f7603147-f165-4d9c-9a1d-061bf0027eae Technical University of Denmark dtu@dtu.dk 2024-09-03T07:23:46.135Z EPSG:4326 Global marine heat waves: frequency, classification and distribution from 1996-2020 2023-11-08 https://www.vliz.be//en/imis?dasid=8235 This dataset comprises the global frequency, classification and distribution of marine heat waves (MHWs) from 1996-2020, in Chauhan et al. 2023 (https://doi.org/10.3389/fmars.2023.1177571). The classification was done based on their attributes and using different baselines. Daily SST values were extracted from the NOAA-OISST v2 high-resolution (0.25°) dataset from 1982-2020. MHWs were detected using the method presented by Hobday et al. 2016 (https://doi.org/10.1016/j.pocean.2015.12.014), and by using the 95th percentile of the accumulated temperature distribution to flag the extreme events. A shifting baseline of 8-year rolling period was selected between the years 1982-1996, since this period shows relatively stable maximum values of temperature across different ocean regions. The shifting baseline aims to account for the decadal changes of westerly winds, temperatures and ocean gyres circulations. The classification was done using the KMeans clustering algorithm to identify the relevant features of MHWs and classify them into separate groups based on feature similarities. This algorithm takes MHW features, namely duration, maximum intensity, rate onset and rate decline, as input vectors and applies clustering in the 4-dimensional feature space where each data point represents an MHW event. Note that all the MHWs features are standardized because unequal variances can put more weight on variables with smaller variances. This record comprehends the geospatial datasets of: Average number of MHW days per year (i.e., the sum of all MHW days divided by the total number of years, 1996-2020). Average cumulative intensity per year (i.e., the sum of cumulative intensity divided by the total number of years, 1996-2020). Total number of MHW events across the different periods averaged on the total number of years (1989-2020). The period 1982-1988 was only used as an initial baseline without calculating MHWs. Spatial distribution of three MHW categories: moderate MHWs, abrupt and Intense MHWs and extreme MHWs; displaying the total number of MHW days normalized by the number of years considered (i.e., 1989-2020). Distribution of Extreme MHWs across the different periods (A) 1989-1996, (B) 1997-2004, (C) 2005-2012, (D) 2013-2020. The relative frequency (γ) is a ratio of extreme MHWs in a specific period and all extreme MHWs in the same cluster for all periods. Technical University of Denmark (Denmark) Patrizio Mariani Technical University of Denmark dtu@dtu.dk Anshul Chauhan Technical University of Denmark dtu@dtu.dk https://sextant.ifremer.fr/geonetwork/srv/api/records/f7603147-f165-4d9c-9a1d-061bf0027eae/attachments/mhw2.png Oceanographic geographical features GEMET - INSPIRE themes, version 1.0 2018-07-27T14:39:48 geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme Global Spatial scope 2019-05-22 /Physical oceanography Mission Atlantic - BODC Parameters 2024-07-26 geonetwork.thesaurus.local.theme.mission-atlantic-bodc-parameters Atlantic Ocean Canary Current system Celtic Seas North Mid-Atlantic Ridge Norwegian Sea South Brazilian Shelf Southern Benguela South Mid-Atlantic Ridge Mission Atlantic - Case Studies 2024-07-26 geonetwork.thesaurus.local.theme.mission-atlantic-case-studies Environmental data Mission Atlantic - Data type (DMP) 2024-07-26 geonetwork.thesaurus.local.theme.mission-atlantic-data-type Article MISSION ATLANTIC Results Data Mission Atlantic - Resources 2024-07-26 geonetwork.thesaurus.local.theme.mission-atlantic-resources WP5 Assessing state, drivers and tipping points Mission Atlantic - Work Package 2024-07-26 geonetwork.thesaurus.local.theme.mission-atlantic-work-package /Physical Environment Thèmes Sextant 2024-07-26 geonetwork.thesaurus.local.theme.sextant-theme Attribution (CC BY) There are no limitations on public access to spatial data sets and services. 0.25 No linguistic content climatologyMeteorologyAtmosphere oceans -180.00 180.00 -70.00 70.00 1996-01-01 2020-12-31 NetCDF (Network Common Data Form) https://doi.org/10.3389/fmars.2023.1177571 WWW:LINK-1.0-http--link Scientific publication https://www.vliz.be/en/imis?module=dataset&dasid=8235 WWW:LINK IMIS catalogue Technical Guidance for the implementation of INSPIRE dataset and service metadata based on ISO/TS 19139:2007 2017-03-02 This metadata set is conformant with the Technical Guidance for the implementation of INSPIRE dataset and service metadata based on ISO/TS 19139:2007 true 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 Conformance of this data set with the INSPIRE Implementing Rules for the interoperability of spatial data sets and services was not evaluated Daily SST was extracted from NOAA-OISST v2 high resolution (0.25°) dataset from 1982-2020. MHWs are detected using the method presented in Hobday et al. (2016), using the 95th percentile of the accumulated temperature distribution to flag the extreme events. The period from 1982-1996 was used as a baseline. The KMeans clustering algorithm was used for MHW classification. See abstract for further details.