Articles | Volume 25, issue 14
https://doi.org/10.5194/acp-25-7903-2025
© 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-25-7903-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 Jul 2025
Research article |
| 25 Jul 2025
| 25 Jul 2025
High-resolution modeling of early contrail evolution from hydrogen-powered aircraft
Annemarie Lottermoser
CORRESPONDING AUTHOR
Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft- und Raumfahrt, Oberpfaffenhofen, Germany
Simon Unterstrasser
Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft- und Raumfahrt, Oberpfaffenhofen, Germany
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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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Cited articles
Airbus: Towards the world's first hydrogen-powered commercial aircraft, https://www.airbus.com/en/innovation/energy-transition/hydrogen/zeroe#concepts (last access: 27 October 2024), 2020. a
Airbus: Contrail-chasing Blue Condor makes Airbus' first full hydrogen-powered flight, https://www.airbus.com/en/newsroom/stories/2023-11-contrail-chasing-blue-condor-makes-airbus-first-full-hydrogen-powered# (last access: 15 November 2024), 2023. a
Bier, A., Burkhardt, U., and Bock, L.: Synoptic Control of Contrail Cirrus Life Cycles and Their Modification Due to Reduced Soot Number Emissions, J. Geophys. Res., 122, 11584–11603, https://doi.org/10.1002/2017JD027011, 2017. a
Bier, A., Unterstrasser, S., Zink, J., Hillenbrand, D., Jurkat-Witschas, T., and Lottermoser, A.: Contrail formation on ambient aerosol particles for aircraft with hydrogen combustion: a box model trajectory study, Atmos. Chem. Phys., 24, 2319–2344, https://doi.org/10.5194/acp-24-2319-2024, 2024. a, b, c, d, e, f, g, h, i, j, k, l
Bräuer, T., Voigt, C., Sauer, D., Kaufmann, S., Hahn, V., Scheibe, M., Schlager, H., Huber, F., Le Clercq, P., Moore, R. H., and Anderson, B. E.: Reduced ice number concentrations in contrails from low-aromatic biofuel blends, Atmos. Chem. Phys., 21, 16817–16826, https://doi.org/10.5194/acp-21-16817-2021, 2021. a
Burkhardt, U. and Kärcher, B.: Global radiative forcing from contrail cirrus, Nat. Clim. Change., 1, 54–58, https://doi.org/10.1038/nclimate1068, 2011. a
Burkhardt, U., Bock, L., and Bier, A.: Mitigating the contrail cirrus climate impact by reducing aircraft soot number emissions, npj Climate and Atmospheric Science, 1, 37, https://doi.org/10.1038/s41612-018-0046-4, 2018. a, b, c
Clark, T. L. and Farley, R. D.: Severe downslope windstorm calculations in two and three spatial dimensions using anelastic interactive grid nesting: a possible mechanism for gustiness, J. Atmos. Sci., 41, 329–350, 1984. a
Gierens, K.: Theory of Contrail Formation for Fuel Cells, Aerospace, 8, 164, https://doi.org/10.3390/aerospace8060164, 2021. a
Gierens, K. and Spichtinger, P.: On the size distribution of ice-supersaturated regions in the upper troposphere and lowermost stratosphere, Ann. Geophys., 18, 499–504, https://doi.org/10.1007/s00585-000-0499-7, 2000. a
Gierens, K., Matthes, S., and Rohs, S.: How Well Can Persistent Contrails Be Predicted?, Aerospace, 7, 169, https://doi.org/10.3390/aerospace7120169, 2020. a
Gruber, S., Unterstrasser, S., Bechtold, J., Vogel, H., Jung, M., Pak, H., and Vogel, B.: Contrails and their impact on shortwave radiation and photovoltaic power production – a regional model study, Atmos. Chem. Phys., 18, 6393–6411, https://doi.org/10.5194/acp-18-6393-2018, 2018. a
Huebsch, W. and Lewellen, D.: Sensitivity Study on Contrail Evolution, 36 th AIAA Fluid Dynamics Conference and Exhibit, AIAA 2006-3749, 1–14, https://doi.org/10.2514/6.2006-3749, 2006. a
Jansen, J. and Heymsfield, A. J.: Microphysics of Aerodynamic Contrail Formation Processes, J. Atmos. Sci., 72, 3293–3308, https://doi.org/10.1175/JAS-D-14-0362.1, 2015. a
Kärcher, B.: Formation and radiative forcing of contrail cirrus, Nat. Commun., 9, 1824, https://doi.org/10.1038/s41467-018-04068-0, 2018. a
Kärcher, B., Burkhardt, U., Bier, A., Bock, L., and Ford, I. J.: The microphysical pathway to contrail formation, J. Geophys. Res., 120, 7893–7927, https://doi.org/10.1002/2015JD023491, 2015. a, b, c, d
Kaufmann, S., Dischl, R., and Voigt, C.: Regional and seasonal impact of hydrogen propulsion systems on potential contrail cirrus cover, Atmos. Environ., 24, 100298, https://doi.org/10.1016/j.aeaoa.2024.100298, 2024. a
Kazula, S., de Graaf, S., and Enghardt, L.: Review of fuel cell technologies and evaluation of their potential and challenges for electrified propulsion systems in commercial aviation, Journal of the Global Power and Propulsion Society, 7, 43–57, https://doi.org/10.33737/jgpps/158036, 2023. a
Lee, D. S., Fahey, D. W., Skowron, A., Allen, M. R., Burkhardt, U., Chen, Q., Doherty, S. J., Freeman, S., Forster, P. M., Fuglestvedt, J., Gettelman, A., De León, R. R., Lim, L. L., Lund, M. T., Millar, R. J., Owen, B., Penner, J. E., Pitari, G., Prather, M. J., Sausen, R., and Wilcox, L. J.: The contribution of global aviation to anthropogenic climate forcing for 2000 to 2018, Atmos. Environ., 244, 117834, https://doi.org/10.1016/j.atmosenv.2020.117834, 2021. a
Lee, D. S., Allen, M. R., Cumpsty, N., Owen, B., Shine, K. P., and Skowron, A.: Uncertainties in mitigating aviation non-CO2 emissions for climate and air quality using hydrocarbon fuels, Environ. Sci.: Atmos., 3, 1693–1740, https://doi.org/10.1039/D3EA00091E, 2023. a
Lewellen, D. and Lewellen, W.: Large-eddy simulations of the vortex-pair breakup in aircraft wakes, AIAA Journal, 34, 2337–2345, 1996. a
Lewellen, D. C.: Persistent contrails and contrail cirrus. Part 2: Full Lifetime Behavior, J. Atmos. Sci., 71, 4420–4438, https://doi.org/10.1175/JAS-D-13-0317.1, 2014. a, b
Marciello, V., Di Stasio, M., Ruocco, M., Trifari, V., Nicolosi, F., Meindl, M., Lemoine, B., and Caliandro, P.: Design Exploration for Sustainable Regional Hybrid-Electric Aircraft: A Study Based on Technology Forecasts, Aerospace, 10, 165, https://doi.org/10.3390/aerospace10020165, 2023. a
Märkl, R. S., Voigt, C., Sauer, D., Dischl, R. K., Kaufmann, S., Harlaß, T., Hahn, V., Roiger, A., Weiß-Rehm, C., Burkhardt, U., Schumann, U., Marsing, A., Scheibe, M., Dörnbrack, A., Renard, C., Gauthier, M., Swann, P., Madden, P., Luff, D., Sallinen, R., Schripp, T., and Le Clercq, P.: Powering aircraft with 100 % sustainable aviation fuel reduces ice crystals in contrails, Atmos. Chem. Phys., 24, 3813–3837, https://doi.org/10.5194/acp-24-3813-2024, 2024. a
Marks, T., Dahlmann, K., Grewe, V., Gollnick, V., Linke, F., Matthes, S., Stumpf, E., Swaid, M., Unterstrasser, S., Yamashita, H., and Zumegen, C.: Climate Impact Mitigation Potential of Formation Flight, Aerospace, 8, 14, https://doi.org/10.3390/aerospace8010014, 2021. a
Moore, R. H., Thornhill, K. L., Weinzierl, B., Sauer, D., D'Ascoli, E., Kim, J., Lichtenstern, M., Scheibe, M., Beaton, B., Beyersdorf, A. J., Barrick, J., Bulzan, D., Corr, C. A., Crosbie, E., Jurkat, T., Martin, R., Riddick, D., Shook, M., Slover, G., Voigt, C., White, R., Winstead, E., Yasky, R., Ziemba, L. D., Brown, A., Schlager, H., and Anderson, B. E.: Biofuel blending reduces particle emissions from aircraft engines at cruise conditions, Nature, 543, 411–415, https://doi.org/10.1038/nature21420, 2017. a
Petzold, A., Kramer, M., Neis, P., Rolf, C., Rohs, S., Berkes, F., Smit, H. G. J., Gallagher, M., Beswick, K., Lloyd, G., Baumgardner, D., Spichtinger, P., Nedelec, P., Ebert, V., Buchholz, B., Riese, M., and Wahner, A.: Upper tropospheric water vapour and its interaction with cirrus clouds as seen from IAGOS long-term routine in situ observations, Faraday Discuss., 200, 229–249, https://doi.org/10.1039/C7FD00006E, 2017. a
Picot, J., Paoli, R., Thouron, O., and Cariolle, D.: Large-eddy simulation of contrail evolution in the vortex phase and its interaction with atmospheric turbulence, Atmos. Chem. Phys., 15, 7369–7389, https://doi.org/10.5194/acp-15-7369-2015, 2015. a
Ponsonby, J., King, L., Murray, B. J., and Stettler, M. E. J.: Jet aircraft lubrication oil droplets as contrail ice-forming particles, Atmos. Chem. Phys., 24, 2045–2058, https://doi.org/10.5194/acp-24-2045-2024, 2024. a, b
Prusa, J., Smolarkiewicz, P., and Wyszogrodzki, A.: EULAG, a computational model for multiscale flows, Comput. Fluids, 37, 1193–1207, https://doi.org/10.1016/j.compfluid.2007.12.001, 2008. a
Schumann, U., Mayer, B., Gierens, K., Unterstrasser, S., Jessberger, P., Petzold, A., Voigt, C., and Gayet, J.-F.: Effective Radius of Ice Particles in Cirrus and Contrails, J. Atmos. Sci., 68, 300–321, https://doi.org/10.1175/2010JAS3562.1, 2011. a
Smolarkiewicz, P. and Margolin, L.: On forward-in-time differencing for fluids: an Eulerian/semi-Lagrangian non-hydrostatic model for stratified flows, Atmosphere-Ocean Special, 35, 127–152, 1997. a
Sölch, I. and Kärcher, B.: A large-eddy model for cirrus clouds with explicit aerosol and ice microphysics and Lagrangian ice particle tracking, Q. J. Roy. Meteor. Soc., 136, 2074–2093, https://doi.org/10.1002/qj.689, 2010. a, b
Tiwari, S., Pekris, M. J., and Doherty, J. J.: A review of liquid hydrogen aircraft and propulsion technologies, Int. J. Hydrogen Energ., 57, 1174–1196, https://doi.org/10.1016/j.ijhydene.2023.12.263, 2024. a
Ungeheuer, F., van Pinxteren, D., and Vogel, A. L.: Identification and source attribution of organic compounds in ultrafine particles near Frankfurt International Airport, Atmos. Chem. Phys., 21, 3763–3775, https://doi.org/10.5194/acp-21-3763-2021, 2021. a
Ungeheuer, F., Caudillo, L., Ditas, F., Simon, M., van Pinxteren, D., Kilic, D., Rose, D., Jacobi, S., Kürten, A., Curtius, J., and Vogel, A. L.: Nucleation of jet engine oil vapours is a large source of aviation-related ultrafine particles, Commun. Earth Environ., 3, 1–8, https://doi.org/10.1038/s43247-022-00653-w, 2022. a, b
Unterstrasser, S.: The Contrail Mitigation Potential of Aircraft Formation Flight Derived from High-Resolution Simulations, Aerospace, 7, 170, https://doi.org/10.3390/aerospace7120170, 2020. a, b, c
Unterstrasser, S. and Gierens, K.: Numerical simulations of contrail-to-cirrus transition – Part 2: Impact of initial ice crystal number, radiation, stratification, secondary nucleation and layer depth, Atmos. Chem. Phys., 10, 2037–2051, https://doi.org/10.5194/acp-10-2037-2010, 2010. a
Unterstrasser, S. and Stephan, A.: Far field wake vortex evolution of two aircraft formation flight and implications on young contrails, Aeronaut. J., 124, 667–702, https://doi.org/10.1017/aer.2020.3, 2020. a
Unterstrasser, S., Paoli, R., Sölch, I., Kühnlein, C., and Gerz, T.: Dimension of aircraft exhaust plumes at cruise conditions: effect of wake vortices, Atmos. Chem. Phys., 14, 2713–2733, https://doi.org/10.5194/acp-14-2713-2014, 2014. a, b
Unterstrasser, S., Gierens, K., Sölch, I., and Lainer, M.: Numerical simulations of homogeneously nucleated natural cirrus and contrail-cirrus. Part 1: How different are they?, Meteorol. Z., 26, 621–642, https://doi.org/10.1127/metz/2016/0777, 2017a. a, b, c, d
Unterstrasser, S., Gierens, K., Sölch, I., and Wirth, M.: Numerical simulations of homogeneously nucleated natural cirrus and contrail-cirrus. Part 2: Interaction on local scale, Meteorol. Z., 26, 643–661, https://doi.org/10.1127/metz/2016/0780, 2017b. a, b
Voigt, C., Kleine, J., Sauer, D., Moore, R. H., Bräuer, T., Le Clercq, P., Kaufmann, S., Scheibe, M., Jurkat-Witschas, T., Aigner, M., Bauder, U., Boose, Y., Borrmann, S., Crosbie, E., Diskin, G. S., DiGangi, J., Hahn, V., Heckl, C., Huber, F., Nowak, J. B., Rapp, M., Rauch, B., Robinson, C., Schripp, T., Shook, M., Winstead, E., Ziemba, L., Schlager, H., and Anderson, B. E.: Cleaner burning aviation fuels can reduce contrail cloudiness, Commun. Earth Environ., 2, 114, https://doi.org/10.1038/s43247-021-00174-y, 2021. a
Wölk, J. and Strey, R.: Homogeneous Nucleation of H2O and D2O in Comparison: The Isotope Effect, J. Phys. Chem. B, 105, 11683–11701, https://doi.org/10.1021/jp0115805, 2001. a
Yu, F., Kärcher, B., and Anderson, B. E.: Revisiting Contrail Ice Formation: Impact of Primary Soot Particle Sizes and Contribution of Volatile Particles, Environ. Sci. Technol., 58, 17650–17660, https://doi.org/10.1021/acs.est.4c04340, 2024. a
Short summary
Contrail cirrus significantly contributes to aviation's overall climate impact. As hydrogen combustion and fuel cell use are emerging technologies for aircraft propulsion, we simulated individual contrails from hydrogen propulsion during the first 6 min after exhaust emission, termed the vortex phase. The ice crystal loss during that stage is crucial, as the number of ice crystals has a large impact on the further evolution of contrails into contrail cirrus and their radiative forcing.
Contrail cirrus significantly contributes to aviation's overall climate impact. As hydrogen...
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