RP 5: Statistics of Ice Nucleation Conditions in Mixed-Phase Clouds

Prof. Dr. Corinna Hoose

Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology


Assistance: Dr. Monika Niemand (Postcdoc), Dr. Luke Hande (Postdoc), Isabelle Reichardt (Doktorandin)



During INUIT Phase 1, RP5 focused on the transfer of novel laboratory-based ice nucleation parameterizations into a mesoscale model, their comparison to established parameterizations for case studies of orographic clouds, and the impact on the cloud properties.


The COSMO model has been extended by several state-of-the-art ice nucleation parameterizations (DeMott et al, 2010, 2014; Phillips et al, 2008, 2013; Niemand et al, 2012; Niedermeier et al, 2014) and a detailed comparison within the framework of idealized simulations of orographic clouds is currently being conducted. Furthermore, the model has been set up and run for a real case of the JFJ campaign during which a mixed-phase cloud was observed at the station. In addition RP5 has significantly contributed to several collaborative projects within INUIT. A comprehensive review of results of laboratory ice nucleation experiments was presented in Hoose and Möhler (2012) (collaboration of RP5 and RP7).



North-South-Cross-Section through the Alps at "Messtation Jungfraujoch" and and by COSMO-Modell calculated specific Wolkeneisgehalt (in kg kg-1 x 10-4) unter Verwendung der DeMott et al., 2010 Parametrisierung für den 9.02.2013, 2 UTC



During INUIT Phase 2, this research project will elucidate the frequency of occurrence of the various heterogeneous ice nucleation processes in different mixed-phase clouds regimes which commonly occur in Mid-Europe. Furthermore, we study the possibility of achieving INP closure for the INUIT-2 Mediterranean field campaign together with WP-F and WP-L.


The project will be organized in four tasks:

  • Update of the COSMO and later ICON-LES microphysics scheme by laboratory-based parameterizations of immersion, deposition and contact nucleation, tracking of in-droplet particles, and diagnostics
  • Selection and setup of idealized case studies of stratiform, convective and orographic
  • clouds representative for mixed-phase clouds in Europe
  • Analysis of the simulations with respect to the location and magnitude of different ice
  • nucleation processes
  • INP closure study


More information about this project:





DeMott, P. J., Prenni, A. J., Liu, X., Kreidenweis, S. M., Petters, M. D., Twohy, C. H., M. S.
Richardson, T. Eidhammer & Rogers, D. C. (2010). Predicting global atmospheric ice nuclei distributions and their impacts on climate. Proceedings of the National Academy of Sciences,107(25), 11217-11222.
Phillips, V. T., DeMott, P. J., & Andronache, C. (2008). An empirical parameterization of
heterogeneous ice nucleation for multiple chemical species of aerosol. Journal of the
Atmospheric Sciences, 65(9), 2757-2783.
Phillips, V. T., Demott, P. J., Andronache, C., Pratt, K. A., Prather, K. A., Subramanian, R., &
Twohy, C. (2013). Improvements to an empirical parameterization of heterogeneous ice
nucleation and its comparison with observations. Journal of the Atmospheric Sciences, 70(2),378-409.
Niemand, M., O. Möhler, B. Vogel, H. Vogel, C. Hoose, P. Connolly, H. Klein, H. Bingemer, P.
DeMott, J. Skrotzki and T. Leisner (2012): A particle-surface-area-based parameterization of immersion freezing on desert dust particles. Journal of the Atmospheric Sciences 69, 3077-3092.
Niedermeier, D., Ervens, B., Clauss, T., Voigtländer, J., Wex, H., Hartmann, S., & Stratmann, F. (2014). A computationally efficient description of heterogeneous freezing: A simplified version ofthe Soccer ball model. Geophysical Research Letters, 41(2), 736-741.
Hoose, C. and O. Möhler (2012): Heterogeneous ice nucleation on atmospheric aerosols: A review of results from laboratory experiments. Atmospheric Chemistry and Physics 12, 9817-9854, doi:10.5194/acp-12-9817-2012