Prein et al. (2026) From single storms to large-scale waves: a multi-year kilometer-scale global simulation

Identification

• Journal: Geoscientific model development
• Year: 2026
• Date: 2026-06-19
• Authors: Andreas Franz Prein, Praveen Kumar Pothapakula, Christian Zeman, Morgane Lalonde, Marius Rixen, Anurag Dipankar, Matthieu Leclair, A. Jocksch
• DOI: 10.5194/gmd-19-5277-2026

Research Groups

• Institute for Atmospheric and Climate Science, ETH Zürich
• Center for Climate Systems Modeling (C2SM), ETH Zürich
• Swiss National Supercomputing Centre (CSCS), ETH Zürich

Short Summary

This study presents a multi-year kilometer-scale global simulation using the GPU-refactored ICON model at a 2.5 km horizontal grid spacing and 120 vertical levels, evaluating its performance against satellite, reanalysis, and in-situ observations.

Objective

• Evaluate the feasibility of multi-year global km-scale simulations for exploring the weather–climate system and local-scale extreme events.
• Assess the skill of the simulation in reproducing climate mean states and key mesoscale phenomena.
• Identify systematic model deficiencies that can inform future model development.

Study Configuration

• Spatial Scale: Global, with a horizontal grid spacing of 2.5 km.
• Temporal Scale: Four consecutive years (April 2020–March 2024).

Methodology and Data

• Models used: ICON model, GPU-refactored version.
• Data sources:
  • Satellite data: ERA5 reanalysis, NCEP/CPC Level-3 merged infrared T b dataset, NOAA outgoing longwave radiation (OLR) dataset.
  • Reanalysis data: ERA5 reanalysis.
  • In-situ observations: HadISD station observations, FLUXNET and AmeriFlux datasets.

Main Results

• The simulation reproduces global temperature and precipitation patterns, including a realistic single Intertropical Convergence Zone and physically consistent diurnal precipitation cycles.
• However, the model exhibits continental summertime warm and dry biases, linked to an overestimation of incoming solar radiation and excessive surface sensible heat fluxes.
• The model realistically captures the intensity and frequency of hourly precipitation and near-surface winds, as well as the structure and occurrence of tropical cyclones.

Contributions

• This study demonstrates the feasibility and scientific value of multi-year global km-scale simulations for exploring the weather–climate system and local-scale extreme events.
• The results highlight the importance of explicit treatment of convection and mesoscale storm systems in global models.

Funding

• Not specified.

Citation

@article{Prein2026From,
  author = {Prein, Andreas Franz and Pothapakula, Praveen Kumar and Zeman, Christian and Lalonde, Morgane and Rixen, Marius and Dipankar, Anurag and Leclair, Matthieu and Jocksch, A.},
  title = {From single storms to large-scale waves: a multi-year kilometer-scale global simulation},
  journal = {Geoscientific model development},
  year = {2026},
  doi = {10.5194/gmd-19-5277-2026},
  url = {https://doi.org/10.5194/gmd-19-5277-2026}
}