Conesa et al. (2026) Dry snow initialization and densification over the Greenland and Antarctic ice sheets in the ORCHIDEE land surface model

Identification

• Journal: ˜The œcryosphere
• Year: 2026
• Date: 2026-09-03
• Authors: Sylvie Charbit
• DOI: 10.5194/tc-20-4973-2026

Research Groups

• Laboratoire des Sciences du Climat et de l'Environnement (LSCE), CEA, CNRS, UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
• Institut Pierre-Simon Laplace (IPSL), Université Versailles Saint-Quentin, Guyancourt, France
• European Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading, RG2 9AX, UK

Short Summary

This study aims to improve the representation of snow densification processes over Greenland and Antarctica in the ORCHIDEE land surface model. The authors develop a new initialization procedure for snowpacks, a wind-based surface snow density parameterization, and recalibrate the dry-snow densification scheme using observations and offline simulations.

Objective

• To evaluate and improve the capacity of the ORCHIDEE land surface model to represent snow densification processes over Greenland and Antarctica.
• To develop and test new methods for initializing the snowpack over polar regions.

Study Configuration

• Spatial Scale: Continental scale, focusing on Greenland and Antarctica ice sheets.
• Temporal Scale: Long-term simulations (1980-2019) with a 30-minute time step.

Methodology and Data

• Models used: ORCHIDEE land surface model, Explicit Snow module, MAR regional atmospheric model.
• Data sources: SUMup collaborative database, GLACIOCLIM-SAMBA dataset, ERA5 reanalysis.

Main Results

• The new initialization procedure improves the representation of snowpack density and temperature profiles over Greenland and Antarctica.
• The wind-based surface snow density parameterization shows good agreement with observations in both regions.
• The recalibrated dry-snow densification scheme reduces excessive compaction at depth and improves the overall representation of snow densification.

Contributions

• This study provides a significant improvement to the representation of snow densification processes over Greenland and Antarctica in the ORCHIDEE land surface model.
• The new initialization procedure and parameterizations can be applied to other snowpack models, improving their ability to simulate polar snow conditions.

Funding

• This research was supported by the European Centre for Medium-Range Weather Forecasts (ECMWF) and the French National Research Agency (ANR).

Citation

@article{Conesa2026Dry,
  author = {Conesa, Philippe and Agosta, Cécile and Charbit, Sylvie and Dumas, Christophe and Beylat, Simon and Raoult, Nina},
  title = {Dry snow initialization and densification over the Greenland and Antarctic ice sheets in the ORCHIDEE land surface model},
  journal = {˜The œcryosphere},
  year = {2026},
  doi = {10.5194/tc-20-4973-2026},
  url = {https://doi.org/10.5194/tc-20-4973-2026}
}