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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. As part of this integrated dataset, 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, PAR-Lite) All instruments were mounted on a platform above the wheelhouse of the CCGS Amundsen

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    Floating microplastic particles were measured in surface seawater above the shelf-slope break off SW Greenland. Four replicate tows of a Manta surface trawl with 200 micron mesh were carried out from CCGS Amundsen. This site was chosen to correspond with ROV camera surveys of deep-sea corals, and to assess transportation of plastics in surface currents or from shipping. Samples were frozen for later analysis.

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    Sample collection: The sampling was part of the Canadian Arctic Shelf Exchange Study (CASES) in which CCGS Amundsen was frozen in Franklin Bay in the coastal Beaufort Sea (Station FB/200) during winter. Upper mixed-layer microbial plankton communities were sampled 5m below the water surface using the ship CTD rosette system equipped with 12L Niskins during openwater conditions. During the time that the ship was frozen in Franklin Bay from December 2003 to early June 2004, samples were taken using a 5L Niskin bottle from 3m below the bottom ice through a 300mm hole that had been drilled 500m upstream of the ship. HPLC pigment analysis: One to two liter samples of water were filtered onto Whatman GF/F filters and stored frozen at -80C until analysis. Phytoplankton pigments on the GF/Fs were extracted in 3mL of 95 percent MeOH and 100 uL of the extracts was injected into a Varian ProStar HPLC equipped with a Symmetry C8 column. The HPLC peaks were detected by diode-array spectroscopy (350-750nm) and absorbance chromatograms were obtained at 440 (for chls) and 450nm (for carotenoids). Chlorophylls were also detected by fluorescence (excitation: 440nm; emission: 650nm). The HPLC solvent protocol was based on gradient dilution with two solvent mixtures (Zapata et al. 2000): a methanol, acetonitrile, and aqueous pyridine (50:25:25 v:v:v) solution; and a methanol, acetonitrile, and acetone (20:60:20 v:v:v) solution. The flow rate was 1mL/ min, and the equilibration time was 7min.

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    Raw and post-processed precipitations were collected using a Thies Clima laser precipitation gauge. The instrument was mounted on the railing of the deck atop the bridge of the CCGS Amundsen. It should be noted that there was no good location to install the instrument, and wind eddies may have influenced the data.

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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. As part of this integrated dataset, 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, PAR-Lite) All instruments were mounted on a platform above the wheelhouse of the 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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    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.

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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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    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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    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.