Floating microplastics in Frobisher Bay were assessed using a surface trawl. Four replicate tows of a Manta surface trawl with 200 micron mesh were carried out at each of two sites in Frobisher Bay from CCGS Amundsen. Four tows near the city of Iqaluit measured microplastics contamination close to that city, likely of local origin. Four tows in outer Frobisher Bay, spread over a wider distance, measured microplastics contamination from the northern Labrador Sea or from ships traversing Frobisher Bay. Samples were frozen following collection, for later processing.

The CTD data was obtained during the 2009 Malina scientific cruise #0902 as part of the ArcticNet program. The data were collected from July 31 to August 24, 2009, aboard the CCGS Amundsen. There were 167 casts associated to 52 stations, located in the Beaufort Sea research area. The following parameters were measured: temperature, conductivity and pressure (with a Sea-Bird SBE-9plus), dissolved oxygen (Sea-Bird SBE-43), fluorescence (Seapoint chlorophyll fluorometer), CDOM (Haardt backscat fluorometer FL(RT)D), nitrate concentration (Satlantic MBARI-ISUS 5T), transmittance (Wetlabs C-Star transmissometer), currents (RDI LADCP), turbidity (UVP 5), light intensity (PAR; Biospherical Instruments QCP2300) and surface light intensity (sPAR; Biospherical Instruments QCP2200). Quality control procedures were applied to the data. Data are available on the Polar Data Catalogue and at the Marine Environmental Data Service (MEDS) of Fisheries and Oceans Canada.

During the 2007-2008 CFL IPY Project, the research icebreaker CCGS Amundsen overwintered in the South Beaufort Sea/Amundsen Gulf flaw lead system. The purpose of this experiment was to comprehensively study the flaw lead system through an entire annual cycle. As part of this project, the following radiation variables were recorded at 1 minute intervals (instrument used to collect each variable is in parentheses): -Incoming shortwave radiation (Eppley pyranometer, model PSP) -Incoming longwave radiation (Eppley pyrgeometer, model PIR) -Incoming photosynthetically active radiation (Kipp & Zonen, PARlite) -Incoming UV-A radiation (Kipp & Zonen, UVS-AB-T) - available after April 4, 2008 -Incoming UV-B radiation (Kipp & Zonen, UVS-AB-T) - available after April 4, 2008 All instruments were mounted on a platform on the wheelhouse of the CCGS Amundsen.

ArcticNet and IMG-Golder established southern and eastern Beaufort Sea Marine Observatories in 2011. The first pair of moorings (BRA and BRB) is in the southern Beaufort Sea, roughly 100 nautical miles northwest of Tuktoyaktuk. These deployments aimed at maintaining the existing ArcticNet time series initiated in 2009 in collaboration with Imperial Oil and BP. The second observatory, also deployed in 2011, consisted of two moorings (BR1 and BR2) north of the Mackenzie Trough at the western limit of the Beaufort Sea. Another pair of moorings BRG and BRK, launched in 2012 and 2014, are located off the northwest coast of Banks Island, starting a time series in the northeastern Beaufort Sea where year-round measurements have never been obtained before. Finally, two new moorings (BR3 and BR4) were also deployed at the end of the program in 2014 near BR2 and BRG respectively. For every year of deployment, each mooring line was equipped with various oceanographic instruments attached at different depths from approximately 150 m to 750 m. Moored instruments included conductivity-temperature sensors, ice profiling sonars, particle analyzers, current meters, current profilers, and sediment traps. Datasets include currents, ice draft and velocities, water levels, temperature, salinity and turbidity, chlorophyll, suspended particulate size and concentration, and vertical carbon flux; See CCIN10476 for Vertical flux data on Phyto and Zooplankton as well as on chemical parameters such as POC. Data are quality assessed/quality controlled (QA/QC) following the Climate and Forecast (CF http://cfconventions.org/) conventions and building upon the open-source Integrated Marine Observatory System (IMOS) toolbox developed for Matlab© by the Australian Ocean Data Network (AODN). The five moorings provided ready to use quality data for the period 2011-2015. BRG and BR1 time series were extended along with two moorings BR3 and BRK until 2018 during the iBO project (CCIN 13107).

Unfiltered aqueous total and methyl mercury concentrations were measured from water collection on board the NGCC/CCGS Amundsen at stations within the Beaufort Sea, Amundsen Gulf, and the Canadian Arctic Archipelago. Profiles of 10-12 m depth resolution were collected from 15 stations using the ship rosette system. Total mercury samples were analyzed on board. Methylmercury samples were preserved and transported to Winnipeg for analysis. Interpretation of results will also rely on supporting data from ArcticNet collaborators to identify water masses and determine biological productivity that determine the relative importance of external sources and internal cycling.

The Canadian research icebreaker CCGS Amundsen is equipped with an underway ThermoSalinoGraph (TSG) system, which continuously records surface seawater temperature, salinity, fluorescence and sound velocity along the transit route. Quality Assurance/Quality Control (QAQC) data are available for the summer periods between 2005 and 2020, except in 2007, 2008 and 2012 where the system was faulty or the ship was in maintenance. The TSG data were corrected and controlled by comparing them to CTD-Rosette data and in situ measures when available. Outliers and suspicious measurements were removed from the dataset. Variables are provided every 7 minutes. Research programs participating in the Amundsen expeditions between 2005 and 2020 include, ArcticNet, CFL, Geotraces, Malina, IOL and BP, BREA, Weston, Netcare, JAMSTEC, Statoil and iBO, GreenEdge, BAYSYS, Sentinel Nord (BriGHT, BOND), DFO ROV vulnerable marine ecosystem, and the Kitikmeot marine Ecosystem.

The CTD data was obtained during the 2011 ArcticNet scientific cruise #1103a. The data were collected from September 26 to October 3, 2011, aboard the CCGS Amundsen. There were 35 casts associated to 27 stations, located in Baffin Bay and the Northwest Passage. The following parameters were measured: temperature, conductivity and pressure (with a Sea-Bird SBE-9plus), dissolved oxygen (Sea-Bird SBE-43), fluorescence (Seapoint chlorophyll fluorometer), CDOM (Wetlabs FL(RT)D), nitrate concentration (Satlantic MBARI-ISUS 5T), transmittance (Wetlabs C-Star transmissometer), light intensity (PAR; LI-COR Biosciences) and surface light intensity (sPAR; LI-COR Biosciences). Quality control procedures were applied to the data. Data are available on the Polar Data Catalogue and at the Marine Environmental Data Service (MEDS) of Fisheries and Oceans Canada.

The data set includes images of seafloor topography of the Canadian Beaufort Sea, rendered in both grey-scale and colour-shaded false sun-illumination collected by the Geological Survey of Canada (Atlantic and Pacific) through the support of several organizations. The images are derived from soundings from a hull-mounted multibeam sonar system. Two research vessels were involved in its collection. The Canadian Coast Guard vessel CCGS Amundsen conducted 3 successive research-oriented field surveys, from 2009 to 2011 using a Knudsen EM302 multibeam instrument. Between September 10th and October 10th, 2013, the Korean Oceanographic Polar Research Institute (KOPRI) research icebreaker Araon surveyed with an EM122 system. The Amundsen data represent an integration of the 3 successive field surveys, data collection was a part of collaboration between oil and gas industry partners (Imperial Oil Resources/British Petroleum), the GSC-A, and ArcticNet. Collaborators from the University of New Brunswick's Ocean Mapping Group have operated the Amundsen's compliment of geophysical equipment for the past several years, extending into the 2011 Expedition. The GSC-A conducted initial and post analysis of the acquired data. The KOPRI dataset stems from collaboration with the GSC-P. Vertical sound speed profiles were obtained from CTD casting stations and these velocities were applied to the acquisition system for correct depth calculations. Geologic features in the image include large and smaller submarine landslides with associated cliffs, faults, translational blocks, retrogressive failure, debrites and evacuation chutes. Sediment cover and areas devoid of cover together with cross-cutting relationships indicate a range in age and process. Other features include mud volcanoes indicating past and recent efflux of mud and fluids to the seabed on the upper slope, iceberg, sea-ice and floating glacier-driven seabed scour, influence by currents and/or past sea-level which limited and locally removed shelf-break glacial and post-glacial muds, incision of shelf-break canyons with differential sediment infill, seabed current-influenced distribution of recent muds derived ultimately from the Mackenzie River, influence on recent distribution of shelf-break muds by the Beaufort Jet, and finally structural disturbance of outermost shelf muds, probably related to degradation of permafrost and fluid migrations, forming mounds, collapses and associated basins.

In 2017 and 2018, we sampled about 20 locations across Frobisher Bay, mostly in the deeper portions of outer Frobisher Bay that are only accessible for sampling from large ships. Sample stations were chosen to span the range of depth and slope values in the multibeam sonar dataset, and in 2018 sampling, also included gross bottom morphology, such as ridges and troughs. We also targeted some particular geomorphic features, such as suspected submarine extensions of moraines. In 2017, bottom samples were acquired using box-cores, and small scientific trawl (Agassiz trawl). In 2018, bottom samples were acquired using box-cores, combined with a drop-video camera. Agassiz trawls were collected at two stations in 2018. Sediment samples were described visually and subsamples frozen for grain size and organic content analysis. Where informative, subsamples of lithic fragments within the sediments were kept for mapping. Bottom faunal samples were enumerated and preserved in 2% formalin in seawater, except for larger faunal samples such as soft corals, which were frozen.

During the ArcticNet annual cruises of the research icebreaker CCGS Amundsen, characteristics of the near-surface atmosphere are monitored in conjunction with surface sea water properties to observe the relationship between the surface micro-climate and the air-sea exchange, with particular interest in CO2. Central to this integrated dataset is an eddy covariance system used to monitor fluxes of CO2, H2O, heat and momentum. The system continuously sampled the following variables at a rate of 10 Hz (instrument used to collect each variable is in parentheses, and approximate instrument height above surface is indicated): 3D wind velocity (Gill WindMaster Pro and Campbell Scientific CSAT3 ultra-sonic anemometers) - 15m; sonic air temperature (3D ultra-sonic anemometers) - 15m; CO2 molar concentration (two LI7500A open path gas analyzers) - 15m; H2O molar concentration (two LI7500A open path gas analyzers) - 15m; CO2 mixing ratio (LI7000 closed path system) - 15m; H2O mixing ratio (LI7000 closed path system) - 15m; and 3D ship motion - angular rates and accelerations (MotionPak, Systron Donner) - 13m. All instruments were mounted on a meteorological tower on the bow of the research icebreaker CCGS Amundsen.