Project Details
Projekt
FRAGILE: Exploring the role of FRAGmentation of ice particles by combining super-partIcle modelling, Laborotary studies, and polarimEtric radar observations
Subject Area
Atmospheric Science
Term
since 2022
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 492234709
In the project FRAGILE spectral multi-frequency and polarimetric cloud radar observations will be combined with novel Lagrangian super-particle modelling, and laboratory studies to investigate ice microphysical processes in clouds. In agreement with previous studies, we find indications in polarimetric radar observations of new particle formation especially within the dendritic growth zone. Fragmentation of ice and snow particles has been debated for many years as potential candidate to explain those radar features but our current knowledge about this process is still very poor. In FRAGILE, we aim now to perform new laboratory experiments including collision experiments in a cold room and in a wind tunnel, to directly observe and quantify possible fragmentation of snowflakes or rimed particles. The results from the lab will be used to refine model parameterizations which will then be constrained by comparing the forward modelled radar signatures with our existing multi-months polarimetric cloud radar dataset of real clouds. Once a certain level of convergence is reached with the numerically expensive 1D Lagrangian super-particle model, we will apply machine learning methods to derive parameterizations for bulk schemes implemented in the ICON model. If fragmentation turns out to be a substantial source of small ice crystals, we expect that its implementation in models will provide significant improvements of our ability to simulate evolution of clouds and precipitation.
DFG Programme
Priority Programmes
