# Changeset 11681

Ignore:
Timestamp:
2019-10-11T00:15:54+02:00 (11 months ago)
Message:

Wednsday's changes

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 r11680 \end{listing} %-------------------------------------------------------------------------------------------------------------- \paragraph{Namelist choices} Most of the namelist options refer to how to specify the Stokes surface drift and penetration depth. There are three options: \begin{enumerate} \item \texttt{nn_osm_wave=0}. In this case the Stokes drift is assumed to be parallel to the surface wind stress, with magnitude consistent with a constant turbulent Langmuir number $\mathrm{La}_t= \texttt{rn_m_la}$ i.e.\ $u_[s0}=\tau/(\texttt{rn_m_la}^2\rho_0)$. \item \texttt{nn_osm_wave=1}. In this case the Stokes drift is assumed to be parallel to the surface wind stress, with magnitude as in the classical Pierson-Moskowitz wind-sea spectrum. \item \texttt{nn_osm_wave=2}. In this case the Stokes drift is taken from  ECMWF wave model output. Significant wave height and wave-mean period are used to calciulate the Stokes penetration depth, followingh the approach set out in Breivik(XXxx) \end{enumerate} \subsubsection{Summary} Much of the time the turbulent motions in the ocean surface boundary layer (OSBL) are not given by \nu_{\ast}= \left\{ u_*^3 \left[1-\exp(-1.5 \mathrm{La}_t^2})\right]+w_{*L}^3\right\}^{1/3}. \end{equation} For the unstable boundary layer this is merged with the standard convective velocity scale $w_{*C}=\left(\overline{w^\prime b^\prime}_0 \,h_\mathrm{ml}\right)^{1/3}$, where $\overline{w^\prime b^\prime}_0$ is the upwards surface buoyancy flux to give: For the unstable boundary layer this is merged with the standard convective velocity scale $w_{*C}=\left(\overline{w^\prime b^\prime}_0 \,h_\mathrm{ml}\right)^{1/3}$, where $\overline{w^\prime b^\prime}_0$ is the upwards surface buoyancy flux, to give: \begin{equation}\label{eq:vel-scale-unstable} \omega_* = \left(\nu_*^3 + 0.5 w_{*C}^3\right)^{1/3}.