The heat is on

How climate change is affecting extreme weather and ecosystems – and what it means for us

News from 04/12/2024

In recent years, Leipzig has become a hotspot for climate research. Two young scientists have been instrumental in this progress, contributing to the University’s leading international position with their research: junior professor Sebastian Sippel and Professor Ana Bastos. They are bringing together the disciplines of meteorology, earth system science and ecology to answer the most pressing questions of our time: How is climate change reshaping the dynamics of extreme weather events? And how do such events affect our ecosystems? Their research not only provides valuable insights, but also contributes to finding solutions for a sustainable future.

Brennender Wlad — Among the extreme weather events that Ana Bastos and Sebastian Sippel focus on are forest fires. Photo: iStock

Focus on climate attribution

Sebastian Sippel, recent winner of the Heinz Maier-Leibnitz Prize, is fully committed to climate attribution research. The 36-year-old’s work revolves around the question of how extreme weather events – such as the increasing frequency of heatwaves and droughts – are influenced by climate change, and what the consequences are. He is investigating how models represent these extreme events and whether they can adequately simulate reality: “In recent years we have seen record-breaking heat events. This raises questions: Should we prepare for more intense heatwaves? And how well can our models depict such events?”

There is no doubting the importance of this research. The better we understand how climate change contributes to these extreme events, the better we can prepare for them and take action. Sebastian Sippel is particularly interested in better understanding the impact of these extreme events on human life and the environment. “Climate change is affecting daily weather patterns around the world – this is not a future prediction, it is already a reality,” he says. His work at Leipzig University combines climate physics with ecosystem analysis, helping to understand the complex interactions between weather extremes and climate change.

Forests in a changing climate

Ana Bastos, who joined the Institute for Earth System Research and Remote Sensing at Leipzig University in May 2024, brings an entirely new perspective to the discussion. Her research focuses on the bidirectional interactions between the land surface and the atmosphere. The impact of climate extremes on ecosystems, especially forests, is of particular interest to her. “Forests are key carbon reservoirs. However, extreme events such as drought, insect infestation and forest fires are putting these reservoirs under enormous stress. This could put climate protection at risk in the long term,” Ana Bastos explains. Her research shows that under extreme drought conditions, forests release more carbon than they are able to store – a vicious circle that could further exacerbate the climate crisis.

enlarge the image: Trockener, rissiger Boden und ein Löwenzahn der dort wächst — Cracked soil is evidence of drought and ecological vulnerability. Photo: Colourbox

With her ERC Starting Grant, the 38-year-old is investigating the vulnerability of forests to climate extremes and asking: why are some forests more resilient than others? And what does this mean for global climate protection? Bastos’s work has already yielded worrying findings. Together with her team, she calculated that extreme heat events in 2023 worsened the carbon balance of the global land biosphere by 1.7 billion tonnes – an alarming sign of the vulnerability of our forests.

Interdisciplinary approach to global challenges

What Sebastian Sippel and Ana Bastos have in common is not only their shared workplace at Leipzig University, but also their conviction that interdisciplinary approaches are crucial to tackling the challenges of climate change. Sebastian Sippel contributes his expertise in modelling and statistical analysis of extreme events, while Ana Bastos provides the biogeochemical perspective. The two colleagues also complement each other well on a personal level: while she describes herself as being full of energy but sometimes too impulsive, he is a good counterbalance who quickly brings her back down to earth.

Both scientists are part of an ambitious project within the proposed Breathing Nature Cluster of Excellence. This project aims to explore the complex interactions between biodiversity loss and climate change. “With its strong profile in earth system research, Leipzig University offers the ideal platform for researching these questions,” says Ana Bastos. For both researchers, one thing is certain: to develop effective climate change policies, we need to understand not only the effects of climate change on the environment, but also how human activities are altering these interactions.

Direct benefit to society

The work of Sebastian Sippel and Ana Bastos extends far beyond the academic world. It provides essential data and models that can be used to inform policy decisions and practical action. For example, their research findings are helping to strengthen the resilience of ecosystems by identifying factors that increase vulnerability to climate extremes. At the same time, they are improving forecasts of what can be expected in the future – and Sebastian Sippel is hopeful: “We may yet see a turning point in climate attribution research long in the future. Instead of analysing how much climate change has exacerbated an extreme event, studies could focus on which adaptation measures have mitigated the effects of such events.” Leipzig University will continue to do everything in its power to drive this change and actively steer research in a pioneering direction. This is the only way we can use the best scientific insights to meet the challenges of climate change.

Ana Bastos, who has been professor of land-atmosphere interactions at the Institute for Earth System Science and Remote Sensing at Leipzig University since 2024, completed her doctorate in geophysics and geoinformation sciences at the University of Lisbon in 2015. During her career, she has researched and taught in Portugal, the US, France, Munich and Jena. She was awarded an ERC Starting Grant in 2022 for research that focuses on the effects of climate extremes, particularly on forests. Besides researching and teaching, Ana Bastos is committed to promoting diversity and inclusion and improving mental health in academia.

Sebastian Sippel has been junior professor for climate attribution at the Institute for Meteorology at Leipzig University since 2023. Previously, he was a research assistant and postdoc at ETH Zurich, in Norway, and at the Max Planck Institute for Biogeochemistry in Jena. His research focuses on improving the understanding of climate variability, extreme events and their changes at global and regional scales. He uses empirical and quantitative statistical and machine learning techniques to address these research questions, integrating different climate and earth science data streams, such as climate observations and climate model simulations.

Created by: Dr. Katarina Werneburg / Translation: Matthew Rockey