Articles | Volume 25, issue 23
https://doi.org/10.5194/acp-25-17253-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-17253-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Dec 2025
Research article |
| 01 Dec 2025
| 01 Dec 2025
Predicting ice supersaturation for contrail avoidance: ensemble forecasting using ICON with two-moment ice microphysics
Deutscher Wetterdienst, Frankfurter Straße 135, 63067 Offenbach am Main, Germany
Carmen G. Köhler
Deutscher Wetterdienst, Frankfurter Straße 135, 63067 Offenbach am Main, Germany
Axel Seifert
Deutscher Wetterdienst, Frankfurter Straße 135, 63067 Offenbach am Main, Germany
Linda Schlemmer
Deutscher Wetterdienst, Frankfurter Straße 135, 63067 Offenbach am Main, Germany
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Atmos. Chem. Phys., 25, 4505–4529, https://doi.org/10.5194/acp-25-4505-2025, https://doi.org/10.5194/acp-25-4505-2025, 2025
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Axel Seifert, Vanessa Bachmann, Florian Filipitsch, Jochen Förstner, Christian M. Grams, Gholam Ali Hoshyaripour, Julian Quinting, Anika Rohde, Heike Vogel, Annette Wagner, and Bernhard Vogel
Atmos. Chem. Phys., 23, 6409–6430, https://doi.org/10.5194/acp-23-6409-2023, https://doi.org/10.5194/acp-23-6409-2023, 2023
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We investigate how mineral dust can lead to the formation of cirrus clouds. Dusty cirrus clouds lead to a reduction in solar radiation at the surface and, hence, a reduced photovoltaic power generation. Current weather prediction systems are not able to predict this interaction between mineral dust and cirrus clouds. We have developed a new physical description of the formation of dusty cirrus clouds. Overall we can show a considerable improvement in the forecast quality of clouds and radiation.
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Markus Karrer, Axel Seifert, Davide Ori, and Stefan Kneifel
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Modeling precipitation is of great relevance, e.g., for mitigating damage caused by extreme weather. A key component in accurate precipitation modeling is aggregation, i.e., sticking together of snowflakes. Simulating aggregation is difficult due to multiple parameters that are not well-known. Knowing how these parameters affect aggregation can help its simulation. We put new parameters in the model and select a combination of parameters with which the model can simulate observations better.
Daniel Regenass, Linda Schlemmer, Elena Jahr, and Christoph Schär
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2021-426, https://doi.org/10.5194/hess-2021-426, 2021
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A new integrated mass-flux adjustment filter is introduced and examined with an idealized setup for convective-scale radar data assimilation. It is found that the new filter slightly reduces the accuracy of background and analysis states; however, it preserves the main structure of cold pools and primary mesocyclone properties of supercells. More importantly, it successfully diminishes the imbalance in the analysis considerably and improves the forecasts.
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Short summary
Persistent condensation trails typically occur due to aircraft flying through certain cold and humid regions. In most cases, these contrails have a warming impact on the climate. Predicting these regions in advance allows flight planners to re-route airplanes. We show that an adaptation of the ice microphysics scheme in a certain weather forecast model improves the prediction of these regions. Running an ensemble of simulations with this scheme improves the prediction quality even further.
Persistent condensation trails typically occur due to aircraft flying through certain cold and...
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