Blar i Geophysical Institute på forfatter "Christensen, Kai Håkon"

Viser treff 1-11 av 11

    • A combined stokes drift profile under swell and wind sea 

      Breivik, Øyvind; Christensen, Kai Håkon (Journal article; Peer reviewed, 2020)
      A combined directional Stokes drift profile for swell and wind sea is presented. The profile can be used to calculate the shear under crossing seas and as such is relevant for Langmuir turbulence and Stokes–Coriolis forcing, ...

    • A comparison of Langmuir turbulence parameterizations and key wave effects in a numerical model of the North Atlantic and Arctic Oceans 

      Ali, Alfatih; Christensen, Kai Håkon; Breivik, Øyvind; Bertino, Laurent; Malila, Mika Petteri; Raj, Roshin Pappukutty; Chassignet, Eric P.; Bakhoday Paskyabi, Mostafa (Peer reviewed; Journal article, 2019)
      Five different parameterizations of Langmuir turbulence (LT) effect are investigated in a realistic model of the North Atlantic and Arctic using realistic wave forcing from a global wave hindcast. The parameterizations ...

    • Constraining energetic slope currents through assimilation of high-frequency radar observations 

      Sperrevik, Ann Kristin; Christensen, Kai Håkon; Röhrs, Johannes (Peer reviewed; Journal article, 2015-03-11)
      Assimilation of high-frequency (HF) radar current observations and CTD hydrography is performed with the 4D-Var analysis scheme implemented in the Regional Ocean Modeling System (ROMS). We consider both an idealized case, ...

    • Current shear and turbulence during a near-inertial wave 

      Röhrs, Johannes; Halsne, Trygve; Sutherland, Graig; Dagestad, Knut-Frode; Hole, Lars Robert; Brostrøm, Gøran; Christensen, Kai Håkon (Journal article; Peer reviewed, 2023-04-11)
      Surface currents and turbulent mixing were observed during a near-inertial wave (NIW) using an accousting doppler current profiler (ADCP) and satellite-tracked drifters. Drifter trajectories sampled at three depth levels ...

    • A dataset of direct observations of sea ice drift and waves in ice 

      Rabault, Jean; Müller, Malte; Voermans, Joey; Brazhnikov, Dmitry; Turnbull, Ian; Marchenko, Aleksey; Biuw, Martin; Nose, Takehiko; Waseda, Takuji; Johansson, Malin; Breivik, Øyvind; Sutherland, Graig; Hole, Lars Robert; Johnson, Mark; Jensen, Atle; Gundersen, Olav; Kristoffersen, Yngve; Babanin, Alexander; Tedesco, Paulina Souza; Christensen, Kai Håkon; Kristiansen, Martin; Hope, Gaute; Kodaira, Tsubasa; Martins de Aguiar, Victor Cesar; Taelman, Catherine Cecilia A; Quigley, Cornelius Patrick; Filchuk, Kirill; Mahoney, Andrew R. (Journal article; Peer reviewed, 2023)
      Variability in sea ice conditions, combined with strong couplings to the atmosphere and the ocean, lead to a broad range of complex sea ice dynamics. More in-situ measurements are needed to better identify the phenomena ...

    • Evaluating the leeway coefficient of ocean drifters using operational marine environmental prediction systems 

      Sutherland, Graig; Soontiens, Nancy; Davidson, Fraser; Smith, Gregory C.; Bernier, Natacha; Blanken, Hauke; Schillinger, Douglas; Marcotte, Guillaume; Röhrs, Johannes; Dagestad, Knut-Frode; Christensen, Kai Håkon; Breivik, Øyvind (Journal article; Peer reviewed, 2020)
      The water following characteristics of six different drifter types are investigated using two different operational marine environmental prediction systems: one produced by Environment and Climate Change Canada (ECCC) and ...

    • Impact of data assimilation on Eulerian versus Lagrangian estimates of upper ocean transport 

      Sperrevik, Ann Kristin; Röhrs, Johannes; Christensen, Kai Håkon (Peer reviewed; Journal article, 2017)
      Using four-dimensional variational analysis, we produce an estimate of the state of a coastal region in Northern Norway during the late winter and spring in 1984. We use satellite sea surface temperature and in situ ...

    • Long-Term Statistics of Observed Bubble Depth Versus Modeled Wave Dissipation 

      Strand, Kjersti Opstad; Breivik, Øyvind; Pedersen, Geir; Vikebø, Frode Bendiksen; Sundby, Svein; Christensen, Kai Håkon (Journal article; Peer reviewed, 2020)
      Air bubble penetration depths are investigated with a bottom‐mounted echosounder at a seabed observatory in northern Norway. We compare a 1‐year time series of observed bubble depth against modeled and estimated turbulent ...

    • Modelling alongshore flow in a semi-enclosed lagoon strongly forced by tides and waves 

      Taskjelle, Torbjørn; Barthel, Knut; Christensen, Kai Håkon; Furaca, Noca; Gammelsrød, Tor; Hoguane, Antonio Mubango; Nharreluga, Bilardo (Peer reviewed; Journal article, 2014-09-26)
      Alongshore flows strongly driven by tides and waves is studied in the context of a one-dimensional numerical model. Observations from field surveys performed in a semi-enclosed lagoon (1.7 km×0.2 km) outside Xai-Xai, ...

    • Resolving regions known for intense wave–current interaction using spectral wave models: A case study in the energetic flow fields of Northern Norway 

      Halsne, Trygve; Bohlinger, Patrik; Christensen, Kai Håkon; Carrasco, Ana; Breivik, Øyvind (Journal article; Peer reviewed, 2022)
      Oceanic current forcing in spectral wave models have recently been demonstrated to have a large impact on wave heights at scales between one and up to several hundred kilometers. Here we investigate the impact of such ...

    • The "shallow-waterness" of the wave climate in European coastal regions 

      Christensen, Kai Håkon; Carrasco, Ana; Bidlot, Jean-Raymond; Breivik, Øyvind (Peer reviewed; Journal article, 2017-07-20)
      In contrast to deep water waves, shallow water waves are influenced by bottom topography, which has consequences for the propagation of wave energy as well as for the energy and momentum exchange between the waves and the ...