| 20 | 
 to simulate a baroclinic ocean gyre in spherical | 
 to simulate a baroclinic ocean gyre in spherical | 
| 21 | 
 polar coordinates. The barotropic | 
 polar coordinates. The barotropic | 
| 22 | 
 example experiment in section \ref{sec:eg-baro} | 
 example experiment in section \ref{sec:eg-baro} | 
| 23 | 
 ilustrated how to configure the code for a single layer  | 
 illustrated how to configure the code for a single layer  | 
| 24 | 
 simulation in a cartesian grid. In this example a similar physical problem | 
 simulation in a Cartesian grid. In this example a similar physical problem | 
| 25 | 
 is simulated, but the code is now configured | 
 is simulated, but the code is now configured | 
| 26 | 
 for four layers and in a spherical polar coordinate system. | 
 for four layers and in a spherical polar coordinate system. | 
| 27 | 
  | 
  | 
| 29 | 
  | 
  | 
| 30 | 
 This example experiment demonstrates using the MITgcm to simulate | 
 This example experiment demonstrates using the MITgcm to simulate | 
| 31 | 
 a baroclinic, wind-forced, ocean gyre circulation. The experiment  | 
 a baroclinic, wind-forced, ocean gyre circulation. The experiment  | 
| 32 | 
 is a numerical rendition of the gyre circulation problem simliar | 
 is a numerical rendition of the gyre circulation problem similar | 
| 33 | 
 to the problems described analytically by Stommel in 1966  | 
 to the problems described analytically by Stommel in 1966  | 
| 34 | 
 \cite{Stommel66} and numerically in Holland et. al \cite{Holland75}. | 
 \cite{Stommel66} and numerically in Holland et. al \cite{Holland75}. | 
| 35 | 
 \\ | 
 \\ | 
| 62 | 
 \\ | 
 \\ | 
| 63 | 
  | 
  | 
| 64 | 
 Figure \ref{FIG:simulation_config} | 
 Figure \ref{FIG:simulation_config} | 
| 65 | 
 summarises the configuration simulated. | 
 summarizes the configuration simulated. | 
| 66 | 
 In contrast to the example in section \ref{sec:eg-baro}, the  | 
 In contrast to the example in section \ref{sec:eg-baro}, the  | 
| 67 | 
 current experiment simulates a spherical polar domain. As indicated | 
 current experiment simulates a spherical polar domain. As indicated | 
| 68 | 
 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 | 
| 69 | 
 in a locally orthoganal coordinate $(x,y,z)$. For this experiment description  | 
 in a locally orthogonal coordinate $(x,y,z)$. For this experiment description  | 
| 70 | 
 of this document the local orthogonal model coordinate $(x,y,z)$ is synonomous  | 
 the local orthogonal model coordinate $(x,y,z)$ is synonymous  | 
| 71 | 
 with the spherical polar coordinate shown in figure  | 
 with the coordinates $(\lambda,\varphi,r)$ shown in figure | 
| 72 | 
 \ref{fig:spherical-polar-coord} | 
 \ref{fig:spherical-polar-coord} | 
| 73 | 
 \\ | 
 \\ | 
| 74 | 
  | 
  | 
| 118 | 
 \end{figure} | 
 \end{figure} | 
| 119 | 
  | 
  | 
| 120 | 
 \subsection{Equations solved} | 
 \subsection{Equations solved} | 
| 121 | 
  | 
 For this problem | 
| 122 | 
 The implicit free surface {\bf HPE} form of the  | 
 the implicit free surface, {\bf HPE} (see section \ref{sec:hydrostatic_and_quasi-hydrostatic_forms}) form of the  | 
| 123 | 
 equations described in Marshall et. al \cite{Marshall97a} is  | 
 equations described in Marshall et. al \cite{Marshall97a} are | 
| 124 | 
 employed. The flow is three-dimensional with just temperature, $\theta$, as  | 
 employed. The flow is three-dimensional with just temperature, $\theta$, as  | 
| 125 | 
 an active tracer.  The equation of state is linear. | 
 an active tracer.  The equation of state is linear. | 
| 126 | 
 A horizontal laplacian operator $\nabla_{h}^2$ provides viscous | 
 A horizontal Laplacian operator $\nabla_{h}^2$ provides viscous | 
| 127 | 
 dissipation and provides a diffusive sub-grid scale closure for the  | 
 dissipation and provides a diffusive sub-grid scale closure for the  | 
| 128 | 
 temperature equation. A wind-stress momentum forcing is added to the momentum  | 
 temperature equation. A wind-stress momentum forcing is added to the momentum  | 
| 129 | 
 equation for the zonal flow, $u$. Other terms in the model | 
 equation for the zonal flow, $u$. Other terms in the model | 
| 130 | 
 are explicitly switched off for this experiement configuration (see section | 
 are explicitly switched off for this experiment configuration (see section | 
| 131 | 
 \ref{SEC:eg_fourl_code_config} ). This yields an active set of equations | 
 \ref{SEC:eg_fourl_code_config} ). This yields an active set of equations | 
| 132 | 
 solved in this configuration, written in spherical polar coordinates as  | 
 solved in this configuration, written in spherical polar coordinates as  | 
| 133 | 
 follows | 
 follows | 
| 185 | 
 part due to variations in density, $\rho^{\prime}$, integrated | 
 part due to variations in density, $\rho^{\prime}$, integrated | 
| 186 | 
 through the water column. | 
 through the water column. | 
| 187 | 
  | 
  | 
| 188 | 
 The suffices ${s},{i}$ indicate surface and interior of the domain. | 
 The suffices ${s},{i}$ indicate surface layer and the interior of the domain. | 
| 189 | 
 The windstress forcing, ${\cal F}_{\lambda}$, is applied in the surface layer  | 
 The windstress forcing, ${\cal F}_{\lambda}$, is applied in the surface layer  | 
| 190 | 
 by a source term in the zonal momentum equation. In the ocean interior | 
 by a source term in the zonal momentum equation. In the ocean interior | 
| 191 | 
 this term is zero. | 
 this term is zero. | 
| 210 | 
 Vertically the  | 
 Vertically the  | 
| 211 | 
 model is configured with four layers with constant depth,  | 
 model is configured with four layers with constant depth,  | 
| 212 | 
 $\Delta z$, of $500$~m. The internal, locally orthogonal, model coordinate  | 
 $\Delta z$, of $500$~m. The internal, locally orthogonal, model coordinate  | 
| 213 | 
 variables $x$ and $y$ are initialised from the values of | 
 variables $x$ and $y$ are initialized from the values of | 
| 214 | 
 $\lambda$, $\varphi$, $\Delta \lambda$ and $\Delta \varphi$ in | 
 $\lambda$, $\varphi$, $\Delta \lambda$ and $\Delta \varphi$ in | 
| 215 | 
 radians according to | 
 radians according to | 
| 216 | 
  | 
  | 
| 248 | 
 is evaluated prognostically. The centered second-order scheme with | 
 is evaluated prognostically. The centered second-order scheme with | 
| 249 | 
 Adams-Bashforth time stepping described in section  | 
 Adams-Bashforth time stepping described in section  | 
| 250 | 
 \ref{sec:tracer_equations_abII} is used to step forward the temperature  | 
 \ref{sec:tracer_equations_abII} is used to step forward the temperature  | 
| 251 | 
 equation. The pressure forces that drive the fluid motions, ( | 
 equation. Prognostic terms in | 
| 252 | 
  | 
 the momentum equations are solved using flux form as | 
| 253 | 
  | 
 described in section \ref{sec:flux-form_momentum_eqautions}. | 
| 254 | 
  | 
 The pressure forces that drive the fluid motions, ( | 
| 255 | 
 $\frac{\partial p^{'}}{\partial \lambda}$ 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  | 
| 256 | 
 elevation $\eta$ and the hydrostatic pressure. The hydrostatic part of the  | 
 elevation $\eta$ and the hydrostatic pressure. The hydrostatic part of the  | 
| 257 | 
 pressure is evaluated explicitly by integrating density. The sea-surface | 
 pressure is diagnosed explicitly by integrating density. The sea-surface | 
| 258 | 
 height, $\eta$, is solved for implicitly as described in section  | 
 height, $\eta$, is diagnosed using an implicit scheme. The pressure | 
| 259 | 
 \ref{sect:pressure-method-linear-backward}. | 
 field solution method is described in sections | 
| 260 | 
  | 
 \ref{sect:pressure-method-linear-backward} and  | 
| 261 | 
  | 
 \ref{sec:finding_the_pressure_field}. | 
| 262 | 
  | 
  | 
| 263 | 
 \subsubsection{Numerical Stability Criteria} | 
 \subsubsection{Numerical Stability Criteria} | 
| 264 | 
  | 
  | 
| 265 | 
 The laplacian dissipation coefficient, $A_{h}$, is set to $400 m s^{-1}$. | 
 The Laplacian viscosity coefficient, $A_{h}$, is set to $400 m s^{-1}$. | 
| 266 | 
 This value is chosen to yield a Munk layer width \cite{Adcroft_thesis}, | 
 This value is chosen to yield a Munk layer width, | 
| 267 | 
  | 
  | 
| 268 | 
 \begin{eqnarray} | 
 \begin{eqnarray} | 
| 269 | 
 \label{EQ:munk_layer} | 
 \label{EQ:munk_layer} | 
| 271 | 
 \end{eqnarray} | 
 \end{eqnarray} | 
| 272 | 
  | 
  | 
| 273 | 
 \noindent  of $\approx 100$km. This is greater than the model | 
 \noindent  of $\approx 100$km. This is greater than the model | 
| 274 | 
 resolution in mid-latitudes $\Delta x$, ensuring that the frictional  | 
 resolution in mid-latitudes  | 
| 275 | 
  | 
 $\Delta x=r \cos(\varphi) \Delta \lambda \approx 80~{\rm km}$ at | 
| 276 | 
  | 
 $\varphi=45^{\circ}$, ensuring that the frictional  | 
| 277 | 
 boundary layer is well resolved. | 
 boundary layer is well resolved. | 
 | 
  | 
  | 
| 278 | 
 \\ | 
 \\ | 
| 279 | 
  | 
  | 
| 280 | 
 \noindent The model is stepped forward with a  | 
 \noindent The model is stepped forward with a  | 
| 281 | 
 time step $\delta t=1200$secs. With this time step the stability  | 
 time step $\delta t=1200$secs. With this time step the stability  | 
| 282 | 
 parameter to the horizontal laplacian friction \cite{Adcroft_thesis} | 
 parameter to the horizontal Laplacian friction | 
| 283 | 
  | 
  | 
| 284 | 
 \begin{eqnarray} | 
 \begin{eqnarray} | 
| 285 | 
 \label{EQ:laplacian_stability} | 
 \label{EQ:laplacian_stability} | 
| 287 | 
 \end{eqnarray} | 
 \end{eqnarray} | 
| 288 | 
  | 
  | 
| 289 | 
 \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 | 
| 290 | 
 for stability.  | 
 for stability for this term under ABII time-stepping. | 
| 291 | 
 \\ | 
 \\ | 
| 292 | 
  | 
  | 
| 293 | 
 \noindent The vertical dissipation coefficient, $A_{z}$, is set to  | 
 \noindent The vertical dissipation coefficient, $A_{z}$, is set to  | 
| 305 | 
 \\ | 
 \\ | 
| 306 | 
  | 
  | 
| 307 | 
 \noindent The numerical stability for inertial oscillations | 
 \noindent The numerical stability for inertial oscillations | 
 | 
 \cite{Adcroft_thesis}  | 
  | 
| 308 | 
  | 
  | 
| 309 | 
 \begin{eqnarray} | 
 \begin{eqnarray} | 
| 310 | 
 \label{EQ:inertial_stability} | 
 \label{EQ:inertial_stability} | 
| 315 | 
 limit for stability. | 
 limit for stability. | 
| 316 | 
 \\ | 
 \\ | 
| 317 | 
  | 
  | 
| 318 | 
 \noindent The advective CFL \cite{Adcroft_thesis} for a extreme maximum  | 
 \noindent The advective CFL for a extreme maximum  | 
| 319 | 
 horizontal flow | 
 horizontal flow | 
| 320 | 
 speed of $ | \vec{u} | = 2 ms^{-1}$ | 
 speed of $ | \vec{u} | = 2 ms^{-1}$ | 
| 321 | 
  | 
  | 
| 322 | 
 \begin{eqnarray} | 
 \begin{eqnarray} | 
| 323 | 
 \label{EQ:cfl_stability} | 
 \label{EQ:cfl_stability} | 
| 324 | 
 S_{a} = \frac{| \vec{u} | \delta t}{ \Delta x} | 
 C_{a} = \frac{| \vec{u} | \delta t}{ \Delta x} | 
| 325 | 
 \end{eqnarray} | 
 \end{eqnarray} | 
| 326 | 
  | 
  | 
| 327 | 
 \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  | 
| 328 | 
 limit of 0.5. | 
 limit of 0.5. | 
| 329 | 
 \\ | 
 \\ | 
| 330 | 
  | 
  | 
| 331 | 
 \noindent The stability parameter for internal gravity waves  | 
 \noindent The stability parameter for internal gravity waves | 
| 332 | 
 \cite{Adcroft_thesis} | 
 propagating at $2~{\rm m}~{\rm s}^{-1}$  | 
| 333 | 
  | 
  | 
| 334 | 
 \begin{eqnarray} | 
 \begin{eqnarray} | 
| 335 | 
 \label{EQ:igw_stability} | 
 \label{EQ:igw_stability} | 
| 336 | 
 S_{c} = \frac{c_{g} \delta t}{ \Delta x} | 
 S_{c} = \frac{c_{g} \delta t}{ \Delta x} | 
| 337 | 
 \end{eqnarray} | 
 \end{eqnarray} | 
| 338 | 
  | 
  | 
| 339 | 
 \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 | 
| 340 | 
 stability limit of 0.25. | 
 stability limit of 0.25. | 
| 341 | 
    | 
    | 
| 342 | 
 \subsection{Code Configuration} | 
 \subsection{Code Configuration} | 
| 343 | 
 \label{SEC:eg_fourl_code_config} | 
 \label{SEC:eg_fourl_code_config} | 
| 344 | 
  | 
  | 
| 345 | 
 The model configuration for this experiment resides under the  | 
 The model configuration for this experiment resides under the  | 
| 346 | 
 directory {\it verification/exp1/}.  The experiment files  | 
 directory {\it verification/exp2/}.  The experiment files  | 
| 347 | 
 \begin{itemize} | 
 \begin{itemize} | 
| 348 | 
 \item {\it input/data} | 
 \item {\it input/data} | 
| 349 | 
 \item {\it input/data.pkg} | 
 \item {\it input/data.pkg} | 
| 355 | 
 \item {\it code/SIZE.h}.  | 
 \item {\it code/SIZE.h}.  | 
| 356 | 
 \end{itemize} | 
 \end{itemize} | 
| 357 | 
 contain the code customisations and parameter settings for this  | 
 contain the code customisations and parameter settings for this  | 
| 358 | 
 experiements. Below we describe the customisations | 
 experiments. Below we describe the customisations | 
| 359 | 
 to these files associated with this experiment. | 
 to these files associated with this experiment. | 
| 360 | 
  | 
  | 
| 361 | 
 \subsubsection{File {\it input/data}} | 
 \subsubsection{File {\it input/data}} | 
| 372 | 
 the initial and reference values of potential temperature at each model | 
 the initial and reference values of potential temperature at each model | 
| 373 | 
 level in units of $^{\circ}$C. | 
 level in units of $^{\circ}$C. | 
| 374 | 
 The entries are ordered from surface to depth. For each | 
 The entries are ordered from surface to depth. For each | 
| 375 | 
 depth level the inital and reference profiles will be uniform in | 
 depth level the initial and reference profiles will be uniform in | 
| 376 | 
 $x$ and $y$. The values specified here are read into the | 
 $x$ and $y$. The values specified here are read into the | 
| 377 | 
 variable  | 
 variable  | 
| 378 | 
 {\bf | 
 {\bf | 
| 418 | 
  | 
  | 
| 419 | 
 \item Line 6,  | 
 \item Line 6,  | 
| 420 | 
 \begin{verbatim} viscAz=1.E-2, \end{verbatim}  | 
 \begin{verbatim} viscAz=1.E-2, \end{verbatim}  | 
| 421 | 
 this line sets the vertical laplacian dissipation coefficient to | 
 this line sets the vertical Laplacian dissipation coefficient to | 
| 422 | 
 $1 \times 10^{-2} {\rm m^{2}s^{-1}}$. Boundary conditions | 
 $1 \times 10^{-2} {\rm m^{2}s^{-1}}$. Boundary conditions | 
| 423 | 
 for this operator are specified later.  | 
 for this operator are specified later.  | 
| 424 | 
 The variable  | 
 The variable  | 
| 438 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/names/PF.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/names/PF.htm> \end{rawhtml} | 
| 439 | 
 viscAr | 
 viscAr | 
| 440 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 441 | 
 }. | 
 }. At each time step, the viscous term contribution to the momentum equations | 
| 442 | 
  | 
 is calculated in routine | 
| 443 | 
  | 
 {\it S/R CALC\_DIFFUSIVITY}. | 
| 444 | 
  | 
  | 
| 445 | 
 \fbox{ | 
 \fbox{ | 
| 446 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 471 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 472 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 473 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 474 | 
 }. | 
 } and applied in routines {\it CALC\_MOM\_RHS} and {\it CALC\_GW}. | 
| 475 | 
  | 
  | 
| 476 | 
 \fbox{ | 
 \fbox{ | 
| 477 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 514 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 515 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 516 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 517 | 
 }. | 
 } and the boundary condition is evaluated in routine | 
| 518 | 
  | 
 {\it S/R CALC\_MOM\_RHS}. | 
| 519 | 
  | 
  | 
| 520 | 
  | 
  | 
| 521 | 
 \fbox{ | 
 \fbox{ | 
| 547 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 548 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 549 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 550 | 
 }. | 
 } and is applied in the routine {\it S/R CALC\_MOM\_RHS}. | 
| 551 | 
  | 
  | 
| 552 | 
 \fbox{ | 
 \fbox{ | 
| 553 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 579 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 580 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 581 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 582 | 
 }. | 
 } and used in routine {\it S/R CALC\_GT}. | 
| 583 | 
  | 
  | 
| 584 | 
 \fbox{ \begin{minipage}{5.0in} | 
 \fbox{ \begin{minipage}{5.0in} | 
| 585 | 
 {\it S/R CALC\_GT}({\it calc\_gt.F}) | 
 {\it S/R CALC\_GT}({\it calc\_gt.F}) | 
| 615 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/names/PD.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/names/PD.htm> \end{rawhtml} | 
| 616 | 
 diffKrT | 
 diffKrT | 
| 617 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 618 | 
 }. | 
 } which is used in routine {\it S/R CALC\_DIFFUSIVITY}. | 
| 619 | 
  | 
  | 
| 620 | 
 \fbox{ \begin{minipage}{5.0in} | 
 \fbox{ \begin{minipage}{5.0in} | 
| 621 | 
 {\it S/R CALC\_DIFFUSIVITY}({\it calc\_diffusivity.F}) | 
 {\it S/R CALC\_DIFFUSIVITY}({\it calc\_diffusivity.F}) | 
| 646 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 647 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 648 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 649 | 
 }. | 
 }. The routine {\it S/R FIND\_RHO} makes use of {\bf tAlpha}. | 
| 650 | 
  | 
  | 
| 651 | 
 \fbox{ | 
 \fbox{ | 
| 652 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 675 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 676 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 677 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 678 | 
 }. | 
 }. The values of {\bf eosType} sets which formula in routine | 
| 679 | 
  | 
 {\it FIND\_RHO} is used to calculate density. | 
| 680 | 
  | 
  | 
| 681 | 
 \fbox{ | 
 \fbox{ | 
| 682 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 697 | 
 \end{verbatim} | 
 \end{verbatim} | 
| 698 | 
 This line requests that the simulation be performed in a  | 
 This line requests that the simulation be performed in a  | 
| 699 | 
 spherical polar coordinate system. It affects the interpretation of | 
 spherical polar coordinate system. It affects the interpretation of | 
| 700 | 
 grid inoput parameters, for exampl {\bf delX} and {\bf delY} and | 
 grid input parameters, for example {\bf delX} and {\bf delY} and | 
| 701 | 
 causes the grid generation routines to initialise an internal grid based | 
 causes the grid generation routines to initialize an internal grid based | 
| 702 | 
 on spherical polar geometry. | 
 on spherical polar geometry. | 
| 703 | 
 The variable | 
 The variable | 
| 704 | 
 {\bf | 
 {\bf | 
| 711 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 712 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 713 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 714 | 
 }. | 
 }. When set to {\bf .TRUE.} the settings of {\bf delX} and {\bf delY} are | 
| 715 | 
  | 
 taken to be in degrees. These values are used in the | 
| 716 | 
  | 
 routine {\it INI\_SPEHRICAL\_POLAR\_GRID}. | 
| 717 | 
  | 
  | 
| 718 | 
 \fbox{ | 
 \fbox{ | 
| 719 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 733 | 
 This line sets the southern boundary of the modeled | 
 This line sets the southern boundary of the modeled | 
| 734 | 
 domain to $0^{\circ}$ latitude. This value affects both the | 
 domain to $0^{\circ}$ latitude. This value affects both the | 
| 735 | 
 generation of the locally orthogonal grid that the model | 
 generation of the locally orthogonal grid that the model | 
| 736 | 
 uses internally and affects the initialisation of the coriolis force. | 
 uses internally and affects the initialization of the coriolis force. | 
| 737 | 
 Note - it is not required to set | 
 Note - it is not required to set | 
| 738 | 
 a longitude boundary, since the absolute longitude does | 
 a longitude boundary, since the absolute longitude does | 
| 739 | 
 not alter the kernel equation discretisation. | 
 not alter the kernel equation discretisation. | 
| 748 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 749 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 750 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 751 | 
 }. | 
 } and is used in routine {\it INI\_SPEHRICAL\_POLAR\_GRID}. | 
| 752 | 
  | 
  | 
| 753 | 
 \fbox{ | 
 \fbox{ | 
| 754 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 778 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 779 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 780 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 781 | 
 }. | 
 } and is used in routine {\it INI\_SPEHRICAL\_POLAR\_GRID}.  | 
| 782 | 
  | 
  | 
| 783 | 
 \fbox{ | 
 \fbox{ | 
| 784 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 808 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 809 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 810 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 811 | 
 }. | 
 } and is used in routine {\it INI\_SPEHRICAL\_POLAR\_GRID}.  | 
| 812 | 
  | 
  | 
| 813 | 
 \fbox{ | 
 \fbox{ | 
| 814 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 846 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/names/10Y.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/names/10Y.htm> \end{rawhtml} | 
| 847 | 
 delR | 
 delR | 
| 848 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 849 | 
 }.  | 
 } which is used in routine {\it INI\_VERTICAL\_GRID}. | 
| 850 | 
  | 
  | 
| 851 | 
 \fbox{ | 
 \fbox{ | 
| 852 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 885 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 886 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 887 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 888 | 
 }. | 
 }. The bathymetry file is read in the routine {\it INI\_DEPTHS}. | 
| 889 | 
  | 
  | 
| 890 | 
 \fbox{ | 
 \fbox{ | 
| 891 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 904 | 
 zonalWindFile='windx.sin_y' | 
 zonalWindFile='windx.sin_y' | 
| 905 | 
 \end{verbatim} | 
 \end{verbatim} | 
| 906 | 
 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 | 
| 907 | 
 surface wind stress is read. This file is also a two-dimensional | 
 (zonal) surface wind stress is read. This file is also a two-dimensional | 
| 908 | 
 ($x,y$) map and is enumerated and formatted in the same manner as the  | 
 ($x,y$) map and is enumerated and formatted in the same manner as the  | 
| 909 | 
 bathymetry file. The matlab program {\it input/gendata.m} includes example  | 
 bathymetry file. The matlab program {\it input/gendata.m} includes example  | 
| 910 | 
 code to generate a valid  | 
 code to generate a valid  | 
| 921 | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
 \begin{rawhtml} <A href=../../../code_reference/vdb/code/94.htm> \end{rawhtml} | 
| 922 | 
 INI\_PARMS | 
 INI\_PARMS | 
| 923 | 
 \begin{rawhtml} </A>\end{rawhtml} | 
 \begin{rawhtml} </A>\end{rawhtml} | 
| 924 | 
 }. | 
 }.  The wind-stress file is read in the routine  | 
| 925 | 
  | 
 {\it EXTERNAL\_FIELDS\_LOAD}. | 
| 926 | 
  | 
  | 
| 927 | 
 \fbox{ | 
 \fbox{ | 
| 928 | 
 \begin{minipage}{5.0in} | 
 \begin{minipage}{5.0in} | 
| 937 | 
  | 
  | 
| 938 | 
 \end{itemize} | 
 \end{itemize} | 
| 939 | 
  | 
  | 
| 940 | 
 \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. | 
  | 
| 941 | 
  | 
  | 
| 942 | 
 \begin{rawhtml}<PRE>\end{rawhtml} | 
 \begin{rawhtml}<PRE>\end{rawhtml} | 
| 943 | 
 \begin{small} | 
 \begin{small} | 
| 958 | 
 \subsubsection{File {\it input/windx.sin\_y}} | 
 \subsubsection{File {\it input/windx.sin\_y}} | 
| 959 | 
  | 
  | 
| 960 | 
 The {\it input/windx.sin\_y} file specifies a two-dimensional ($x,y$)  | 
 The {\it input/windx.sin\_y} file specifies a two-dimensional ($x,y$)  | 
| 961 | 
 map of wind stress ,$\tau_{x}$, values. The units used are $Nm^{-2}$. | 
 map of wind stress ,$\tau_{x}$, values. The units used are $Nm^{-2}$ (the | 
| 962 | 
 Although $\tau_{x}$ is only a function of $y$n in this experiment | 
 default for MITgcm). | 
| 963 | 
  | 
 Although $\tau_{x}$ is only a function of latitude, $y$, | 
| 964 | 
  | 
 in this experiment | 
| 965 | 
 this file must still define a complete two-dimensional map in order | 
 this file must still define a complete two-dimensional map in order | 
| 966 | 
 to be compatible with the standard code for loading forcing fields  | 
 to be compatible with the standard code for loading forcing fields  | 
| 967 | 
 in MITgcm. The included matlab program {\it input/gendata.m} gives a complete | 
 in MITgcm (routine {\it EXTERNAL\_FIELDS\_LOAD}. | 
| 968 | 
  | 
 The included matlab program {\it input/gendata.m} gives a complete | 
| 969 | 
 code for creating the {\it input/windx.sin\_y} file. | 
 code for creating the {\it input/windx.sin\_y} file. | 
| 970 | 
  | 
  | 
| 971 | 
 \subsubsection{File {\it input/topog.box}} | 
 \subsubsection{File {\it input/topog.box}} | 
| 973 | 
  | 
  | 
| 974 | 
 The {\it input/topog.box} file specifies a two-dimensional ($x,y$)  | 
 The {\it input/topog.box} file specifies a two-dimensional ($x,y$)  | 
| 975 | 
 map of depth values. For this experiment values are either | 
 map of depth values. For this experiment values are either | 
| 976 | 
 $0m$ 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 | 
| 977 | 
 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 | 
| 978 | 
 in the same way as standard MITgcm two-dimensional, horizontal arrays. | 
 in the same way as standard MITgcm two-dimensional, horizontal arrays. | 
| 979 | 
 The included matlab program {\it input/gendata.m} gives a complete | 
 The included matlab program {\it input/gendata.m} gives a complete | 
| 1034 | 
 \subsubsection{Code Download} | 
 \subsubsection{Code Download} | 
| 1035 | 
  | 
  | 
| 1036 | 
  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. | 
| 1037 | 
 Instructions for downloading the code can be found in the Getting Started | 
 Instructions for downloading the code can be found in section | 
| 1038 | 
 Guide \cite{MITgcm_Getting_Started}. | 
 \ref{sect:obtainingCode}. | 
| 1039 | 
  | 
  | 
| 1040 | 
 \subsubsection{Experiment Location} | 
 \subsubsection{Experiment Location} | 
| 1041 | 
  | 
  | 
| 1042 | 
  This example experiments is located under the release sub-directory | 
  This example experiments is located under the release sub-directory | 
| 1043 | 
  | 
  | 
| 1044 | 
 \vspace{5mm} | 
 \vspace{5mm} | 
| 1045 | 
 {\it verification/exp1/ } | 
 {\it verification/exp2/ } | 
| 1046 | 
  | 
  | 
| 1047 | 
 \subsubsection{Running the Experiment} | 
 \subsubsection{Running the Experiment} | 
| 1048 | 
  | 
  | 
| 1061 | 
 % pwd | 
 % pwd | 
| 1062 | 
 \end{verbatim} | 
 \end{verbatim} | 
| 1063 | 
  | 
  | 
| 1064 | 
  You shold see a response on the screen ending in | 
  You should see a response on the screen ending in | 
| 1065 | 
  | 
  | 
| 1066 | 
 {\it verification/exp1/input } | 
 {\it verification/exp2/input } | 
| 1067 | 
  | 
  | 
| 1068 | 
  | 
  | 
| 1069 | 
 \item Run the genmake script to create the experiment {\it Makefile} | 
 \item Run the genmake script to create the experiment {\it Makefile} |