Articles | Volume 19, issue 4
https://doi.org/10.5194/gmd-19-1769-2026
© 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-19-1769-2026
© 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
| 
03 Mar 2026
Development and technical paper |
| 03 Mar 2026
| 03 Mar 2026
Implementation of a sigma coordinate system in PALM-Sigma v1.0 (based on PALM v21.10) for LES study of the marine atmospheric boundary layer
Geophysical Institute, University of Bergen and Bergen Offshore Wind Centre, Allégaten 55, 5007 Bergen, Norway
Mostafa Bakhoday-Paskyabi
Geophysical Institute, University of Bergen and Bergen Offshore Wind Centre, Allégaten 55, 5007 Bergen, Norway
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Waves interact with the overlying wind field by modifying the stresses at the atmosphere–ocean interface. We develop and employ a parameterization method of wave-induced stresses in the numerical simulation of an offshore wind farm in a stable atmospheric boundary layer. This work demonstrates how swells change the kinetic energy transport and induce wind veer and wake deflection, leading to significant variations in the power output of wind turbines at different positions of the wind farm.
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The exchange of momentum and energy between the atmosphere and ocean depends on air–sea processes, especially wave-related ones. Precision in representing these interactions is vital for offshore wind turbine and farm design and operation. The development of a reliable wave–turbulence decomposition method to remove wave-induced interference from single-height wind measurements is essential for these applications and enhances our grasp of wind coherence within the wave boundary layer.
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We described a new automated method to separate the wind turbine wake from the undisturbed flow. The method relies on the wind speed distribution in the measured wind field to select one specific threshold value and split the measurements into wake and background points. The purpose of the method is to reduce the amount of data required – the proposed algorithm does not need precise information on the wind speed or direction and can run on the image instead of the measured data.
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Short summary
Ocean waves shape winds close to the surface and extend their impact throughout the atmospheric boundary layer. In this study, we built a new modeling tool that allows simulations to follow the moving wave surface itself. By testing different wave and wind conditions, we show how waves change air motion, turbulence, and energy exchange above the ocean. This approach improves our ability to represent air–sea interactions, with implications for weather studies and offshore wind energy.
Ocean waves shape winds close to the surface and extend their impact throughout the atmospheric...
