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    Genelal description: Ice cores, samples of nilas and snow samples, under-ice water and a sample of frost flowers were taken in the Amundsen Gulf (Canadian Arctic) onboard the CCGS Amundsen. Methology: We used corer to collect ice cores and frost flowers and we used ice cage to collect nilas. We collected descriptive variables for the snow and frost flowers, ice cores and nilas, and for under ice water. For all samples, we measured pH, salinity and conductivity. Back in our university-based laboratories, we studied elemental composition of samples and we carried out scanning electron microscopy.

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    Microplastics pollution has been found across the globe, but with limited information from the polar regions. Although there is evidence of microplastics in the Arctic and Antarctic, little is understood about the sources, fate and extent of contamination. We collected samples and will quantify the amount and identify the types of microplastics in snow, ice, water, sediments and zooplankton sampled from the CCGS Amundsen in and around the Hudson Bay and/or the central and eastern Canadian Archipelago. In addition, we will answer questions about sources and fate using two types of information. We will examine patterns of microplastics contamination and compare them with land-use patterns and water and air circulation. Based on previous studies, and our preliminary findings, we believe that microplastics will be present in Arctic samples, but a detailed study will help us better understand how ubiquitous microplastics are, from where they are derived, and how they are preserved or degraded. Microplastics in the Arctic raise concerns about impacts to wildlife and local communities that rely on food from the sea. Results from this study will inform future experiments that answer questions related to such impacts.

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    The Arctic Ocean in summer is thought to be a nexus of biogenic dimethylsulfide (DMS) production associated, in part, with diversified niches within or bordering dynamic sea-ice where DMS-rich microbial communities may thrive. However, critical uncertainties remain regarding the strength of sources, sinks and efflux of marine DMS in the Arctic. Quantifying contemporary oceanic reservoirs of DMS is pivotal for the prediction and interpretation of future reservoirs of this climate-active compound. While a global DMS database of ca. 50,000 points exists, only 2.5% of these inputs originate from Arctic oceans highlighting the relevance of continued sampling efforts particularly in the context of rapid and conspicuous climate alterations in this part of the Global Ocean. A joint NETCARE-ArcticNet campaign aboard the CCGS Amundsen during July and August 2016 served as the launching platform for the deployment of a high frequency autonomous underway DMS sampling instrument (MIMS – Membrane Inlet Mass Spectrometer). Providing real-time data, the MIMS allowed the detection of surface reservoirs of oceanic DMS at greater spatial and temporal scales than traditional single-sample gas chromatography analysis, in conjunction with measurements of temperature, salinity and fluorescence (water line TSG sensor)

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    Improved surface and bedrock DEMs have been produced for the Belcher Glacier using data from different sources, including in situ measurements, airborne soundings, and satellite images. Surface elevation is based on 2007 (late summer) SPOT5 HRS images. Bed elevation values are derived from surface-based ground penetrating radar soundings conducted during the 2007 and 2008 summer field seasons. Airborne radar surveys in 2000 and 2005 by the Scott Polar Research Institute and the Center for Remote Sensing of Ice Sheets, respectively, provide ice thickness data. By subtracting ice thickness from surface elevation using the surface DEM, bedrock elevation values are derived. Additional bedrock elevation data for the seafloor in front of the terminus of Belcher Glacier were obtained from a bathymetric survey in 2006 by workers from Memorial University of Newfoundland and the University of New Brunswick working off the CCGS Amundsen. A 40-m grid is used as a map base. Bed elevation values were found for each point on the grid by applying a kernel that weighted values of surrounding points by distance. After finding a suitable semivariogram model, statistical interpolation (kriging) was performed to fill in the rest of the grid points to produce the bedrock DEM. As a check, a 1999 Landsat panchromatic image was used to force bedrock elevation to equal surface elevation within the boundaries of rock outcrops and thus ensure that ice thickness is zero throughout.

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    First-year sea ice was sampled on 36 occasions near the overwintering site of the CCGS Amundsen during the Canadian Arctic Shelf Exchange Study (CASES). Sea-ice and associated surface water samples were taken every 3 to 5 days between 24 February and 20 June 2004. Surface waters and the bottom 3-5 cm of ice cores were routinely analyzed for: salinity, pH, nutrients (NH4, NO2, NO3, Si(OH)4, and PO4), dissolved organic carbon and nitrogen (DOC, DON), exopolymeric substances (EPS), particulate inorganic carbon (PIC), particulate organic carbon and nitrogen (POC, PON), total and >5 µm chlorophyll a and phaeopigments, bacterial abundances/biomass, protist (excluding diatoms) abundances/biomass and ice algal/phytoplankton taxonomy. This data set also includes vertical and spatial profiles of ice algal distribution as well as measurements of sea-ice primary production, bacterivory and sea-ice algal and bacterial sinking velocities.