From 1 - 10 / 287
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    Raw data collected using a creative webcam and an acryllic hemispherical mirror dome installed on the roof of the wheelhouse of the CCGS Amundsen. Data were collected from summer to fall 2009 in the Southern Beaufort Sea and Amundsen Gulf areas.

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    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.

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    This study presents sea surface concentrations of marine dimethylsulfide (DMS) measured across the Labrador Sea and the Canadian Arctic Archipelago during summer of 2017 (July-August). Using a novel automated instrument (ACT-MIMS) more than 2500 DMS observations were collected at high frequency alongside ancillary measurements of salinity, temperature, fluorescence (chlorophyll a proxy), solar radiation, ice concentration and the algal precursor of DMS, dimethylsulfoniopropionate. DMS concentrations ranged from ca. 1 to 32 nmol L-1 (average of 6 nmol L-1) in 2017 over an area covering a wide range of contrasting marine environments from coastal to open ocean, ice-free waters, as well as under-ice waters. Surface water DMS hotspots were measured in association with thermohaline oceanographic features in high productivity coastal waters, as well as with the presence of ponded first-year ice (FYI). Nighttime increases and daytime decreases of DMS concentrations were also observed in productive areas of the Labrador Sea and Davis Strait continental shelf. The association of DMS concentrations with diurnal solar radiation variation suggests the involvement of photobiological processes. Overall, our results strengthen the view that aqueous DMS cycling in the Arctic is intimately linked with sea ice dynamics and physiological responses to light. As such, future changes in the seasonality of the Arctic cryosphere will likely play an important role in shaping DMS emissions, although the sign and magnitude of the change remain highly uncertain.

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    During the ArcticNet annual cruises of the research icebreaker CCGS Amundsen, characteristics of the near-surface atmosphere (basic meteorological elements, incident radiation, CO2 concentration) are monitored in conjunction with surface sea water properties (temperature, salinity, dissolved CO2 and O2) to observe the relationship between the surface micro-climate and the air-sea exchange, with particular interest in CO2. Central to this integrated dataset, the following meteorological variables were recorded at 1 minute intervals (instrument used to collect each variable is in parentheses, and approximate instrument height above surface is indicated): -Wind speed (RM Young Wind Monitor 05103) - 16m height -Wind direction (RM Young Wind Monitor 05103) -16m height -Air Temperature (Vaisala HMP45C212) - 15m height -Relative Humidity (Vaisala HMP45C212) -15m height -Surface temperature (Everest IR Transducer, 4000.44ZL) - 8m height All instruments were mounted on a meteorological tower on the bow of the research icebreaker CCGS Amundsen.

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    The Belcher Glacier seabed mapping program was carried out over a 12-hour period in September 2006 and consisted of: 1) imaging of deeper parts of the inlet using the EM300 30 kHz multibeam sonar on the CCGS Amundsen icebreaker; and 2) detailed mapping adjacent to the tidewater front using the 300 kHz multibeam launch CSL Heron. Data files from this mapping project are archived in ASCII, ESRI, and GTIF formats."

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    Onshore research was conducted using the following methods: multi-temporal analysis and mapping of modern and raised coastal systems using airphotos, satellite imagery, LiDAR and RTK GPS surveys. Data on the sediment composition of coastal landforms was collected using graded photographs and in situ measurments of gravel samples. Shallow-water mapping of transgressive coastal systems was carried out using multibeam sonar and sub-bottom profiler primarily from the CCGS Amundsen (EM300 30 kHz) and the CSL Heron (EM3002 3.5 kHz) during the 2006 ArcticNet NCE scientific cruise and from the CCGS Henry Larsen and the CSL Heron in 2008.

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    During the ArcticNet annual cruises of the research icebreaker CCGS Amundsen, characteristics of the near-surface atmosphere (basic meteorological elements, incident radiation, CO2 concentration) are monitored in conjunction with surface sea water properties (temperature, salinity, dissolved CO2 and O2) to observe the relationship between the surface micro-climate and the air-sea exchange, with particular interest in CO2. Central to this integrated dataset, the following meteorological variables were recorded at 1 minute intervals (instrument used to collect each variable is in parentheses, and approximate instrument height above surface is indicated): -Wind speed (RM Young Wind Monitor 05103) - 16m height -Wind direction (RM Young Wind Monitor 05103) -16m height -Air Temperature (Vaisala HMP45C212) - 15m height -Relative Humidity (Vaisala HMP45C212) -15m height -Surface temperature (Everest IR Transducer, 4000.44ZL) - 8m height All instruments were mounted on a meteorological tower on the bow of the research icebreaker CCGS Amundsen.

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    Processed atmospheric ceiling heights were recorded from a CT25K ceilometer. The instrument was mounted on the CCGS Amundsen icebreaker on the port side directly behind the ship's wheelhouse. Data were collected during transit, set transects, 24-hour stations, and multi-day drift stations. The instrument was running continuously during the IPY-CFL project, with only minor interruptions for maintenance activities.

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    Onshore research was conducted using the following methods: multi-temporal analysis and mapping of modern and raised coastal systems using airphotos, satellite imagery, LiDAR and RTK surveys. Data on the sediment composition of coastal landforms was collected using graded photographs. Shallow-water mapping of transgressive coastal systems was carried out using multibeam sonar and sub-bottom profiler primarily from the CCGS Amundsen and the CSL Heron during the 2006 ArcticNet NCE scientific cruise.

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    The data set is composed of raw files recorded with the Kongsberg Maritime SX90 long-range, low frequency (20-30 kHz) fisheries sonar during the CCGS Amundsen 2011 summer expedition in the Eastern Canadian Arctic. The sonar was operated during a 3 hours opportunistic survey offshore the Labrador coast on July 22nd and during a 18.75 hours opportunistic survey on July 30th. The sonar transducer is lowered 2.5 feet below the hull through a gate-valve. The cylindrical 256-elements transducer allows both a horizontal and a vertical sound transmission, and the omni-directional (horizontal) sonar beam can be tilted from +10 to -60 degrees to scan a large portion of the water column. The raw acoustic data were saved onto an external drive and print screens of interesting targets (fish schools and/or marine mammals) were recorded.