Ocean Dynamics

, Volume 69, Issue 6, pp 679–699 | Cite as

Directional wave spectra at the regional scale with the KuROS airborne radar: comparisons with models

  • Eva Le MerleEmail author
  • Danièle Hauser
  • Céline Tison


In situ observations, satellite observations, and regional observations from airborne remote sensing are very useful to characterize sea state evolution and related physical processes, improve numerical modeling, and contribute to climate variable survey. Directional wave spectra describe the complexity of sea state and give access to parameters such as directional parameters (mean direction and directional distribution of energy) and frequency parameters (peak frequency, frequency spread). In this paper, directional ocean wave spectra and their parameters, retrieved from observations carried out with the airborne radar system KuROS during two field campaigns, are analyzed. These campaigns provide a very rich variety of meteorological conditions: high wind conditions either fetch-limited cases or mature sea conditions and moderate wind conditions and sea state dominated by swell. The objective of this paper is to compare the KuROS data set with numerical wave model outputs and buoy observations. This comparison aims first at assessing the performances on main wave parameters (significant wave height, mean direction at the peak, peak frequency) retrieved from KuROS in different conditions (wind sea, swell, mixed seas), and then, to discuss on parameters characterizing the shape of the wave spectra, namely the frequency and the directional spread. Results of the comparisons show that, due to the size of the KuROS radar footprint, ocean waves with dominant wavelengths lower than 200 m are the most appropriate situations for wave retrieval. They also show an overestimation of the model frequency spread and an underestimation of the model directional spread compare to KuROS and buoy data for both campaigns.


Ocean wave spectrum Numerical wave model Radar observations 



The authors thank the staff of the radar team at LATMOS for its involvement in the development and operation of KuROS. They also wish to thank the staff of the SAFIRE team who operated the ATR42 aircraft. The development and operation of the KuROS radar was funded by the French space agency Centre National d’Etudes Spatiales (CNES). The Lion buoy data were provided by Météo-France in the context of the HyMeX project. The Pierres Noires buoy data were provided by the CEREMA (Centre d’études et d’expertise sur les risques, l’environnement, la mobilité et l’aménagement).

We also thank Lotfi Aouf from Météo-France for providing us with the different runs of the MFWAM wave forecast, and Fabrice Ardhuin and Mickaël Accensi from the LOPS for providing us with the data of the WW3 run.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Université of Versailles Saint Quentin, Sorbonne Université, CNRS, LATMOSGuyancourtFrance
  2. 2.CNESToulouseFrance

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