[ARCHIVE] Iberia Biscay Ireland Sea Level extreme from Observations Reprocessing

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'''DEFINITION''' The CMEMS IBI_OMI_SL_extreme_var_slev_mean_and_anomaly_obs OMI indicator is based on the computation of the 99th and the 1st percentiles from in situ data (observations). It is computed for the variable sea level measured by tide gauges along the coast. The use of percentiles instead of annual maximum and minimum values, makes this extremes study less affected by individual data measurement errors. The annual percentiles referred to annual mean sea level are temporally averaged and their spatial evolution is displayed in the dataset ibi_omi_sl_extreme_var_slev_mean_and_anomaly_obs, jointly with the anomaly in the target year. This study of extreme variability was first applied to sea level variable (Pérez Gómez et al 2016) and then extended to other essential variables, sea surface temperature and significant wave height (Pérez Gómez et al 2018).

'''CONTEXT''' Sea level (SLEV) is one of the Essential Ocean Variables most affected by climate change. Global mean sea level rise has accelerated since the 1990’s (Abram et al., 2019, Legeais et al., 2020), due to the increase of ocean temperature and mass volume caused by land ice melting (WCRP, 2018). Basin scale oceanographic and meteorological features lead to regional variations of this trend that combined with changes in the frequency and intensity of storms could also rise extreme sea levels up to one metre by the end of the century (Vousdoukas et al., 2020). This will significantly increase coastal vulnerability to storms, with important consequences on the extent of flooding events, coastal erosion and damage to infrastructures caused by waves.

'''CMEMS KEY FINDINGS''' The mean 99th percentiles reflect the tidal amplitude spatial variability, from 1.1 m above mean sea level in the southernmost area, the Canary Islands, to 5.6 m in Saint Malo, in the English Channel. The standard variation reflects the south-north increase of storminess, ranging between 1-2 cm in the Canary Islands to 9 cm in Saint Malo. Small positive anomalies of around 2 cm are observed in the northernmost stations of the Canary Islands for 2019. Positive values with larger spatial variability are also found near the English Channel, reaching 6 cm in Saint Malo. Along the Iberian coast, the anomalies are smaller, null and even negative at some stations like Bonanza (Gulf of Cadiz, Guadalquivir river mouth), where it reaches -3 cm.

""Note: The key findings will be updated annually in November, in line with OMI evolutions.

'''DOI (product):''' https://doi.org/10.48670/moi-00253