EGU2020-2850, updated on 13 Mar 2024
EGU General Assembly 2020
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Microphysics of Antarctic precipitation in climate models : recent advances and challenges

Étienne Vignon1, Josué Gehring1, Simon P. Alexander2, Georgia Sotiropoulou3, Nikola Besic4, Nicolas Jullien1, Noémie Planat1, Jean-Baptiste Madeleine5, and Franziska Gerber6,7
Étienne Vignon et al.
  • 1École Polytechnique Fédérale de Lausanne, Laboratoire de Télédetection Environnementale, Lausanne, Switzerland (
  • 2Australian Antarctic Division, Hobart, Tasmania, Australia
  • 3Laboratory of Atmospheric Processes and their Impacts (LAPI), École Polytechnique Fédérale de Lausanne, Switzerland
  • 4Météo France, Toulouse, France
  • 5Laboratoire de Météorologie Dynamique / Sorbonne Université, Paris, France
  • 6CRYOS, École Polytechnique Fédérale de Lausanne, Switzerland
  • 7WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland

The current assessment of the Antarctic surface mass balance mostly relies on reanalysis products or climate model simulations. The ability of models to reproduce the precipitation field at the regional and continental scales not only depends on the simulation of the atmospheric dynamics over the Southern Ocean and of the advection of moisture towards the ice sheet, but also on the representation of the microphysical processes that govern the formation and growth of ice crystals and snowflakes. This presentation reviews recent studies to stress the importance and challenges of evaluating the precipitation microphysics over Antarctica in climate models. It also discusses how recent observational campaigns including ground-based remote-sensing instruments can help pinpoint key processes that should be represented in models. We then present tangible examples of evaluation and improvement of microphysical schemes in the Polar WRF model thanks to radar and lidar observations acquired near Dumont d’Urville and Mawson stations on the Antarctic coast. Particular attention is devoted to three processes : i) the sublimation of snowfall within the katabatic layer that considerably reduces the amount of precipitation that actually reaches the surface ; ii) the snowflake aggregation responsible for rapid depletion of crystals within clouds ; iii) the generation of supercooled liquid water in frontal clouds that leads to crystal/snowflake riming. Such studies, albeit preliminary, could pave the way for further evaluations of clouds and precipitation in climate models in different Antarctic contexts, especially in the cold and pristine atmosphere of the Plateau.

How to cite: Vignon, É., Gehring, J., Alexander, S. P., Sotiropoulou, G., Besic, N., Jullien, N., Planat, N., Madeleine, J.-B., and Gerber, F.: Microphysics of Antarctic precipitation in climate models : recent advances and challenges, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2850,, 2020.


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