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.

The CTD data was obtained during the 2009 ArcticNet scientific cruise #0903 with the participation of Imperial Oil Ltd. (IOL). The data were collected from September 14 to October 4, 2009, aboard the CCGS Amundsen. There were 31 casts associated to 31 stations, located in the Beaufort Sea 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.

The CTD data was obtained during the 2010 ArcticNet scientific cruise #1002b in collaboration with the industrial partner BP. The data were collected from September 2 to 23, 2010, aboard the CCGS Amundsen. There were 10 casts associated to 9 stations, located in the Beaufort Sea. 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; 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 #0603 of the 2006 ArcticNet scientific cruise. The data were collected from October 28 to November 4, 2006, aboard the CCGS Amundsen. There were 22 casts, associated to 21 oceanographic stations, in the Labrador Sea and its fjords along the Canadian coast. 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.

The CTD data was obtained during leg #0603 of the 2006 ArcticNet scientific cruise. The data were collected from September 29 to 30 and from October 19 to 25, 2006, aboard the CCGS Amundsen. There were 31 casts, associated to 22 oceanographic stations, in the Northwest Passage 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.

The CTD data was obtained during the 2009 Geotraces scientific cruise #0903 as part of the ArcticNet program. The data were collected from August 30 to September 10, 2009, aboard the CCGS Amundsen. There were 45 casts associated to 8 stations, located in the Beaufort Sea 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.

The CTD data was obtained during the 2007-2008 scientific cruise #0707 within the framework of the Circumpolar Flaw Lead Study (CFL). This program included a year round sampling expedition to study the air-sea interactions occurring in the ice-free sections of the southern Beaufort Sea and Amundsen Gulf. The data were collected from November 10 to December 18, 2007, aboard the CCGS Amundsen. There were 105 casts, associated to 16 oceanographic stations, in the Beaufort Sea 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 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 the 2010 ArcticNet scientific cruise #1003a. The data were collected from September 24 to October 7, 2010, aboard the CCGS Amundsen. There were 19 casts associated to 14 stations, located in the Beaufort Sea. 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; 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 09 of the 2004 CASES scientific cruise #0406. This Leg was carried out from August 5th 2004 to August 26th 2004 aboard the CCGS Amundsen. There were 24 CTD casts in Leg 9. Twenty casts, associated to 5 oceanographic stations, are located in the Beaufort sea research area. The following parameters were measured: temperature, conductivity and pressure (with a Sea-Bird 911 probe), oxygen (Sea-Bird 43), pH (Seabird 18), fluorescence (Seapoint fluorometer), nitrates (Satlantic MBARI ISUS), transmittance (Wetlabs C-Star transmissometer), PAR/Irradiance and SPAR/Irradiance (Biospherical Instruments QC2300). Data were quality controlled. Data are available on the Polar Data Catalogue and at the Marine Environmental Data Service (MEDS) of Fisheries and Ocean Canada.

The CTD data was obtained during the 2010 ArcticNet scientific cruise #1001b. The data were collected from August 7 to 11, 2010, aboard the CCGS Amundsen. There were 12 casts associated to 8 stations, located in the Eastern Part of 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; 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.