From single storms to large-scale waves: a multi-year kilometer-scale global simulation
4 affiliations
- 1ETH Zurich (Zurich, Switzerland)
- 2Institute for Atmospheric and Climate Science, ETH Zürich, 8092 Zurich, Switzerland
- 3Center for Climate Systems Modeling (C2SM), ETH Zürich, Zurich, Switzerland
- 4Swiss National Supercomputing Centre (CSCS), ETH Zürich, Lugano, Switzerland
Abstract
Global kilometer-scale (km-scale) weather and climate models offer new opportunities to unify numerical weather prediction (NWP) and climate modeling by explicitly simulating convection and mesoscale circulations globally within a single modeling framework. We present results from the first multi-year (April 2020–March 2024) global atmosphere-land simulation using the GPU-refactored ICON model at a 2.5 km horizontal grid spacing and 120 vertical levels. The simulation uses NWP physics and observed sea-surface temperatures. We assess its performance against satellite, reanalysis, and in-situ observations using standard statistics and the MOAAP feature-tracking framework to evaluate a wide spectrum of atmospheric phenomena. ICON reproduces global temperature and precipitation patterns, including a realistic single Intertropical Convergence Zone and physically consistent diurnal precipitation cycles. However, ICON exhibits continental warm and dry biases during the warm season, 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. Mesoscale convective systems (MCSs) exhibit realistic spatial initiation patterns, but their frequency is underestimated over oceans and overestimated over tropical land. Long-lived MCSs are too infrequent and small, while excess rainfall from shallow and mid-level clouds suggests overactive warm-cloud microphysics. These biases likely stem in part from an underrepresentation of convectively coupled equatorial waves. Our results demonstrate the feasibility and scientific value of multi-year global convection-permitting simulations for exploring the weather–climate system and local-scale extreme events, while identifying key directions for future model development.
Related
- SD3: The First Operationally-Proven, Fully Heterogeneous-Accelerated Global Kilometer-Scale Model with Inline Physics Architecture
- Efficient Analog-Initialized Latent Transport for Spatially Coherent Probabilistic Downscaling from Global to Kilometer Scales
- SwAIther-Precip: Lead-Time-Aware Bias Correction Enables Kilometer-Scale Downscaling of Global AI Precipitation Forecasts over Switzerland
- Impact of F10.7 Flux and Proton Intensity on Delayed Ionospheric TEC Responses at Low Latitudes during Geomagnetic Storms across Solar Cycles 23–25
- Clear‐Air Turbulence Upstream of a Hydraulic Jump Leading to a Helicopter Accident—A Large Eddy Simulation
BibTeX
@article{prein2026from,
title = {{From single storms to large-scale waves: a multi-year kilometer-scale global simulation}},
author = {Andreas Franz Prein and Praveen Kumar Pothapakula and Christian Zeman and Morgane Lalonde and Marius Rixen and Anurag Dipankar and Matthieu Leclair and A. Jocksch},
journal = {Geoscientific model development},
year = {2026},
month = jun,
doi = {10.5194/gmd-19-5277-2026},
url = {https://doi.org/10.5194/gmd-19-5277-2026},
note = {CC BY},
}
RIS
TY - JOUR
TI - From single storms to large-scale waves: a multi-year kilometer-scale global simulation
AU - Andreas Franz Prein
AU - Praveen Kumar Pothapakula
AU - Christian Zeman
AU - Morgane Lalonde
AU - Marius Rixen
AU - Anurag Dipankar
AU - Matthieu Leclair
AU - A. Jocksch
PY - 2026
DA - 2026/06/19
JO - Geoscientific model development
DO - 10.5194/gmd-19-5277-2026
UR - https://doi.org/10.5194/gmd-19-5277-2026
AB - Global kilometer-scale (km-scale) weather and climate models offer new opportunities to unify numerical weather prediction (NWP) and climate modeling by explicitly simulating convection and mesoscale circulations globally within a single modeling framework. We present results from the first multi-year (April 2020–March 2024) global atmosphere-land simulation using the GPU-refactored ICON model at a 2.5 km horizontal grid spacing and 120 vertical levels. The simulation uses NWP physics and observed sea-surface temperatures. We assess its performance against satellite, reanalysis, and in-situ observations using standard statistics and the MOAAP feature-tracking framework to evaluate a wide spectrum of atmospheric phenomena. ICON reproduces global temperature and precipitation patterns, including a realistic single Intertropical Convergence Zone and physically consistent diurnal precipitation cycles. However, ICON exhibits continental warm and dry biases during the warm season, 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. Mesoscale convective systems (MCSs) exhibit realistic spatial initiation patterns, but their frequency is underestimated over oceans and overestimated over tropical land. Long-lived MCSs are too infrequent and small, while excess rainfall from shallow and mid-level clouds suggests overactive warm-cloud microphysics. These biases likely stem in part from an underrepresentation of convectively coupled equatorial waves. Our results demonstrate the feasibility and scientific value of multi-year global convection-permitting simulations for exploring the weather–climate system and local-scale extreme events, while identifying key directions for future model development.
SN - 1991-959X
SN - 1991-9603
ER -