Acoustic backscatter data were collected on board the RRS James Clark Ross (cruise JR200) as part of the Discovery 2010 programme. Data were collected using a Simrad EK60 echo sounder. This cruise ran two transects (Stanley to Signy and Signy to South Georgia) across the Scotia Sea in the austral autumn (March - April) of 2009. Within these transects, there were a series of stations at which dedicated acoustic transects were run, although the EK60 was run continuously throughout the cruise. JR200 was the third of three cruises which comprise the field studies of the Discovery 2010 programme. The programme was designed to analyse interactions in the Southern Ocean ecosystem. The raw data files (Simrad .raw format) are held by the Polar Data Centre (PDC) at the British Antarctic Survey (BAS). *******PLEASE BE ADVISED TO USE PROCESSED DATA******* The JR200 EK60 processed data is now available at https://doi.org/10.5285/7b86ed5f-0520-4dec-9d1e-f76be05b98c9.

Water column acoustic data collected in the Scotia Sea (from 2008-04-16 to 2008-04-17) during cruise JR186. Multi-frequency (38,120 and 200 kHz) acoustic data were collected using a Simrad EK60 echo sounder. The dataset comprises of calibrated and processed 38 kHz volume backscattering strength (Sv, dB re 1m-1). Data processing was undertaken using Echoview and Matlab. Processed netCDF data files are made available as part of the NERC Southern Ocean Network of Acoustics (SONA) and the EU MESOPP project.

Water column acoustic data collected in the Scotia Sea (from 2016-12-09 to 2017-01-15) during cruise JR16003. Multi-frequency (38,120 and 200 kHz) acoustic data were collected using a Simrad EK60 echo sounder. The dataset comprises of calibrated and processed 38 kHz volume backscattering strength (Sv, dB re 1m-1). Data processing was undertaken using Echoview and Matlab. Processed netCDF data files are made available as part of the NERC Southern Ocean Network of Acoustics (SONA) and the EU MESOPP project.

Acoustic backscatter data were collected on board the RRS James Clark Ross (cruise JR177) 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 summer from December 2007 - February 2008. Dedicated acoustic transects were also run at a number of stations within these transects. The EK60 was calibrated during JR177 (10-11th February 2008). More information about the calibration can be found in the Cruise Report for JR177: https://www.bodc.ac.uk/data/information_and_inventories/cruise_inventory/report/jr177.pdf JR177 was the second 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 JR177 EK60 processed data is now available at https://doi.org/10.5285/cfc33544-e1df-4202-9d4b-c99e7f8a51d4.

Water column acoustic data collected in the Scotia Sea (from 2015-11-13 to 2015-12-14) during cruise JR15002. Multi-frequency (38,120 and 200 kHz) acoustic data were collected using a Simrad EK60 echo sounder. The dataset comprises of calibrated and processed 38 kHz volume backscattering strength (Sv, dB re 1m-1). Data processing was undertaken using Echoview and Matlab. Processed netCDF data files are made available as part of the NERC Southern Ocean Network of Acoustics (SONA) and the EU MESOPP project.

Water column acoustic data collected in the Scotia Sea (from 2009-12-23 to 2009-12-30) during cruise JR228. Multi-frequency (38,120 and 200 kHz) acoustic data were collected using a Simrad EK60 echo sounder. The dataset comprises of calibrated and processed 38 kHz volume backscattering strength (Sv, dB re 1m-1). Data processing was undertaken using Echoview and Matlab. Processed netCDF data files are made available as part of the NERC Southern Ocean Network of Acoustics (SONA) and the EU MESOPP project.

Water column acoustic data collected in the Amundsen and Bellingshausen Seas (from 2008-02-26 to 2008-04-10) during cruise JR179. Multi-frequency (38,120 and 200 kHz) acoustic data were collected using a Simrad EK60 echo sounder. The dataset comprises of calibrated and processed 38 kHz volume backscattering strength (Sv, dB re 1m-1). Data processing was undertaken using Echoview and Matlab. Processed netCDF data files are made available as part of the NERC Southern Ocean Network of Acoustics (SONA) and the EU MESOPP project.

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.

Water column acoustic data collected in the Scotia Sea (from 2016-01-21 to 2016-02-21) during cruise JR15004. Multi-frequency (38,120 and 200 kHz) acoustic data were collected using a Simrad EK60 echo sounder. The dataset comprises of calibrated and processed 38 kHz volume backscattering strength (Sv, dB re 1m-1). Data processing was undertaken using Echoview and Matlab. Processed netCDF data files are made available as part of the NERC Southern Ocean Network of Acoustics (SONA) and the EU MESOPP project.

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.