon from the atmosphere. A new study now confirms that changing climate conditions could reduce this effect because in warmer and wetter areas, carbon stored in the soil is released back into the atmosphere more quickly.

A digital twin of our planet is to simulate the Earth system in future. It is intended to support policy-makers in taking appropriate measures to better prepare for extreme events. A new strategy paper by European scientists and ETH Zurich computer scientists shows how this can be achieved.

The second episode of the uncertainty series of the ETH podcast is dedicated to the topic of uncertainty in climate change.

The coronavirus crisis has triggered a boom in virtual collaboration as an alternative to flying. Might it be possible to seize on this experience to shape the future of sustainable mobility?

Oxygen levels in the ancient oceans were surprisingly resilient to climate change, new research suggests.

ETH Zurich researchers conducted an experiment to investigate the initial steps in the formation of aerosols. Their findings are now aiding efforts to better understand and model that process – for example, the formation of clouds in the atmosphere.

More and more ETH Zurich researchers are taking the plunge into entrepreneurship. By launching spin-offs, they hope to turn their lab findings into solutions that can help stem the rise in atmospheric carbon dioxide.

ETH climate researcher Daniela Domeisen has documented how the stratosphere influences extreme weather events. What surprised her was the sheer range of potential impacts. She explains what this means for climate research and long-term weather forecasts.

Meeting the goals of the Paris Agreement means embracing a sustainable transition to renewables. Yet analyses suggest that decarbonisation can only be achieved with targeted government support for the right technologies.

When it gets warmer, organisms rise higher from the lowlands. Researchers from ETH and WSL investigated what could happen to plant communities on alpine grasslands if grasshoppers from lower elevations settled there.

Civil society and governments struggle to take action when it comes to climate change. So what’s the solution? We asked climate researcher Reto Knutti and climate strike advocate Marie-Claire Graf for their perspectives.

Precisely when will the long-lost US aircraft “Dakota” re-emerge from the Gauli Glacier? Radioactive traces from the Cold War now indicate that this will happen soon.

Researchers at ETH Zurich have identified a self-regulating mechanism in European deciduous trees that limits their growing-season length: Trees that photosynthesise more in spring and summer lose their leaves earlier in autumn.

A team of researchers from ETH Zurich has used simulations on the CSCS supercomputer "Piz Daint" to investigate how ageing mechanisms of soot particles in the atmosphere affect cloud formation. The results show that the influence of ozone and sulfuric acid on soot ageing alters cloud formation and, ultimately, the climate.

The guiding principle for global climate policy is shifting from mistrust to collaboration, says Anthony Patt. Interestingly, nations' answer to the coronavirus can help to clarify how.