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\section{Global Ocean Simulation at 4$^\circ$ Resolution} |
\section[Global Ocean MITgcm Example]{Global Ocean Simulation at $4^\circ$ Resolution} |
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\label{www:tutorials} |
%\label{www:tutorials} |
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\label{sect:eg-global} |
\label{sec:eg-global} |
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\begin{rawhtml} |
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<!-- CMIREDIR:eg-global: --> |
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\begin{center} |
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(in directory: {\it verification/tutorial\_global\_oce\_latlon/}) |
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\end{center} |
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\bodytext{bgcolor="#FFFFFFFF"} |
\bodytext{bgcolor="#FFFFFFFF"} |
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%\begin{center} |
\noindent {\bf WARNING: the description of this experiment is not complete. |
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In particular, many parameters are not yet described.}\\ |
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%\begin{center} |
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%{\Large \bf Using MITgcm to Simulate Global Climatological Ocean Circulation |
%{\Large \bf Using MITgcm to Simulate Global Climatological Ocean Circulation |
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%At Four Degree Resolution with Asynchronous Time Stepping} |
%At Four Degree Resolution with Asynchronous Time Stepping} |
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%{\large May 2001} |
%{\large May 2001} |
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%\end{center} |
%\end{center} |
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This example experiment demonstrates using the MITgcm to simulate the |
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This example experiment demonstrates using the MITgcm to simulate |
planetary ocean circulation. The simulation is configured with |
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the planetary ocean circulation. The simulation is configured |
realistic geography and bathymetry on a $4^{\circ} \times 4^{\circ}$ |
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with realistic geography and bathymetry on a |
spherical polar grid. The files for this experiment are in the |
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$4^{\circ} \times 4^{\circ}$ spherical polar grid. |
verification directory under tutorial\_global\_oce\_latlon. Fifteen |
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Twenty levels are used in the vertical, ranging in thickness |
levels are used in the vertical, ranging in thickness from $50\,{\rm |
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from $50\,{\rm m}$ at the surface to $815\,{\rm m}$ at depth, |
m}$ at the surface to $690\,{\rm m}$ at depth, giving a maximum |
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giving a maximum model depth of $6\,{\rm km}$. |
model depth of $5200\,{\rm m}$. |
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At this resolution, the configuration |
Different time-steps are used to accelerate the convergence to |
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can be integrated forward for thousands of years on a single |
equilibrium \cite[]{bryan:84} so that, at this resolution, |
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processor desktop computer. |
the configuration can be integrated forward for thousands of years |
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on a single processor desktop computer. |
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\\ |
\\ |
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\subsection{Overview} |
\subsection{Overview} |
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\label{www:tutorials} |
%\label{www:tutorials} |
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The model is forced with climatological wind stress data and surface |
The model is forced with climatological wind stress data from |
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flux data from DaSilva \cite{DaSilva94}. Climatological data |
\citet{trenberth90} and NCEP surface flux data from |
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from Levitus \cite{Levitus94} is used to initialize the model hydrography. |
\citet{kalnay96}. Climatological data \citep{Levitus94} is |
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Levitus seasonal climatology data is also used throughout the calculation |
used to initialize the model hydrography. \citeauthor{Levitus94} seasonal |
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to provide additional air-sea fluxes. |
climatology data is also used throughout the calculation to provide |
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These fluxes are combined with the DaSilva climatological estimates of |
additional air-sea fluxes. These fluxes are combined with the NCEP |
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surface heat flux and fresh water, resulting in a mixed boundary |
climatological estimates of surface heat flux, resulting in a mixed |
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condition of the style described in Haney \cite{Haney}. |
boundary condition of the style described in \citet{Haney}. |
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Altogether, this yields the following forcing applied |
Altogether, this yields the following forcing applied in the model |
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in the model surface layer. |
surface layer. |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:eg-global-global_forcing} |
\label{eq:eg-global-global_forcing} |
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\label{EQ:eg-global-global_forcing_fu} |
\label{eq:eg-global-global_forcing_fu} |
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{\cal F}_{u} & = & \frac{\tau_{x}}{\rho_{0} \Delta z_{s}} |
{\cal F}_{u} & = & \frac{\tau_{x}}{\rho_{0} \Delta z_{s}} |
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\\ |
\\ |
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\label{EQ:eg-global-global_forcing_fv} |
\label{eq:eg-global-global_forcing_fv} |
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{\cal F}_{v} & = & \frac{\tau_{y}}{\rho_{0} \Delta z_{s}} |
{\cal F}_{v} & = & \frac{\tau_{y}}{\rho_{0} \Delta z_{s}} |
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\\ |
\\ |
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\label{EQ:eg-global-global_forcing_ft} |
\label{eq:eg-global-global_forcing_ft} |
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{\cal F}_{\theta} & = & - \lambda_{\theta} ( \theta - \theta^{\ast} ) |
{\cal F}_{\theta} & = & - \lambda_{\theta} ( \theta - \theta^{\ast} ) |
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- \frac{1}{C_{p} \rho_{0} \Delta z_{s}}{\cal Q} |
- \frac{1}{C_{p} \rho_{0} \Delta z_{s}}{\cal Q} |
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\\ |
\\ |
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\label{EQ:eg-global-global_forcing_fs} |
\label{eq:eg-global-global_forcing_fs} |
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{\cal F}_{s} & = & - \lambda_{s} ( S - S^{\ast} ) |
{\cal F}_{s} & = & - \lambda_{s} ( S - S^{\ast} ) |
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+ \frac{S_{0}}{\Delta z_{s}}({\cal E} - {\cal P} - {\cal R}) |
+ \frac{S_{0}}{\Delta z_{s}}({\cal E} - {\cal P} - {\cal R}) |
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\end{eqnarray} |
\end{eqnarray} |
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$\cal{Q}$ and $\cal{E}-\cal{P}-\cal{R}$. The wind stress fields ($\tau_x$, $\tau_y$) |
$\cal{Q}$ and $\cal{E}-\cal{P}-\cal{R}$. The wind stress fields ($\tau_x$, $\tau_y$) |
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have units of ${\rm N}~{\rm m}^{-2}$. The temperature forcing fields |
have units of ${\rm N}~{\rm m}^{-2}$. The temperature forcing fields |
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($\theta^{\ast}$ and $Q$) have units of $^{\circ}{\rm C}$ and ${\rm W}~{\rm m}^{-2}$ |
($\theta^{\ast}$ and $Q$) have units of $^{\circ}{\rm C}$ and ${\rm W}~{\rm m}^{-2}$ |
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respectively. The salinity forcing fields ($S^{\ast}$ and |
respectively. The salinity forcing fields ($S^{\ast}$ and |
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$\cal{E}-\cal{P}-\cal{R}$) have units of ${\rm ppt}$ and ${\rm m}~{\rm s}^{-1}$ |
$\cal{E}-\cal{P}-\cal{R}$) have units of ${\rm ppt}$ and ${\rm m}~{\rm s}^{-1}$ |
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respectively. The source files and procedures for ingesting this data into the |
respectively. The source files and procedures for ingesting this data into the |
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simulation are described in the experiment configuration discussion in section |
simulation are described in the experiment configuration discussion in section |
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\ref{SEC:eg-global-clim_ocn_examp_exp_config}. |
\ref{sec:eg-global-clim_ocn_examp_exp_config}. |
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\subsection{Discrete Numerical Configuration} |
\subsection{Discrete Numerical Configuration} |
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\label{www:tutorials} |
%\label{www:tutorials} |
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The model is configured in hydrostatic form. The domain is discretised with |
The model is configured in hydrostatic form. The domain is |
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a uniform grid spacing in latitude and longitude on the sphere |
discretised with a uniform grid spacing in latitude and longitude on |
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$\Delta \phi=\Delta \lambda=4^{\circ}$, so |
the sphere $\Delta \phi=\Delta \lambda=4^{\circ}$, so that there are |
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that there are ninety grid cells in the zonal and forty in the |
ninety grid cells in the zonal and forty in the meridional |
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meridional direction. The internal model coordinate variables |
direction. The internal model coordinate variables $x$ and $y$ are |
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$x$ and $y$ are initialized according to |
initialized according to |
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\begin{eqnarray} |
\begin{eqnarray} |
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x=r\cos(\phi),~\Delta x & = &r\cos(\Delta \phi) \\ |
x=r\cos(\phi),~\Delta x & = &r\cos(\Delta \phi) \\ |
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y=r\lambda,~\Delta y &= &r\Delta \lambda |
y=r\lambda,~\Delta y &= &r\Delta \lambda |
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\end{eqnarray} |
\end{eqnarray} |
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Arctic polar regions are not |
Arctic polar regions are not |
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included in this experiment. Meridionally the model extends from |
included in this experiment. Meridionally the model extends from |
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$80^{\circ}{\rm S}$ to $80^{\circ}{\rm N}$. |
$80^{\circ}{\rm S}$ to $80^{\circ}{\rm N}$. |
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Vertically the model is configured with twenty layers with the |
Vertically the model is configured with fifteen layers with the |
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following thicknesses |
following thicknesses: |
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$\Delta z_{1} = 50\,{\rm m},\, |
$\Delta z_{1} = 50\,{\rm m},$\\ |
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\Delta z_{2} = 50\,{\rm m},\, |
$\Delta z_{2} = 70\,{\rm m},\, |
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\Delta z_{3} = 55\,{\rm m},\, |
\Delta z_{3} = 100\,{\rm m},\, |
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\Delta z_{4} = 60\,{\rm m},\, |
\Delta z_{4} = 140\,{\rm m},\, |
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\Delta z_{5} = 65\,{\rm m},\, |
\Delta z_{5} = 190\,{\rm m},\, |
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$ |
\Delta z_{6} = 240\,{\rm m},\, |
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$ |
\Delta z_{7} = 290\,{\rm m},\, |
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\Delta z_{6}~=~70\,{\rm m},\, |
\Delta z_{8} = 340\,{\rm m},$\\ |
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\Delta z_{7}~=~80\,{\rm m},\, |
$\Delta z_{9} = 390\,{\rm m},\, |
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\Delta z_{8}~=95\,{\rm m},\, |
\Delta z_{10}= 440\,{\rm m},\, |
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\Delta z_{9}=120\,{\rm m},\, |
\Delta z_{11}= 490\,{\rm m},\, |
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\Delta z_{10}=155\,{\rm m},\, |
\Delta z_{12}= 540\,{\rm m},\, |
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$ |
\Delta z_{13}= 590\,{\rm m},\, |
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$ |
\Delta z_{14}= 640\,{\rm m},\, |
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\Delta z_{11}=200\,{\rm m},\, |
\Delta z_{15}= 690\,{\rm m}$\\ |
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\Delta z_{12}=260\,{\rm m},\, |
(here the numeric subscript indicates the model level index number, ${\tt k}$) to |
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\Delta z_{13}=320\,{\rm m},\, |
give a total depth, $H$, of $-5200{\rm m}$. |
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\Delta z_{14}=400\,{\rm m},\, |
The implicit free surface form of the pressure equation described in |
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\Delta z_{15}=480\,{\rm m},\, |
\citet{marshall:97a} is employed. A Laplacian operator, $\nabla^2$, provides viscous |
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\Delta z_{16}=570\,{\rm m},\, |
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\Delta z_{17}=655\,{\rm m},\, |
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\Delta z_{18}=725\,{\rm m},\, |
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\Delta z_{19}=775\,{\rm m},\, |
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\Delta z_{20}=815\,{\rm m} |
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$ (here the numeric subscript indicates the model level index number, ${\tt k}$) to |
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give a total depth, $H$, of $-5450{\rm m}$. |
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The implicit free surface form of the pressure equation described in Marshall et. al |
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\cite{marshall:97a} is employed. A Laplacian operator, $\nabla^2$, provides viscous |
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dissipation. Thermal and haline diffusion is also represented by a Laplacian operator. |
dissipation. Thermal and haline diffusion is also represented by a Laplacian operator. |
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Wind-stress forcing is added to the momentum equations in (\ref{EQ:eg-global-model_equations}) |
Wind-stress forcing is added to the momentum equations in (\ref{eq:eg-global-model_equations}) |
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for both the zonal flow, $u$ and the meridional flow $v$, according to equations |
for both the zonal flow, $u$ and the meridional flow $v$, according to equations |
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(\ref{EQ:eg-global-global_forcing_fu}) and (\ref{EQ:eg-global-global_forcing_fv}). |
(\ref{eq:eg-global-global_forcing_fu}) and (\ref{eq:eg-global-global_forcing_fv}). |
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Thermodynamic forcing inputs are added to the equations |
Thermodynamic forcing inputs are added to the equations |
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in (\ref{EQ:eg-global-model_equations}) for |
in (\ref{eq:eg-global-model_equations}) for |
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potential temperature, $\theta$, and salinity, $S$, according to equations |
potential temperature, $\theta$, and salinity, $S$, according to equations |
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(\ref{EQ:eg-global-global_forcing_ft}) and (\ref{EQ:eg-global-global_forcing_fs}). |
(\ref{eq:eg-global-global_forcing_ft}) and (\ref{eq:eg-global-global_forcing_fs}). |
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This produces a set of equations solved in this configuration as follows: |
This produces a set of equations solved in this configuration as follows: |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:eg-global-model_equations} |
\label{eq:eg-global-model_equations} |
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\frac{Du}{Dt} - fv + |
\frac{Du}{Dt} - fv + |
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\frac{1}{\rho}\frac{\partial p^{'}}{\partial x} - |
\frac{1}{\rho}\frac{\partial p^{'}}{\partial x} - |
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\nabla_{h}\cdot A_{h}\nabla_{h}u - |
\nabla_{h}\cdot A_{h}\nabla_{h}u - |
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\frac{\partial}{\partial z}A_{z}\frac{\partial u}{\partial z} |
\frac{\partial}{\partial z}A_{z}\frac{\partial u}{\partial z} |
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& = & |
& = & |
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\begin{cases} |
\begin{cases} |
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{\cal F}_u & \text{(surface)} \\ |
{\cal F}_u & \text{(surface)} \\ |
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0 & \text{(interior)} |
0 & \text{(interior)} |
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\end{cases} |
\end{cases} |
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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^{'}}{\partial y} - |
\frac{1}{\rho}\frac{\partial p^{'}}{\partial y} - |
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\nabla_{h}\cdot A_{h}\nabla_{h}v - |
\nabla_{h}\cdot A_{h}\nabla_{h}v - |
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\frac{\partial}{\partial z}A_{z}\frac{\partial v}{\partial z} |
\frac{\partial}{\partial z}A_{z}\frac{\partial v}{\partial z} |
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& = & |
& = & |
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\begin{cases} |
\begin{cases} |
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{\cal F}_v & \text{(surface)} \\ |
{\cal F}_v & \text{(surface)} \\ |
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\\ |
\\ |
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\frac{D\theta}{Dt} - |
\frac{D\theta}{Dt} - |
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\nabla_{h}\cdot K_{h}\nabla_{h}\theta |
\nabla_{h}\cdot K_{h}\nabla_{h}\theta |
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- \frac{\partial}{\partial z}\Gamma(K_{z})\frac{\partial\theta}{\partial z} |
- \frac{\partial}{\partial z}\Gamma(K_{z})\frac{\partial\theta}{\partial z} |
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& = & |
& = & |
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\begin{cases} |
\begin{cases} |
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{\cal F}_\theta & \text{(surface)} \\ |
{\cal F}_\theta & \text{(surface)} \\ |
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\\ |
\\ |
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\frac{D s}{Dt} - |
\frac{D s}{Dt} - |
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\nabla_{h}\cdot K_{h}\nabla_{h}s |
\nabla_{h}\cdot K_{h}\nabla_{h}s |
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- \frac{\partial}{\partial z}\Gamma(K_{z})\frac{\partial s}{\partial z} |
- \frac{\partial}{\partial z}\Gamma(K_{z})\frac{\partial s}{\partial z} |
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& = & |
& = & |
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\begin{cases} |
\begin{cases} |
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{\cal F}_s & \text{(surface)} \\ |
{\cal F}_s & \text{(surface)} \\ |
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g\rho_{0} \eta + \int^{0}_{-z}\rho^{'} dz & = & p^{'} |
g\rho_{0} \eta + \int^{0}_{-z}\rho^{'} dz & = & p^{'} |
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\end{eqnarray} |
\end{eqnarray} |
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\noindent where $u=\frac{Dx}{Dt}=r \cos(\phi)\frac{D \lambda}{Dt}$ and |
\noindent where $u=\frac{Dx}{Dt}=r \cos(\phi)\frac{D \lambda}{Dt}$ and |
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$v=\frac{Dy}{Dt}=r \frac{D \phi}{Dt}$ |
$v=\frac{Dy}{Dt}=r \frac{D \phi}{Dt}$ |
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are the zonal and meridional components of the |
are the zonal and meridional components of the |
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flow vector, $\vec{u}$, on the sphere. As described in |
flow vector, $\vec{u}$, on the sphere. As described in |
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MITgcm Numerical Solution Procedure \ref{chap:discretization}, the time |
MITgcm Numerical Solution Procedure \ref{chap:discretization}, the time |
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evolution of potential temperature, $\theta$, equation is solved prognostically. |
evolution of potential temperature, $\theta$, equation is solved prognostically. |
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The total pressure, $p$, is diagnosed by summing pressure due to surface |
The total pressure, $p$, is diagnosed by summing pressure due to surface |
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elevation $\eta$ and the hydrostatic pressure. |
elevation $\eta$ and the hydrostatic pressure. |
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\\ |
\\ |
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\subsubsection{Numerical Stability Criteria} |
\subsubsection{Numerical Stability Criteria} |
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\label{www:tutorials} |
%\label{www:tutorials} |
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The Laplacian dissipation coefficient, $A_{h}$, is set to $5 \times 10^5 m s^{-1}$. |
The Laplacian dissipation coefficient, $A_{h}$, is set to $5 \times 10^5 m s^{-1}$. |
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This value is chosen to yield a Munk layer width \cite{adcroft:95}, |
This value is chosen to yield a Munk layer width \citep{adcroft:95}, |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:eg-global-munk_layer} |
\label{eq:eg-global-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 $\approx 600$km. This is greater than the model |
\noindent of $\approx 600$km. This is greater than the model |
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resolution in low-latitudes, $\Delta x \approx 400{\rm km}$, ensuring that the frictional |
resolution in low-latitudes, $\Delta x \approx 400{\rm km}$, ensuring that the frictional |
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boundary layer is adequately resolved. |
boundary layer is adequately 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 time step $\Delta |
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time step $\delta t_{\theta}=30~{\rm hours}$ for thermodynamic variables and |
t_{\theta}=24~{\rm hours}$ for thermodynamic variables and $\Delta |
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$\delta t_{v}=40~{\rm minutes}$ for momentum terms. With this time step, the stability |
t_{v}=30~{\rm minutes}$ for momentum terms. With this time step, |
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parameter to the horizontal Laplacian friction \cite{adcroft:95} |
the stability parameter to the horizontal Laplacian friction |
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\citep{adcroft:95} |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:eg-global-laplacian_stability} |
\label{eq:eg-global-laplacian_stability} |
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S_{l} = 4 \frac{A_{h} \delta t_{v}}{{\Delta x}^2} |
&& S_{l} = 4 \frac{A_{h} \Delta t_{v}}{{\Delta x}^2} |
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\end{eqnarray} |
\end{eqnarray} |
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\noindent evaluates to 0.16 at a latitude of $\phi=80^{\circ}$, which is below the |
\noindent evaluates to 0.6 at a latitude of $\phi=80^{\circ}$, which |
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0.3 upper limit for stability. The zonal grid spacing $\Delta x$ is smallest at |
is above the 0.3 upper limit for stability, but the zonal grid spacing |
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$\phi=80^{\circ}$ where $\Delta x=r\cos(\phi)\Delta \phi\approx 77{\rm km}$. |
$\Delta x$ is smallest at $\phi=80^{\circ}$ where $\Delta |
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\\ |
x=r\cos(\phi)\Delta \phi\approx 77{\rm km}$ and the stability |
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criterion is already met 1 grid cell equatorwards (at $\phi=76^{\circ}$). |
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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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$1\times10^{-3} {\rm m}^2{\rm s}^{-1}$. The associated stability limit |
$1\times10^{-3} {\rm m}^2{\rm s}^{-1}$. The associated stability limit |
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\begin{eqnarray} |
\begin{eqnarray} |
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\label{EQ:eg-global-laplacian_stability_z} |
\label{eq:eg-global-laplacian_stability_z} |
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S_{l} = 4 \frac{A_{z} \delta t_{v}}{{\Delta z}^2} |
&& S_{l} = 4 \frac{A_{z} \Delta t_{v}}{{\Delta z}^2} |
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\end{eqnarray} |
\end{eqnarray} |
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\noindent evaluates to $0.015$ for the smallest model |
\noindent evaluates to $0.0029$ for the smallest model |
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level spacing ($\Delta z_{1}=50{\rm m}$) which is again well below |
level spacing ($\Delta z_{1}=50{\rm m}$) which is well below |
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the upper stability limit. |
the upper stability limit. |
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\\ |
\\ |
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The values of the horizontal ($K_{h}$) and vertical ($K_{z}$) diffusion coefficients |
% The values of the horizontal ($K_{h}$) and vertical ($K_{z}$) diffusion coefficients |
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for both temperature and salinity are set to $1 \times 10^{3}~{\rm m}^{2}{\rm s}^{-1}$ |
% for both temperature and salinity are set to $1 \times 10^{3}~{\rm m}^{2}{\rm s}^{-1}$ |
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and $3 \times 10^{-5}~{\rm m}^{2}{\rm s}^{-1}$ respectively. The stability limit |
% and $3 \times 10^{-5}~{\rm m}^{2}{\rm s}^{-1}$ respectively. The stability limit |
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related to $K_{h}$ will be at $\phi=80^{\circ}$ where $\Delta x \approx 77 {\rm km}$. |
% related to $K_{h}$ will be at $\phi=80^{\circ}$ where $\Delta x \approx 77 {\rm km}$. |
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Here the stability parameter |
% Here the stability parameter |
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\begin{eqnarray} |
% \begin{eqnarray} |
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\label{EQ:eg-global-laplacian_stability_xtheta} |
% \label{eq:eg-global-laplacian_stability_xtheta} |
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S_{l} = \frac{4 K_{h} \delta t_{\theta}}{{\Delta x}^2} |
% S_{l} = \frac{4 K_{h} \Delta t_{\theta}}{{\Delta x}^2} |
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\end{eqnarray} |
% \end{eqnarray} |
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evaluates to $0.07$, well below the stability limit of $S_{l} \approx 0.5$. The |
% evaluates to $0.07$, well below the stability limit of $S_{l} \approx 0.5$. The |
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stability parameter related to $K_{z}$ |
% stability parameter related to $K_{z}$ |
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\begin{eqnarray} |
% \begin{eqnarray} |
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\label{EQ:eg-global-laplacian_stability_ztheta} |
% \label{eq:eg-global-laplacian_stability_ztheta} |
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S_{l} = \frac{4 K_{z} \delta t_{\theta}}{{\Delta z}^2} |
% S_{l} = \frac{4 K_{z} \Delta t_{\theta}}{{\Delta z}^2} |
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\end{eqnarray} |
% \end{eqnarray} |
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evaluates to $0.005$ for $\min(\Delta z)=50{\rm m}$, well below the stability limit |
% evaluates to $0.005$ for $\min(\Delta z)=50{\rm m}$, well below the stability limit |
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of $S_{l} \approx 0.5$. |
% of $S_{l} \approx 0.5$. |
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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:95} |
\citep{adcroft:95} |
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|
|
273 |
\begin{eqnarray} |
\begin{eqnarray} |
274 |
\label{EQ:eg-global-inertial_stability} |
\label{eq:eg-global-inertial_stability} |
275 |
S_{i} = f^{2} {\delta t_v}^2 |
&& S_{i} = f^{2} {\Delta t_v}^2 |
276 |
\end{eqnarray} |
\end{eqnarray} |
277 |
|
|
278 |
\noindent evaluates to $0.24$ for $f=2\omega\sin(80^{\circ})=1.43\times10^{-4}~{\rm s}^{-1}$, which is close to |
\noindent evaluates to $0.07$ for |
279 |
the $S_{i} < 1$ upper limit for stability. |
$f=2\omega\sin(80^{\circ})=1.43\times10^{-4}~{\rm s}^{-1}$, which is |
280 |
|
below the $S_{i} < 1$ upper limit for stability. |
281 |
\\ |
\\ |
282 |
|
|
283 |
\noindent The advective CFL \cite{adcroft:95} for a extreme maximum |
\noindent The advective CFL \citep{adcroft:95} for a extreme maximum |
284 |
horizontal flow |
horizontal flow |
285 |
speed of $ | \vec{u} | = 2 ms^{-1}$ |
speed of $ | \vec{u} | = 2 ms^{-1}$ |
286 |
|
|
287 |
\begin{eqnarray} |
\begin{eqnarray} |
288 |
\label{EQ:eg-global-cfl_stability} |
\label{eq:eg-global-cfl_stability} |
289 |
S_{a} = \frac{| \vec{u} | \delta t_{v}}{ \Delta x} |
&& S_{a} = \frac{| \vec{u} | \Delta t_{v}}{ \Delta x} |
290 |
\end{eqnarray} |
\end{eqnarray} |
291 |
|
|
292 |
\noindent evaluates to $6 \times 10^{-2}$. This is well below the stability |
\noindent evaluates to $5 \times 10^{-2}$. This is well below the stability |
293 |
limit of 0.5. |
limit of 0.5. |
294 |
\\ |
\\ |
295 |
|
|
296 |
\noindent The stability parameter for internal gravity waves propagating |
\noindent The stability parameter for internal gravity waves propagating |
297 |
with a maximum speed of $c_{g}=10~{\rm ms}^{-1}$ |
with a maximum speed of $c_{g}=10~{\rm ms}^{-1}$ |
298 |
\cite{adcroft:95} |
\citep{adcroft:95} |
299 |
|
|
300 |
\begin{eqnarray} |
\begin{eqnarray} |
301 |
\label{EQ:eg-global-gfl_stability} |
\label{eq:eg-global-gfl_stability} |
302 |
S_{c} = \frac{c_{g} \delta t_{v}}{ \Delta x} |
&& S_{c} = \frac{c_{g} \Delta t_{v}}{ \Delta x} |
303 |
\end{eqnarray} |
\end{eqnarray} |
304 |
|
|
305 |
\noindent evaluates to $3 \times 10^{-1}$. This is close to the linear |
\noindent evaluates to $2.3 \times 10^{-1}$. This is close to the linear |
306 |
stability limit of 0.5. |
stability limit of 0.5. |
307 |
|
|
308 |
\subsection{Experiment Configuration} |
\subsection{Experiment Configuration} |
309 |
\label{www:tutorials} |
%\label{www:tutorials} |
310 |
\label{SEC:eg-global-clim_ocn_examp_exp_config} |
\label{sec:eg-global-clim_ocn_examp_exp_config} |
311 |
|
|
312 |
The model configuration for this experiment resides under the |
The model configuration for this experiment resides under the |
313 |
directory {\it tutorial\_examples/global\_ocean\_circulation/}. |
directory {\it tutorial\_global\_oce\_latlon/}. The experiment files |
|
The experiment files |
|
314 |
|
|
315 |
\begin{itemize} |
\begin{itemize} |
316 |
\item {\it input/data} |
\item {\it input/data} |
317 |
\item {\it input/data.pkg} |
\item {\it input/data.pkg} |
318 |
\item {\it input/eedata}, |
\item {\it input/eedata}, |
319 |
\item {\it input/windx.bin}, |
\item {\it input/trenberth\_taux.bin}, |
320 |
\item {\it input/windy.bin}, |
\item {\it input/trenberth\_tauy.bin}, |
321 |
\item {\it input/salt.bin}, |
\item {\it input/lev\_s.bin}, |
322 |
\item {\it input/theta.bin}, |
\item {\it input/lev\_t.bin}, |
323 |
\item {\it input/SSS.bin}, |
\item {\it input/lev\_sss.bin}, |
324 |
\item {\it input/SST.bin}, |
\item {\it input/lev\_sst.bin}, |
325 |
\item {\it input/topog.bin}, |
\item {\it input/bathymetry.bin}, |
326 |
\item {\it code/CPP\_EEOPTIONS.h} |
%\item {\it code/CPP\_EEOPTIONS.h} |
327 |
\item {\it code/CPP\_OPTIONS.h}, |
%\item {\it code/CPP\_OPTIONS.h}, |
328 |
\item {\it code/SIZE.h}. |
\item {\it code/SIZE.h}. |
329 |
\end{itemize} |
\end{itemize} |
330 |
contain the code customizations and parameter settings for these |
contain the code customizations and parameter settings for these |
331 |
experiments. Below we describe the customizations |
experiments. Below we describe the customizations |
332 |
to these files associated with this experiment. |
to these files associated with this experiment. |
333 |
|
|
334 |
\subsubsection{Driving Datasets} |
\subsubsection{Driving Datasets} |
335 |
\label{www:tutorials} |
%\label{www:tutorials} |
336 |
|
|
337 |
Figures (\ref{FIG:sim_config_tclim}-\ref{FIG:sim_config_empmr}) show the |
%% New figures are included before |
338 |
relaxation temperature ($\theta^{\ast}$) and salinity ($S^{\ast}$) fields, |
%% Relaxation temperature |
339 |
the wind stress components ($\tau_x$ and $\tau_y$), the heat flux ($Q$) |
%\begin{figure} |
340 |
|
%\centering |
341 |
|
%\includegraphics[]{relax_temperature.eps} |
342 |
|
%\caption{Relaxation temperature for January} |
343 |
|
%\label{fig:relax_temperature} |
344 |
|
%\end{figure} |
345 |
|
|
346 |
|
%% Relaxation salinity |
347 |
|
%\begin{figure} |
348 |
|
%\centering |
349 |
|
%\includegraphics[]{relax_salinity.eps} |
350 |
|
%\caption{Relaxation salinity for January} |
351 |
|
%\label{fig:relax_salinity} |
352 |
|
%\end{figure} |
353 |
|
|
354 |
|
%% tau_x |
355 |
|
%\begin{figure} |
356 |
|
%\centering |
357 |
|
%\includegraphics[]{tau_x.eps} |
358 |
|
%\caption{zonal wind stress for January} |
359 |
|
%\label{fig:tau_x} |
360 |
|
%\end{figure} |
361 |
|
|
362 |
|
%% tau_y |
363 |
|
%\begin{figure} |
364 |
|
%\centering |
365 |
|
%\includegraphics[]{tau_y.eps} |
366 |
|
%\caption{meridional wind stress for January} |
367 |
|
%\label{fig:tau_y} |
368 |
|
%\end{figure} |
369 |
|
|
370 |
|
%% Qnet |
371 |
|
%\begin{figure} |
372 |
|
%\centering |
373 |
|
%\includegraphics[]{qnet.eps} |
374 |
|
%\caption{Heat flux for January} |
375 |
|
%\label{fig:qnet} |
376 |
|
%\end{figure} |
377 |
|
|
378 |
|
%% EmPmR |
379 |
|
%\begin{figure} |
380 |
|
%\centering |
381 |
|
%\includegraphics[]{empmr.eps} |
382 |
|
%\caption{Fresh water flux for January} |
383 |
|
%\label{fig:empmr} |
384 |
|
%\end{figure} |
385 |
|
|
386 |
|
%% Bathymetry |
387 |
|
%\begin{figure} |
388 |
|
%\centering |
389 |
|
%\includegraphics[]{bathymetry.eps} |
390 |
|
%\caption{Bathymetry} |
391 |
|
%\label{fig:bathymetry} |
392 |
|
%\end{figure} |
393 |
|
|
394 |
|
|
395 |
|
Figures (\ref{fig:sim_config_tclim_pcoord}-\ref{fig:sim_config_empmr_pcoord}) |
396 |
|
%(\ref{fig:sim_config_tclim}-\ref{fig:sim_config_empmr}) |
397 |
|
show the relaxation temperature ($\theta^{\ast}$) and salinity ($S^{\ast}$) |
398 |
|
fields, the wind stress components ($\tau_x$ and $\tau_y$), the heat flux ($Q$) |
399 |
and the net fresh water flux (${\cal E} - {\cal P} - {\cal R}$) used |
and the net fresh water flux (${\cal E} - {\cal P} - {\cal R}$) used |
400 |
in equations \ref{EQ:global_forcing_fu}-\ref{EQ:global_forcing_fs}. The figures |
in equations |
401 |
also indicate the lateral extent and coastline used in the experiment. |
(\ref{eq:eg-global-global_forcing_fu}-\ref{eq:eg-global-global_forcing_fs}). |
402 |
Figure ({\ref{FIG:model_bathymetry}) shows the depth contours of the model |
The figures also indicate the lateral extent and coastline used in the |
403 |
domain. |
experiment. Figure ({\it --- missing figure --- }) %ref{fig:model_bathymetry}) |
404 |
|
shows the depth contours of the model domain. |
405 |
|
|
406 |
\subsubsection{File {\it input/data}} |
\subsubsection{File {\it input/data}} |
407 |
\label{www:tutorials} |
%\label{www:tutorials} |
|
|
|
|
This file, reproduced completely below, specifies the main parameters |
|
|
for the experiment. The parameters that are significant for this configuration |
|
|
are |
|
|
|
|
|
\begin{itemize} |
|
|
|
|
|
\item Lines 7-10 and 11-14 |
|
|
\begin{verbatim} tRef= 16.0 , 15.2 , 14.5 , 13.9 , 13.3 , \end{verbatim} |
|
|
$\cdots$ \\ |
|
|
set reference values for potential |
|
|
temperature and salinity at each model level in units of $^{\circ}$C and |
|
|
${\rm ppt}$. The entries are ordered from surface to depth. |
|
|
Density is calculated from anomalies at each level evaluated |
|
|
with respect to the reference values set here.\\ |
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_THETA}({\it ini\_theta.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
|
|
|
\item Line 15, |
|
|
\begin{verbatim} viscAz=1.E-3, \end{verbatim} |
|
|
this line sets the vertical Laplacian dissipation coefficient to |
|
|
$1 \times 10^{-3} {\rm m^{2}s^{-1}}$. Boundary conditions |
|
|
for this operator are specified later. This variable is copied into |
|
|
model general vertical coordinate variable {\bf viscAr}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R CALC\_DIFFUSIVITY}({\it calc\_diffusivity.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 16, |
|
|
\begin{verbatim} |
|
|
viscAh=5.E5, |
|
|
\end{verbatim} |
|
|
this line sets the horizontal Laplacian frictional dissipation coefficient to |
|
|
$5 \times 10^{5} {\rm m^{2}s^{-1}}$. Boundary conditions |
|
|
for this operator are specified later. |
|
|
|
|
|
\item Lines 17, |
|
|
\begin{verbatim} |
|
|
no_slip_sides=.FALSE. |
|
|
\end{verbatim} |
|
|
this line selects a free-slip lateral boundary condition for |
|
|
the horizontal Laplacian friction operator |
|
|
e.g. $\frac{\partial u}{\partial y}$=0 along boundaries in $y$ and |
|
|
$\frac{\partial v}{\partial x}$=0 along boundaries in $x$. |
|
|
|
|
|
\item Lines 9, |
|
|
\begin{verbatim} |
|
|
no_slip_bottom=.TRUE. |
|
|
\end{verbatim} |
|
|
this line selects a no-slip boundary condition for bottom |
|
|
boundary condition in the vertical Laplacian friction operator |
|
|
e.g. $u=v=0$ at $z=-H$, where $H$ is the local depth of the domain. |
|
|
|
|
|
\item Line 19, |
|
|
\begin{verbatim} |
|
|
diffKhT=1.E3, |
|
|
\end{verbatim} |
|
|
this line sets the horizontal diffusion coefficient for temperature |
|
|
to $1000\,{\rm m^{2}s^{-1}}$. The boundary condition on this |
|
|
operator is $\frac{\partial}{\partial x}=\frac{\partial}{\partial y}=0$ on |
|
|
all boundaries. |
|
|
|
|
|
\item Line 20, |
|
|
\begin{verbatim} |
|
|
diffKzT=3.E-5, |
|
|
\end{verbatim} |
|
|
this line sets the vertical diffusion coefficient for temperature |
|
|
to $3 \times 10^{-5}\,{\rm m^{2}s^{-1}}$. The boundary |
|
|
condition on this operator is $\frac{\partial}{\partial z}=0$ at both |
|
|
the upper and lower boundaries. |
|
|
|
|
|
\item Line 21, |
|
|
\begin{verbatim} |
|
|
diffKhS=1.E3, |
|
|
\end{verbatim} |
|
|
this line sets the horizontal diffusion coefficient for salinity |
|
|
to $1000\,{\rm m^{2}s^{-1}}$. The boundary condition on this |
|
|
operator is $\frac{\partial}{\partial x}=\frac{\partial}{\partial y}=0$ on |
|
|
all boundaries. |
|
|
|
|
|
\item Line 22, |
|
|
\begin{verbatim} |
|
|
diffKzS=3.E-5, |
|
|
\end{verbatim} |
|
|
this line sets the vertical diffusion coefficient for salinity |
|
|
to $3 \times 10^{-5}\,{\rm m^{2}s^{-1}}$. The boundary |
|
|
condition on this operator is $\frac{\partial}{\partial z}=0$ at both |
|
|
the upper and lower boundaries. |
|
|
|
|
|
\item Lines 23-26 |
|
|
\begin{verbatim} |
|
|
beta=1.E-11, |
|
|
\end{verbatim} |
|
|
\vspace{-5mm}$\cdots$\\ |
|
|
These settings do not apply for this experiment. |
|
|
|
|
|
\item Line 27, |
|
|
\begin{verbatim} |
|
|
gravity=9.81, |
|
|
\end{verbatim} |
|
|
Sets the gravitational acceleration coefficient to $9.81{\rm m}{\rm s}^{-1}$.\\ |
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R CALC\_PHI\_HYD}~({\it calc\_phi\_hyd.F})\\ |
|
|
{\it S/R INI\_CG2D}~({\it ini\_cg2d.F})\\ |
|
|
{\it S/R INI\_CG3D}~({\it ini\_cg3d.F})\\ |
|
|
{\it S/R INI\_PARMS}~({\it ini\_parms.F})\\ |
|
|
{\it S/R SOLVE\_FOR\_PRESSURE}~({\it solve\_for\_pressure.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
|
|
|
\item Line 28-29, |
|
|
\begin{verbatim} |
|
|
rigidLid=.FALSE., |
|
|
implicitFreeSurface=.TRUE., |
|
|
\end{verbatim} |
|
|
Selects the barotropic pressure equation to be the implicit free surface |
|
|
formulation. |
|
|
|
|
|
\item Line 30, |
|
|
\begin{verbatim} |
|
|
eosType='POLY3', |
|
|
\end{verbatim} |
|
|
Selects the third order polynomial form of the equation of state.\\ |
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R FIND\_RHO}~({\it find\_rho.F})\\ |
|
|
{\it S/R FIND\_ALPHA}~({\it find\_alpha.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 31, |
|
|
\begin{verbatim} |
|
|
readBinaryPrec=32, |
|
|
\end{verbatim} |
|
|
Sets format for reading binary input datasets holding model fields to |
|
|
use 32-bit representation for floating-point numbers.\\ |
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R READ\_WRITE\_FLD}~({\it read\_write\_fld.F})\\ |
|
|
{\it S/R READ\_WRITE\_REC}~({\it read\_write\_rec.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 36, |
|
|
\begin{verbatim} |
|
|
cg2dMaxIters=1000, |
|
|
\end{verbatim} |
|
|
Sets maximum number of iterations the two-dimensional, conjugate |
|
|
gradient solver will use, {\bf irrespective of convergence |
|
|
criteria being met}.\\ |
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R CG2D}~({\it cg2d.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 37, |
|
|
\begin{verbatim} |
|
|
cg2dTargetResidual=1.E-13, |
|
|
\end{verbatim} |
|
|
Sets the tolerance which the two-dimensional, conjugate |
|
|
gradient solver will use to test for convergence in equation |
|
|
\ref{EQ:congrad_2d_resid} to $1 \times 10^{-13}$. |
|
|
Solver will iterate until |
|
|
tolerance falls below this value or until the maximum number of |
|
|
solver iterations is reached.\\ |
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R CG2D}~({\it cg2d.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 42, |
|
|
\begin{verbatim} |
|
|
startTime=0, |
|
|
\end{verbatim} |
|
|
Sets the starting time for the model internal time counter. |
|
|
When set to non-zero this option implicitly requests a |
|
|
checkpoint file be read for initial state. |
|
|
By default the checkpoint file is named according to |
|
|
the integer number of time steps in the {\bf startTime} value. |
|
|
The internal time counter works in seconds. |
|
|
|
|
|
\item Line 43, |
|
|
\begin{verbatim} |
|
|
endTime=2808000., |
|
|
\end{verbatim} |
|
|
Sets the time (in seconds) at which this simulation will terminate. |
|
|
At the end of a simulation a checkpoint file is automatically |
|
|
written so that a numerical experiment can consist of multiple |
|
|
stages. |
|
|
|
|
|
\item Line 44, |
|
|
\begin{verbatim} |
|
|
#endTime=62208000000, |
|
|
\end{verbatim} |
|
|
A commented out setting for endTime for a 2000 year simulation. |
|
|
|
|
|
\item Line 45, |
|
|
\begin{verbatim} |
|
|
deltaTmom=2400.0, |
|
|
\end{verbatim} |
|
|
Sets the timestep $\delta t_{v}$ used in the momentum equations to |
|
|
$20~{\rm mins}$. |
|
|
See section \ref{SEC:mom_time_stepping}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R TIMESTEP}({\it timestep.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 46, |
|
|
\begin{verbatim} |
|
|
tauCD=321428., |
|
|
\end{verbatim} |
|
|
Sets the D-grid to C-grid coupling time scale $\tau_{CD}$ used in the momentum equations. |
|
|
See section \ref{SEC:cd_scheme}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R INI\_PARMS}({\it ini\_parms.F})\\ |
|
|
{\it S/R CALC\_MOM\_RHS}({\it calc\_mom\_rhs.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 47, |
|
|
\begin{verbatim} |
|
|
deltaTtracer=108000., |
|
|
\end{verbatim} |
|
|
Sets the default timestep, $\delta t_{\theta}$, for tracer equations to |
|
|
$30~{\rm hours}$. |
|
|
See section \ref{SEC:tracer_time_stepping}. |
|
|
|
|
|
\fbox{ |
|
|
\begin{minipage}{5.0in} |
|
|
{\it S/R TIMESTEP\_TRACER}({\it timestep\_tracer.F}) |
|
|
\end{minipage} |
|
|
} |
|
|
|
|
|
\item Line 47, |
|
|
\begin{verbatim} |
|
|
bathyFile='topog.box' |
|
|
\end{verbatim} |
|
|
This line specifies the name of the file from which the domain |
|
|
bathymetry is read. This file is a two-dimensional ($x,y$) map of |
|
|
depths. This file is assumed to contain 64-bit binary numbers |
|
|
giving the depth of the model at each grid cell, ordered with the x |
|
|
coordinate varying fastest. The points are ordered from low coordinate |
|
|
to high coordinate for both axes. The units and orientation of the |
|
|
depths in this file are the same as used in the MITgcm code. In this |
|
|
experiment, a depth of $0m$ indicates a solid wall and a depth |
|
|
of $-2000m$ indicates open ocean. The matlab program |
|
|
{\it input/gendata.m} shows an example of how to generate a |
|
|
bathymetry file. |
|
|
|
|
|
|
|
|
\item Line 50, |
|
|
\begin{verbatim} |
|
|
zonalWindFile='windx.sin_y' |
|
|
\end{verbatim} |
|
|
This line specifies the name of the file from which the x-direction |
|
|
surface wind stress is read. This file is also a two-dimensional |
|
|
($x,y$) map and is enumerated and formatted in the same manner as the |
|
|
bathymetry file. The matlab program {\it input/gendata.m} includes example |
|
|
code to generate a valid |
|
|
{\bf zonalWindFile} |
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file. |
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\end{itemize} |
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408 |
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409 |
\noindent other lines in the file {\it input/data} are standard values |
\input{s_examples/global_oce_latlon/inp_data} |
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that are described in the MITgcm Getting Started and MITgcm Parameters |
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notes. |
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\begin{small} |
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\input{part3/case_studies/climatalogical_ogcm/input/data} |
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\end{small} |
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410 |
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411 |
\subsubsection{File {\it input/data.pkg}} |
\subsubsection{File {\it input/data.pkg}} |
412 |
\label{www:tutorials} |
%\label{www:tutorials} |
413 |
|
|
414 |
This file uses standard default values and does not contain |
This file uses standard default values and does not contain |
415 |
customisations for this experiment. |
customisations for this experiment. |
416 |
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|
417 |
\subsubsection{File {\it input/eedata}} |
\subsubsection{File {\it input/eedata}} |
418 |
\label{www:tutorials} |
%\label{www:tutorials} |
419 |
|
|
420 |
This file uses standard default values and does not contain |
This file uses standard default values and does not contain |
421 |
customisations for this experiment. |
customisations for this experiment. |
422 |
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|
423 |
\subsubsection{File {\it input/windx.sin\_y}} |
\subsubsection{Files{\it input/trenberth\_taux.bin} and {\it |
424 |
\label{www:tutorials} |
input/trenberth\_tauy.bin}} |
425 |
|
%\label{www:tutorials} |
426 |
The {\it input/windx.sin\_y} file specifies a two-dimensional ($x,y$) |
|
427 |
map of wind stress ,$\tau_{x}$, values. The units used are $Nm^{-2}$. |
The {\it input/trenberth\_taux.bin} and {\it |
428 |
Although $\tau_{x}$ is only a function of $y$n in this experiment |
input/trenberth\_tauy.bin} files specify a three-dimensional |
429 |
this file must still define a complete two-dimensional map in order |
($x,y,time$) map of wind stress, $(\tau_{x},\tau_{y})$, values |
430 |
to be compatible with the standard code for loading forcing fields |
\citep{trenberth90}. The units used are $Nm^{-2}$. |
431 |
in MITgcm. The included matlab program {\it input/gendata.m} gives a complete |
|
432 |
code for creating the {\it input/windx.sin\_y} file. |
\subsubsection{File {\it input/bathymetry.bin}} |
433 |
|
%\label{www:tutorials} |
434 |
\subsubsection{File {\it input/topog.box}} |
|
435 |
\label{www:tutorials} |
The {\it input/bathymetry.bin} file specifies a two-dimensional |
436 |
|
($x,y$) map of depth values. For this experiment values range |
437 |
|
between~$0$ and $-5200\,{\rm m}$, and have been derived from |
438 |
The {\it input/topog.box} file specifies a two-dimensional ($x,y$) |
ETOPO5. The file contains a raw binary stream of data that is |
439 |
map of depth values. For this experiment values are either |
enumerated in the same way as standard MITgcm two-dimensional, |
440 |
$0m$ or $-2000\,{\rm m}$, corresponding respectively to a wall or to deep |
horizontal arrays. |
|
ocean. The file contains a raw binary stream of data that is enumerated |
|
|
in the same way as standard MITgcm two-dimensional, horizontal arrays. |
|
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The included matlab program {\it input/gendata.m} gives a complete |
|
|
code for creating the {\it input/topog.box} file. |
|
441 |
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|
442 |
\subsubsection{File {\it code/SIZE.h}} |
\subsubsection{File {\it code/SIZE.h}} |
443 |
\label{www:tutorials} |
%\label{www:tutorials} |
|
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|
|
Two lines are customized in this file for the current experiment |
|
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\begin{itemize} |
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\item Line 39, |
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\begin{verbatim} sNx=60, \end{verbatim} this line sets |
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the lateral domain extent in grid points for the |
|
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axis aligned with the x-coordinate. |
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\item Line 40, |
|
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\begin{verbatim} sNy=60, \end{verbatim} this line sets |
|
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the lateral domain extent in grid points for the |
|
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axis aligned with the y-coordinate. |
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\item Line 49, |
|
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\begin{verbatim} Nr=4, \end{verbatim} this line sets |
|
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the vertical domain extent in grid points. |
|
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|
|
|
\end{itemize} |
|
444 |
|
|
445 |
\begin{small} |
\input{s_examples/global_oce_latlon/cod_SIZE.h} |
|
\input{part3/case_studies/climatalogical_ogcm/code/SIZE.h} |
|
|
\end{small} |
|
446 |
|
|
447 |
\subsubsection{File {\it code/CPP\_OPTIONS.h}} |
%\subsubsection{File {\it code/CPP\_OPTIONS.h}} |
448 |
\label{www:tutorials} |
%\label{www:tutorials} |
449 |
|
|
450 |
This file uses standard default values and does not contain |
%This file uses standard default values and does not contain |
451 |
customisations for this experiment. |
%customisations for this experiment. |
452 |
|
|
453 |
|
|
454 |
\subsubsection{File {\it code/CPP\_EEOPTIONS.h}} |
%\subsubsection{File {\it code/CPP\_EEOPTIONS.h}} |
455 |
\label{www:tutorials} |
%\label{www:tutorials} |
456 |
|
|
457 |
This file uses standard default values and does not contain |
%This file uses standard default values and does not contain |
458 |
customisations for this experiment. |
%customisations for this experiment. |
459 |
|
|
460 |
\subsubsection{Other Files } |
\subsubsection{Other Files } |
461 |
\label{www:tutorials} |
%\label{www:tutorials} |
462 |
|
|
463 |
Other files relevant to this experiment are |
% Other files relevant to this experiment are |
464 |
\begin{itemize} |
% \begin{itemize} |
465 |
\item {\it model/src/ini\_cori.F}. This file initializes the model |
% \item {\it model/src/ini\_cori.F}. This file initializes the model |
466 |
coriolis variables {\bf fCorU}. |
% coriolis variables {\bf fCorU}. |
467 |
\item {\it model/src/ini\_spherical\_polar\_grid.F} |
% \item {\it model/src/ini\_spherical\_polar\_grid.F} |
468 |
\item {\it model/src/ini\_parms.F}, |
% \item {\it model/src/ini\_parms.F}, |
469 |
\item {\it input/windx.sin\_y}, |
% \item {\it input/windx.sin\_y}, |
470 |
\end{itemize} |
% \end{itemize} |
471 |
contain the code customisations and parameter settings for this |
% contain the code customisations and parameter settings for this |
472 |
experiments. Below we describe the customisations |
% experiments. Below we describe the customisations |
473 |
to these files associated with this experiment. |
% to these files associated with this experiment. |