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.
The project CAINA investigates how nitrogen compounds alter cloud microphysics. The project combines laboratory and field measurements with modeling.
CAINA-NAT provides, among others, new insights into turbulence-cloud interactions and defines the parameter space for our laboratory and numerical experiments
MINION enables measurements of atmospheric ice nucleating particles in a significantly wider temperature and concentration range than existing instrumentation.
The aim of MORIS is to better understand and quantify the secondary ice formation process “rime splintering”.
SEAL measures the moist sea spray aerosol above the water surface to systematically assess its damping effect on various light sources.
SCALE-TRACK is an algorithm for Euler-Lagrange simulations that scales efficiently on current exascale supercomputers and can enable cloud simulations with unprecedented accuracy, among other things.
TINIA investigates the influence of turbulence on ice crystal formation and diffusional growth on the example of stratiform mixed-phase clouds.
TURtle investigates one of the central questions in cloud physics: how does turbulence affect cloud droplet growth due to saturation fluctuations?