Linear and non-linear sea-level variations in the Adriatic Sea from tide gauge records (1872-2012)

• Published in: Annals of Geophysics
• Main Authors: Gaia Galassi, Giorgio Spada
• Format: Article in Journal/Newspaper
• Language: English
• Published: Istituto Nazionale di Geofisica e Vulcanologia (INGV) 2015
• Subjects: Sea–level rise; Tide gauge observations; EEMD; Adriatic Sea; Atlantic modes; Meteorology. Climatology; QC851-999; Geophysics. Cosmic physics; QC801-809; North Atlantic; North Atlantic oscillation
• Online Access: https://doi.org/10.4401/ag-6536; https://doaj.org/article/a6abf575104a42319f6b4c407ddb451b

We have analyzed tide gauge data from the Adriatic Sea in order to assess the secular sea-level trend, its acceleration and the existence of possible cyclic variation. Analyzing the sea-level stack of all Adriatic tide gauges, we have obtained a trend of (1.25±0.04) mm yr -1 , in agreement with that observed for the last century in the Mediterranean Sea, and an acceleration that is negligibile compared to the average global values. By means of the Ensemble Empirical Mode Decomposition technique, we have evidenced an energetic oscillation with a period of ∼ 20 years that we relate with the recurrence of opposite phases in the Atlantic Multi–decadal Oscillation and North Atlantic Oscillation indices. We suggest that anomalously high sea-level values observed at all the Adriatic tide gauges during 2010 and 2011 can be explained by the rising phase of this 20 years cycle.