Evolution of the tidal semi-diurnal constituent M2 at Brest from 1846 to 2005

Évolution de l'onde semi-diurne M2 de la marée à Brest de 1846 à 2005

Nicolas Pouvreau (1) , Belen Martin-Miguez (2) , Bernard Simon (2) , Guy Woppelmann (1)

1 CLDG - Centre littoral de géophysique
2 SHOM - Service Hydrographique et Océanographique de la Marine

The work of searching, recovering and quality control of ancient sea-level measurements at Brest is presented. This work enables us to complete a study carried out by Cartwright in 1972, which showed a decrease in the tidal M2 semi-diurnal amplitude of 1% per century. After including these ancient data, as well as the last four decades of observations in the analysis, our results show an increase of the amplitude of M2 after 1960 and a decrease before 1880, suggesting a long-period oscillation rather than a steady secular trend.

Mots clés: Tides; Tide gauges; Sea-level variations; Brest; France

Domaines: Océan, Atmosphère

Nicolas Pouvreau, Belen Martin-Miguez, Bernard Simon, Guy Woppelmann. Évolution de l'onde semi-diurne M2 de la marée à Brest de 1846 à 2005. Comptes Rendus Géoscience, 2006, 338 (11), pp.802-808. ⟨10.1016/j.crte.2006.07.003⟩. ⟨hal-01248259⟩