200 kHz raw echosounder data collected on the Antarctic Circumnavigation Expedition during the austral summer of 2016/2017. ***** Dataset abstract ***** These data consist of raw echosounder observations in the Southern Ocean collected during the Antarctic Circumnavigation Expedition (ACE; legs 2, 3) and through the Atlantic Ocean (ACE leg 4) using an EK60 GPT operating at 200 kHz. The instrument was calibrated at South Georgia during the expedition (leg 3). ***** Original data collection **** Data were collected using an EK60 GPT operating a hull-mounted transducer on the R/V Akademik Tryoshnikov at a frequency of 200 kHz. Data were originally stored on hard drives in raw proprietary Simrad (Bergen, Norway) format (.raw) alongside their auxilliary files (.idx, .bot) produced using ER60 software running on a Windows computer. Data were not processed during collection. Data file formats are described in Kongsberg Maritime AS (2012). Data were saved into directories by the leg number of the expedition (2, 3 or 4) and date on which the files were saved (UTC). All filenames include the date and time (UTC) of when the file was saved (see dataset contents for format of this). Where the filename begins with PASSIVE, the transducer was running in passive mode to record background noise levels. ***** Data processing ***** These data have not undergone any processing. A pre-processed version of the data where the calibration parameters have been applied is available (Proud et al., 2020; doi: 10.5281/zenodo.3979480). ***** Quality checking ***** The instrument was calibrated at South Georgia during the expedition (Leg 3). The calibration parameters have not been applied to these raw data files. ***** Further information for interpreting the data and using the dataset ***** Aggregation to lower resolution: Data were stored at their original resolution and can be aggregated by depth/ping to produce lower resolution data. ***** Dataset contents ***** - *DYYYYMMDD-THHMMSS.idx, auxiliary files, binary - *DYYYYMMDD-THHMMSS.raw, data files, binary - *DYYYYMMDD-THHMMSS.bot, auxiliary files, binary - README.txt, metadata, text Data filenames include the date and time in the format DYYYYMMDD-THHMMSS where D denotes the date and T denotes the time. Date is in the format YYYYMMDD and time is given in the format HHMMSS which is the 24-hour clock. Both date and time are in UTC. Prefixes of filenames are ACE_- ACE_EK60_200kHz- PASSIVE_EK60_200kHz- PASSIVE_ ***** Dataset contact ***** Dr. Roland Proud, Pelagic Ecology Research Group, Scottish Oceans Institute, Gatty Marine Laboratory, University of St Andrews, UK. ORCID: 0000-0002-8647-5562. Email: rp43@st-andrews.ac.uk ***** Dataset license ***** This 200 kHz raw echosounder data collected on ACE is made available under the Creative Commons Attribution 4.0 International License (CC BY 4.0) whose full text can be found at https://creativecommons.org/licenses/by/4.0/ ***** Dataset citation ***** Please cite this dataset as: Proud, R., Le Guen, C., Fernandes, P., Everson, I., Bernasconi, M., Lawrence, J. and Brierley, A. (2020). 200 kHz raw echosounder data collected on the Antarctic Circumnavigation Expedition during the austral summer of 2016/2017. (Version 1.0) [Data set]. Zenodo. doi: 10.5281/zenodo.3979519