The datasets refer to the dating of three basaltic samples collected from Bruce Bank and Jane Bank in the southern Scotia Sea. The samples were dredged from depths between 850 -1900 m from steep scrap slopes at two locations (DR.225: 59.927 degrees S, 39.154 degrees W; DR.84: 62.468 degrees S, 039.785 degrees W). The files include full analytical datasets for 40Ar/39Ar analysis of whole rock and plagioclase mineral separates performed at the Open University, UK in June 2022. This project was funded by NERC NC-ALI funding to Geology & Geophysics.

We present a new bathymetric compilation of the greater South Georgia region, here defined by a bounding box of ~900km (45W to 19W) by ~580km (63S to 50S) and covering an area of 530,000 km2. The region includes the South Georgia shelf, the Shag Rock shelf (to the west of South Georgia), the surrounding continental slopes and adjacent deep sea. This bathymetry grid was compiled from a variety of different data sources including multibeam swath bathymetry collected from scientific cruises undertaken by British Antarctic Survey (BAS), Alfred Wegener Institute (AWI) and the Institute of Geophysics, University of Texas. The grid has been constructed using a layered hierarchy dependent on accuracy of each dataset. The data is available as a 100m resolution GeoTIFF, ESRI ascii grid or KMZ file of elevation data along with a shapefile indicating the spatial coverage of all the contributing datasets. This work was supported by the National Environmental Research Council (grant number NE/L002531/1). For further information regarding the creation of this dataset please refer to doi:10.1038/srep33163.

Acoustic backscatter data were collected on board the RRS James Clark Ross (cruise JR161) as part of the Discovery 2010 programme. Data were collected using a Simrad EK60 echo sounder at 38, 120 and 200 kHz. The EK60 was run continuously from Stanley (Falkland Islands) to Signy (South Orkney Islands), then to South Georgia across the Scotia Sea in the austral spring (October - December) of 2006. Dedicated acoustic transects were also run at eight stations within these transects. The EK60 was calibrated prior to data collection on a previous cruise (JR159 on 13-14th October 2006). More information about the calibration can be found in the Cruise Report for JR159: https://www.bodc.ac.uk/data/information_and_inventories/cruise_inventory/report/jr152_jr159.pdf JR161 was the first of three cruises which comprise the field studies of the British Antarctic Survey''s (BAS) core science Discovery 2010 programme, funded by the Natural Environment Research Council. *******PLEASE BE ADVISED TO USE PROCESSED DATA******* The JR161 EK60 processed data is now available at https://doi.org/10.5285/c831d5e4-8d03-4aea-a6c6-6db101f36d8d.

We present two new gridded bathymetric compilations of the Orkney Passage, Scotia Sea here defined by the following bounding boxes: 39.1 to 39.6 W, 60.55 to 60.7 S and 41.7 to 42.6 W, 60.45 to 60.8 S. These bathymetry grids were compiled from a variety of multibeam swath bathymetry data acquired during 12 different cruises (see lineage). The data is available as grids of 50 m resolution in a GMT-compatible (2-D) NetCDF format using geographic coordinates on the WGS84 datum. This grid was compiled in support of the ongoing monitoring efforts in and around Orkney Passage as part of the Ocean Regulation of Climate by Heat and Carbon Sequestration and Transports (ORCHESTRA) programme and preceding BAS NC projects, and the Dynamics of the Orkney Passage Outflow (DynOPO) project. Funding was provided by the NERC grants NE/K012843/1 and NE/N018095/1 as well as national capability

Mesopelagic fish were sampled in the Scotia Sea using a 25 m2 opening and closing rectangular midwater trawl during five research cruises on RRS John Biscoe and RRS James Clark Ross. Nets sampled discrete layers, from the surface to 1000 m during austral spring, summer and autumn. The data include 17726 individual fish records from 66 taxa, the most abundant of which were myctophids of the genera Electrona, Gymnoscopelus, Krefftichthys and Protomyctophum and bathylagids (Bathylagus sp.). Length (standard length, total length or pre-anal fin length) was measured for the majority of specimens (16837), with sex and weight data also collected for many. The work was conducted as part of the BAS Ecosystems Programmes funded by the UK Natural Environment Research Council.

This is data set held in two csv files, one DATA file contains the data and an accompanying NOTES file that provides additional detail on abbreviations. It contains processed acoustic backscatter (NASC) data that is coupled with environmental data. Acoustic backscatter data is from 13 acoustic transects spanning the Scotia Sea and major Southern Ocean fronts, obtained during cruises JR161, JR177, JR200, JR15002, JR15004 and JR16003 (2006-2017). Data were collected using a Simrad EK60 echo sounder at 38 kHz. The EK60 was run continuously between Stanley (Falkland Islands) and Signy (South Orkney Islands), Stanley and South Georgia. Environmental data includes: sea surface temperature, bathymetry, geopotential height, geostrophic current speeds, sea ice concentration, sea ice zone, time of day (day/night), sea temperature at 200m, distance to coast, net primary productivity, and hours of daylight. Environmental data are compiled from external data sources. Funding was provided by the NERC grants NE/L002434/1 and bas010017.

This dataset contains the mean position of the Southern Antarctic Circumpolar Current front (SACCF) in the Scotia Sea, southwest Atlantic sector of the Southern Ocean. The location of the front was determined from analysis of the geopotential anomaly field calculated from quality-controlled potential temperature and salinity data from the World Ocean Database 1998 (Levitus et al., 1998) supplemented by an additional hydrographic profile obtained from the Scripps Institute of Oceanography, as detailed by Thorpe (2001) and Thorpe et al. (2002). The geopotential anomaly data were gridded at a horizontal resolution of one quarter degree and spanned the period 1911-1990. The front position was generated as part of a studentship awarded to SE Thorpe, funded by the Natural Environment Research Council with CASE support from the British Antarctic Survey. The studentship was supervised by KJ Heywood, MA Brandon and DP Stevens.

Among all possible interaction types, trophic interactions are easily observable and essential in terms of energy transfer, and thus binary networks have arisen as the most straightforward method to describe complex ecological communities. These food-web models also inform on the ecosystem dynamics and function, and the patterns arising from food web topology can be indicators for ecosystem stability. We present a comprehensive pelagic network for the Scotia Sea underpinned by surveys and dietary studies conducted in the Scotia Sea in the last century. Selection of the trophic links followed a protocol based on taxonomy and geographic location, and was further refined based on the consumer and resource depth ranges and their body size ratios. The resulting network consists on 228 nodes and 10880 links which represent the main trophic paths in the Scotia Sea ecosystem and can serve as a basis for ecosystem modelling in the Scotia Sea or comparison with other ecosystems. Funding was provided by NERC Highlight Topic grant NE/N005937/1 and NERC Fellowship NE/L011840/1.

This dataset comprises conventional stomachs contents data for the biomass-dominant species of mesopelagic fish, particularly myctophid fish (Family Myctophidae) in the Scotia Sea. The data were collected by depth-discrete RMT25 net trawls deployed between 0-1000 m between the Antarctic Polar Front and the South Orkney Islands. Samples were collected repeatedly at nominal sampling stations during austral autumn 2004, spring 2006, summer 2008 and autumn 2009 for analyses examining the trophodynamics of Southern Ocean mesopelagic fish and their role in the food web. The data are the quantitative measures of diet composition (prey abundance, frequency and mass) observed from microscope analyses of individual fish stomachs per species.

This dataset contains processed acoustic backscatter data that reflect integrated density estimates for Antarctic krill (Euphausia superba). The acoustic backscatter data are from the Western Core Box (WCB), comprising 8 acoustic transects that span the shelf-break at South Georgia. The data were obtained from a time series of 22 cruises carried out between 1996/97 and 2019/20. Data were collected using either a Simrad EK500 or EK60 echo sounder by biological oceanographers working at the British Antarctic Survey under the Ecosystems scientific research programme and predecessor Discovery 2010 and Dynamo research programmes. Funding was provided by the NERC/BAS Antarctic, Logistic, Infrastructure (ALI) Science and predecessor Long Term Monitoring Science research programmes.