Articles | Volume 26, issue 4
https://doi.org/10.5194/acp-26-3125-2026
© 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/acp-26-3125-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Contrail formation for aircraft with hydrogen combustion – Part 1: A systematic microphysical investigation
Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
Simon Unterstrasser
Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
Ulrike Burkhardt
Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
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The climate impact of aviation-induced contrail cirrus clouds is strongly influenced by the number of ice crystals that form in the wake of an aircraft under certain conditions. In this study, we investigate how engine-related aspects influence the number of ice crystals formed for hydrogen combustion. We derive suitable (scaling) relations that can be integrated into large-scale models used to estimate the climate impact of contrail cirrus clouds.
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Using hydrogen as aviation fuel affects contrails' climate impact. We study contrail formation behind aircraft with H2 combustion. Due to the absence of soot emissions, contrail ice crystals are assumed to form only on ambient particles mixed into the plume. The ice crystal number, which strongly varies with temperature and aerosol number density, is decreased by more than 80 %–90 % compared to kerosene contrails. However H2 contrails can form at lower altitudes due to higher H2O emissions.
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Short summary
The climate impact of aviation-induced contrail cirrus is strongly influenced by the number of ice crystals that form in an aircraft's exhaust plume. In this study, we systematically investigate the key microphysical processes of contrail formation for hydrogen combustion. A large simulation data set provides the basis for a data-driven parameterization of ice crystal number that can be integrated into large-scale models.
The climate impact of aviation-induced contrail cirrus is strongly influenced by the number of...
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