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Changeset 12065 for NEMO/branches/2019/dev_r10742_ENHANCE-12_SimonM-Tides/doc/latex/NEMO/subfiles/chap_model_basics_zstar.tex – NEMO

Ignore:
Timestamp:
2019-12-05T12:06:36+01:00 (4 years ago)
Author:
smueller
Message:

Synchronizing with /NEMO/trunk@12055 (ticket #2194)

Location:
NEMO/branches/2019/dev_r10742_ENHANCE-12_SimonM-Tides/doc
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5 edited

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  • NEMO/branches/2019/dev_r10742_ENHANCE-12_SimonM-Tides/doc/latex/NEMO/subfiles/chap_model_basics_zstar.tex

    r10544 r12065  
    22 
    33\begin{document} 
    4 % ================================================================ 
    5 % Chapter 1 Model Basics 
    6 % ================================================================ 
    7 % ================================================================ 
    8 % Curvilinear \zstar- \sstar-coordinate System 
    9 % ================================================================ 
     4 
    105\chapter{ essai \zstar \sstar} 
     6 
     7\thispagestyle{plain} 
     8 
     9\chaptertoc 
     10 
     11\paragraph{Changes record} ~\\ 
     12 
     13{\footnotesize 
     14  \begin{tabularx}{\textwidth}{l||X|X} 
     15    Release & Author(s) & Modifications \\ 
     16    \hline 
     17    {\em   4.0} & {\em ...} & {\em ...} \\ 
     18    {\em   3.6} & {\em ...} & {\em ...} \\ 
     19    {\em   3.4} & {\em ...} & {\em ...} \\ 
     20    {\em <=3.4} & {\em ...} & {\em ...} 
     21  \end{tabularx} 
     22} 
     23 
     24\clearpage 
     25 
     26%% ================================================================================================= 
    1127\section{Curvilinear \zstar- or \sstar coordinate system} 
    1228 
    13 % ------------------------------------------------------------------------------------------------------------- 
    14 % ???? 
    15 % ------------------------------------------------------------------------------------------------------------- 
    16  
    1729\colorbox{yellow}{ to be updated } 
    1830 
    1931In that case, the free surface equation is nonlinear, and the variations of volume are fully taken into account. 
    20 These coordinates systems is presented in a report \citep{Levier2007} available on the \NEMO web site.  
     32These coordinates systems is presented in a report \citep{levier.treguier.ea_rpt07} available on the \NEMO\ web site. 
    2133 
    2234\colorbox{yellow}{  end of to be updated} 
     
    2436% from MOM4p1 documentation 
    2537 
    26 To overcome problems with vanishing surface and/or bottom cells, we consider the zstar coordinate  
    27 \[ 
    28   % \label{eq:PE_} 
     38To overcome problems with vanishing surface and/or bottom cells, we consider the zstar coordinate 
     39\[ 
     40  % \label{eq:MBZ_PE_} 
    2941  z^\star = H \left( \frac{z-\eta}{H+\eta} \right) 
    3042\] 
     
    4052the surface height, it is clear that surfaces constant $z^\star$ are very similar to the depth surfaces. 
    4153These properties greatly reduce difficulties of computing the horizontal pressure gradient relative to 
    42 terrain following sigma models discussed in \autoref{subsec:PE_sco}.  
     54terrain following sigma models discussed in \autoref{subsec:MB_sco}. 
    4355Additionally, since $z^\star$ when $\eta = 0$, no flow is spontaneously generated in 
    4456an unforced ocean starting from rest, regardless the bottom topography. 
     
    4961neutral physics parameterizations in $z^\star$ models using the same techniques as in $z$-models 
    5062(see Chapters 13-16 of Griffies (2004) for a discussion of neutral physics in $z$-models, 
    51 as well as  \autoref{sec:LDF_slp} in this document for treatment in \NEMO).  
     63as well as  \autoref{sec:LDF_slp} in this document for treatment in \NEMO). 
    5264 
    5365The range over which $z^\star$ varies is time independent $-H \leq z^\star \leq 0$. 
    5466Hence, all cells remain nonvanishing, so long as the surface height maintains $\eta > ?H$. 
    55 This is a minor constraint relative to that encountered on the surface height when using $s = z$ or $s = z - \eta$.  
     67This is a minor constraint relative to that encountered on the surface height when using $s = z$ or $s = z - \eta$. 
    5668 
    5769Because $z^\star$ has a time independent range, all grid cells have static increments ds, 
    58 and the sum of the ver tical increments yields the time independent ocean depth %�k ds = H.  
     70and the sum of the ver tical increments yields the time independent ocean depth %�k ds = H. 
    5971The $z^\star$ coordinate is therefore invisible to undulations of the free surface, 
    6072since it moves along with the free surface. 
     
    6476Quite generally, the time independent range for the $z^\star$ coordinate is a very convenient property that 
    6577allows for a nearly arbitrary vertical resolution even in the presence of large amplitude fluctuations of 
    66 the surface height, again so long as $\eta > -H$.  
    67  
    68 %%% 
     78the surface height, again so long as $\eta > -H$. 
     79 
    6980%  essai update time splitting... 
    70 %%% 
    71  
    72 % ================================================================ 
    73 % Surface Pressure Gradient and Sea Surface Height 
    74 % ================================================================ 
    75 \section{Surface pressure gradient and sea surface heigth (\protect\mdl{dynspg})} 
    76 \label{sec:DYN_hpg_spg} 
    77 %-----------------------------------------nam_dynspg---------------------------------------------------- 
    78  
    79 %\nlst{nam_dynspg}  
    80 %------------------------------------------------------------------------------------------------------------ 
    81 Options are defined through the \ngn{nam\_dynspg} namelist variables. 
    82 The surface pressure gradient term is related to the representation of the free surface (\autoref{sec:PE_hor_pg}). 
     81 
     82%% ================================================================================================= 
     83\section[Surface pressure gradient and sea surface heigth (\textit{dynspg.F90})]{Surface pressure gradient and sea surface heigth (\protect\mdl{dynspg})} 
     84\label{sec:MBZ_dyn_hpg_spg} 
     85 
     86%\nlst{nam_dynspg} 
     87Options are defined through the \nam{_dynspg}{\_dynspg} namelist variables. 
     88The surface pressure gradient term is related to the representation of the free surface (\autoref{sec:MB_hor_pg}). 
    8389The main distinction is between the fixed volume case (linear free surface or rigid lid) and 
    8490the variable volume case (nonlinear free surface, \key{vvl} is active). 
    85 In the linear free surface case (\autoref{subsec:PE_free_surface}) and rigid lid (\autoref{PE_rigid_lid}), 
     91In the linear free surface case (\autoref{subsec:MB_free_surface}) and rigid lid (\autoref{PE_rigid_lid}), 
    8692the vertical scale factors $e_{3}$ are fixed in time, 
    87 while in the nonlinear case (\autoref{subsec:PE_free_surface}) they are time-dependent. 
     93while in the nonlinear case (\autoref{subsec:MB_free_surface}) they are time-dependent. 
    8894With both linear and nonlinear free surface, external gravity waves are allowed in the equations, 
    8995which imposes a very small time step when an explicit time stepping is used. 
    9096Two methods are proposed to allow a longer time step for the three-dimensional equations: 
    91 the filtered free surface, which is a modification of the continuous equations %(see \autoref{eq:PE_flt}), 
     97the filtered free surface, which is a modification of the continuous equations %(see \autoref{eq:MB_flt?}), 
    9298and the split-explicit free surface described below. 
    9399The extra term introduced in the filtered method is calculated implicitly, 
    94100so that the update of the next velocities is done in module \mdl{dynspg\_flt} and not in \mdl{dynnxt}. 
    95101 
    96 %------------------------------------------------------------- 
    97102% Explicit 
    98 %------------------------------------------------------------- 
    99 \subsubsection{Explicit (\protect\key{dynspg\_exp})} 
    100 \label{subsec:DYN_spg_exp} 
     103%% ================================================================================================= 
     104\subsubsection[Explicit (\texttt{\textbf{key\_dynspg\_exp}})]{Explicit (\protect\key{dynspg\_exp})} 
     105\label{subsec:MBZ_dyn_spg_exp} 
    101106 
    102107In the explicit free surface formulation, the model time step is chosen small enough to 
     
    104109The sea surface height is given by: 
    105110\begin{equation} 
    106   \label{eq:dynspg_ssh} 
     111  \label{eq:MBZ_dynspg_ssh} 
    107112  \frac{\partial \eta }{\partial t}\equiv \frac{\text{EMP}}{\rho_w }+\frac{1}{e_{1T} 
    108113    e_{2T} }\sum\limits_k {\left( {\delta_i \left[ {e_{2u} e_{3u} u} 
     
    114119and $\rho_w =1,000\,Kg.m^{-3}$ is the volumic mass of pure water. 
    115120The sea-surface height is evaluated using a leapfrog scheme in combination with an Asselin time filter, 
    116 (\ie the velocity appearing in (\autoref{eq:dynspg_ssh}) is centred in time (\textit{now} velocity).  
     121(\ie\ the velocity appearing in (\autoref{eq:DYN_spg_ssh}) is centred in time (\textit{now} velocity). 
    117122 
    118123The surface pressure gradient, also evaluated using a leap-frog scheme, is then simply given by: 
    119124\begin{equation} 
    120   \label{eq:dynspg_exp} 
     125  \label{eq:MBZ_dynspg_exp} 
    121126  \left\{ 
    122127    \begin{aligned} 
     
    125130    \end{aligned} 
    126131  \right. 
    127 \end{equation}  
     132\end{equation} 
    128133 
    129134Consistent with the linearization, a $\left. \rho \right|_{k=1} / \rho_o$ factor is omitted in 
    130 (\autoref{eq:dynspg_exp}).  
    131  
    132 %------------------------------------------------------------- 
     135(\autoref{eq:DYN_spg_exp}). 
     136 
    133137% Split-explicit time-stepping 
    134 %------------------------------------------------------------- 
    135 \subsubsection{Split-explicit time-stepping (\protect\key{dynspg\_ts})} 
    136 \label{subsec:DYN_spg_ts} 
    137 %--------------------------------------------namdom---------------------------------------------------- 
    138  
    139 \nlst{namdom}  
    140 %-------------------------------------------------------------------------------------------------------------- 
    141 The split-explicit free surface formulation used in OPA follows the one proposed by \citet{Griffies2004}. 
     138%% ================================================================================================= 
     139\subsubsection[Split-explicit time-stepping (\texttt{\textbf{key\_dynspg\_ts}})]{Split-explicit time-stepping (\protect\key{dynspg\_ts})} 
     140\label{subsec:MBZ_dyn_spg_ts} 
     141 
     142The split-explicit free surface formulation used in OPA follows the one proposed by \citet{Griffies2004?}. 
    142143The general idea is to solve the free surface equation with a small time step, 
    143144while the three dimensional prognostic variables are solved with a longer time step that 
    144 is a multiple of \np{rdtbt} in the \ngn{namdom} namelist (Figure III.3).  
    145  
    146 %>   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   > 
     145is a multiple of \np{rdtbt}{rdtbt} in the \nam{dom}{dom} namelist (Figure III.3). 
     146 
    147147\begin{figure}[!t] 
    148   \begin{center} 
    149     \includegraphics[width=0.90\textwidth]{Fig_DYN_dynspg_ts} 
    150     \caption{ 
    151       \protect\label{fig:DYN_dynspg_ts} 
    152       Schematic of the split-explicit time stepping scheme for the barotropic and baroclinic modes, 
    153       after \citet{Griffies2004}. 
    154       Time increases to the right. 
    155       Baroclinic time steps are denoted by $t-\Delta t$, $t, t+\Delta t$, and $t+2\Delta t$. 
    156       The curved line represents a leap-frog time step, 
    157       and the smaller barotropic time steps $N \Delta t=2\Delta t$ are denoted by the zig-zag line. 
    158       The vertically integrated forcing \textbf{M}(t) computed at 
    159       baroclinic time step t represents the interaction between the barotropic and baroclinic motions. 
    160       While keeping the total depth, tracer, and freshwater forcing fields fixed, 
    161       a leap-frog integration carries the surface height and vertically integrated velocity from 
    162       t to $t+2 \Delta t$ using N barotropic time steps of length $\Delta t$. 
    163       Time averaging the barotropic fields over the N+1 time steps (endpoints included) 
    164       centers the vertically integrated velocity at the baroclinic timestep $t+\Delta t$. 
    165       A baroclinic leap-frog time step carries the surface height to $t+\Delta t$ using the convergence of 
    166       the time averaged vertically integrated velocity taken from baroclinic time step t. 
    167     } 
    168   \end{center} 
     148  \centering 
     149  %\includegraphics[width=0.66\textwidth]{MBZ_DYN_dynspg_ts} 
     150  \caption[Schematic of the split-explicit time stepping scheme for 
     151  the barotropic and baroclinic modes, after \citet{Griffies2004?}]{ 
     152    Schematic of the split-explicit time stepping scheme for the barotropic and baroclinic modes, 
     153    after \citet{Griffies2004?}. 
     154    Time increases to the right. 
     155    Baroclinic time steps are denoted by $t-\Delta t$, $t, t+\Delta t$, and $t+2\Delta t$. 
     156    The curved line represents a leap-frog time step, 
     157    and the smaller barotropic time steps $N \Delta t=2\Delta t$ are denoted by the zig-zag line. 
     158    The vertically integrated forcing \textbf{M}(t) computed at 
     159    baroclinic time step t represents the interaction between the barotropic and baroclinic motions. 
     160    While keeping the total depth, tracer, and freshwater forcing fields fixed, 
     161    a leap-frog integration carries the surface height and vertically integrated velocity from 
     162    t to $t+2 \Delta t$ using N barotropic time steps of length $\Delta t$. 
     163    Time averaging the barotropic fields over the N+1 time steps (endpoints included) 
     164    centers the vertically integrated velocity at the baroclinic timestep $t+\Delta t$. 
     165    A baroclinic leap-frog time step carries the surface height to $t+\Delta t$ using 
     166    the convergence of the time averaged vertically integrated velocity taken from 
     167    baroclinic time step t.} 
     168  \label{fig:MBZ_dyn_dynspg_ts} 
    169169\end{figure} 
    170 %>   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   >   > 
    171170 
    172171The split-explicit formulation has a damping effect on external gravity waves, 
    173 which is weaker than the filtered free surface but still significant as shown by \citet{Levier2007} in 
    174 the case of an analytical barotropic Kelvin wave.  
     172which is weaker than the filtered free surface but still significant as shown by \citet{levier.treguier.ea_rpt07} in 
     173the case of an analytical barotropic Kelvin wave. 
    175174 
    176175%from griffies book: .....   copy past ! 
     
    183182We have 
    184183\[ 
    185   % \label{eq:DYN_spg_ts_eta} 
     184  % \label{eq:MBZ_dyn_spg_ts_eta} 
    186185  \eta^{(b)}(\tau,t_{n+1}) - \eta^{(b)}(\tau,t_{n+1}) (\tau,t_{n-1}) 
    187   = 2 \Delta t \left[-\nabla \cdot \textbf{U}^{(b)}(\tau,t_n) + \text{EMP}_w(\tau) \right]  
     186  = 2 \Delta t \left[-\nabla \cdot \textbf{U}^{(b)}(\tau,t_n) + \text{EMP}_w(\tau) \right] 
    188187\] 
    189188\begin{multline*} 
    190   % \label{eq:DYN_spg_ts_u} 
     189  % \label{eq:MBZ_dyn_spg_ts_u} 
    191190  \textbf{U}^{(b)}(\tau,t_{n+1}) - \textbf{U}^{(b)}(\tau,t_{n-1})  \\ 
    192191  = 2\Delta t \left[ - f \textbf{k} \times \textbf{U}^{(b)}(\tau,t_{n}) 
     
    202201the freshwater flux $\text{EMP}_w(\tau)$, and total depth of the ocean $H(\tau)$ are held for 
    203202the duration of the barotropic time stepping over a single cycle. 
    204 This is also the time that sets the barotropic time steps via  
    205 \[ 
    206   % \label{eq:DYN_spg_ts_t} 
    207   t_n=\tau+n\Delta t    
     203This is also the time that sets the barotropic time steps via 
     204\[ 
     205  % \label{eq:MBZ_dyn_spg_ts_t} 
     206  t_n=\tau+n\Delta t 
    208207\] 
    209208with $n$ an integer. 
    210 The density scaled surface pressure is evaluated via  
    211 \[ 
    212   % \label{eq:DYN_spg_ts_ps} 
     209The density scaled surface pressure is evaluated via 
     210\[ 
     211  % \label{eq:MBZ_dyn_spg_ts_ps} 
    213212  p_s^{(b)}(\tau,t_{n}) = 
    214213  \begin{cases} 
     
    217216  \end{cases} 
    218217\] 
    219 To get started, we assume the following initial conditions  
    220 \[ 
    221   % \label{eq:DYN_spg_ts_eta} 
     218To get started, we assume the following initial conditions 
     219\[ 
     220  % \label{eq:MBZ_dyn_spg_ts_eta} 
    222221  \begin{split} 
    223222    \eta^{(b)}(\tau,t_{n=0}) &= \overline{\eta^{(b)}(\tau)} \\ 
     
    225224  \end{split} 
    226225\] 
    227 with  
    228 \[ 
    229   % \label{eq:DYN_spg_ts_etaF} 
     226with 
     227\[ 
     228  % \label{eq:MBZ_dyn_spg_ts_etaF} 
    230229  \overline{\eta^{(b)}(\tau)} = \frac{1}{N+1} \sum\limits_{n=0}^N \eta^{(b)}(\tau-\Delta t,t_{n}) 
    231230\] 
     
    233232Likewise, 
    234233\[ 
    235   % \label{eq:DYN_spg_ts_u} 
     234  % \label{eq:MBZ_dyn_spg_ts_u} 
    236235  \textbf{U}^{(b)}(\tau,t_{n=0}) = \overline{\textbf{U}^{(b)}(\tau)} \\ \\ 
    237236  \textbf{U}(\tau,t_{n=1}) = \textbf{U}^{(b)}(\tau,t_{n=0}) + \Delta t \ \text{RHS}_{n=0} 
    238237\] 
    239 with  
    240 \[ 
    241   % \label{eq:DYN_spg_ts_u} 
     238with 
     239\[ 
     240  % \label{eq:MBZ_dyn_spg_ts_u} 
    242241  \overline{\textbf{U}^{(b)}(\tau)} = \frac{1}{N+1} \sum\limits_{n=0}^N\textbf{U}^{(b)}(\tau-\Delta t,t_{n}) 
    243242\] 
    244243the time averaged vertically integrated transport. 
    245 Notably, there is no Robert-Asselin time filter used in the barotropic portion of the integration.  
     244Notably, there is no Robert-Asselin time filter used in the barotropic portion of the integration. 
    246245 
    247246Upon reaching $t_{n=N} = \tau + 2\Delta \tau$ , the vertically integrated velocity is time averaged to 
    248 produce the updated vertically integrated velocity at baroclinic time $\tau + \Delta \tau$  
    249 \[ 
    250   % \label{eq:DYN_spg_ts_u} 
     247produce the updated vertically integrated velocity at baroclinic time $\tau + \Delta \tau$ 
     248\[ 
     249  % \label{eq:MBZ_dyn_spg_ts_u} 
    251250  \textbf{U}(\tau+\Delta t) = \overline{\textbf{U}^{(b)}(\tau+\Delta t)} 
    252251  = \frac{1}{N+1} \sum\limits_{n=0}^N\textbf{U}^{(b)}(\tau,t_{n}) 
    253252\] 
    254253The surface height on the new baroclinic time step is then determined via 
    255 a baroclinic leap-frog using the following form  
     254a baroclinic leap-frog using the following form 
    256255\begin{equation} 
    257   \label{eq:DYN_spg_ts_ssh} 
     256  \label{eq:MBZ_dyn_spg_ts_ssh} 
    258257  \eta(\tau+\Delta) - \eta^{F}(\tau-\Delta) = 2\Delta t \ \left[ - \nabla \cdot \textbf{U}(\tau) + \text{EMP}_w \right] 
    259258\end{equation} 
     
    261260The use of this "big-leap-frog" scheme for the surface height ensures compatibility between 
    262261the mass/volume budgets and the tracer budgets. 
    263 More discussion of this point is provided in Chapter 10 (see in particular Section 10.2).  
    264   
     262More discussion of this point is provided in Chapter 10 (see in particular Section 10.2). 
     263 
    265264In general, some form of time filter is needed to maintain integrity of the surface height field due to 
    266 the leap-frog splitting mode in equation \autoref{eq:DYN_spg_ts_ssh}. 
     265the leap-frog splitting mode in equation \autoref{eq:MBZ_dyn_spg_ts_ssh}. 
    267266We have tried various forms of such filtering, 
    268267with the following method discussed in Griffies et al. (2001) chosen due to its stability and 
    269 reasonably good maintenance of tracer conservation properties (see ??)  
     268reasonably good maintenance of tracer conservation properties (see ??) 
    270269 
    271270\begin{equation} 
    272   \label{eq:DYN_spg_ts_sshf} 
     271  \label{eq:MBZ_dyn_spg_ts_sshf} 
    273272  \eta^{F}(\tau-\Delta) =  \overline{\eta^{(b)}(\tau)} 
    274273\end{equation} 
    275 Another approach tried was  
    276  
    277 \[ 
    278   % \label{eq:DYN_spg_ts_sshf2} 
     274Another approach tried was 
     275 
     276\[ 
     277  % \label{eq:MBZ_dyn_spg_ts_sshf2} 
    279278  \eta^{F}(\tau-\Delta) = \eta(\tau) 
    280279  + (\alpha/2) \left[\overline{\eta^{(b)}}(\tau+\Delta t) 
     
    285284This isolation allows for an easy check that tracer conservation is exact when eliminating tracer and 
    286285surface height time filtering (see ?? for more complete discussion). 
    287 However, in the general case with a non-zero $\alpha$, the filter \autoref{eq:DYN_spg_ts_sshf} was found to 
    288 be more conservative, and so is recommended.  
    289  
    290 %------------------------------------------------------------- 
    291 % Filtered formulation  
    292 %------------------------------------------------------------- 
    293 \subsubsection{Filtered formulation (\protect\key{dynspg\_flt})} 
    294 \label{subsec:DYN_spg_flt} 
    295  
    296 The filtered formulation follows the \citet{Roullet2000} implementation. 
     286However, in the general case with a non-zero $\alpha$, the filter \autoref{eq:MBZ_dyn_spg_ts_sshf} was found to 
     287be more conservative, and so is recommended. 
     288 
     289% Filtered formulation 
     290%% ================================================================================================= 
     291\subsubsection[Filtered formulation (\texttt{\textbf{key\_dynspg\_flt}})]{Filtered formulation (\protect\key{dynspg\_flt})} 
     292\label{subsec:MBZ_dyn_spg_flt} 
     293 
     294The filtered formulation follows the \citet{Roullet2000?} implementation. 
    297295The extra term introduced in the equations (see {\S}I.2.2) is solved implicitly. 
    298296The elliptic solvers available in the code are documented in \autoref{chap:MISC}. 
    299 The amplitude of the extra term is given by the namelist variable \np{rnu}. 
    300 The default value is 1, as recommended by \citet{Roullet2000} 
    301  
    302 \colorbox{red}{\np{rnu}\forcode{ = 1} to be suppressed from namelist !} 
    303  
    304 %------------------------------------------------------------- 
    305 % Non-linear free surface formulation  
    306 %------------------------------------------------------------- 
    307 \subsection{Non-linear free surface formulation (\protect\key{vvl})} 
    308 \label{subsec:DYN_spg_vvl} 
     297The amplitude of the extra term is given by the namelist variable \np{rnu}{rnu}. 
     298The default value is 1, as recommended by \citet{Roullet2000?} 
     299 
     300\colorbox{red}{\np[=1]{rnu}{rnu} to be suppressed from namelist !} 
     301 
     302% Non-linear free surface formulation 
     303%% ================================================================================================= 
     304\subsection[Non-linear free surface formulation (\texttt{\textbf{key\_vvl}})]{Non-linear free surface formulation (\protect\key{vvl})} 
     305\label{subsec:MBZ_dyn_spg_vvl} 
    309306 
    310307In the non-linear free surface formulation, the variations of volume are fully taken into account. 
    311 This option is presented in a report \citep{Levier2007} available on the NEMO web site. 
     308This option is presented in a report \citep{levier.treguier.ea_rpt07} available on the \NEMO\ web site. 
    312309The three time-stepping methods (explicit, split-explicit and filtered) are the same as in 
    313 \autoref{DYN_spg_linear} except that the ocean depth is now time-dependent. 
     310\autoref{?:DYN_spg_linear?} except that the ocean depth is now time-dependent. 
    314311In particular, this means that in filtered case, the matrix to be inverted has to be recomputed at each time-step. 
    315312 
    316 \biblio 
    317  
    318 \pindex 
     313\subinc{\input{../../global/epilogue}} 
    319314 
    320315\end{document} 
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