Professorship for Physical Geography and Land-Atmosphere Coupling

Our Research: Land-Atmosphere Interactions and Their Role in Weather and Climate

Atmospheric turbulence and clouds interact in complex ways with soil moisture and vegetation. Through a range of feedback mechanisms, these interactions regulate the exchange of energy and water between the land surface and the atmosphere, shaping weather and climate near the Earth's surface. They also play a crucial role in the development and evolution of extreme weather and climate events, including heatwaves, heavy precipitation, and droughts. A better understanding of these processes is essential for improving weather forecasts and climate projections, reducing uncertainties in future climate predictions, and developing effective climate change adaptation strategies.

Our research group investigates how small-scale, rapidly evolving atmospheric processes, such as turbulence and shallow cumulus clouds, influence land-atmosphere interactions and feedbacks at regional scales. We are especially interested in the complex interplay between atmospheric processes, soil moisture, vegetation, and land use. Our research focuses on three main areas:

1. We develop and evaluate new approaches to represent micrometeorological processes and their interactions with the land surface more realistically in numerical weather and climate models.
2. We investigate how land-atmosphere interactions and feedbacks contribute to persistent biases in simulated temperature, humidity, and precipitation, and how improved representations of these processes can help reduce such biases.
3. We examine how changes in land use and land cover affect atmospheric turbulence, cumulus clouds, and surface energy and water budgets, while addressing the uncertainties associated with these impacts.

To address these research questions, we combine field observations with high-resolution numerical modeling of the coupled land-atmosphere system. A central tool in our research is large-eddy simulation (LES) in model configurations with realistic representations of land surface. These simulations explicitly resolve the dominant turbulent eddies and allow us to investigate atmospheric turbulence, convective clouds, and their interactions with heterogeneous land surfaces in detail. Particular attention is given to small-scale variations in soil moisture, vegetation, and topography.
By integrating observations and numerical simulations, we gain new insights into the physical processes governing interactions between the land surface and the atmosphere. We use this process-level understanding to improve the representation of land–atmosphere interactions in weather and climate models and to translate insights gained at small spatial and temporal scales into improvements at larger scales.
Our overarching goal is to advance the understanding of land-atmosphere interactions and contribute to more reliable weather forecasts and climate projections, particularly regarding extreme weather and climate events.

Research Highlights

• The Reflectance Distribution of Shallow Cumulus and Its Environs From High Spatial Resolution ASTER Images https://doi.org/10.1029/2025JD045060
• Where does numerical weather prediction meet large-eddy simulations? https://doi.org/10.1002/qj.70037
• In preparation for the VITAL II (2026) observational campaign: modeling the atmospheric boundary layer over urban-rural contrasts https://doi.org/10.5281/zenodo.17424651

• Transient darkening of low-level liquid clouds by the 2022 Hunga Lamb wave observed in GOES-R imagery, https://doi.org/10.1029/2025GL115935
  https://www.nature.com/articles/d41586-025-02019-6