Extreme sea levels at Rapa Nui (Easter Island) during intense atmospheric rivers

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TítuloExtreme sea levels at Rapa Nui (Easter Island) during intense atmospheric rivers
Año2021
AutorFelipe Igualt, Matías Carvajal, Patricio Winckler, René Garreaud, Manuel Contreras-López, Pamela Averil, Marco Cisternas, Alejandra Gubler, Wolfgang Breuer
Tipo de PublicaciónArtículo en Revista Académica
RevistaNatural Hazards
Edición106(2)
Páginas1619-1637
Palabras ClaveRapa Nui, Easter Island, seiches, meteotsunamis, storm surge, sea level, shelf resonance, atmospheric rivers, integrated water vapor
Área de InvestigaciónExtensión, Ciudad y Habitabilidad
LíneaCiudad y Extensión
Código
https://doi.org/10.1007/s11069-020-04462-2
URLhttps://link.springer.com/article/10.1007/s11069-020-04462-2
Carreras RelacionadasArquitectura, Náutico y Marítimo"Náutico y Marítimo" is not in the list (Arquitectura, Diseño, Magíster, Otra) of allowed values for the "Carreras Relacionadas" property., Ciudad y Territorio"Ciudad y Territorio" is not in the list (Arquitectura, Diseño, Magíster, Otra) of allowed values for the "Carreras Relacionadas" property.

Resumen

In addition to the tsunami hazard posed by distant great earthquakes, Rapa Nui (Easter Island), in the Southeast Pacific Ocean, is exposed to frequent and intense coastal storms. Here, we use sea-level records and field surveys guided by video and photographic footage to show that extreme sea levels at Rapa Nui occur much more frequent than previously thought and thus constitute an unrecognized hazard to the inland’s maritime supply chain. We found that extreme sea-level events, including the two most extreme (March 5th and May 5th, 2020) in our 17-month-long analyzed period (from January 1st, 2019, to May 31st, 2020), resulted from constructive superpositions of seiches on the shelf, storm surges and high tides. By further analyzing time series of atmospheric and wind-generated wave data, we conclude that these extreme sea levels are ultimately driven by the breaking of large waves near the coastline (i.e., wave setup), with lesser contribution of barometric setup and even less of wind setup. We also propose that these large waves were mainly generated from strong, long-lasting, NW winds associated with intense atmospheric rivers (long, narrow regions in the atmosphere that transport abundant water vapor) passing over Rapa Nui. Given that the intensity of atmospheric rivers and sea level are thought to increase as climate changes, a deeper understanding of the relation between meteorological and oceanographic processes at Rapa Nui is strongly needed.