In the default version of CICE, wave forcing can be read from an input file; however, wave propagation through sea ice is not included. As a result, attenuation of wave energy by sea ice is not represented, leading to unrealistic behaviour in the floe size distribution (FSD).
To enable very basic wave propagation, I propose implementing a simple wave propagation scheme using:
$$ S(f; x_{j}) = S(f; x_{i}) \exp (-\alpha (f) a_{\text{ice}} (x_j) d_{i,j}), \quad \quad (1)$$
where:
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$S(f; x_{i})$ is the spectral density function in terms of frequency at location $x_i$,
-
$a_{\text{ice}}(x_j)$ is the areal ice concentration at location $x_j$,
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$d_{i,j}$ is the distance between cells $x_i$ and $x_j$
- the attenuation coefficient $\alpha(f)$ is taken from Meylan, Bennetts, Kohout, GRL (2014).
First, we populate waves in the ice free domain (i.e., open ocean; $a_{\text{ice}} < 0.15$).
The propagation algorithm proceeds as follows:
- Select a cell in the model domain.
- If a cell $x_j$ has $ a_{\text{ice}} \geq 0.15$
- Search the neighbouring cells (using Rook contiguity)
- If any neighbour contains wave information, select the neighbour that is furthest away in terms of latitude. This step ensures that waves propagate towards each pole, exploiting the grid’s projection.
- Apply the propagation step using Eq.(1).
- Repeat these steps until a sufficient number of passes have been made.
In the default version of CICE, wave forcing can be read from an input file; however, wave propagation through sea ice is not included. As a result, attenuation of wave energy by sea ice is not represented, leading to unrealistic behaviour in the floe size distribution (FSD).
To enable very basic wave propagation, I propose implementing a simple wave propagation scheme using:
where:
First, we populate waves in the ice free domain (i.e., open ocean;$a_{\text{ice}} < 0.15$ ).
The propagation algorithm proceeds as follows: