Search Results - "Christensen, Kai H"

A two layer model for wave dissipation in sea ice by Sutherland, Graig, Rabault, Jean, Christensen, Kai H., Jensen, Atle

“…Sea ice is highly complex due to the inhomogeneity of the physical properties (e.g. temperature and salinity) as well as the permeability and mixture of water…”
Get full text

Evaluation of Selected Finite-Difference and Finite-Volume Approaches to Rotational Shallow-Water Flow by Holm, H. H., Brodtkorb, A. R., Broström, Göran, Christensen, K. H., Saetra, M. L.

“…The shallow-water equations in a rotating frame of reference are important for capturing geophysical flows in the ocean. In this paper, we examine and compare…”
Get full text

Comparison between a multi-variate nudging method and the ensemble Kalman filter for sea-ice data assimilation by FRITZNER, SINDRE M., GRAVERSEN, RUNE G., WANG, KEGUANG, CHRISTENSEN, KAI H.

“…Increasing ship traffic and human activity in the Arctic has led to a growing demand for accurate Arctic weather forecast. High-quality forecasts obtained by…”
Get full text

Current shear and turbulence during a near-inertial wave by Röhrs, Johannes, Halsne, Trygve, Sutherland, Graig, Dagestad, Knut-Frode, Hole, Lars Robert, Broström, Göran, Christensen, Kai H.

“…Surface currents and turbulent mixing were observed during a near-inertial wave (NIW) using an accousting doppler current profiler (ADCP) and satellite-tracked…”
Get full text

Drift in the uppermost part of the ocean by Röhrs, Johannes, Christensen, Kai H.

“…Lagrangian drift velocities within the uppermost meter of the ocean mostly depend on the local wind forcing, turbulent mixing, and waves. While the interior…”
Get full text

Measurements of Waves in Landfast Ice Using Inertial Motion Units by Rabault, Jean, Sutherland, Graig, Ward, Brian, Christensen, Kai H., Halsne, Trygve, Jensen, Atle

“…Inertial motion units (IMUs) are used to perform measurements of waves in water covered by landfast ice close to the ice edge in Svalbard. The effective noise…”
Get full text

Improved representation of vertical (T,S) profiles using real-time assimilation in Arctic waters by Ostenstad, Petter, Brandshoi, Jostein, Christensen, Kai H.

“…Realistic description of vertical sound speed profiles are essential for underwater acoustic modelling. Sound speed profiles are usually derived from vertical…”
Get full text

Short-Term Predictions of OCEANIC DRIFT by Christensen, Kai H., Breivik, Øyvind, Dagestad, Knut-Frode, Röhrs, Johannes, Ward, Brian

“…We discuss oceanic drift as relevant to applications in operational oceanography using examples from recent field experiments to highlight some of the…”
Get full text

Impact of assimilating sea ice concentration, sea ice thickness and snow depth in a coupled ocean–sea ice modelling system by Fritzner, Sindre, Graversen, Rune, Christensen, Kai H, Rostosky, Philip, Wang, Keguang

“…The accuracy of the initial state is very important for the quality of a forecast, and data assimilation is crucial for obtaining the best-possible initial…”
Get full text

Assessment of High‐Resolution Dynamical and Machine Learning Models for Prediction of Sea Ice Concentration in a Regional Application by Fritzner, Sindre, Graversen, Rune, Christensen, Kai H.

“…In this study, the potential for sea ice concentration prediction using machine‐learning methods is investigated. Three different sea ice prediction models are…”
Get full text

Wave measurements from ship mounted sensors in the Arctic marginal ice zone by Løken, Trygve K., Rabault, Jean, Jensen, Atle, Sutherland, Graig, Christensen, Kai H., Müller, Malte

“…This study presents wave measurements in the Marginal Ice Zone (MIZ) obtained from ship mounted sensors. The system combines altimeter readings from the ship…”
Get full text

Virtual wave stress and transient mean drift in spatially damped long interfacial waves by Weber, Jan Erik H., Christensen, Kai H.

“…The mean drift in spatially damped long gravity waves at the boundary between two layers of immiscible viscous fluids is investigated theoretically by applying…”
Get full text

Barents-2.5km v2.0: an operational data-assimilative coupled ocean and sea ice ensemble prediction model for the Barents Sea and Svalbard by Röhrs, Johannes, Gusdal, Yvonne, Rikardsen, Edel S. U, Durán Moro, Marina, Brændshøi, Jostein, Kristensen, Nils Melsom, Fritzner, Sindre, Wang, Keguang, Sperrevik, Ann Kristin, Idžanovic, Martina, Lavergne, Thomas, Debernard, Jens Boldingh, Christensen, Kai H

“…An operational ocean and sea ice forecast model, Barents-2.5, is implemented for short-term forecasting at the coast off northern Norway, the Barents Sea, and…”
Get full text

On the analogy between rigid plate motion and mean momentum transfer in surface gravity waves by Weber, Jan Erik H., Christensen, Kai H.

“…The transfer of mean momentum from surface gravity waves to Eulerian mean fluxes is investigated by modeling the total wave momentum (the Stokes flux) as a…”
Get full text

Modelling alongshore flow in a semi-enclosed lagoon strongly forced by tides and waves by Taskjelle, Torbjørn, Barthel, Knut, Christensen, Kai H., Furaca, Noca, Gammelsrød, Tor, Hoguane, António M., Nharreluga, Bilardo

“…Alongshore flows strongly driven by tides and waves is studied in the context of a one-dimensional numerical model. Observations from field surveys performed…”
Get full text

Note on Coriolis-Stokes force and energy by Broström, Göran, Christensen, Kai H., Drivdal, Magnus, Weber, Jan Erik H.

“…In this study, we consider the origin of the Coriolis-Stokes (CS) force in the wave-averaged momentum and energy equations and make a short analysis of…”
Get full text

Some aspects of the Coriolis-Stokes forcing in the oceanic momentum and energy budgets by Weber, Jan Erik H., Drivdal, Magnus, Christensen, Kai H., Broström, Göran

“…The Coriolis‐Stokes (CS) force is a wave‐induced forcing of the Eulerian mean motion in a rotating ocean. For idealized conditions, it is demonstrated by…”
Get full text

On the singular behavior of the Stokes drift in layered miscible fluids by Weber, Jan Erik H., Christensen, Kai H.

“…Gravity waves of the Stokes-type in a system of two horizontal layers of inviscid, stratified and miscible fluids are studied by applying a Lagrangian…”
Get full text

Wave measurements using open source ship mounted ultrasonic altimeter and motion correction system during the one ocean circumnavigation by Ølberg, Judith Thu, Bohlinger, Patrik, Breivik, Øyvind, Christensen, Kai H., Furevik, Birgitte R., Hole, Lars R., Hope, Gaute, Jensen, Atle, Knoblauch, Fabian, Nguyen, Ngoc-Thanh, Rabault, Jean

“…This study reviews the design and signal processing of ship borne ultrasonic altimeter wave measurements. The system combines a downward facing ultrasonic…”
Get full text

A comparison of Langmuir turbulence parameterizations and key wave effects in a numerical model of the North Atlantic and Arctic Oceans by Ali, Alfatih, Christensen, Kai H., Breivik, Øyvind, Malila, Mika, Raj, Roshin P., Bertino, Laurent, Chassignet, Eric P., Bakhoday-Paskyabi, Mostafa

“…Five different parameterizations of Langmuir turbulence (LT) effect are investigated in a realistic model of the North Atlantic and Arctic using realistic wave…”
Get full text