“The mission of our team is to study cloud microphysical processes in laminar and turbulent environments to better understand the behavior of warm and mixed-phase clouds. The processes of interest include the formation, growth and decay of cloud droplets and ice crystals (with one specific focus on primary and secondary ice formation), as well as cloud mixing at interfacial layers. To achieve our goals, we conduct innovative research comprising cutting-edge laboratory and field studies, as well as process-scale modeling. We grant access to our unique research infrastructures to facilitate collaborative research. Ultimately, we provide the atmospheric science community with the knowledge it needs to build more accurate models and address critical challenges in a changing climate.”

The “Fundamental Cloud Microphysics” team, led by Dr. Dennis Niedermeier, focuses on the investigation of microphysical processes in clouds and their interactions with turbulence, aerosols, and thermodynamic conditions. The main focus is on warm clouds (T > 0 °C) as well as mixed-phase clouds, which occur between 0 °C and −38 °C and are characterized by the simultaneous presence of supercooled water droplets and ice crystals.

One research topic is the understanding of ice formation processes in clouds. In addition to primary ice nucleation by specific aerosol particles (ice-nucleating particles, INPs), secondary ice production (SIP) mechanisms are investigated, which lead to the multiplication of ice particles in clouds. Another key focus is the role of turbulence in clouds. The team investigates how turbulent fluctuations in temperature and humidity influence numerous microphysical processes, such as the formation and growth of cloud droplets, as well as the freezing of supercooled cloud droplets into ice crystals and their subsequent growth. Furthermore, the effects of turbulent mixing processes at interfaces and boundary layers are investigated. This includes, among others, entrainment and detrainment processes, where entrainment describes the mixing of cloud-free air into the cloud, and detrainment the mixing of cloudy air into the surrounding environment.

Overall, the investigations, which are conducted in the laboratory and in the field as well as carried out through numerical simulations, contribute to improving the understanding of cloud formation and development and thus provide important insights into cloud lifetime and precipitation formation.