A total of 19 stations were sampled between August and October 2011 onboard the Canadian research icebreaker CCGS Amundsen. Two stations were sampled both in August and October to assess seasonal variability in stable isotope composition. At each station, a USNEL box corer (0.25 m2) was deployed to collect seafloor sediments for the determination of stable isotope composition and pigment (Chl a + phaeopigments) concentrations. From each box core, surface sediments (upper 1 cm) were sampled as three sub-cores using a 60 ml disposable syringe (2.6 cm diameter with a cut off anterior end). Sediment samples were immediately frozen at -20 °C for stable isotope analysis and at -80 °C for pigment analysis. Megabenthic invertebrates were principally collected with an Agassiz trawl (effective opening of 1.5 m and a net mesh size of 40 mm, with a 5 mm cod end liner) with average trawling time and speed of 5 min and 1.5 knots, respectively. At three stations, invertebrates were collected with the box corer. Trawl and box corer catches were washed over a 2 mm sieve under running sea water onboard and 1 to 3 individuals of the most abundant community representatives were collected at each station. Specimens were frozen immediately at -80 °C and identified to the lowest possible taxonomic level in the lab.

Geophysical data from a single-channel 3.5kHz sub-bottom profiler is acquired 24hrs during CCGS Amundsen’s cruises by a Knudsen 320-BR (2014 and 2015 cruises) and a 3260 (2016 cruise) sub-bottom profiler. The sounder is comped of 16 (4x4 array) transducers outputting a total of 10KW. The dataset consists of raw (keb and sgy) and processed (JPEG2000 and PNG images) data. Heave (TSS1 form the Applanix POS-MV) and GPS (ZDA, VTG, GGA from the CNAV GNSS Receiver) data are inputted to the raw data files directly during acquisition. The processing is made using the NRCAN software suite (SEGY to SGYJP2 and SegyJp2Viewer). The speed of sound is constantly set to 1500 m/s. The data are available per year (2014 to 2016) in an ESRI ArcGIS geodatabase format where shiptrack lines are linked to png images of the sub-bottom profile.

Accoustic data was generated using an EM300 (2003-2008) and EM302 (2008-2017) multibeam sonar system onboard the CCGS Amundsen during ArcticNet Cruises. This bathymetric dataset covers the Canadian Arctic and includes all bathymetric data collected from CCGS Amundsen. The dataset consists of high-resolution bathymetry and acoustic backscatter imagery collected 24 hours a day, whenever the ship was in transit or during dedicated survey time. Standard collection settings used dual-ping, FM pulse, auto depth mode, angular coverage of +/- 60 degrees and high density equidistant beam forming. The SIS software was used to collect the data. From 2003-2013, near realtime cleaning of data outliers was done using the Ocean Mapping Group's Swathed toolkit after conversion to OMG binary format. After 2014, the data cleaning was done using CARIS HIPS&SIPS software. Data was exported in Generic Sensor Format (.gsf). IMU data was parsed by SIS from a POSMv 320 v.4. RTG GPS data from the CNAV 3050 GNSS receiver was used to correct and improve the position output from the POSMV via a RTCM correction protocol. Soundspeed information was either from CTD Rosette casts, MVP300 data or simulated from the World Ocean Atlas 2009 database. Data are gridded at a resolution of 10 metres. Grid files available are in binary floating point file (.flt). The grids will be available shortly on the Université Laval library's geospatial center website (www.geoindex-plus.bibl.ulaval.ca/). Note: 2003-2013 data was collected and processed by the OMG of University of New Brunswick (www.omg.unb.ca/Projects). 2014-2017 data was collected and processed by the Marine Geoscience Laboratory at Université Laval (www.lgm.ggr.ulaval.ca/index.php/projets/amundsen/). The 2018 data was collected and processed by Amundsen Science (http://www.amundsen.ulaval.ca). In 2018, Amundsen Science included the multibeam bathymetry data into the Amundsen Science Data Collection.

Map Projection - A Lambert Conformal Conic projection (with two standard parallels) is used for the ArcticNet Basemap series of mapsheets. In order to minimize distortion in the areas of most interest, the standard parallels were specifically chosen to follow the two major east-west channels through the Northwest Passage (Parry Channel and Queen Maud/Coronation Gulf). The projection parameters are as follows: ¿ 1st Standard parallel: 70° ¿ 2nd Standard parallel: 73° ¿ Origin latitude: 70° ¿ Origin longitude: -105° ¿ False easting: 2,000,000 metres ¿ False northing: 2,000,000 metres Datums - Horizontal datum: NAD83; Vertical datum: soundings are reduced to mean sea level (MSL) using the WebTide tidal prediction models. Misc. Processing Details Since time is at a premium while underway, there are often cases where long transits are undertaken with little or no sound speed profiles collected. On the other hand, some oceanographic sections sampled by the Amundsen provide very dense sound speed information throughout the watercolumn. In sections where the watercolumn is poorly sampled, the 1/4 ° World Ocean Atlas (2001) climatology is used as a source of sound speed.

Geophysical data from a single-channel 3.5kHz sub-bottom profiler is acquired 24hrs during CCGS Amundsen’s cruises by a Knudsen 3260 sub-bottom profiler. The sounder is comped of 16 (4x4 array) transducers outputting a total of 10KW. The dataset consists of raw (keb and sgy) and processed (JPEG2000 and PNG images) data. Heave (TSS1 form the Applanix POS-MV) and GPS (ZDA, VTG, GGA from the CNAV GNSS Receiver) data are inputted to the raw data files directly during acquisition. The processing is made using the NRCAN software suite (SEGY to SGYJP2 and SegyJp2Viewer). The speed of sound is constantly set to 1500 m/s. The data are available in an ESRI ArcGIS geodatabase format where shiptrack lines are linked to jp2, sgy and png formats of the sub-bottom profiles.

Data were mainly collected from the CCGS Amundsen (2015 to 2019) and from the William-Kennedy (2019). An Agassiz trawl (1.5 m width × 0.7 m height, cod end of 0.5 cm mesh size) was towed on the seabed at a speed of 1.5-2 knots for 3 to 5 minutes to survey epibenthic species diversity, abundance, and biomass. Retrieved samples were washed with seawater in a sieve (2 mm mesh), and organisms were sorted and identified to the lowest taxonomical level possible. Each taxon was counted, and biomass was measured. A box corer was deployed to quantitatively sample diversity, abundance, and biomass of endobenthic organisms (macrobenthos > 0.5 mm). After retrieval of the box corer, a subsample of 0.125 m2 area and 12-15 cm depth was collected and passed through a 0.5 mm mesh sieve to separate sediment from endofauna. Organisms were immediately preserved in a 4% buffered formaldehyde solution for further taxonomical identification in the laboratory.

Accoustic data was generated from the multibeam Kongsberg Simrad EM300 (2003-2008) and EM302 (2008-2016) multibeam sonar system onboard the CCGS Amundsen during ArcticNet Cruises. This bathymetric data subset covers the Canadian Arctic and includes all CCGS Amundsen's data. The datasets consist of high-resolution bathymetry and acoustic backscatter imagery collected 24 hours a day, whenever the ship was in transit or had dedicated survey time. Standard collection settings used dual-ping, FM pulse, auto depth mode, angular coverage of +/- 60 degrees and high density equidistant beam forming. The SIS software was used to collect the data. From 2003-2013, near realtime cleaning of data outliers was done using the Ocean Mapping Group's Swathed toolkit after conversion to OMG binary format. After 2014, the data cleaning was done in the CARIS HIPS&SIPS software. Data was exported in Generic Sensor Format (.gsf). IMU data was parsed by SIS from a POSMv 320 v.4. RTG GPS data from the CNAV 3050 GNSS receiver was used to correct and improve the position output from the POSMV via a RTCM correction protocol. Soundspeed information was either from CTD Rosette casts, MVP300 data or simulated from the World Ocean Atlas 2009 database. Data are gridded at a resolution of 10 metres. Grid files available are in binary floating point file (.flt). The grids will be available shortly on the Université Laval library's geospatial center website (www.geoindex-plus.bibl.ulaval.ca/). Note: The OMG of University of New Brunswick were responsible for 2003-2013 data (www.omg.unb.ca/Projects). From 2014, responsibility switched to the Marine Geoscience Laboratory At Université Laval (www.lgm.ggr.ulaval.ca/index.php/projets/amundsen/).