b477ec44-fecb-43fa-9679-4d10291340c1 Copernicus Marine Service product specification CMEMS servicedesk.cmems@mercator-ocean.eu http://marine.copernicus.eu/ 2025-10-22T07:20:23.453553Z ISO 19139, MyOcean profile 0.2 2 false WGS 84 (EPSG:4326) EPSG Iberia Biscay Ireland significant wave height extreme variability mean and anomaly (observations) OMI_EXTREME_WAVE_IBI_swh_mean_and_anomaly_obs 2023-11-30 3.4 2025-11-25 ef932fc0-04e7-4a25-b7b2-08a2d85d4039 '''DEFINITION''' The OMI_EXTREME_WAVE_IBI_swh_mean_and_anomaly_obs indicator is based on the computation of the 99th and the 1st percentiles from in situ data (observations). It is computed for the variable significant wave height (swh) measured by in situ buoys. The use of percentiles instead of annual maximum and minimum values, makes this extremes study less affected by individual data measurement errors. The percentiles are temporally averaged, and the spatial evolution is displayed, 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''' Projections on Climate Change foresee a future with a greater frequency of extreme sea states (Stott, 2016; Mitchell, 2006). The damages caused by severe wave storms can be considerable not only in infrastructure and buildings but also in the natural habitat, crops and ecosystems affected by erosion and flooding aggravated by the extreme wave heights. In addition, wave storms strongly hamper the maritime activities, especially in harbours. These extreme phenomena drive complex hydrodynamic processes, whose understanding is paramount for proper infrastructure management, design and maintenance (Goda, 2010). In recent years, there have been several studies searching possible trends in wave conditions focusing on both mean and extreme values of significant wave height using a multi-source approach with model reanalysis information with high variability in the time coverage, satellite altimeter records covering the last 30 years and in situ buoy measured data since the 1980s decade but with sparse information and gaps in the time series (e.g. Dodet et al., 2020; Timmermans et al., 2020; Young & Ribal, 2019). These studies highlight a remarkable interannual, seasonal and spatial variability of wave conditions and suggest that the possible observed trends are not clearly associated with anthropogenic forcing (Hochet et al. 2021, 2023). In the North Atlantic, the mean wave height shows some weak trends not very statistically significant. Young & Ribal (2019) found a mostly positive weak trend in the European Coasts while Timmermans et al. (2020) showed a weak negative trend in high latitudes, including the North Sea and even more intense in the Norwegian Sea. For extreme values, some authors have found a clearer positive trend in high percentiles (90th-99th) (Young, 2011; Young & Ribal, 2019). '''COPERNICUS MARINE SERVICE KEY FINDINGS''' The mean 99th percentiles showed in the area present a wide range from 2-3.5m in the Canary Island with 0.1-0.3 m of standard deviation (std), 3.5m in the Gulf of Cadiz with 0.5m of std, 3-6m in the English Channel and the Irish Sea with 0.5-0.6m of std, 4-7m in the Bay of Biscay with 0.4-0.9m of std to 8-10m in the West of the British Isles with 0.7-1.4m of std. Results for this year show slight negative anomalies in the Canary Island (-0.4/0.0m) and in the Gulf of Cadiz (-0.8m) barely out of the standard deviation range in both areas, slight positive or negative anomalies in the West of the British Isles (-0.6/+0.4m) and in the English Channel and the Irish Sea (-0.6/+0.3m) but inside the range of the standard deviation and a general positive anomaly in the Bay of Biscay reaching +1.0m but close to the limit of the standard deviation. '''DOI (product):''' https://doi.org/10.48670/moi-00250 E.U. Copernicus Marine Service Information INS-PUERTOS-MADRID-ES;INS-NOWSYSTEMS-MADRID-ES P0M0D0H/P0M0D0H N/A https://documentation.marine.copernicus.eu/IMG/OMI_EXTREME_WAVE_IBI_swh_mean_and_anomaly_obs.png Oceanographic geographical features GEMET - INSPIRE themes, version 1.0 2009-09-22 in-situ-observation Discipline 2024-07-26 geonetwork.thesaurus.local.discipline.myocean.discipline swh_percentile99_mean swh_percentile1_mean swh_percentile99_anomaly swh_percentile1_anomaly swh_percentile99_targetyear swh_percentile99_std swh_percentile1_targetyear swh_percentile1_std Climate and Forecast Standard Names 2017-04-04 geonetwork.thesaurus.external.parameter.myocean.ocean-variables multi-year Temporal scale 2024-07-26 geonetwork.thesaurus.local.temporal-scale.myocean.temporal-scale weather-climate-and-seasonal-forecasting marine-safety marine-resources coastal-marine-environment Area of benefit 2025-07-29 geonetwork.thesaurus.local.area-of-benefit.myocean.area-of-benefit iberian-biscay-irish-seas Reference Geographical Areas 2024-07-26 geonetwork.thesaurus.local.reference-geographical-area.myocean.reference-geographical-area N/A Processing level 2024-07-26 geonetwork.thesaurus.local.processing-level.myocean.processing-level Not Applicable Model assimilation 2016-02-03 geonetwork.thesaurus.external.theme.myocean.model-assimilation See Copernicus Marine Environment Monitoring Service Data commitments and licence at: http://marine.copernicus.eu/web/27-service-commitments-and-licence.php No limitations on public access Dodet G, Piolle J-F, Quilfen Y, Abdalla S, Accensi M, Ardhuin F, et al. 2020. The sea state CCI dataset v1: Towards a sea state climate data record based on satellite observations. https://dx.doi.org/10.5194/essd-2019-253 2019-05-08 Mitchell JF, Lowe J, Wood RA, & Vellinga M. 2006. Extreme events due to human-induced climate change. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 364(1845), 2117-2133. 2019-05-08 Pérez-Gómez B, Álvarez-Fanjul E, She J, Pérez-González I, Manzano F. 2016. Extreme sea level events, Section 4.4, p:300. In: Von Schuckmann K, Le Traon PY, Alvarez-Fanjul E, Axell L, Balmaseda M, Breivik LA, Brewin RJW, Bricaud C, Drevillon M, Drillet Y, Dubois C , Embury O, Etienne H, García-Sotillo M, Garric G, Gasparin F, Gutknecht E, Guinehut S, Hernandez F, Juza M, Karlson B, Korres G, Legeais JF, Levier B, Lien VS, Morrow R, Notarstefano G, Parent L, Pascual A, Pérez-Gómez B, Perruche C, Pinardi N, Pisano A, Poulain PM , Pujol IM, Raj RP, Raudsepp U, Roquet H, Samuelsen A, Sathyendranath S, She J, Simoncelli S, Solidoro C, Tinker J, Tintoré J, Viktorsson L, Ablain M, Almroth-Rosell E, Bonaduce A, Clementi E, Cossarini G, Dagneaux Q, Desportes C, Dye S, Fratianni C, Good S, Greiner E, Gourrion J, Hamon M, Holt J, Hyder P, Kennedy J, Manzano-Muñoz F, Melet A, Meyssignac B, Mulet S, Nardelli BB, O’Dea E, Olason E, Paulmier A, Pérez-González I, Reid R, Racault MF, Raitsos DE, Ramos A, Sykes P, Szekely T, Verbrugge N. 2016. The Copernicus Marine Environment Monitoring Service Ocean State Report, Journal of Operational Oceanography. 9 (sup2): 235-320. http://dx.doi.org/10.1080/1755876X.2016.1273446 2019-05-08 Pérez Gómez B, De Alfonso M, Zacharioudaki A, Pérez González I, Álvarez Fanjul E, Müller M, Marcos M, Manzano F, Korres G, Ravdas M, Tamm S. 2018. Sea level, SST and waves: extremes variability. In: Copernicus Marine Service Ocean State Report, Issue 2, Journal of Operational Oceanography, 11:sup1, Chap. 3.1, s79–s88, DOI: https://doi.org/10.1080/1755876X.2018.1489208. 2019-05-08 Stott P. 2016. How climate change affects extreme weather events. Science, 352(6293), 1517-1518. 2019-05-08 cec2bc48-06bc-41cb-913b-599c866a54fe a6160dd4-3477-4b07-aac3-752f3868dd5b 2512e19a-6eb8-47c2-ba70-16347258bcae Young IR, Zieger S, and Babanin AV. 2011. Global Trends in Wind Speed and Wave Height, Science, 332, 451–455, https://doi.org/10.1126/science.1197219 2019-05-08 Young IR & Ribal A. 2019. Multiplatform evaluation of global trends in wind speed and wave height. Science, 364, 548–552. https://doi.org/10.1126/science.aav9527 2019-05-08 Timmermans BW, Gommenginger CP, Dodet G, Bidlot JR. 2020. Global wave height trends and variability from new multimission satellite altimeter products, reanalyses, and wave buoys, Geophys. Res. Lett., № 47. https://doi.org/10.1029/2019GL086880 2019-05-08 Hochet A, Dodet G, Ardhuin F, Hemer M, Young I. 2021. Sea State Decadal Variability in the North Atlantic: A Review. Climate 2021, 9, 173. https://doi.org/10.3390/cli9120173 Goda Y. 2010. Random seas and design of maritime structures. World scientific. https://doi.org/10.1142/7425. 2019-05-08 Hochet A, Dodet G, Ardhuin F, Hemer M, Young I. 2021. Sea State Decadal Variability in the North Atlantic: A Review. Climate 2021, 9, 173. https://doi.org/10.3390/cli9120173 Goda Y. 2010. Random seas and design of maritime structures. World scientific. https://doi.org/10.1142/7425. 2019-05-08 eng oceans bounding box -23.00 14.00 26.00 56.00 0 2000-01-01 2023-12-31 0 0.0 display priority: 99999 observation vertical level number: 1 false Grid NetCDF-4 https://stac.marine.copernicus.eu/metadata/OMI_EXTREME_WAVE_IBI_swh_mean_and_anomaly_obs/omi_extreme_wave_ibi_swh_mean_and_anomaly_obs_202311/dataset.stac.json WWW:STAC omi_extreme_wave_ibi_swh_mean_and_anomaly_obs For accessing native data and Analysis-ready Cloud-optimized data services, consult this STAC metadata endpoint https://wmts.marine.copernicus.eu/teroWmts/OMI_EXTREME_WAVE_IBI_swh_mean_and_anomaly_obs/omi_extreme_wave_ibi_swh_mean_and_anomaly_obs_202311?service=WTMS&request=GetCapabilities OGC:WMTS omi_extreme_wave_ibi_swh_mean_and_anomaly_obs COMMISSION REGULATION (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 See the referenced specification The myOcean products depends on other products for production or validation. The detailed list of dependencies is given in ISO19115's aggregationInfo (ISO19139 Xpath = "gmd:MD_Metadata/gmd:identificationInfo/gmd:aggregationInfo[./gmd:MD_AggregateInformation/gmd:initiativeType/gmd:DS_InitiativeTypeCode/@codeListValue='upstream-validation' or 'upstream-production']")