GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • CD‐grid like finite elements  (1)
  • Wind-driven internal gravity waves  (1)
  • 2020-2024  (2)
Document type
Language
Years
  • 2020-2024  (2)
Year
  • 1
    Publication Date: 2023-06-21
    Description: Surface windstress transfers energy to the surface mixed layer of the ocean, and this energy partly radiates as internal gravity waves with near-inertial frequencies into the stratified ocean below the mixed layer where it is available for mixing. Numerical and analytical models provide estimates of the energy transfer into the mixed layer and the fraction radiated into the interior, but with large uncertainties, which we aim to reduce in the present study. An analytical slab model of the mixed layer used before in several studies is extended by consistent physics of wave radiation into the interior. Rayleigh damping, controlling the physics of the original slab model, is absent in the extended model and the wave-induced pressure gradient is resolved. The extended model predicts the energy transfer rates, both in physical and wavenumber-frequency space, associated with the wind forcing, dissipation in the mixed layer, and wave radiation at the base as function of a few parameters: mixed layer depth, Coriolis frequency and Brunt-Väisälä frequency below the mixed layer, and parameters of the applied windstress spectrum. The results of the model are satisfactorily validated with a realistic numerical model of the North Atlantic Ocean.
    Description: Deutsche Forschungsgemeinschaft https://doi.org/10.13039/501100001659
    Keywords: ddc:551.5 ; Wind-driven internal gravity waves ; Wave radiation physics
    Language: English
    Type: doc-type:article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2024-04-02
    Description: We present a new discretization of sea ice dynamics on the sphere. The approach describes sea ice motion in tangent planes to the sphere. On each triangle of the mesh, the ice dynamics are discretized in a local coordinate system using a CD‐grid‐like non‐conforming finite element method. The development allows a straightforward coupling to the C‐grid like ocean model in Icosahedral Non‐hydrostatic‐Ocean model, which uses the same infrastructure as the sea ice module. Using a series of test examples, we demonstrate that the non‐conforming finite element discretization provides a stable realization of large‐scale sea ice dynamics on the sphere. A comparison with observation shows that we can simulate typical drift patterns with the new numerical realization of the sea ice dynamics.
    Description: Plain Language Summary: Sea ice in polar regions plays an important role in the exchange of heat and freshwater between the atmosphere and the ocean and hence for climate in general. Therefore climate models require a description (a set of equations) to express the large‐scale sea ice motion. We present a mathematical framework for describing sea ice flow in a global three‐dimensional Cartesian system. The idea is to express the sea ice motion in tangent planes. In this reference system, we solve the mathematical equations that describe the sea ice motion. The equations are approximated on a computational grid, that consists of triangles covering the surface of the sphere. On each triangle the sea ice velocity is placed at the edge midpoint. The development is motivated by the infrastructure of the ocean and sea ice model Icosahedral Non‐hydrostatic‐Ocean model. The old representation of sea ice dynamics uses a different design principle. Therefore, the communication between the sea ice and ocean model is computationally expensive. To circumvent this problem we have developed a numerical realization of sea ice dynamics that uses the same infrastructure as the ocean model. We show that the new realization of the sea ice dynamics is capable of capturing the sea ice drift.
    Description: Key Points: First realization of sea ice dynamics in tangent planes to the sphere. Discretization of the sea ice dynamics in a three‐dimensional Cartesian framework. Realization of the sea ice dynamics in the ocean and sea ice model Icosahedral Non‐hydrostatic‐Ocean model.
    Description: Max Planck Society
    Description: DFG
    Description: Collaborative Research Center TRR 181
    Description: Scientific Steering Committee
    Description: http://dx.doi.org/10.17632/2v5shnnmwx
    Description: https://mpimet.mpg.de/en/science/modeling-with-icon/code-availability
    Description: https://thredds.met.no/thredds/osisaf/osisaf_cdrseaiceconc.html
    Description: http://dx.doi.org/10.22033/ESGF/input4MIPs.10842
    Description: http://dx.doi.org/10.5067/INAWUWO7QH7B
    Keywords: ddc:551.3 ; CD‐grid like finite elements ; sea ice dynamics ; ICON‐O
    Language: English
    Type: doc-type:article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...