3.3 Meteorological and oceanographic long-term study
We detected that the mass mortality periods coincided with years when continuous southwest rough sea and winter storms, Xynthia (2010) and Emma (2018), hit the archipelagos (Figure 3). The average wave height during these anomalous winters was 2–3 m; the waves came from the south and southwest (Figure 2 and 3). This result was corroborated using wave height and direction average buoy data, from 2009–2019, and the satellite images captured daily by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite. For comparison purposes, four more normal winter periods were also included in our analysis. During these normal winters, the highest percentage of waves came from the northeast (Figure 3). SSTºC average was 20.7ºC during the winter of 2010 and 18.2ºC during the winter of 2018.