Blar i forfatter "Wiktor, Josef"

Viser treff 1-4 av 4

    • Arctic Observations Identify Phytoplankton Community Composition as Driver of Carbon Flux Attenuation 

      Wiedmann, Ingrid; Ceballos-Romero, E.; Villa-Alfageme, M.; Renner, Angelika; Dybwad, Christine; van der Jagt, Helga; Svensen, Camilla; Assmy, Philipp; Wiktor, Josef; Tatarek, Agnieszka; Różańska‐Pluta, M.; Iversen, Morten H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-24)
      The attenuation coefficient <i>b</i> is one of the most common ways to describe how strong the carbon flux is attenuated throughout the water column. Therefore, <i>b</i> is an essential input variable in many carbon flux and climate models. Marsay et al. (2015, <a href=https://doi.org/10.1073/pnas.1415311112>https://doi.org/10.1073/pnas.1415311112</a>) proposed that the median surface water temperature ...

    • Floating Ice-Algal Aggregates below melting Arctic Sea Ice 

      Assmy, P; Ehn, Jens K.; Fernandez-Mendez, M; Hop, H; Katlein, C; Sundfjord, Arild; Bluhm, K; Daase, Malin; Engel, A.; Fransson, A.; Granskog, M.A.; Hudson, SR; Kristiansen, Svein; Nicolaus, M.; Peeken, I.; Renner, AHH; Spreen, Gunnar; Tatarek, Agnieszka; Wiktor, Josef (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      During two consecutive cruises to the Eastern Central Arctic in late summer 2012, we observed floating algal aggregates in the melt-water layer below and between melting ice floes of first-year pack ice. The macroscopic (1-15 cm in diameter) aggregates had a mucous consistency and were dominated by typical ice-associated pennate diatoms embedded within the mucous matrix. Aggregates maintained ...

    • Leads in Arctic pack ice enable early phytoplankton blooms below snow-covered sea ic 

      Assmy, Philipp; Fernández-Méndez, Mar; Duarte, Pedro; Meyer, Amelie; Randelhoff, Achim; Mundy, Christopher John; Olsen, Lasse; Kauko, Hanna M.; Bailey, Allison; Chierici, Melissa; Cohen, Lana; Doulgeris, Anthony Paul; Ehn, Jens K.; Fransson, Agneta; Gerland, Sebastian; Hop, Haakon; Hudson, Stephen R.; Hughes, Nick; Itkin, Polona; Johnsen, Geir; King, Jennifer A.; Koch, Boris P.; Koenig, Zoe; Kwasniewski, Slawomir; Laney, Samuel R.; Nikolaus, Marcel; Pavlov, Alexey K.; Polashenski, Christopher M.; Provost, Christine; Rösel, Anja; Sandbu, Marthe; Spreen, Gunnar; Smedsrud, Lars H.; Sundfjord, Arild; Taskjelle, Torbjørn; Tatarek, Agnieszka; Wiktor, Josef; Wagner, Penelope Mae; Wold, Anette; Steen, Harald; Granskog, Mats A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-01-19)
      The Arctic icescape is rapidly transforming from a thicker multiyear ice cover to a thinner and largely seasonal first-year ice cover with significant consequences for Arctic primary production. One critical challenge is to understand how productivity will change within the next decades. Recent studies have reported extensive phytoplankton blooms beneath ponded sea ice during summer, indicating ...

    • The seeding of ice algal blooms in Arctic pack ice: The multiyear ice seed repository hypothesis 

      Olsen, Lasse Mork; Laney, Samuel R.; Duarte, Pedro; Kauko, Hanna M.; Fernández-Méndez, Mar; Mundy, Christopher John; Rösel, Anja; Meyer, Amelie; Itkin, Polona; Cohen, Lana; Peeken, Ilka; Tatarek, Agnieszka; Róźańska-Pluta, Magdalena; Wiktor, Josef; Taskjelle, Torbjørn; Pavlov, Alexey; Hudson, Stephen R.; Granskog, Mats A.; Hop, Haakon; Assmy, Philipp (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-03)
      During the Norwegian young sea ICE expedition (N-ICE2015) from January to June 2015 the pack ice in the Arctic Ocean north of Svalbard was studied during four drifts between 83° and 80°N. This pack ice consisted of a mix of second year, fi rst year, and young ice. The physical properties and ice algal community composition was investigated in the three different ice types during the ...