The distribution of dissolved organic carbon (DOC) in the water column of the Canadian High Arctic was investigated in 2006, as part of the ArcticNet program. Summer-fall DOC concentrations were measured at 27 stations between 4 September and 17 October 2006. Samples were collected using the rosette onboard the CCGS Amundsen. Euphotic zone sampling depths corresponded to surface irradiances between 0.2 and 100% as well as the chlorophyll a maximum depth. Aphotic sampling depths ranged from 75 m to the bottom waters.

Samples were collected at 5 sites ranging in water depth from 100 to 595 m at least once in each season (ice-covered and open-water condition) between March and August 2008 onboard the icebreaker CCGS Amundsen. At each sampling station, an USNEL box corer was deployed for collecting seafloor sediments. From each box core, 5 sub-cores of 11 cm diameter and 20 cm sediment depth were taken for assessing benthic carbon remineralisation in microcosm incubations and 3 additional subcores of 5 cm diameter and 10 cm length were taken for determining sediment properties. Incubations of sediment microcosms were run in a dark, temperature-controlled room (2-4 °C) for 24-48 h. Each sediment microcosm was sieved through a 0.5 mm mesh under running sea water at the end of incubations to determine biomass of macrofaunal communities. The sieve residue was preserved in a buffered 4% seawater-formaldehyde solution and analysed for species composition and abundance under a stereomicroscope in the lab.

Zooplankton samples were collected onboard the research Icebreaker CCGS Amundsen during Leg 1 in 2005 (4 stations) and Leg 1 in 2006 (8 stations) with a vertically towed net frame equipped with a set of 4 adjacent 1-m2 nets (mesh size 200 µm and 500 µm) from near the bottom to the surface and by trawling an oblique rectangular mid-water trawl (mesh size 1600 µm) or an oblique Tucker net (mesh size 2x500 µm) in the surface layer from 100 m depth to the surface. Samples were placed into 30 ml plastic vials and/or whirl-pak bags and were kept frozen at -20 degree Celsius. Representative sub-samples of individual zooplankton genera were placed in 4 ml glass vials for stable isotope analysis. Three keystone zooplankton genus were included in this study: Calanus spp. (mostly adult Calanus hyperboreus), Themisto spp. (mostly adult Themisto libellula) and Euchaeta spp. THg analysis was conducted at the Freshwater Institute with cold vapour atomic absorption spectroscopy (CVAAS). MMHg analysis was conducted at the University of Ottawa by Gas Chromatography Atomic Fluorescence Spectroscopy (GCAFS). Carbon and nitrogen isotopic analyses were performed at the University of Winnipeg Isotope Laboratory by continuous flow ion ratio mass spectrometry (CF-IRMS). Oceanographic data (Hg levels in water column, salinity, 18O) were collected by our team. Water samples were collected with 24 12-L Niskin bottles attached to a rosette sampler equipped with Seabird 911+ CTD (Sea-Bird Electronics, Inc.).

Sinking export of organic material was investigated during the fall of 2007, using free-drifting, short-term particle interceptor traps . The particle interceptor traps were deployed at 6 stations along a transect spanning between the North Water polynya (Baffin Bay) and the Beaufort Sea. The traps were deployed from the CCGS Amundsen at three depths below the euphotic zone (50, 100 and 150 m) for a period between 8 and 22 hours. The analyses on the sinking material included total chlorophyll a and phaopigments (fluorometric determination), particulate organic carbon and nitrogen, biogenic silica, cell composition and abundance and fecal pellet abundance.

The distribution of dissolved organic carbon (DOC) in the water column of the Canadian Arctic was investigated in 2007, as part of the ArcticNet program. Summer-fall DOC concentrations were measured at 30 stations between 29 September and 3 November 2007. Samples were collected using the rosette onboard the CCGS Amundsen. Euphotic zone sampling depths corresponded to surface irradiances between 0.2 and 100% as well as the chlorophyll a maximum depth. Aphotic sampling depths ranged from 75 m to the bottom waters.

The study area extends from the North Water Polynya to the Chukchi Sea across five geographic regions: North Water Polynya, Canadian Archipelago, Amundsen Gulf, Beaufort Sea and Chukchi Sea (14 stations). We collected data from July to October 2014 aboard the CCGS Amundsen including environmental data (bottom water temperature and salinity), particulate organic matter, sediments, and benthos. Stable isotopes analyses were practiced on benthic samples, particulate organic matter samples and sediments samples. Lipid extraction and ice algae biomarker analysis were practiced on benthic samples and sediments samples.

The CTD data was obtained during LEG 01 of the 2003 CASES scientific cruise #0303. This Leg was carried out from September 8th 2003 to October 15th 2003 aboard the CCGS Amundsen. There were 37 CTD casts in Leg 1. One cast, associated to 1 oceanographic station, is located in the Northern Baffin Bay research area. The following parameters were measured: temperature, conductivity and pressure (with a Sea-Bird 911 probe), oxygen (Sea-Bird 43), fluorescence (Seapoint fluorometer), transmittance (Wetlabs C-Star transmissometer). There are two different versions of the CTD data file. A version containing processed data that was sent to the NIs and the original version containing all the data and metadata that were quality controlled. The first version of the data file is hosted on the ArcticNet FTP site and the second version is hosted by the Marine Environmental Data Service (MEDS) of Fisheries and Ocean Canada ans the Polar Data Catalogue.

The CTD data was obtained during the 2005 ArcticNet scientific cruise #0501. The data were collected from August 14 to 23, 2005, aboard the CCGS Amundsen. There were 54 casts, associated to 36 oceanographic stations, in the Northern Baffin Bay. The following parameters were measured: temperature, conductivity and pressure (with a Sea-Bird SBE-9plus), dissolved oxygen (Sea-Bird SBE-43), pH (Sea-Bird SBE-18-I), fluorescence (Seapoint chlorophyll fluorometer), nitrate concentration (Satlantic MBARI-ISUS 5T), transmittance (Wetlabs C-Star transmissometer), 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.

The CTD data was obtained during leg #0602 of the 2006 ArcticNet scientific cruise. The data were collected from September 4 to 20, 2006, aboard the CCGS Amundsen. There were 72 casts, associated to 39 oceanographic stations, in the Northern Baffin Bay research area. The following parameters were measured: temperature, conductivity and pressure (with a Sea-Bird SBE-9plus), dissolved oxygen (Sea-Bird SBE-43), pH (Sea-Bird SBE-18-I), fluorescence (Seapoint chlorophyll fluorometer), nitrate concentration (Satlantic MBARI-ISUS 5T), transmittance (Wetlabs C-Star transmissiometer), 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.

Sinking export of organic material was investigated during the fall of 2006, using free-drifting, short-term particle interceptor traps . The particle interceptor traps were deployed at 9 stations along a transect spanning between the North Water polynya (Baffin Bay) and the Beaufort Sea. The traps were deployed from the CCGS Amundsen at three depths below the euphotic zone (50, 100 and 150 m) for a period between 8 and 29 hours. The analyses on the sinking material included total chlorophyll a and phaopigments (fluorometric determination), particulate organic carbon and nitrogen, biogenic silica, cell composition and abundance and fecal pellet abundance.