Independent research, institutional impact

Part of the Max Planck Society's recipe for success is its person-centered research organization: Brilliant minds choose their topics freely and independently and gather excellent colleagues around them to bring their ideas and projects to success. In addition to the directors, the holders of so-called W2 positions also enjoy comprehensive scientific independence. Some of these positions supplement or strengthen an existing research program initiated by a director. Other positions, such as those awarded through the Lise Meitner Excellence Program, are entirely independent and allow for the development of new fields of research and the expansion of an institute's scientific profile. W2 positions are awarded by the president of the Max Planck Society (MPG) based on a rigorous external review and filled by exceptional scientists who have obtained a habilitation or equivalent qualification. The description “W2” stems from the employment relationship that matches those of civil servants in the same category.
At the MPI-M, the three departments—Climate Dynamics, Climate Physics, and Climate Variability—are headed by Directors Sarah Kang, Bjorn Stevens, and Jochem Marotzke. Each department has one group leader with a W2 position: Victor Brovkin, Cathy Hohenegger, and Jin-Song von Storch. Franziska Glassmeier, head of an independent Lise Meitner research group, holds the institute's fourth W2 position.
In addition to pursuing their own research program, the W2 group leaders are involved in internal institute policy. They are invited to participate in section meetings within the MPG and in extended directorate meetings, where important strategic decisions for the MPI-M are made.
Victor Brovkin: Climate-Biosphere Interaction

Victor Brovkin joined MPI-M in 2008. Initially he worked in the department “The Land in the Earth System” led by Martin Claussen, MPI-M Director at the time, with whom he had previously worked at the Potsdam Institute for Climate Impact Research. “We shared an interest in modeling the biosphere,” says Brovkin. His research prioritized the carbon cycle, initially of wetlands and later of permafrost.
Following Claussen’s retirement, Brovkin's group joined Sarah Kang's “Climate Dynamics” department in 2023 gaining more autonomy in terms of content. "Naturally, I try to contribute to the department's research goals, but I am fortunate to generally have freedom in the choice of my topics." Brovkin always tries to anticipate major new topics and address them early on. As a result, his work remains multifaceted after 17 years at the institute. Currently, the mathematician is working on two major themes: tipping elements in the Earth system and exploring the potential of data-driven science, which uses large data sets to test hypotheses. “Our models often fail to reproduce the observed non-linear dynamics, and I am trying to understand why." With the help of data science, Brovkin wants to develop models that are suitable for abrupt changes, for example in thawing permafrost landscapes, known as thermokarst.
Franziska Glassmeier: Multiscale Cloud Physics

Big data sets also play an important role in the research of Franziska Glassmeier, head of the Lise Meitner Research Group “Multiscale Cloud Physics” since June 2025. She uses data both from satellites and from high-resolution models to investigate the emergent properties of clouds. In this way, she aims to remedy a shortcoming of current climate models, which are based on the assumption that the individual cloud and the large-scale circulation to which it belongs can be separated. Her research focuses on the self-organization of clouds on the mesoscale, i.e. the spatial scale ranging from a few kilometers to hundreds of kilometers.
"The MPI-M is one of the best places worldwide for conceptual work," says Glassmeier. "Here, I can pursue the questions I want to address with the greatest possible scientific freedom." As part of the Lise Meitner Excellence Program, Glassmeier's group works independently of the institute's three departments. However, there are natural links, for example with the work done in the “Climate Physics” department, which performs cloud observations and develops climate models with a resolution of a few kilometers, among other things. "I expect that we will support and inspire each other, and I hope to contribute my scientific perspective to the discussions."
Cathy Hohenegger: Climate-surface interaction

Cathy Hohenegger is a W2 group leader in the “Climate Physics” department. She studies convection and precipitation in the Earth's atmosphere, as well as the role of the land and ocean surfaces in these processes. "Thunderstorms occur locally, which is why I initially focused on regional phenomena," says Hohenegger, who has been a researcher at the MPI-M for 15 years. She has recently been pushing the development of comprehensive Earth system modeling on a kilometer scale at the institute. "This allows us to place such regional processes in a global context—which can generate entirely new insights."
For example, Hohenegger and her doctoral researcher Arim Yoon recently showed that the average precipitation in the Amazon would not decrease significantly even if it were completely deforested, because the large-scale atmospheric circulation carries extra moisture into the region, compensating for the loss of in-situ moisture after deforestation. This was not predicted by traditional models and gives an idea of the significant progress in climate research made possible by global models that resolve processes on the kilometer scale. Hohenegger plays a key role in further developing these models at the MPI-M. She believes it is important to contribute her ideas to various committees at the institute: "I want to attract good people to the institute and help providing a thriving research environment, which is why I enjoy providing strategic impetus."
Jin-Song von Storch: Climate Energetics

Jin-Song von Storch has been a group leader and deputy director of the department "The Ocean in the Earth System," now "Climate Variability," for 21 years. When she started her position in 2004, she initially studied the role of randomness in the climate system, building on Klaus Hasselmann's pioneering work. Until then, randomness had mainly been considered in the context of the atmosphere. "For a long time, the ocean tended to be seen as rather deterministic," says von Storch. However, just as weather is part of the atmosphere, small-scale turbulence is part of the ocean—and this "ocean weather" interested her.
In recent years, advances in high-resolution climate modeling have provided von Storch with a new tool for studying waves and eddies, especially in terms of how they distribute energy in the climate system. The meteorologist is currently involved in the European Eddy-rich Earth System Models (EERIE) project, which is advancing high-resolution ocean modeling. “Perhaps my interests are rather niche,” says von Storch. “But that's the great thing about basic research: you don't always have to follow the mainstream.”
Jin-Song von Storch in Breaking the Surface, special exhibition of the International Maritime Museum Hamburg.
Contact
Prof. Dr. Victor Brovkin
Max Planck Institute for Meteorology
victor.brovkin@ mpimet.mpg.de
Dr. Franziska Glassmeier
Max Planck Institute for Meteorology
franziska.glassmeier@ mpimet.mpg.de
Dr. Cathy Hohenegger
Max Planck Institute for Meteorology
cathy.hohenegger@ mpimet.mpg.de
Prof. Dr. Jin-Song von Storch
Max Planck Institute for Meteorology
jin-song.von.storch@ mpimet.mpg.de