Ocean Dynamics

, Volume 68, Issue 6, pp 645–661 | Cite as

Simulated wind-generated inertial oscillations compared to current measurements in the northern North Sea

  • Kjersti Bruserud
  • Sverre Haver
  • Dag Myrhaug


Measured current speed data show that episodes of wind-generated inertial oscillations dominate the current conditions in parts of the northern North Sea. In order to acquire current data of sufficient duration for robust estimation of joint metocean design conditions, such as wind, waves, and currents, a simple model for episodes of wind-generated inertial oscillations is adapted for the northern North Sea. The model is validated with and compared against measured current data at one location in the northern North Sea and found to reproduce the measured maximum current speed in each episode with considerable accuracy. The comparison is further improved when a small general background current is added to the simulated maximum current speeds. Extreme values of measured and simulated current speed are estimated and found to compare well. To assess the robustness of the model and the sensitivity of current conditions from location to location, the validated model is applied at three other locations in the northern North Sea. In general, the simulated maximum current speeds are smaller than the measured, suggesting that wind-generated inertial oscillations are not as prominent at these locations and that other current conditions may be governing. Further analysis of the simulated current speed and joint distribution of wind, waves, and currents for design of offshore structures will be presented in a separate paper.


Currents Wind-generated inertial oscillations Measurements Simulations Northern North Sea 



Empirical damping coefficient


Drag coefficient


current speed


Background current speed


Maximum current speed during an episode of wind-generated inertial oscillations


Current direction, degrees clockwise from north towards which the current is flowing


Mixed layer depth [m]


Wind stress force, x component


Coriolis parameter, 2Ωsinφ


Wind stress force, y component


Significant wave height


Norwegian Continental Shelf


Latitude, °N


Rotation of the Earth, 7.29 × 10−5 s−1


Air density


Water density


Annual probability of exceedance


Wind stress, vector


Wind stress, x component


Wind stress, y component


Wind direction, degrees clockwise from north towards which the wind is blowing


Wind-stress induced current, x component


Wind-stress induced current, y component


Wind velocity


Wind speed


Maximum wind speed during an episode of wind-generated inertial oscillations


Wind direction, degrees clockwise from north from which the wind is blowing



This work was made possible by funding from the Norwegian Research Council’s Industrial PhD-program (231832) and from Statoil. Sincere gratitude is expressed to chief engineer Simen Moxnes who secured Statoil’s funding.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Statoil ASAStavangerNorway
  2. 2.Department of Marine TechnologyNorwegian University of Science and Technology (NTNU)TrondheimNorway
  3. 3.Department of Mechanical and Structural Engineering and Materials ScienceUniversity of StavangerStavangerNorway

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