The eruption of the Hunga Tonga–Hunga Ha'apai volcano in January 2022 triggered a global phenomenon, including an atmospheric wave and a volcano-meteorological tsunami (VMT). The tsunami, reaching as far as Callao, Peru, 10 000 km away, caused significant coastal impacts. This study delves into understanding these effects, particularly on vessel mooring safety. The findings underscore the importance of enhancing early warning systems and preparing port authorities for managing such rare events.

We show that ocean-bottom seismometers are controlled by bottom currents, but these are not always a function of the tidal forcing. Instead we suggest that the ocean bottom has a flow regime resulting from two possible contributions: the permanent low-frequency bottom current and the tidal current along the full tidal cycle, between neap and spring tides. In the short-period noise band the ocean current generates harmonic tremors that corrupt the dataset records.

Probabilistic seismic hazard assessment (PSHA) is the most common tool used to decide on the acceptable seismic risk by society and mitigation measures. In slowly deforming regions, such Iberia, the earthquake generation models (EGMs) for PSHA suffer from great uncertainty. In this work we propose two sanity tests to be applied to EGMs, comparing the EGM moment release with constrains derived from GNSS observations or neotectonic modelling. Similar tests should be part of other region studies.

We investigate the source of the 1761 earthquake and tsunami. The reanalysis of the tsunami travel times agrees with an earlier suggested source area. We check the geodynamic setting of the area and place a fault as an extension to an identified fault and use numerical modelling to distinguish between two candidate sources. One of our theories is compatible with the geodynamic setting and reproduces well the observed tsunami parameters.