Directional wave measurements from three wave sensors during the FETCH experiment

International audienceDuring the Flux, Etat de la mer et Télédéction en Condition de fetcH variable (FETCH) experiment, directional wave measurements were made by an airborne radar RESSAC and by two moored buoys, an Air-Sea Interaction Spar (ASIS) and a Directional Waverider. In order to define the performance and compatibility of these wave sensors with different measuring principles, a comparison of the directional measurements in a variety of meteorological conditions during the experiment is presented in this paper. It was found that within the limits of their operational ranges, the sensors agreed on the one-dimensional spectrum and the basic parameters derived from it--significant wave height and peak frequency. The sensors reported the directional features of the wave field and the mean direction consistently, but in some cases the two buoys disagreed on the directional width of the spectrum. Most of these cases were associated with a single swell-dominated event