Summary: | Maintenance and Update Frequency: notPlanned Statement: The vertical temperature-salinity profiles used in this sdata set were collected by southern elephant seals (Mirounga leonina) instrumented with Conductivity-Temperature-Depth Satellite-Relayed Data Loggers (CTD-SRDLs) during their annual post-molt (February–November) foraging trips. The profile data were retrieved from the Marine Mammals Exploring the Oceans Pole to Pole (MEOP) data- base (http://www.meop.net/). The processing involved in this data set comprises the monthly delimitation of East Antartic polynyas between 2004 and 2019 and the assignation of the data profiles to any of the 18 detected polynyas. We identified polynyas using a combination of dynamic sea-ice concentration and static bathymetric data. First, the whole region was divided into coarse-scale polygons, each one containing one polynya as based on previous descriptions in the literature (Amblas & Dowdeswell, 2018; Arrigo & van Dijken, 2003; Labrousse et al., 2018; Tamura et al., 2016). After this first identification, two criteria were used to define the area of each polynya and to assign seal CTD profiles to them. In winter (from April to October), monthly sea-ice concentration contours of 75% within each polygon were selected and all data inside those contours were assigned to belong to the given polynya. With this method, polynya surface area changes monthly. In summer (from November to March), when most of the region is indeed ice-free, we assigned CTD profiles that were located within the 75% contours of mean sea- ice concentration between April and October of the preceding winter. To avoid including data off the continental shelf, the contours are further constrained by the continental slope (defined by depths<1,500 m). Credit The seal CTD-SRDL tags and deployment were funded and supported through a collaboration between the French Polar Institute (program 109: PI. H. Weimerskirch and 1201: PI. C. Gilbert and C. Guinet), the SNO-MEMO and CNES-TOSCA and the ...
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