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% $Name$ |
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\section{Example: Four layer Baroclinic Ocean Gyre In Spherical Coordinates} |
\section{Four Layer Baroclinic Ocean Gyre In Spherical Coordinates} |
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\label{sec:eg-fourlayer} |
\label{www:tutorials} |
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\label{sect:eg-fourlayer} |
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\bodytext{bgcolor="#FFFFFFFF"} |
\bodytext{bgcolor="#FFFFFFFF"} |
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This document describes an example experiment using MITgcm |
This document describes an example experiment using MITgcm |
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to simulate a baroclinic ocean gyre in spherical |
to simulate a baroclinic ocean gyre in spherical |
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polar coordinates. The barotropic |
polar coordinates. The barotropic |
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example experiment in section \ref{sec:eg-baro} |
example experiment in section \ref{sect:eg-baro} |
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ilustrated how to configure the code for a single layer |
illustrated how to configure the code for a single layer |
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simulation in a cartesian grid. In this example a similar physical problem |
simulation in a Cartesian grid. In this example a similar physical problem |
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is simulated, but the code is now configured |
is simulated, but the code is now configured |
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for four layers and in a spherical polar coordinate system. |
for four layers and in a spherical polar coordinate system. |
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\subsection{Overview} |
\subsection{Overview} |
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|
\label{www:tutorials} |
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This example experiment demonstrates using the MITgcm to simulate |
This example experiment demonstrates using the MITgcm to simulate |
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a baroclinic, wind-forced, ocean gyre circulation. The experiment |
a baroclinic, wind-forced, ocean gyre circulation. The experiment |
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is a numerical rendition of the gyre circulation problem simliar |
is a numerical rendition of the gyre circulation problem similar |
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to the problems described analytically by Stommel in 1966 |
to the problems described analytically by Stommel in 1966 |
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\cite{Stommel66} and numerically in Holland et. al \cite{Holland75}. |
\cite{Stommel66} and numerically in Holland et. al \cite{Holland75}. |
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\\ |
\\ |
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In this experiment the model is configured to represent a mid-latitude |
In this experiment the model is configured to represent a mid-latitude |
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enclosed sector of fluid on a sphere, $60^{\circ} \times 60^{\circ}$ in |
enclosed sector of fluid on a sphere, $60^{\circ} \times 60^{\circ}$ in |
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lateral extent. The fluid is $2$~km deep and is forced |
lateral extent. The fluid is $2$~km deep and is forced |
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by a constant in time zonal wind stress, $\tau_x$, that varies sinusoidally |
by a constant in time zonal wind stress, $\tau_{\lambda}$, that varies |
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in the north-south direction. Topologically the simulated |
sinusoidally in the north-south direction. Topologically the simulated |
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domain is a sector on a sphere and the coriolis parameter, $f$, is defined |
domain is a sector on a sphere and the coriolis parameter, $f$, is defined |
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according to latitude, $\varphi$ |
according to latitude, $\varphi$ |
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|
|
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\begin{equation} |
\begin{equation} |
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\label{EQ:fcori} |
\label{EQ:eg-fourlayer-fcori} |
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f(\varphi) = 2 \Omega \sin( \varphi ) |
f(\varphi) = 2 \Omega \sin( \varphi ) |
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\end{equation} |
\end{equation} |
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\begin{equation} |
\begin{equation} |
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\label{EQ:taux} |
\label{EQ:taux} |
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\tau_x(\varphi) = \tau_{0}\sin(\pi \frac{\varphi}{L_{\varphi}}) |
\tau_{\lambda}(\varphi) = \tau_{0}\sin(\pi \frac{\varphi}{L_{\varphi}}) |
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\end{equation} |
\end{equation} |
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|
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\noindent where $L_{\varphi}$ is the lateral domain extent ($60^{\circ}$) and |
\noindent where $L_{\varphi}$ is the lateral domain extent ($60^{\circ}$) and |
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$\tau_0$ is set to $0.1N m^{-2}$. |
$\tau_0$ is set to $0.1N m^{-2}$. |
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\\ |
\\ |
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Figure \ref{FIG:simulation_config} |
Figure \ref{FIG:eg-fourlayer-simulation_config} |
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summarises the configuration simulated. |
summarizes the configuration simulated. |
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In contrast to the example in section \ref{sec:eg-baro}, the |
In contrast to the example in section \ref{sect:eg-baro}, the |
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current experiment simulates a spherical polar domain. However, as indicated |
current experiment simulates a spherical polar domain. As indicated |
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by the axes in the lower left of the figure the model code works internally |
by the axes in the lower left of the figure the model code works internally |
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in a locally orthoganal coordinate $(x,y,z)$. For this experiment description |
in a locally orthogonal coordinate $(x,y,z)$. For this experiment description |
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of this document the local orthogonal model coordinate $(x,y,z)$ is synonomous |
the local orthogonal model coordinate $(x,y,z)$ is synonymous |
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with the spherical polar coordinate shown in figure |
with the coordinates $(\lambda,\varphi,r)$ shown in figure |
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\ref{fig:spherical-polar-coord} |
\ref{fig:spherical-polar-coord} |
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\\ |
\\ |
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linear |
linear |
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\begin{equation} |
\begin{equation} |
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\label{EQ:linear1_eos} |
\label{EQ:eg-fourlayer-linear1_eos} |
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\rho = \rho_{0} ( 1 - \alpha_{\theta}\theta^{'} ) |
\rho = \rho_{0} ( 1 - \alpha_{\theta}\theta^{'} ) |
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\end{equation} |
\end{equation} |
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\noindent which is implemented in the model as a density anomaly equation |
\noindent which is implemented in the model as a density anomaly equation |
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\begin{equation} |
\begin{equation} |
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\label{EQ:linear1_eos_pert} |
\label{EQ:eg-fourlayer-linear1_eos_pert} |
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\rho^{'} = -\rho_{0}\alpha_{\theta}\theta^{'} |
\rho^{'} = -\rho_{0}\alpha_{\theta}\theta^{'} |
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\end{equation} |
\end{equation} |
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\noindent with $\rho_{0}=999.8\,{\rm kg\,m}^{-3}$ and |
\noindent with $\rho_{0}=999.8\,{\rm kg\,m}^{-3}$ and |
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$\alpha_{\theta}=2\times10^{-4}\,{\rm degrees}^{-1} $. Integrated forward in |
$\alpha_{\theta}=2\times10^{-4}\,{\rm degrees}^{-1} $. Integrated forward in |
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this configuration the model state variable {\bf theta} is synonomous with |
this configuration the model state variable {\bf theta} is equivalent to |
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either in-situ temperature, $T$, or potential temperature, $\theta$. For |
either in-situ temperature, $T$, or potential temperature, $\theta$. For |
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consistency with later examples, in which the equation of state is |
consistency with later examples, in which the equation of state is |
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non-linear, we use $\theta$ to represent temperature here. This is |
non-linear, we use $\theta$ to represent temperature here. This is |
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\caption{Schematic of simulation domain and wind-stress forcing function |
\caption{Schematic of simulation domain and wind-stress forcing function |
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for the four-layer gyre numerical experiment. The domain is enclosed by solid |
for the four-layer gyre numerical experiment. The domain is enclosed by solid |
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walls at $0^{\circ}$~E, $60^{\circ}$~E, $0^{\circ}$~N and $60^{\circ}$~N. |
walls at $0^{\circ}$~E, $60^{\circ}$~E, $0^{\circ}$~N and $60^{\circ}$~N. |
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In the four-layer case an initial temperature stratification is |
An initial stratification is |
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imposed by setting the potential temperature, $\theta$, in each layer. |
imposed by setting the potential temperature, $\theta$, in each layer. |
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The vertical spacing, $\Delta z$, is constant and equal to $500$m. |
The vertical spacing, $\Delta z$, is constant and equal to $500$m. |
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} |
} |
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\label{FIG:simulation_config} |
\label{FIG:eg-fourlayer-simulation_config} |
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\end{figure} |
\end{figure} |
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\subsection{Equations solved} |
\subsection{Equations solved} |
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|
\label{www:tutorials} |
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The implicit free surface form of the |
For this problem |
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pressure equation described in Marshall et. al \cite{Marshall97a} is |
the implicit free surface, {\bf HPE} (see section \ref{sect:hydrostatic_and_quasi-hydrostatic_forms}) form of the |
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employed. |
equations described in Marshall et. al \cite{marshall:97a} are |
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A horizontal laplacian operator $\nabla_{h}^2$ provides viscous |
employed. The flow is three-dimensional with just temperature, $\theta$, as |
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dissipation. The wind-stress momentum input is added to the momentum equation |
an active tracer. The equation of state is linear. |
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for the ``zonal flow'', $u$. Other terms in the model |
A horizontal Laplacian operator $\nabla_{h}^2$ provides viscous |
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are explicitly switched off for this experiement configuration (see section |
dissipation and provides a diffusive sub-grid scale closure for the |
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\ref{SEC:code_config} ). This yields an active set of equations in |
temperature equation. A wind-stress momentum forcing is added to the momentum |
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equation for the zonal flow, $u$. Other terms in the model |
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are explicitly switched off for this experiment configuration (see section |
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\ref{SEC:eg_fourl_code_config} ). This yields an active set of equations |
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solved in this configuration, written in spherical polar coordinates as |
solved in this configuration, written in spherical polar coordinates as |
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follows |
follows |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:model_equations} |
\label{EQ:eg-fourlayer-model_equations} |
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\frac{Du}{Dt} - fv + |
\frac{Du}{Dt} - fv + |
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\frac{1}{\rho}\frac{\partial p^{\prime}}{\partial \lambda} - |
\frac{1}{\rho}\frac{\partial p^{\prime}}{\partial \lambda} - |
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A_{h}\nabla_{h}^2u - A_{z}\frac{\partial^{2}u}{\partial z^{2}} |
A_{h}\nabla_{h}^2u - A_{z}\frac{\partial^{2}u}{\partial z^{2}} |
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& = & |
& = & |
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\cal{F} |
\cal{F}_{\lambda} |
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\\ |
\\ |
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\frac{Dv}{Dt} + fu + |
\frac{Dv}{Dt} + fu + |
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\frac{1}{\rho}\frac{\partial p^{\prime}}{\partial \varphi} - |
\frac{1}{\rho}\frac{\partial p^{\prime}}{\partial \varphi} - |
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& = & |
& = & |
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0 |
0 |
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\\ |
\\ |
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\frac{\partial \eta}{\partial t} + \frac{\partial H \hat{u}}{\partial \lambda} + |
\frac{\partial \eta}{\partial t} + \frac{\partial H \widehat{u}}{\partial \lambda} + |
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\frac{\partial H \hat{v}}{\partial \varphi} |
\frac{\partial H \widehat{v}}{\partial \varphi} |
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&=& |
&=& |
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0 |
0 |
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|
\label{eq:fourl_example_continuity} |
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\\ |
\\ |
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\frac{D\theta}{Dt} - |
\frac{D\theta}{Dt} - |
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K_{h}\nabla_{h}^2\theta - K_{z}\frac{\partial^{2}\theta}{\partial z^{2}} |
K_{h}\nabla_{h}^2\theta - K_{z}\frac{\partial^{2}\theta}{\partial z^{2}} |
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& = & |
& = & |
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0 |
0 |
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|
\label{eq:eg_fourl_theta} |
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\\ |
\\ |
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p^{\prime} & = & |
p^{\prime} & = & |
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g\rho_{0} \eta + \int^{0}_{-z}\rho^{\prime} dz |
g\rho_{0} \eta + \int^{0}_{-z}\rho^{\prime} dz |
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\\ |
\\ |
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\rho^{\prime} & = &- \alpha_{\theta}\rho_{0}\theta^{\prime} |
\rho^{\prime} & = &- \alpha_{\theta}\rho_{0}\theta^{\prime} |
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\\ |
\\ |
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{\cal F} |_{s} & = & \frac{\tau_{x}}{\rho_{0}\Delta z_{s}} |
{\cal F}_{\lambda} |_{s} & = & \frac{\tau_{\lambda}}{\rho_{0}\Delta z_{s}} |
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\\ |
\\ |
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{\cal F} |_{i} & = & 0 |
{\cal F}_{\lambda} |_{i} & = & 0 |
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\end{eqnarray} |
\end{eqnarray} |
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\noindent where $u$ and $v$ are the components of the horizontal |
\noindent where $u$ and $v$ are the components of the horizontal |
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flow vector $\vec{u}$ on the sphere ($u=\dot{\lambda},v=\dot{\varphi}$). |
flow vector $\vec{u}$ on the sphere ($u=\dot{\lambda},v=\dot{\varphi}$). |
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The terms $H\hat{u}$ and $H\hat{v}$ are the components of the term |
The terms $H\widehat{u}$ and $H\widehat{v}$ are the components of the vertical |
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integrated in eqaution \ref{eq:free-surface}, as descirbed in section |
integral term given in equation \ref{eq:free-surface} and |
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explained in more detail in section \ref{sect:pressure-method-linear-backward}. |
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However, for the problem presented here, the continuity relation (equation |
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\ref{eq:fourl_example_continuity}) differs from the general form given |
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in section \ref{sect:pressure-method-linear-backward}, |
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equation \ref{eq:linear-free-surface=P-E+R}, because the source terms |
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${\cal P}-{\cal E}+{\cal R}$ |
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are all $0$. |
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The suffices ${s},{i}$ indicate surface and interior of the domain. |
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The forcing $\cal F$ is only applied at the surface. |
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The pressure field, $p^{\prime}$, is separated into a barotropic part |
The pressure field, $p^{\prime}$, is separated into a barotropic part |
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due to variations in sea-surface height, $\eta$, and a hydrostatic |
due to variations in sea-surface height, $\eta$, and a hydrostatic |
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part due to variations in density, $\rho^{\prime}$, over the water column. |
part due to variations in density, $\rho^{\prime}$, integrated |
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through the water column. |
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The suffices ${s},{i}$ indicate surface layer and the interior of the domain. |
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The windstress forcing, ${\cal F}_{\lambda}$, is applied in the surface layer |
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by a source term in the zonal momentum equation. In the ocean interior |
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this term is zero. |
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In the momentum equations |
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lateral and vertical boundary conditions for the $\nabla_{h}^{2}$ |
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and $\frac{\partial^{2}}{\partial z^{2}}$ operators are specified |
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when the numerical simulation is run - see section |
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\ref{SEC:eg_fourl_code_config}. For temperature |
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the boundary condition is ``zero-flux'' |
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e.g. $\frac{\partial \theta}{\partial \varphi}= |
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\frac{\partial \theta}{\partial \lambda}=\frac{\partial \theta}{\partial z}=0$. |
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\subsection{Discrete Numerical Configuration} |
\subsection{Discrete Numerical Configuration} |
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|
\label{www:tutorials} |
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The model is configured in hydrostatic form. The domain is discretised with |
The domain is discretised with |
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a uniform grid spacing in latitude and longitude |
a uniform grid spacing in latitude and longitude |
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$\Delta \lambda=\Delta \varphi=1^{\circ}$, so |
$\Delta \lambda=\Delta \varphi=1^{\circ}$, so |
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that there are sixty grid cells in the zonal and meridional directions. |
that there are sixty grid cells in the zonal and meridional directions. |
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Vertically the |
Vertically the |
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model is configured with four layers with constant depth, |
model is configured with four layers with constant depth, |
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$\Delta z$, of $500$~m. The internal, locally orthogonal, model coordinate |
$\Delta z$, of $500$~m. The internal, locally orthogonal, model coordinate |
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variables $x$ and $y$ are initialised from the values of |
variables $x$ and $y$ are initialized from the values of |
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$\lambda$, $\varphi$, $\Delta \lambda$ and $\Delta \varphi$ in |
$\lambda$, $\varphi$, $\Delta \lambda$ and $\Delta \varphi$ in |
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radians according to |
radians according to |
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The procedure for generating a set of internal grid variables from a |
The procedure for generating a set of internal grid variables from a |
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spherical polar grid specification is discussed in section |
spherical polar grid specification is discussed in section |
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\ref{sec:spatial_discrete_horizontal_grid}. |
\ref{sect:spatial_discrete_horizontal_grid}. |
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\noindent\fbox{ \begin{minipage}{5.5in} |
\noindent\fbox{ \begin{minipage}{5.5in} |
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{\em S/R INI\_SPHERICAL\_POLAR\_GRID} ({\em |
{\em S/R INI\_SPHERICAL\_POLAR\_GRID} ({\em |
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As described in \ref{sec:tracer_equations}, the time evolution of potential |
As described in \ref{sect:tracer_equations}, the time evolution of potential |
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temperature, |
temperature, |
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$\theta$, equation is solved prognostically. |
$\theta$, (equation \ref{eq:eg_fourl_theta}) |
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is evaluated prognostically. The centered second-order scheme with |
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Adams-Bashforth time stepping described in section |
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\ref{sect:tracer_equations_abII} is used to step forward the temperature |
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equation. Prognostic terms in |
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the momentum equations are solved using flux form as |
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described in section \ref{sect:flux-form_momentum_eqautions}. |
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The pressure forces that drive the fluid motions, ( |
The pressure forces that drive the fluid motions, ( |
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$\frac{\partial p^{'}}{\partial \lambda}$ and $\frac{\partial p^{'}}{\partial \varphi}$), are found by summing pressure due to surface |
$\frac{\partial p^{'}}{\partial \lambda}$ and $\frac{\partial p^{'}}{\partial \varphi}$), are found by summing pressure due to surface |
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elevation $\eta$ and the hydrostatic pressure. |
elevation $\eta$ and the hydrostatic pressure. The hydrostatic part of the |
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pressure is diagnosed explicitly by integrating density. The sea-surface |
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height, $\eta$, is diagnosed using an implicit scheme. The pressure |
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field solution method is described in sections |
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\ref{sect:pressure-method-linear-backward} and |
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\ref{sect:finding_the_pressure_field}. |
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\subsubsection{Numerical Stability Criteria} |
\subsubsection{Numerical Stability Criteria} |
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|
\label{www:tutorials} |
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The laplacian dissipation coefficient, $A_{h}$, is set to $400 m s^{-1}$. |
The Laplacian viscosity coefficient, $A_{h}$, is set to $400 m s^{-1}$. |
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This value is chosen to yield a Munk layer width \cite{Adcroft_thesis}, |
This value is chosen to yield a Munk layer width, |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:munk_layer} |
\label{EQ:eg-fourlayer-munk_layer} |
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M_{w} = \pi ( \frac { A_{h} }{ \beta } )^{\frac{1}{3}} |
M_{w} = \pi ( \frac { A_{h} }{ \beta } )^{\frac{1}{3}} |
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\end{eqnarray} |
\end{eqnarray} |
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\noindent of $\approx 100$km. This is greater than the model |
\noindent of $\approx 100$km. This is greater than the model |
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resolution in mid-latitudes $\Delta x$, ensuring that the frictional |
resolution in mid-latitudes |
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$\Delta x=r \cos(\varphi) \Delta \lambda \approx 80~{\rm km}$ at |
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$\varphi=45^{\circ}$, ensuring that the frictional |
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boundary layer is well resolved. |
boundary layer is well resolved. |
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\\ |
\\ |
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\noindent The model is stepped forward with a |
\noindent The model is stepped forward with a |
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time step $\delta t=1200$secs. With this time step the stability |
time step $\delta t=1200$secs. With this time step the stability |
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parameter to the horizontal laplacian friction \cite{Adcroft_thesis} |
parameter to the horizontal Laplacian friction |
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|
|
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:laplacian_stability} |
\label{EQ:eg-fourlayer-laplacian_stability} |
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S_{l} = 4 \frac{A_{h} \delta t}{{\Delta x}^2} |
S_{l} = 4 \frac{A_{h} \delta t}{{\Delta x}^2} |
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\end{eqnarray} |
\end{eqnarray} |
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\noindent evaluates to 0.012, which is well below the 0.3 upper limit |
\noindent evaluates to 0.012, which is well below the 0.3 upper limit |
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for stability. |
for stability for this term under ABII time-stepping. |
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\\ |
\\ |
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\noindent The vertical dissipation coefficient, $A_{z}$, is set to |
\noindent The vertical dissipation coefficient, $A_{z}$, is set to |
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$1\times10^{-2} {\rm m}^2{\rm s}^{-1}$. The associated stability limit |
$1\times10^{-2} {\rm m}^2{\rm s}^{-1}$. The associated stability limit |
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|
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:laplacian_stability_z} |
\label{EQ:eg-fourlayer-laplacian_stability_z} |
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S_{l} = 4 \frac{A_{z} \delta t}{{\Delta z}^2} |
S_{l} = 4 \frac{A_{z} \delta t}{{\Delta z}^2} |
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\end{eqnarray} |
\end{eqnarray} |
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\\ |
\\ |
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\noindent The numerical stability for inertial oscillations |
\noindent The numerical stability for inertial oscillations |
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\cite{Adcroft_thesis} |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:inertial_stability} |
\label{EQ:eg-fourlayer-inertial_stability} |
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S_{i} = f^{2} {\delta t}^2 |
S_{i} = f^{2} {\delta t}^2 |
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\end{eqnarray} |
\end{eqnarray} |
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limit for stability. |
limit for stability. |
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\\ |
\\ |
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\noindent The advective CFL \cite{Adcroft_thesis} for a extreme maximum |
\noindent The advective CFL for a extreme maximum |
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horizontal flow |
horizontal flow |
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speed of $ | \vec{u} | = 2 ms^{-1}$ |
speed of $ | \vec{u} | = 2 ms^{-1}$ |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:cfl_stability} |
\label{EQ:eg-fourlayer-cfl_stability} |
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S_{a} = \frac{| \vec{u} | \delta t}{ \Delta x} |
C_{a} = \frac{| \vec{u} | \delta t}{ \Delta x} |
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\end{eqnarray} |
\end{eqnarray} |
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\noindent evaluates to $5 \times 10^{-2}$. This is well below the stability |
\noindent evaluates to $5 \times 10^{-2}$. This is well below the stability |
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limit of 0.5. |
limit of 0.5. |
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\\ |
\\ |
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\noindent The stability parameter for internal gravity waves |
\noindent The stability parameter for internal gravity waves |
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\cite{Adcroft_thesis} |
propagating at $2~{\rm m}~{\rm s}^{-1}$ |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:igw_stability} |
\label{EQ:eg-fourlayer-igw_stability} |
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S_{c} = \frac{c_{g} \delta t}{ \Delta x} |
S_{c} = \frac{c_{g} \delta t}{ \Delta x} |
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\end{eqnarray} |
\end{eqnarray} |
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|
344 |
\noindent evaluates to $5 \times 10^{-2}$. This is well below the linear |
\noindent evaluates to $\approx 5 \times 10^{-2}$. This is well below the linear |
345 |
stability limit of 0.25. |
stability limit of 0.25. |
346 |
|
|
347 |
\subsection{Code Configuration} |
\subsection{Code Configuration} |
348 |
\label{SEC:code_config} |
\label{www:tutorials} |
349 |
|
\label{SEC:eg_fourl_code_config} |
350 |
|
|
351 |
The model configuration for this experiment resides under the |
The model configuration for this experiment resides under the |
352 |
directory {\it verification/exp1/}. The experiment files |
directory {\it verification/exp2/}. The experiment files |
353 |
\begin{itemize} |
\begin{itemize} |
354 |
\item {\it input/data} |
\item {\it input/data} |
355 |
\item {\it input/data.pkg} |
\item {\it input/data.pkg} |
360 |
\item {\it code/CPP\_OPTIONS.h}, |
\item {\it code/CPP\_OPTIONS.h}, |
361 |
\item {\it code/SIZE.h}. |
\item {\it code/SIZE.h}. |
362 |
\end{itemize} |
\end{itemize} |
363 |
contain the code customisations and parameter settings for this |
contain the code customisations and parameter settings for this |
364 |
experiements. Below we describe the customisations |
experiment. Below we describe the customisations to these files |
365 |
to these files associated with this experiment. |
associated with this experiment. |
366 |
|
|
367 |
\subsubsection{File {\it input/data}} |
\subsubsection{File {\it input/data}} |
368 |
|
\label{www:tutorials} |
369 |
|
|
370 |
This file, reproduced completely below, specifies the main parameters |
This file, reproduced completely below, specifies the main parameters |
371 |
for the experiment. The parameters that are significant for this configuration |
for the experiment. The parameters that are significant for this configuration |
375 |
|
|
376 |
\item Line 4, |
\item Line 4, |
377 |
\begin{verbatim} tRef=20.,10.,8.,6., \end{verbatim} |
\begin{verbatim} tRef=20.,10.,8.,6., \end{verbatim} |
378 |
this line sets |
this line sets the initial and reference values of potential |
379 |
the initial and reference values of potential temperature at each model |
temperature at each model level in units of $^{\circ}$C. The entries |
380 |
level in units of $^{\circ}$C. |
are ordered from surface to depth. For each depth level the initial |
381 |
The entries are ordered from surface to depth. For each |
and reference profiles will be uniform in $x$ and $y$. The values |
382 |
depth level the inital and reference profiles will be uniform in |
specified here are read into the variable \varlink{tRef}{tRef} in the |
383 |
$x$ and $y$. The values specified here are read into the |
model code, by procedure \filelink{INI\_PARMS}{model-src-ini_parms.F} |
|
variable |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/names/OK.htm> \end{rawhtml} |
|
|
tRef |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
in the model code, by procedure |
|
|
{\it |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
|
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
%% \codelink{var:tref} tRef \endlink |
|
|
%% \codelink{file:ini_parms} {\it INI\_PARMS } \endlink |
|
|
%% \codelink{proc:ini_parms} {\it INI\_PARMS } \endlink |
|
|
%% \var{tref} |
|
|
%% \proc{ini_parms} |
|
|
%% \file{ini_parms} |
|
|
\newcommand{\VARtref}{ |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/names/OK.htm> \end{rawhtml} |
|
|
tRef |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
} |
|
|
|
|
|
|
|
384 |
|
|
385 |
\fbox{ |
\fbox{ |
386 |
\begin{minipage}{5.0in} |
\begin{minipage}{5.0in} |
387 |
{\it S/R INI\_THETA} |
{\it S/R INI\_THETA}({\it ini\_theta.F}) |
388 |
({\it ini\_theta.F}) |
\end{minipage} |
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/98.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
389 |
} |
} |
390 |
|
\filelink{ini\_theta.F}{model-src-ini_theta.F} |
391 |
|
|
392 |
\item Line 6, |
\item Line 6, |
393 |
\begin{verbatim} viscAz=1.E-2, \end{verbatim} |
\begin{verbatim} viscAz=1.E-2, \end{verbatim} |
394 |
this line sets the vertical laplacian dissipation coefficient to |
this line sets the vertical Laplacian dissipation coefficient to $1 |
395 |
$1 \times 10^{-2} {\rm m^{2}s^{-1}}$. Boundary conditions |
\times 10^{-2} {\rm m^{2}s^{-1}}$. Boundary conditions for this |
396 |
for this operator are specified later. |
operator are specified later. The variable \varlink{viscAz}{viscAz} |
397 |
The variable |
is read in the routine \filelink{ini\_parms.F}{model-src-ini_parms.F} |
398 |
{\bf |
and is copied into model general vertical coordinate variable |
399 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/ZQ.htm> \end{rawhtml} |
\varlink{viscAr}{viscAr} At each time step, the viscous term |
400 |
viscAz |
contribution to the momentum equations is calculated in routine |
401 |
\begin{rawhtml} </A>\end{rawhtml} |
\varlink{CALC\_DIFFUSIVITY}{CALC_DIFFUSIVITY} |
|
} |
|
|
is read in the routine |
|
|
{\it |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
|
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
and is copied into model general vertical coordinate variable |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/names/PF.htm> \end{rawhtml} |
|
|
viscAr |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
402 |
|
|
403 |
\fbox{ |
\fbox{ |
404 |
\begin{minipage}{5.0in} |
\begin{minipage}{5.0in} |
405 |
{\it S/R CALC\_DIFFUSIVITY}({\it calc\_diffusivity.F}) |
{\it S/R CALC\_DIFFUSIVITY}({\it calc\_diffusivity.F}) |
406 |
\end{minipage} |
\end{minipage} |
407 |
} |
} |
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/53.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
408 |
|
|
409 |
\item Line 7, |
\item Line 7, |
410 |
\begin{verbatim} |
\begin{verbatim} |
411 |
viscAh=4.E2, |
viscAh=4.E2, |
412 |
\end{verbatim} |
\end{verbatim} |
413 |
this line sets the horizontal laplacian frictional dissipation coefficient to |
this line sets the horizontal laplacian frictional dissipation |
414 |
$1 \times 10^{-2} {\rm m^{2}s^{-1}}$. Boundary conditions |
coefficient to $1 \times 10^{-2} {\rm m^{2}s^{-1}}$. Boundary |
415 |
for this operator are specified later. |
conditions for this operator are specified later. The variable |
416 |
The variable |
\varlink{viscAh}{viscAh} is read in the routine |
417 |
{\bf |
\varlink{INI\_PARMS}{INI_PARMS} and applied in routines |
418 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/SI.htm> \end{rawhtml} |
\varlink{CALC\_MOM\_RHS}{CALC_MOM_RHS} and |
419 |
viscAh |
\varlink{CALC\_GW}{CALC_GW}. |
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
is read in the routine |
|
|
{\it |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
|
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
420 |
|
|
421 |
\fbox{ |
\fbox{ |
422 |
\begin{minipage}{5.0in} |
\begin{minipage}{5.0in} |
423 |
{\it S/R CALC\_MOM\_RHS}({\it calc\_mom\_rhs.F}) |
{\it S/R CALC\_MOM\_RHS}({\it calc\_mom\_rhs.F}) |
424 |
\end{minipage} |
\end{minipage} |
425 |
} |
} |
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/60.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
|
|
426 |
\fbox{ |
\fbox{ |
427 |
\begin{minipage}{5.0in} |
\begin{minipage}{5.0in} |
428 |
{\it S/R CALC\_GW}({\it calc\_gw.F}) |
{\it S/R CALC\_GW}({\it calc\_gw.F}) |
429 |
\end{minipage} |
\end{minipage} |
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/58.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
430 |
} |
} |
431 |
|
|
432 |
\item Lines 8, |
\item Line 8, |
433 |
\begin{verbatim} |
\begin{verbatim} |
434 |
no_slip_sides=.FALSE. |
no_slip_sides=.FALSE. |
435 |
\end{verbatim} |
\end{verbatim} |
436 |
this line selects a free-slip lateral boundary condition for |
this line selects a free-slip lateral boundary condition for the |
437 |
the horizontal laplacian friction operator |
horizontal laplacian friction operator e.g. $\frac{\partial |
438 |
e.g. $\frac{\partial u}{\partial y}$=0 along boundaries in $y$ and |
u}{\partial y}$=0 along boundaries in $y$ and $\frac{\partial |
439 |
$\frac{\partial v}{\partial x}$=0 along boundaries in $x$. |
v}{\partial x}$=0 along boundaries in $x$. The variable |
440 |
The variable |
\varlink{no\_slip\_sides}{no_slip_sides} is read in the routine |
441 |
{\bf |
\varlink{INI\_PARMS}{INI_PARMS} and the boundary condition is |
442 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/UT.htm> \end{rawhtml} |
evaluated in routine |
443 |
no\_slip\_sides |
|
444 |
\begin{rawhtml} </A>\end{rawhtml} |
\fbox{ |
445 |
} |
\begin{minipage}{5.0in} |
446 |
is read in the routine |
{\it S/R CALC\_MOM\_RHS}({\it calc\_mom\_rhs.F}) |
447 |
{\it |
\end{minipage} |
448 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
} |
449 |
INI\_PARMS |
\filelink{calc\_mom\_rhs.F}{calc_mom_rhs.F} |
450 |
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R CALC\_MOM\_RHS}({\it calc\_mom\_rhs.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/60.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
|
|
451 |
\item Lines 9, |
\item Lines 9, |
452 |
\begin{verbatim} |
\begin{verbatim} |
453 |
no_slip_bottom=.TRUE. |
no_slip_bottom=.TRUE. |
454 |
\end{verbatim} |
\end{verbatim} |
455 |
this line selects a no-slip boundary condition for bottom |
this line selects a no-slip boundary condition for bottom boundary |
456 |
boundary condition in the vertical laplacian friction operator |
condition in the vertical laplacian friction operator e.g. $u=v=0$ |
457 |
e.g. $u=v=0$ at $z=-H$, where $H$ is the local depth of the domain. |
at $z=-H$, where $H$ is the local depth of the domain. The variable |
458 |
The variable |
\varlink{no\_slip\_bottom}{no\_slip\_bottom} is read in the routine |
459 |
{\bf |
\filelink{INI\_PARMS}{model-src-ini_parms.F} and is applied in the |
460 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/UK.htm> \end{rawhtml} |
routine \varlink{CALC\_MOM\_RHS}{CALC_MOM_RHS}. |
461 |
no\_slip\_bottom |
|
462 |
\begin{rawhtml} </A>\end{rawhtml} |
\fbox{ |
463 |
} |
\begin{minipage}{5.0in} |
464 |
is read in the routine |
{\it S/R CALC\_MOM\_RHS}({\it calc\_mom\_rhs.F}) |
465 |
{\it |
\end{minipage} |
466 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
} |
467 |
INI\_PARMS |
\filelink{calc\_mom\_rhs.F}{calc_mom_rhs.F} |
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R CALC\_MOM\_RHS}({\it calc\_mom\_rhs.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/60.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
468 |
|
|
469 |
\item Line 10, |
\item Line 10, |
470 |
\begin{verbatim} |
\begin{verbatim} |
471 |
diffKhT=4.E2, |
diffKhT=4.E2, |
472 |
\end{verbatim} |
\end{verbatim} |
473 |
this line sets the horizontal diffusion coefficient for temperature |
this line sets the horizontal diffusion coefficient for temperature |
474 |
to $400\,{\rm m^{2}s^{-1}}$. The boundary condition on this |
to $400\,{\rm m^{2}s^{-1}}$. The boundary condition on this operator |
475 |
operator is $\frac{\partial}{\partial x}=\frac{\partial}{\partial y}=0$ at |
is $\frac{\partial}{\partial x}=\frac{\partial}{\partial y}=0$ at |
476 |
all boundaries. |
all boundaries. The variable \varlink{diffKhT}{diffKhT} is read in |
477 |
The variable |
the routine \varlink{INI\_PARMS}{INI_PARMS} and used in routine |
478 |
{\bf |
\varlink{CALC\_GT}{CALC_GT}. |
479 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/RC.htm> \end{rawhtml} |
|
480 |
diffKhT |
\fbox{ \begin{minipage}{5.0in} |
481 |
\begin{rawhtml} </A>\end{rawhtml} |
{\it S/R CALC\_GT}({\it calc\_gt.F}) |
482 |
} |
\end{minipage} |
483 |
is read in the routine |
} |
484 |
{\it |
\filelink{calc\_gt.F}{model-src-calc_gt.F} |
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
|
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ \begin{minipage}{5.0in} |
|
|
{\it S/R CALC\_GT}({\it calc\_gt.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/57.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
485 |
|
|
486 |
\item Line 11, |
\item Line 11, |
487 |
\begin{verbatim} |
\begin{verbatim} |
488 |
diffKzT=1.E-2, |
diffKzT=1.E-2, |
489 |
\end{verbatim} |
\end{verbatim} |
490 |
this line sets the vertical diffusion coefficient for temperature |
this line sets the vertical diffusion coefficient for temperature to |
491 |
to $10^{-2}\,{\rm m^{2}s^{-1}}$. The boundary condition on this |
$10^{-2}\,{\rm m^{2}s^{-1}}$. The boundary condition on this |
492 |
operator is $\frac{\partial}{\partial z}$ = 0 on all boundaries. |
operator is $\frac{\partial}{\partial z}$ = 0 on all boundaries. |
493 |
The variable |
The variable \varlink{diffKzT}{diffKzT} is read in the routine |
494 |
{\bf |
\varlink{INI\_PARMS}{INI_PARMS}. It is copied into model general |
495 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/ZT.htm> \end{rawhtml} |
vertical coordinate variable \varlink{diffKrT}{diffKrT} which is |
496 |
diffKzT |
used in routine \varlink{CALC\_DIFFUSIVITY}{CALC_DIFFUSIVITY}. |
497 |
\begin{rawhtml} </A>\end{rawhtml} |
|
498 |
} |
\fbox{ \begin{minipage}{5.0in} |
499 |
is read in the routine |
{\it S/R CALC\_DIFFUSIVITY}({\it calc\_diffusivity.F}) |
500 |
{\it |
\end{minipage} |
501 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
} |
502 |
INI\_PARMS |
\filelink{calc\_diffusivity.F}{model-src-calc_diffusivity.F} |
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
It is copied into model general vertical coordinate variable |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/names/PD.htm> \end{rawhtml} |
|
|
diffKrT |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ \begin{minipage}{5.0in} |
|
|
{\it S/R CALC\_DIFFUSIVITY}({\it calc\_diffusivity.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/53.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
|
|
|
|
|
503 |
|
|
504 |
\item Line 13, |
\item Line 13, |
505 |
\begin{verbatim} |
\begin{verbatim} |
506 |
tAlpha=2.E-4, |
tAlpha=2.E-4, |
507 |
\end{verbatim} |
\end{verbatim} |
508 |
This line sets the thermal expansion coefficient for the fluid |
This line sets the thermal expansion coefficient for the fluid to $2 |
509 |
to $2 \times 10^{-4}\,{\rm degrees}^{-1}$ |
\times 10^{-4}\,{\rm degrees}^{-1}$ The variable |
510 |
The variable |
\varlink{tAlpha}{tAlpha} is read in the routine |
511 |
{\bf |
\varlink{INI\_PARMS}{INI_PARMS}. The routine |
512 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/ZV.htm> \end{rawhtml} |
\varlink{FIND\_RHO}{FIND\_RHO} makes use of {\bf tAlpha}. |
513 |
tAlpha |
|
514 |
\begin{rawhtml} </A>\end{rawhtml} |
\fbox{ |
515 |
} |
\begin{minipage}{5.0in} |
516 |
is read in the routine |
{\it S/R FIND\_RHO}({\it find\_rho.F}) |
517 |
{\it |
\end{minipage} |
518 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
} |
519 |
INI\_PARMS |
\filelink{find\_rho.F}{model-src-find_rho.F} |
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R FIND\_RHO}({\it find\_rho.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/79.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
520 |
|
|
521 |
\item Line 18, |
\item Line 18, |
522 |
\begin{verbatim} |
\begin{verbatim} |
523 |
eosType='LINEAR' |
eosType='LINEAR' |
524 |
\end{verbatim} |
\end{verbatim} |
525 |
This line selects the linear form of the equation of state. |
This line selects the linear form of the equation of state. The |
526 |
The variable |
variable \varlink{eosType}{eosType} is read in the routine |
527 |
{\bf |
\varlink{INI\_PARMS}{INI_PARMS}. The values of {\bf eosType} sets |
528 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/WV.htm> \end{rawhtml} |
which formula in routine {\it FIND\_RHO} is used to calculate |
529 |
eosType |
density. |
530 |
\begin{rawhtml} </A>\end{rawhtml} |
|
531 |
} |
\fbox{ |
532 |
is read in the routine |
\begin{minipage}{5.0in} |
533 |
{\it |
{\it S/R FIND\_RHO}({\it find\_rho.F}) |
534 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
\end{minipage} |
535 |
INI\_PARMS |
} |
536 |
\begin{rawhtml} </A>\end{rawhtml} |
\filelink{find\_rho.F}{model-src-find_rho.F} |
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R FIND\_RHO}({\it find\_rho.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/79.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
|
|
|
|
|
537 |
|
|
538 |
\item Line 40, |
\item Line 40, |
539 |
\begin{verbatim} |
\begin{verbatim} |
540 |
usingSphericalPolarGrid=.TRUE., |
usingSphericalPolarGrid=.TRUE., |
541 |
\end{verbatim} |
\end{verbatim} |
542 |
This line requests that the simulation be performed in a |
This line requests that the simulation be performed in a spherical |
543 |
spherical polar coordinate system. It affects the interpretation of |
polar coordinate system. It affects the interpretation of grid input |
544 |
grid inoput parameters, for exampl {\bf delX} and {\bf delY} and |
parameters, for example {\bf delX} and {\bf delY} and causes the |
545 |
causes the grid generation routines to initialise an internal grid based |
grid generation routines to initialize an internal grid based on |
546 |
on spherical polar geometry. |
spherical polar geometry. The variable |
547 |
The variable |
\varlink{usingSphericalPolarGrid}{usingSphericalPolarGrid} is read |
548 |
{\bf |
in the routine \varlink{INI\_PARMS}{INI_PARMS}. When set to {\bf |
549 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/10T.htm> \end{rawhtml} |
.TRUE.} the settings of {\bf delX} and {\bf delY} are taken to be |
550 |
usingSphericalPolarGrid |
in degrees. These values are used in the routine |
551 |
\begin{rawhtml} </A>\end{rawhtml} |
|
552 |
} |
\fbox{ |
553 |
is read in the routine |
\begin{minipage}{5.0in} |
554 |
{\it |
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
555 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
\end{minipage} |
556 |
INI\_PARMS |
} |
557 |
\begin{rawhtml} </A>\end{rawhtml} |
\filelink{ini\_spherical\_polar\_grid.F}{model-src-ini_spherical_polar_grid.F} |
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/97.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
558 |
|
|
559 |
\item Line 41, |
\item Line 41, |
560 |
\begin{verbatim} |
\begin{verbatim} |
561 |
phiMin=0., |
phiMin=0., |
562 |
\end{verbatim} |
\end{verbatim} |
563 |
This line sets the southern boundary of the modeled |
This line sets the southern boundary of the modeled domain to |
564 |
domain to $0^{\circ}$ latitude. This value affects both the |
$0^{\circ}$ latitude. This value affects both the generation of the |
565 |
generation of the locally orthogonal grid that the model |
locally orthogonal grid that the model uses internally and affects |
566 |
uses internally and affects the initialisation of the coriolis force. |
the initialization of the coriolis force. Note - it is not required |
567 |
Note - it is not required to set |
to set a longitude boundary, since the absolute longitude does not |
568 |
a longitude boundary, since the absolute longitude does |
alter the kernel equation discretisation. The variable |
569 |
not alter the kernel equation discretisation. |
\varlink{phiMin}{phiMin} is read in the |
570 |
The variable |
routine \varlink{INI\_PARMS}{INI_PARMS} and is used in routine |
571 |
{\bf |
|
572 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/110.htm> \end{rawhtml} |
\fbox{ |
573 |
phiMin |
\begin{minipage}{5.0in} |
574 |
\begin{rawhtml} </A>\end{rawhtml} |
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
575 |
} |
\end{minipage} |
576 |
is read in the routine |
} |
577 |
{\it |
\filelink{ini\_spherical\_polar\_grid.F}{model-src-ini_spherical_polar_grid.F} |
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
|
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/97.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
578 |
|
|
579 |
\item Line 42, |
\item Line 42, |
580 |
\begin{verbatim} |
\begin{verbatim} |
581 |
delX=60*1., |
delX=60*1., |
582 |
\end{verbatim} |
\end{verbatim} |
583 |
This line sets the horizontal grid spacing between each y-coordinate line |
This line sets the horizontal grid spacing between each y-coordinate |
584 |
in the discrete grid to $1^{\circ}$ in longitude. |
line in the discrete grid to $1^{\circ}$ in longitude. The variable |
585 |
The variable |
\varlink{delX}{delX} is read in the routine |
586 |
{\bf |
\varlink{INI\_PARMS}{INI_PARMS} and is used in routine |
587 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/10Z.htm> \end{rawhtml} |
|
588 |
delX |
\fbox{ |
589 |
\begin{rawhtml} </A>\end{rawhtml} |
\begin{minipage}{5.0in} |
590 |
} |
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
591 |
is read in the routine |
\end{minipage} |
592 |
{\it |
} |
593 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
\filelink{ini\_spherical\_polar\_grid.F}{model-src-ini_spherical_polar_grid.F} |
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/97.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
594 |
|
|
595 |
\item Line 43, |
\item Line 43, |
596 |
\begin{verbatim} |
\begin{verbatim} |
597 |
delY=60*1., |
delY=60*1., |
598 |
\end{verbatim} |
\end{verbatim} |
599 |
This line sets the horizontal grid spacing between each y-coordinate line |
This line sets the horizontal grid spacing between each y-coordinate |
600 |
in the discrete grid to $1^{\circ}$ in latitude. |
line in the discrete grid to $1^{\circ}$ in latitude. The variable |
601 |
The variable |
\varlink{delY}{delY} is read in the routine |
602 |
{\bf |
\varlink{INI\_PARMS}{INI_PARMS} and is used in routine |
603 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/UB.htm> \end{rawhtml} |
|
604 |
delY |
\fbox{ |
605 |
\begin{rawhtml} </A>\end{rawhtml} |
\begin{minipage}{5.0in} |
606 |
} |
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
607 |
is read in the routine |
\end{minipage} |
608 |
{\it |
} |
609 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
\filelink{ini\_spherical\_polar\_grid.F}{model-src-ini_spherical_polar_grid.F} |
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_SPEHRICAL\_POLAR\_GRID}({\it ini\_spherical\_polar\_grid.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/97.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
610 |
|
|
611 |
\item Line 44, |
\item Line 44, |
612 |
\begin{verbatim} |
\begin{verbatim} |
613 |
delZ=500.,500.,500.,500., |
delZ=500.,500.,500.,500., |
614 |
\end{verbatim} |
\end{verbatim} |
615 |
This line sets the vertical grid spacing between each z-coordinate line |
This line sets the vertical grid spacing between each z-coordinate |
616 |
in the discrete grid to $500\,{\rm m}$, so that the total model depth |
line in the discrete grid to $500\,{\rm m}$, so that the total model |
617 |
is $2\,{\rm km}$. |
depth is $2\,{\rm km}$. The variable \varlink{delZ}{delZ} is read |
618 |
The variable |
in the routine \varlink{INI\_PARMS}{INI_PARMS}. It is copied into |
619 |
{\bf |
the internal model coordinate variable \varlink{delR}{delR} which is |
620 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/10W.htm> \end{rawhtml} |
used in routine |
621 |
delZ |
|
622 |
\begin{rawhtml} </A>\end{rawhtml} |
\fbox{ |
623 |
} |
\begin{minipage}{5.0in} |
624 |
is read in the routine |
{\it S/R INI\_VERTICAL\_GRID}({\it ini\_vertical\_grid.F}) |
625 |
{\it |
\end{minipage} |
626 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
} |
627 |
INI\_PARMS |
\filelink{ini\_vertical\_grid.F}{model-src-ini_vertical_grid.F} |
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
It is copied into the internal |
|
|
model coordinate variable |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/names/10Y.htm> \end{rawhtml} |
|
|
delR |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_VERTICAL\_GRID}({\it ini\_vertical\_grid.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/100.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
628 |
|
|
629 |
\item Line 47, |
\item Line 47, |
630 |
\begin{verbatim} |
\begin{verbatim} |
631 |
bathyFile='topog.box' |
bathyFile='topog.box' |
632 |
\end{verbatim} |
\end{verbatim} |
633 |
This line specifies the name of the file from which the domain |
This line specifies the name of the file from which the domain |
634 |
bathymetry is read. This file is a two-dimensional ($x,y$) map of |
bathymetry is read. This file is a two-dimensional ($x,y$) map of |
635 |
depths. This file is assumed to contain 64-bit binary numbers |
depths. This file is assumed to contain 64-bit binary numbers giving |
636 |
giving the depth of the model at each grid cell, ordered with the x |
the depth of the model at each grid cell, ordered with the x |
637 |
coordinate varying fastest. The points are ordered from low coordinate |
coordinate varying fastest. The points are ordered from low |
638 |
to high coordinate for both axes. The units and orientation of the |
coordinate to high coordinate for both axes. The units and |
639 |
depths in this file are the same as used in the MITgcm code. In this |
orientation of the depths in this file are the same as used in the |
640 |
experiment, a depth of $0m$ indicates a solid wall and a depth |
MITgcm code. In this experiment, a depth of $0m$ indicates a solid |
641 |
of $-2000m$ indicates open ocean. The matlab program |
wall and a depth of $-2000m$ indicates open ocean. The matlab |
642 |
{\it input/gendata.m} shows an example of how to generate a |
program {\it input/gendata.m} shows an example of how to generate a |
643 |
bathymetry file. |
bathymetry file. The variable \varlink{bathyFile}{bathyFile} is |
644 |
The variable |
read in the routine \varlink{INI\_PARMS}{INI_PARMS}. The bathymetry |
645 |
{\bf |
file is read in the routine |
646 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/179.htm> \end{rawhtml} |
|
647 |
bathyFile |
\fbox{ |
648 |
\begin{rawhtml} </A>\end{rawhtml} |
\begin{minipage}{5.0in} |
649 |
} |
{\it S/R INI\_DEPTHS}({\it ini\_depths.F}) |
650 |
is read in the routine |
\end{minipage} |
651 |
{\it |
} |
652 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
\filelink{ini\_depths.F}{model-src-ini_depths.F} |
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_DEPTHS}({\it ini\_depths.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/88.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
|
|
|
653 |
|
|
654 |
\item Line 50, |
\item Line 50, |
655 |
\begin{verbatim} |
\begin{verbatim} |
656 |
zonalWindFile='windx.sin_y' |
zonalWindFile='windx.sin_y' |
657 |
\end{verbatim} |
\end{verbatim} |
658 |
This line specifies the name of the file from which the x-direction |
This line specifies the name of the file from which the x-direction |
659 |
surface wind stress is read. This file is also a two-dimensional |
(zonal) surface wind stress is read. This file is also a |
660 |
($x,y$) map and is enumerated and formatted in the same manner as the |
two-dimensional ($x,y$) map and is enumerated and formatted in the |
661 |
bathymetry file. The matlab program {\it input/gendata.m} includes example |
same manner as the bathymetry file. The matlab program {\it |
662 |
code to generate a valid |
input/gendata.m} includes example code to generate a valid {\bf |
663 |
{\bf zonalWindFile} |
zonalWindFile} file. The variable |
664 |
file. |
\varlink{zonalWindFile}{zonalWindFile} is read in the routine |
665 |
The variable |
\varlink{INI\_PARMS}{INI_PARMS}. The wind-stress file is read in |
666 |
{\bf |
the routine |
667 |
\begin{rawhtml} <A href=../../../code_reference/vdb/names/13W.htm> \end{rawhtml} |
|
668 |
zonalWindFile |
\fbox{ |
669 |
\begin{rawhtml} </A>\end{rawhtml} |
\begin{minipage}{5.0in} |
670 |
} |
{\it S/R EXTERNAL\_FIELDS\_LOAD}({\it external\_fields\_load.F}) |
671 |
is read in the routine |
\end{minipage} |
672 |
{\it |
} |
673 |
\begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} |
\filelink{external\_fields\_load.F}{model-src-external_fields_load.F} |
|
INI\_PARMS |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R EXTERNAL\_FIELDS\_LOAD}({\it external\_fields\_load.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
{\bf |
|
|
\begin{rawhtml} <A href=../../../code_reference/vdb/code/75.htm> \end{rawhtml} |
|
|
goto code |
|
|
\begin{rawhtml} </A>\end{rawhtml} |
|
|
} |
|
674 |
|
|
675 |
\end{itemize} |
\end{itemize} |
676 |
|
|
677 |
\noindent other lines in the file {\it input/data} are standard values |
\noindent other lines in the file {\it input/data} are standard values. |
|
that are described in the MITgcm Getting Started and MITgcm Parameters |
|
|
notes. |
|
678 |
|
|
679 |
\begin{rawhtml}<PRE>\end{rawhtml} |
\begin{rawhtml}<PRE>\end{rawhtml} |
680 |
\begin{small} |
\begin{small} |
683 |
\begin{rawhtml}</PRE>\end{rawhtml} |
\begin{rawhtml}</PRE>\end{rawhtml} |
684 |
|
|
685 |
\subsubsection{File {\it input/data.pkg}} |
\subsubsection{File {\it input/data.pkg}} |
686 |
|
\label{www:tutorials} |
687 |
|
|
688 |
This file uses standard default values and does not contain |
This file uses standard default values and does not contain |
689 |
customisations for this experiment. |
customisations for this experiment. |
690 |
|
|
691 |
\subsubsection{File {\it input/eedata}} |
\subsubsection{File {\it input/eedata}} |
692 |
|
\label{www:tutorials} |
693 |
|
|
694 |
This file uses standard default values and does not contain |
This file uses standard default values and does not contain |
695 |
customisations for this experiment. |
customisations for this experiment. |
696 |
|
|
697 |
\subsubsection{File {\it input/windx.sin\_y}} |
\subsubsection{File {\it input/windx.sin\_y}} |
698 |
|
\label{www:tutorials} |
699 |
|
|
700 |
The {\it input/windx.sin\_y} file specifies a two-dimensional ($x,y$) |
The {\it input/windx.sin\_y} file specifies a two-dimensional ($x,y$) |
701 |
map of wind stress ,$\tau_{x}$, values. The units used are $Nm^{-2}$. |
map of wind stress ,$\tau_{x}$, values. The units used are $Nm^{-2}$ |
702 |
Although $\tau_{x}$ is only a function of $y$n in this experiment |
(the default for MITgcm). Although $\tau_{x}$ is only a function of |
703 |
this file must still define a complete two-dimensional map in order |
latitude, $y$, in this experiment this file must still define a |
704 |
to be compatible with the standard code for loading forcing fields |
complete two-dimensional map in order to be compatible with the |
705 |
in MITgcm. The included matlab program {\it input/gendata.m} gives a complete |
standard code for loading forcing fields in MITgcm (routine {\it |
706 |
code for creating the {\it input/windx.sin\_y} file. |
EXTERNAL\_FIELDS\_LOAD}. The included matlab program {\it |
707 |
|
input/gendata.m} gives a complete code for creating the {\it |
708 |
|
input/windx.sin\_y} file. |
709 |
|
|
710 |
\subsubsection{File {\it input/topog.box}} |
\subsubsection{File {\it input/topog.box}} |
711 |
|
\label{www:tutorials} |
712 |
|
|
713 |
|
|
714 |
The {\it input/topog.box} file specifies a two-dimensional ($x,y$) |
The {\it input/topog.box} file specifies a two-dimensional ($x,y$) |
715 |
map of depth values. For this experiment values are either |
map of depth values. For this experiment values are either |
716 |
$0m$ or $-2000\,{\rm m}$, corresponding respectively to a wall or to deep |
$0~{\rm m}$ or $-2000\,{\rm m}$, corresponding respectively to a wall or to deep |
717 |
ocean. The file contains a raw binary stream of data that is enumerated |
ocean. The file contains a raw binary stream of data that is enumerated |
718 |
in the same way as standard MITgcm two-dimensional, horizontal arrays. |
in the same way as standard MITgcm two-dimensional, horizontal arrays. |
719 |
The included matlab program {\it input/gendata.m} gives a complete |
The included matlab program {\it input/gendata.m} gives a complete |
720 |
code for creating the {\it input/topog.box} file. |
code for creating the {\it input/topog.box} file. |
721 |
|
|
722 |
\subsubsection{File {\it code/SIZE.h}} |
\subsubsection{File {\it code/SIZE.h}} |
723 |
|
\label{www:tutorials} |
724 |
|
|
725 |
Two lines are customized in this file for the current experiment |
Two lines are customized in this file for the current experiment |
726 |
|
|
747 |
\end{small} |
\end{small} |
748 |
|
|
749 |
\subsubsection{File {\it code/CPP\_OPTIONS.h}} |
\subsubsection{File {\it code/CPP\_OPTIONS.h}} |
750 |
|
\label{www:tutorials} |
751 |
|
|
752 |
This file uses standard default values and does not contain |
This file uses standard default values and does not contain |
753 |
customisations for this experiment. |
customisations for this experiment. |
754 |
|
|
755 |
|
|
756 |
\subsubsection{File {\it code/CPP\_EEOPTIONS.h}} |
\subsubsection{File {\it code/CPP\_EEOPTIONS.h}} |
757 |
|
\label{www:tutorials} |
758 |
|
|
759 |
This file uses standard default values and does not contain |
This file uses standard default values and does not contain |
760 |
customisations for this experiment. |
customisations for this experiment. |
761 |
|
|
762 |
\subsubsection{Other Files } |
\subsubsection{Other Files } |
763 |
|
\label{www:tutorials} |
764 |
|
|
765 |
Other files relevant to this experiment are |
Other files relevant to this experiment are |
766 |
\begin{itemize} |
\begin{itemize} |
773 |
\end{itemize} |
\end{itemize} |
774 |
|
|
775 |
\subsection{Running The Example} |
\subsection{Running The Example} |
776 |
|
\label{www:tutorials} |
777 |
\label{SEC:running_the_example} |
\label{SEC:running_the_example} |
778 |
|
|
779 |
\subsubsection{Code Download} |
\subsubsection{Code Download} |
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\label{www:tutorials} |
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|
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In order to run the examples you must first download the code distribution. |
In order to run the examples you must first download the code distribution. |
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Instructions for downloading the code can be found in the Getting Started |
Instructions for downloading the code can be found in section |
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Guide \cite{MITgcm_Getting_Started}. |
\ref{sect:obtainingCode}. |
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\subsubsection{Experiment Location} |
\subsubsection{Experiment Location} |
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\label{www:tutorials} |
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This example experiments is located under the release sub-directory |
This example experiments is located under the release sub-directory |
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\vspace{5mm} |
\vspace{5mm} |
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{\it verification/exp1/ } |
{\it verification/exp2/ } |
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|
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\subsubsection{Running the Experiment} |
\subsubsection{Running the Experiment} |
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\label{www:tutorials} |
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|
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To run the experiment |
To run the experiment |
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% pwd |
% pwd |
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\end{verbatim} |
\end{verbatim} |
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|
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You shold see a response on the screen ending in |
You should see a response on the screen ending in |
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{\it verification/exp1/input } |
{\it verification/exp2/input } |
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|
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\item Run the genmake script to create the experiment {\it Makefile} |
\item Run the genmake script to create the experiment {\it Makefile} |