Articles | Volume 19, issue 12
https://doi.org/10.5194/gmd-19-5531-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-19-5531-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Development and technical paper
| 
26 Jun 2026
Development and technical paper |
| 26 Jun 2026
| 26 Jun 2026
A systematic atmospheric parameter optimization method to improve ENSO simulation in the ICON XPP Earth system model
Max Planck Institute for Meteorology, Hamburg, Germany
Dietmar Dommenget
ARC Centre of Excellence for Climate Extremes, School of Earth, Atmosphere and Environment, Monash University, Clayton, Victoria, Australia
Holger Pohlmann
Max Planck Institute for Meteorology, Hamburg, Germany
Wolfgang A. Müller
Max Planck Institute for Meteorology, Hamburg, Germany
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Wolfgang A. Müller, Stephan Lorenz, Trang V. Pham, Andrea Schneidereit, Renate Brokopf, Victor Brovkin, Nils Brüggemann, Fatemeh Chegini, Dietmar Dommenget, Kristina Fröhlich, Barbara Früh, Veronika Gayler, Helmuth Haak, Stefan Hagemann, Moritz Hanke, Tatiana Ilyina, Johann Jungclaus, Martin Köhler, Peter Korn, Luis Kornblueh, Clarissa A. Kroll, Julian Krüger, Karel Castro-Morales, Ulrike Niemeier, Holger Pohlmann, Iuliia Polkova, Roland Potthast, Thomas Riddick, Manuel Schlund, Tobias Stacke, Roland Wirth, Dakuan Yu, and Jochem Marotzke
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We provide a new Earth System model configuration framed into the ICON architecture, which provides the baseline for the next generation of climate predictions and projections (hereafter ICON XPP). Two resolutions of ICON XPP are presented that show high runtime performances making it suitable to run long integrations and large-ensemble experiments. ICON XPP similarly perform to CMIP6-class of climate models making it a good basis for climate forecasts and projections, and climate research.
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This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
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ICONEval is a new framework to facilitate researchers to continuously monitor and check their climate models during the development phase. It builds on the ESMValTool software package to run tests verifying that the results are plausible, follow physical laws, and that the model has sufficient skill in reproducing the observed climate. An important aim is to make it easier to spot model errors early, for example when implementing new model components that use machine learning.
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EGUsphere, https://doi.org/10.5194/egusphere-2026-126, https://doi.org/10.5194/egusphere-2026-126, 2026
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The SOLCHECK project studied how fluctuations in the Sun’s energy output affect weather and climate. Strong solar storms deplete ozone and raise ultraviolet irradiance, the impact of the 11-year solar cycle depends on stratospheric dynamics, and long-term Grand Solar Minima leave fingerprints in past and future climate states. The large model ensemble explored in SOLCHECK helped to separate the various solar effects from human-driven change and improved our understanding of climate feedbacks.
Ned C. Williams, Wolfgang A. Müller, and Joaquim G. Pinto
EGUsphere, https://doi.org/10.5194/egusphere-2025-6330, https://doi.org/10.5194/egusphere-2025-6330, 2026
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Decadal forecasts use models to predict near-term natural and human-induced climate changes. Large scale pressure patterns affect surface impacts, but in summer they are hard to predict. North Atlantic surface temperatures are known to influence these patterns in summer. We find that a large set of retrospective decadal forecasts can predict this ocean-atmosphere interaction but also underestimates it, consistent with other predictable North Atlantic pressure patterns in climate forecasts.
Wolfgang A. Müller, Stephan Lorenz, Trang V. Pham, Andrea Schneidereit, Renate Brokopf, Victor Brovkin, Nils Brüggemann, Fatemeh Chegini, Dietmar Dommenget, Kristina Fröhlich, Barbara Früh, Veronika Gayler, Helmuth Haak, Stefan Hagemann, Moritz Hanke, Tatiana Ilyina, Johann Jungclaus, Martin Köhler, Peter Korn, Luis Kornblueh, Clarissa A. Kroll, Julian Krüger, Karel Castro-Morales, Ulrike Niemeier, Holger Pohlmann, Iuliia Polkova, Roland Potthast, Thomas Riddick, Manuel Schlund, Tobias Stacke, Roland Wirth, Dakuan Yu, and Jochem Marotzke
Geosci. Model Dev., 18, 9385–9415, https://doi.org/10.5194/gmd-18-9385-2025, https://doi.org/10.5194/gmd-18-9385-2025, 2025
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We provide a new Earth System model configuration framed into the ICON architecture, which provides the baseline for the next generation of climate predictions and projections (hereafter ICON XPP). Two resolutions of ICON XPP are presented that show high runtime performances making it suitable to run long integrations and large-ensemble experiments. ICON XPP similarly perform to CMIP6-class of climate models making it a good basis for climate forecasts and projections, and climate research.
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Tropical ocean basins influence each other through multiple pathways and mechanisms, referred to here as tropical basin interaction (TBI). Many researchers have examined TBI using comprehensive climate models but have obtained conflicting results. This may be partly due to differences in experiment protocols and partly due to systematic model errors. The Tropical Basin Interaction Model Intercomparison Project (TBIMIP) aims to address this problem by designing a set of TBI experiments that will be performed by multiple models.
Wenjuan Huo, Tobias Spiegl, Sebastian Wahl, Katja Matthes, Ulrike Langematz, Holger Pohlmann, and Jürgen Kröger
Atmos. Chem. Phys., 25, 2589–2612, https://doi.org/10.5194/acp-25-2589-2025, https://doi.org/10.5194/acp-25-2589-2025, 2025
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Uncertainties of the solar signals in the middle atmosphere are assessed based on large ensemble simulations with multiple climate models. Our results demonstrate that the 11-year solar signals in the shortwave heating rate, temperature, and ozone anomalies are significant and robust. The simulated dynamical responses are model-dependent, and solar imprints in the polar night jet are influenced by biases in the model used.
Lara Wallberg, Laura Suarez-Gutierrez, Daniela Matei, and Wolfgang A. Müller
Earth Syst. Dynam., 15, 1–14, https://doi.org/10.5194/esd-15-1-2024, https://doi.org/10.5194/esd-15-1-2024, 2024
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European summer temperatures are influenced by mechanisms on different timescales. We find that timescales of 5 to 10 years dominate the changes in summer temperature over large parts of the continent. Further, we find that specific processes within the North Atlantic, affecting the storage and transport of heat, cause changes in the atmosphere and extremely warm European summers. Our findings could be used for better forecasts of extremely warm European summers several years ahead.
Tobias C. Spiegl, Ulrike Langematz, Holger Pohlmann, and Jürgen Kröger
Weather Clim. Dynam., 4, 789–807, https://doi.org/10.5194/wcd-4-789-2023, https://doi.org/10.5194/wcd-4-789-2023, 2023
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We investigate the role of the solar cycle in atmospheric domains with the Max Plank Institute Earth System Model in high resolution (MPI-ESM-HR). We focus on the tropical upper stratosphere, Northern Hemisphere (NH) winter dynamics and potential surface imprints. We found robust solar signals at the tropical stratopause and a weak dynamical response in the NH during winter. However, we cannot confirm the importance of the 11-year solar cycle for decadal variability in the troposphere.
Zhiang Xie and Dietmar Dommenget
EGUsphere, https://doi.org/10.5194/egusphere-2023-370, https://doi.org/10.5194/egusphere-2023-370, 2023
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Using numeric modelling, the global interaction between the climate system and ice sheets are examined in this study. The results show the existence of ice sheets slows the response of the climate system to external forcings and enhances the response in high latitude in Northern Hemisphere. Some interactions amplify the climate response, such as the ice-albedo, ice latent heat and topography feedbacks, while others damp or shift the climate response, such as snowfall and sea level feedbacks.
Zhiang Xie, Dietmar Dommenget, Felicity S. McCormack, and Andrew N. Mackintosh
Geosci. Model Dev., 15, 3691–3719, https://doi.org/10.5194/gmd-15-3691-2022, https://doi.org/10.5194/gmd-15-3691-2022, 2022
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Paleoclimate research requires better numerical model tools to explore interactions among the cryosphere, atmosphere, ocean and land surface. To explore those interactions, this study offers a tool, the GREB-ISM, which can be run for 2 million model years within 1 month on a personal computer. A series of experiments show that the GREB-ISM is able to reproduce the modern ice sheet distribution as well as classic climate oscillation features under paleoclimate conditions.
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Short summary
We developed a new method to improve how a leading climate model simulates El Niño, a major driver of global weather extremes. By testing how the model responds to small changes in key atmospheric settings, we identified which processes matter most and adjusted them systematically. This approach makes the model’s behavior closer to observations and shows a promising path for building more reliable climate predictions.
We developed a new method to improve how a leading climate model simulates El Niño, a major...
