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Changeset 11831 for NEMO/branches/2019/dev_r11085_ASINTER-05_Brodeau_Advanced_Bulk/doc/latex/NEMO/subfiles/chap_misc.tex – NEMO

Ignore:
Timestamp:
2019-10-29T18:14:49+01:00 (4 years ago)
Author:
laurent
Message:

Update the branch to r11830 of the trunk!

Location:
NEMO/branches/2019/dev_r11085_ASINTER-05_Brodeau_Advanced_Bulk/doc
Files:
5 edited

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    r10601 r11831  
    22 
    33\begin{document} 
    4 % ================================================================ 
    5 % Chapter --- Miscellaneous Topics 
    6 % ================================================================ 
     4 
    75\chapter{Miscellaneous Topics} 
    86\label{chap:MISC} 
    97 
    10 \minitoc 
    11  
    12 \newpage 
    13  
    14 % ================================================================ 
    15 % Representation of Unresolved Straits 
    16 % ================================================================ 
     8\thispagestyle{plain} 
     9 
     10\chaptertoc 
     11 
     12\paragraph{Changes record} ~\\ 
     13 
     14{\footnotesize 
     15  \begin{tabularx}{\textwidth}{l||X|X} 
     16    Release & Author(s) & Modifications \\ 
     17    \hline 
     18    {\em   4.0} & {\em ...} & {\em ...} \\ 
     19    {\em   3.6} & {\em ...} & {\em ...} \\ 
     20    {\em   3.4} & {\em ...} & {\em ...} \\ 
     21    {\em <=3.4} & {\em ...} & {\em ...} 
     22  \end{tabularx} 
     23} 
     24 
     25\clearpage 
     26 
     27%% ================================================================================================= 
    1728\section{Representation of unresolved straits} 
    1829\label{sec:MISC_strait} 
     
    2738balance the net evaporation occurring over the Mediterranean region. 
    2839This problem occurs even in eddy permitting simulations. 
    29 For example, in ORCA 1/4\deg several straits of the Indonesian archipelago (Ombai, Lombok...) 
     40For example, in ORCA 1/4\deg\ several straits of the Indonesian archipelago (Ombai, Lombok...) 
    3041are much narrow than even a single ocean grid-point. 
    3142 
    32 We describe briefly here the three methods that can be used in \NEMO to handle such improperly resolved straits. 
    33 The first two consist of opening the strait by hand while ensuring that the mass exchanges through 
    34 the strait are not too large by either artificially reducing the surface of the strait grid-cells or, 
    35 locally increasing the lateral friction. 
    36 In the third one, the strait is closed but exchanges of mass, heat and salt across the land are allowed. 
    37 Note that such modifications are so specific to a given configuration that no attempt has been made to 
    38 set them in a generic way. 
    39 However, examples of how they can be set up is given in the ORCA 2\deg and 0.5\deg configurations. 
    40 For example, for details of implementation in ORCA2, search: \texttt{IF( cp\_cfg == "orca" .AND. jp\_cfg == 2 )} 
    41  
    42 % ------------------------------------------------------------------------------------------------------------- 
    43 %       Hand made geometry changes 
    44 % ------------------------------------------------------------------------------------------------------------- 
     43We describe briefly here the two methods that can be used in \NEMO\ to handle such 
     44improperly resolved straits. The methods consist of opening the strait while ensuring 
     45that the mass exchanges through the strait are not too large by either artificially 
     46reducing the cross-sectional area of the strait grid-cells or, locally increasing the 
     47lateral friction. 
     48 
     49%% ================================================================================================= 
    4550\subsection{Hand made geometry changes} 
    4651\label{subsec:MISC_strait_hand} 
    4752 
    48 $\bullet$ reduced scale factor in the cross-strait direction to a value in better agreement with 
    49 the true mean width of the strait (\autoref{fig:MISC_strait_hand}). 
    50 This technique is sometime called "partially open face" or "partially closed cells". 
    51 The key issue here is only to reduce the faces of $T$-cell 
    52 (\ie change the value of the horizontal scale factors at $u$- or $v$-point) but not the volume of the $T$-cell. 
    53 Indeed, reducing the volume of strait $T$-cell can easily produce a numerical instability at 
    54 that grid point that would require a reduction of the model time step. 
    55 The changes associated with strait management are done in \mdl{domhgr}, 
    56 just after the definition or reading of the horizontal scale factors.  
    57  
    58 $\bullet$ increase of the viscous boundary layer thickness by local increase of the fmask value at the coast 
    59 (\autoref{fig:MISC_strait_hand}). 
    60 This is done in \mdl{dommsk} together with the setting of the coastal value of fmask (see  \autoref{sec:LBC_coast}). 
    61  
    62 %>>>>>>>>>>>>>>>>>>>>>>>>>>>> 
     53The first method involves reducing the scale factor in the cross-strait direction to a 
     54value in better agreement with the true mean width of the strait 
     55(\autoref{fig:MISC_strait_hand}).  This technique is sometime called "partially open face" 
     56or "partially closed cells".  The key issue here is only to reduce the faces of $T$-cell 
     57(\ie\ change the value of the horizontal scale factors at $u$- or $v$-point) but not the 
     58volume of the $T$-cell.  Indeed, reducing the volume of strait $T$-cell can easily produce 
     59a numerical instability at that grid point which would require a reduction of the model 
     60time step.  Thus to instigate a local change in the width of a Strait requires two steps: 
     61 
     62\begin{itemize} 
     63 
     64\item Add \texttt{e1e2u} and \texttt{e1e2v} arrays to the \np{cn_domcfg}{cn\_domcfg} file. These 2D 
     65arrays should contain the products of the unaltered values of: $\texttt{e1u}*\texttt{e2u}$ 
     66and $\texttt{e1u}*\texttt{e2v}$ respectively. That is the original surface areas of $u$- 
     67and $v$- cells respectively.  These areas are usually defined by the corresponding product 
     68within the \NEMO\ code but the presence of \texttt{e1e2u} and \texttt{e1e2v} in the 
     69\np{cn_domcfg}{cn\_domcfg} file will suppress this calculation and use the supplied fields instead. 
     70If the model domain is provided by user-supplied code in \mdl{usrdef\_hgr}, then this 
     71routine should also return \texttt{e1e2u} and \texttt{e1e2v} and set the integer return 
     72argument \texttt{ie1e2u\_v} to a non-zero value. Values other than 0 for this argument 
     73will suppress the calculation of the areas. 
     74 
     75\item Change values of \texttt{e2u} or \texttt{e1v} (either in the \np{cn_domcfg}{cn\_domcfg} file or 
     76via code in  \mdl{usrdef\_hgr}), whereever a Strait reduction is required. The choice of 
     77whether to alter \texttt{e2u} or \texttt{e1v} depends. respectively,  on whether the 
     78Strait in question is North-South orientated (\eg\ Gibraltar) or East-West orientated (\eg 
     79Lombok). 
     80 
     81\end{itemize} 
     82 
     83The second method is to increase the viscous boundary layer thickness by a local increase 
     84of the fmask value at the coast. This method can also be effective in wider passages.  The 
     85concept is illustarted in the second part of  \autoref{fig:MISC_strait_hand} and changes 
     86to specific locations can be coded in \mdl{usrdef\_fmask}. The \forcode{usr_def_fmask} 
     87routine is always called after \texttt{fmask} has been defined according to the choice of 
     88lateral boundary condition as discussed in \autoref{sec:LBC_coast}. The default version of 
     89\mdl{usrdef\_fmask} contains settings specific to ORCA2 and ORCA1 configurations. These are 
     90meant as examples only; it is up to the user to verify settings and provide alternatives 
     91for their own configurations. The default \forcode{usr_def_fmask} makes no changes to 
     92\texttt{fmask} for any other configuration. 
     93 
    6394\begin{figure}[!tbp] 
    64   \begin{center} 
    65     \includegraphics[width=0.80\textwidth]{Fig_Gibraltar} 
    66     \includegraphics[width=0.80\textwidth]{Fig_Gibraltar2} 
    67     \caption{ 
    68       \protect\label{fig:MISC_strait_hand} 
    69       Example of the Gibraltar strait defined in a $1^{\circ} \times 1^{\circ}$ mesh. 
    70       \textit{Top}: using partially open cells. 
    71       The meridional scale factor at $v$-point is reduced on both sides of the strait to account for 
    72       the real width of the strait (about 20 km). 
    73       Note that the scale factors of the strait $T$-point remains unchanged. 
    74       \textit{Bottom}: using viscous boundary layers. 
    75       The four fmask parameters along the strait coastlines are set to a value larger than 4, 
    76       \ie "strong" no-slip case (see \autoref{fig:LBC_shlat}) creating a large viscous boundary layer that 
    77       allows a reduced transport through the strait. 
    78     } 
    79   \end{center} 
     95  \centering 
     96  \includegraphics[width=0.66\textwidth]{MISC_Gibraltar} 
     97  \includegraphics[width=0.66\textwidth]{MISC_Gibraltar2} 
     98  \caption[Two methods to defined the Gibraltar strait]{ 
     99    Example of the Gibraltar strait defined in a 1\deg\ $\times$ 1\deg\ mesh. 
     100    \textit{Top}: using partially open cells. 
     101    The meridional scale factor at $v$-point is reduced on both sides of the strait to 
     102    account for the real width of the strait (about 20 km). 
     103    Note that the scale factors of the strait $T$-point remains unchanged. 
     104    \textit{Bottom}: using viscous boundary layers. 
     105    The four fmask parameters along the strait coastlines are set to a value larger than 4, 
     106    \ie\ "strong" no-slip case (see \autoref{fig:LBC_shlat}) creating a large viscous boundary layer 
     107    that allows a reduced transport through the strait.} 
     108  \label{fig:MISC_strait_hand} 
    80109\end{figure} 
    81 %>>>>>>>>>>>>>>>>>>>>>>>>>>>> 
    82  
    83 %>>>>>>>>>>>>>>>>>>>>>>>>>>>> 
     110 
    84111\begin{figure}[!tbp] 
    85   \begin{center} 
    86     \includegraphics[width=1.0\textwidth]{Fig_closea_mask_example} 
    87     \caption{ 
    88       \protect\label{fig:closea_mask_example} 
    89       Example of mask fields for the closea module. \textit{Left}: a 
    90       closea\_mask field; \textit{Right}: a closea\_mask\_rnf 
    91       field. In this example, if ln\_closea is set to .true., the mean 
    92       freshwater flux over each of the American Great Lakes will be 
    93       set to zero, and the total residual for all the lakes, if 
    94       negative, will be put into the St Laurence Seaway in the area 
    95       shown.  
    96     } 
    97   \end{center} 
     112  \centering 
     113  \includegraphics[width=0.66\textwidth]{MISC_closea_mask_example} 
     114  \caption[Mask fields for the \protect\mdl{closea} module]{ 
     115    Example of mask fields for the \protect\mdl{closea} module. 
     116    \textit{Left}: a closea\_mask field; 
     117    \textit{Right}: a closea\_mask\_rnf field. 
     118    In this example, if \protect\np{ln_closea}{ln\_closea} is set to \forcode{.true.}, 
     119    the mean freshwater flux over each of the American Great Lakes will be set to zero, 
     120    and the total residual for all the lakes, if negative, will be put into 
     121    the St Laurence Seaway in the area shown.} 
     122  \label{fig:MISC_closea_mask_example} 
    98123\end{figure} 
    99 %>>>>>>>>>>>>>>>>>>>>>>>>>>>> 
    100  
    101 % ================================================================ 
    102 % Closed seas 
    103 % ================================================================ 
    104 \section{Closed seas (\protect\mdl{closea})} 
     124 
     125%% ================================================================================================= 
     126\section[Closed seas (\textit{closea.F90})]{Closed seas (\protect\mdl{closea})} 
    105127\label{sec:MISC_closea} 
    106128 
     
    116138to zero and put the residual flux into the ocean. 
    117139 
    118 Prior to NEMO 4 the locations of inland seas and lakes was set via 
    119 hardcoded indices for various ORCA configurations. From NEMO 4 onwards 
     140Prior to \NEMO\ 4 the locations of inland seas and lakes was set via 
     141hardcoded indices for various ORCA configurations. From \NEMO\ 4 onwards 
    120142the inland seas and lakes are defined using mask fields in the 
    121143domain configuration file. The options are as follows. 
    122144 
    123145\begin{enumerate} 
    124 \item{{\bf No ``closea\_mask'' field is included in domain configuration 
     146\item {{\bfseries No ``closea\_mask'' field is included in domain configuration 
    125147  file.} In this case the closea module does nothing.} 
    126148 
    127 \item{{\bf A field called closea\_mask is included in the domain 
     149\item {{\bfseries A field called closea\_mask is included in the domain 
    128150configuration file and ln\_closea=.false. in namelist namcfg.} In this 
    129151case the inland seas defined by the closea\_mask field are filled in 
     
    131153closea\_mask that is nonzero is set to be a land point.} 
    132154 
    133 \item{{\bf A field called closea\_mask is included in the domain 
     155\item {{\bfseries A field called closea\_mask is included in the domain 
    134156configuration file and ln\_closea=.true. in namelist namcfg.} Each 
    135157inland sea or group of inland seas is set to a positive integer value 
    136 in the closea\_mask field (see Figure \ref{fig:closea_mask_example} 
     158in the closea\_mask field (see \autoref{fig:MISC_closea_mask_example} 
    137159for an example). The net surface flux over each inland sea or group of 
    138160inland seas is set to zero each timestep and the residual flux is 
     
    140162closea\_mask is zero).} 
    141163 
    142 \item{{\bf Fields called closea\_mask and closea\_mask\_rnf are 
     164\item {{\bfseries Fields called closea\_mask and closea\_mask\_rnf are 
    143165included in the domain configuration file and ln\_closea=.true. in 
    144166namelist namcfg.} This option works as for option 3, except that if 
     
    149171by the closea\_mask\_rnf field. Each mapping is defined by a positive 
    150172integer value for the inland sea(s) and the corresponding runoff 
    151 points. An example is given in Figure 
    152 \ref{fig:closea_mask_example}. If no mapping is provided for a 
     173points. An example is given in 
     174\autoref{fig:MISC_closea_mask_example}. If no mapping is provided for a 
    153175particular inland sea then the residual is spread over the global 
    154176ocean.} 
    155177 
    156 \item{{\bf Fields called closea\_mask and closea\_mask\_emp are 
     178\item {{\bfseries Fields called closea\_mask and closea\_mask\_emp are 
    157179included in the domain configuration file and ln\_closea=.true. in 
    158180namelist namcfg.} This option works the same as option 4 except that 
     
    164186 
    165187There is a python routine to create the closea\_mask fields and append 
    166 them to the domain configuration file in the utils/tools/DOMAINcfg directory.  
    167  
    168 % ================================================================ 
    169 % Sub-Domain Functionality  
    170 % ================================================================ 
     188them to the domain configuration file in the utils/tools/DOMAINcfg directory. 
     189 
     190%% ================================================================================================= 
    171191\section{Sub-domain functionality} 
    172192\label{sec:MISC_zoom} 
    173193 
     194%% ================================================================================================= 
    174195\subsection{Simple subsetting of input files via NetCDF attributes} 
    175196 
    176 The extended grids for use with the under-shelf ice cavities will result in redundant rows around Antarctica if 
    177 the ice cavities are not active. 
    178 A simple mechanism for subsetting input files associated with the extended domains has been implemented to 
    179 avoid the need to maintain different sets of input fields for use with or without active ice cavities. 
    180 The existing 'zoom' options are overly complex for this task and marked for deletion anyway. 
    181 This alternative subsetting operates for the j-direction only and works by optionally looking for and 
    182 using a global file attribute (named: \np{open\_ocean\_jstart}) to determine the starting j-row for input. 
    183 The use of this option is best explained with an example: 
    184 consider an ORCA1 configuration using the extended grid bathymetry and coordinate files: 
    185 \vspace{-10pt} 
    186 \ifile{eORCA1\_bathymetry\_v2} 
    187 \ifile{eORCA1\_coordinates} 
    188 \noindent These files define a horizontal domain of 362x332. 
    189 Assuming the first row with open ocean wet points in the non-isf bathymetry for this set is row 42 
    190 (\fortran indexing) then the formally correct setting for \np{open\_ocean\_jstart} is 41. 
    191 Using this value as the first row to be read will result in a 362x292 domain which is the same size as 
    192 the original ORCA1 domain. 
    193 Thus the extended coordinates and bathymetry files can be used with all the original input files for ORCA1 if 
    194 the ice cavities are not active (\np{ln\_isfcav = .false.}). 
    195 Full instructions for achieving this are: 
    196  
    197 \noindent Add the new attribute to any input files requiring a j-row offset, i.e: 
    198 \vspace{-10pt} 
     197The extended grids for use with the under-shelf ice cavities will result in redundant rows 
     198around Antarctica if the ice cavities are not active.  A simple mechanism for subsetting 
     199input files associated with the extended domains has been implemented to avoid the need to 
     200maintain different sets of input fields for use with or without active ice cavities.  This 
     201subsetting operates for the j-direction only and works by optionally looking for and using 
     202a global file attribute (named: \np{open_ocean_jstart}{open\_ocean\_jstart}) to determine the starting j-row 
     203for input.  The use of this option is best explained with an example: 
     204\medskip 
     205 
     206\noindent Consider an ORCA1 
     207configuration using the extended grid domain configuration file: \ifile{eORCA1\_domcfg.nc} 
     208This file define a horizontal domain of 362x332.  The first row with 
     209open ocean wet points in the non-isf bathymetry for this set is row 42 (\fortran\ indexing) 
     210then the formally correct setting for \np{open_ocean_jstart}{open\_ocean\_jstart} is 41.  Using this value as 
     211the first row to be read will result in a 362x292 domain which is the same size as the 
     212original ORCA1 domain.  Thus the extended domain configuration file can be used with all 
     213the original input files for ORCA1 if the ice cavities are not active (\np{ln\_isfcav = 
     214.false.}).  Full instructions for achieving this are: 
     215 
     216\begin{itemize} 
     217\item Add the new attribute to any input files requiring a j-row offset, i.e: 
    199218\begin{cmds} 
    200 ncatted  -a open_ocean_jstart,global,a,d,41 eORCA1_coordinates.nc  
    201 ncatted  -a open_ocean_jstart,global,a,d,41 eORCA1_bathymetry_v2.nc 
     219ncatted  -a open_ocean_jstart,global,a,d,41 eORCA1_domcfg.nc 
    202220\end{cmds} 
    203   
    204 \noindent Add the logical switch to \ngn{namcfg} in the configuration namelist and set true: 
    205 %--------------------------------------------namcfg-------------------------------------------------------- 
    206  
    207 \nlst{namcfg} 
    208 %-------------------------------------------------------------------------------------------------------------- 
    209  
    210 \noindent Note the j-size of the global domain is the (extended j-size minus \np{open\_ocean\_jstart} + 1 ) and 
    211 this must match the size of all datasets other than bathymetry and coordinates currently. 
    212 However the option can be extended to any global, 2D and 3D, netcdf, input field by adding the: 
    213 \vspace{-10pt} 
     221 
     222\item Add the logical switch \np{ln_use_jattr}{ln\_use\_jattr} to \nam{cfg}{cfg} in the configuration 
     223namelist (if it is not already there) and set \forcode{.true.} 
     224\end{itemize} 
     225 
     226\noindent Note that with this option, the j-size of the global domain is (extended 
     227j-size minus \np{open_ocean_jstart}{open\_ocean\_jstart} + 1 ) and this must match the \texttt{jpjglo} value 
     228for the configuration. This means an alternative version of \ifile{eORCA1\_domcfg.nc} must 
     229be created for when \np{ln_use_jattr}{ln\_use\_jattr} is active. The \texttt{ncap2} tool provides a 
     230convenient way of achieving this: 
     231 
     232\begin{cmds} 
     233ncap2 -s 'jpjglo=292' eORCA1_domcfg.nc nORCA1_domcfg.nc 
     234\end{cmds} 
     235 
     236The domain configuration file is unique in this respect since it also contains the value of \jp{jpjglo} 
     237that is read and used by the model. 
     238Any other global, 2D and 3D, netcdf, input field can be prepared for use in a reduced domain by adding the 
     239\texttt{open\_ocean\_jstart} attribute to the file's global attributes. 
     240In particular this is true for any field that is read by \NEMO\ using the following optional argument to 
     241the appropriate call to \np{iom_get}{iom\_get}. 
     242 
    214243\begin{forlines} 
    215244lrowattr=ln_use_jattr 
    216245\end{forlines} 
    217 optional argument to the appropriate \np{iom\_get} call and the \np{open\_ocean\_jstart} attribute to 
    218 the corresponding input files. 
    219 It remains the users responsibility to set \np{jpjdta} and \np{jpjglo} values in 
    220 the \np{namelist\_cfg} file according to their needs. 
    221  
    222 %>>>>>>>>>>>>>>>>>>>>>>>>>>>> 
    223 \begin{figure}[!ht] 
    224   \begin{center} 
    225     \includegraphics[width=0.90\textwidth]{Fig_LBC_zoom} 
    226     \caption{ 
    227       \protect\label{fig:LBC_zoom} 
    228       Position of a model domain compared to the data input domain when the zoom functionality is used. 
    229     } 
    230   \end{center} 
    231 \end{figure} 
    232 %>>>>>>>>>>>>>>>>>>>>>>>>>>>> 
    233  
    234  
    235 % ================================================================ 
    236 % Accuracy and Reproducibility 
    237 % ================================================================ 
    238 \section{Accuracy and reproducibility (\protect\mdl{lib\_fortran})} 
     246 
     247Currently, only the domain configuration variables make use of this optional argument so 
     248this facility is of little practical use except for tests where no other external input 
     249files are needed or you wish to use an extended domain configuration with inputs from 
     250earlier, non-extended configurations. Alternatively, it should be possible to exclude 
     251empty rows for extended domain, forced ocean runs using interpolation on the fly, by 
     252adding the optional argument to \texttt{iom\_get} calls for the weights and initial 
     253conditions. Experimenting with this remains an exercise for the user. 
     254 
     255%% ================================================================================================= 
     256\section[Accuracy and reproducibility (\textit{lib\_fortran.F90})]{Accuracy and reproducibility (\protect\mdl{lib\_fortran})} 
    239257\label{sec:MISC_fortran} 
    240258 
    241 \subsection{Issues with intrinsinc SIGN function (\protect\key{nosignedzero})} 
     259%% ================================================================================================= 
     260\subsection[Issues with intrinsinc SIGN function (\texttt{\textbf{key\_nosignedzero}})]{Issues with intrinsinc SIGN function (\protect\key{nosignedzero})} 
    242261\label{subsec:MISC_sign} 
    243262 
    244 The SIGN(A, B) is the \fortran intrinsic function delivers the magnitude of A with the sign of B. 
     263The SIGN(A, B) is the \fortran\ intrinsic function delivers the magnitude of A with the sign of B. 
    245264For example, SIGN(-3.0,2.0) has the value 3.0. 
    246265The problematic case is when the second argument is zero, because, on platforms that support IEEE arithmetic, 
     
    254273and the processor is capable of distinguishing between positive and negative zero, 
    255274and B is negative real zero. 
    256 Then SIGN delivers a negative result where, under \fninety rules, it used to return a positive result. 
     275Then SIGN delivers a negative result where, under \fninety\ rules, it used to return a positive result. 
    257276This change may be especially sensitive for the ice model, 
    258277so we overwrite the intrinsinc function with our own function simply performing :   \\ 
     
    264283some computers/compilers. 
    265284 
    266  
     285%% ================================================================================================= 
    267286\subsection{MPP reproducibility} 
    268287\label{subsec:MISC_glosum} 
    269288 
    270289The numerical reproducibility of simulations on distributed memory parallel computers is a critical issue. 
    271 In particular, within NEMO global summation of distributed arrays is most susceptible to rounding errors, 
     290In particular, within \NEMO\ global summation of distributed arrays is most susceptible to rounding errors, 
    272291and their propagation and accumulation cause uncertainty in final simulation reproducibility on 
    273292different numbers of processors. 
    274 To avoid so, based on \citet{He_Ding_JSC01} review of different technics, 
     293To avoid so, based on \citet{he.ding_JS01} review of different technics, 
    275294we use a so called self-compensated summation method. 
    276 The idea is to estimate the roundoff error, store it in a buffer, and then add it back in the next addition.  
     295The idea is to estimate the roundoff error, store it in a buffer, and then add it back in the next addition. 
    277296 
    278297Suppose we need to calculate $b = a_1 + a_2 + a_3$. 
     
    292311The self-compensated summation method should be used in all summation in i- and/or j-direction. 
    293312See \mdl{closea} module for an example. 
    294 Note also that this implementation may be sensitive to the optimization level.  
    295  
     313Note also that this implementation may be sensitive to the optimization level. 
     314 
     315%% ================================================================================================= 
    296316\subsection{MPP scalability} 
    297317\label{subsec:MISC_mppsca} 
     
    313333be set at all the locations actually required by each individual for the fold operation. 
    314334This alternative method should give identical results to the default \textsc{ALLGATHER} method and 
    315 is recommended for large values of \np{jpni}. 
    316 The new method is activated by setting \np{ln\_nnogather} to be true ({\bf nammpp}). 
     335is recommended for large values of \np{jpni}{jpni}. 
     336The new method is activated by setting \np{ln_nnogather}{ln\_nnogather} to be true (\nam{mpp}{mpp}). 
    317337The reproducibility of results using the two methods should be confirmed for each new, 
    318338non-reference configuration. 
    319339 
    320 % ================================================================ 
    321 % Model optimisation, Control Print and Benchmark 
    322 % ================================================================ 
     340%% ================================================================================================= 
    323341\section{Model optimisation, control print and benchmark} 
    324342\label{sec:MISC_opt} 
    325 %--------------------------------------------namctl------------------------------------------------------- 
    326  
    327 \nlst{namctl}  
    328 %-------------------------------------------------------------------------------------------------------------- 
    329  
    330 Options are defined through the  \ngn{namctl} namelist variables. 
    331  
     343 
     344\begin{listing} 
     345  \nlst{namctl} 
     346  \caption{\forcode{&namctl}} 
     347  \label{lst:namctl} 
     348\end{listing} 
     349 
     350Options are defined through the  \nam{ctl}{ctl} namelist variables. 
     351 
     352%% ================================================================================================= 
    332353\subsection{Vector optimisation} 
    333354 
     
    335356This is very a very efficient way to increase the length of vector calculations and thus 
    336357to speed up the model on vector computers. 
    337   
     358 
    338359% Add here also one word on NPROMA technique that has been found useless, since compiler have made significant progress during the last decade. 
    339   
     360 
    340361% Add also one word on NEC specific optimisation (Novercheck option for example) 
    341   
     362 
     363%% ================================================================================================= 
    342364\subsection{Control print} 
    343365 
    344 The \np{ln\_ctl} switch was originally used as a debugging option in two modes: 
     366The \np{ln_ctl}{ln\_ctl} switch was originally used as a debugging option in two modes: 
    345367 
    346368\begin{enumerate} 
    347 \item{\np{ln\_ctl}: compute and print the trends averaged over the interior domain in all TRA, DYN, LDF and 
     369\item {\np{ln_ctl}{ln\_ctl}: compute and print the trends averaged over the interior domain in all TRA, DYN, LDF and 
    348370ZDF modules. 
    349371This option is very helpful when diagnosing the origin of an undesired change in model results. } 
    350372 
    351 \item{also \np{ln\_ctl} but using the nictl and njctl namelist parameters to check the source of differences between 
     373\item {also \np{ln_ctl}{ln\_ctl} but using the nictl and njctl namelist parameters to check the source of differences between 
    352374mono and multi processor runs.} 
    353375\end{enumerate} 
    354376 
    355377However, in recent versions it has also been used to force all processors to assume the 
    356 reporting role. Thus when \np{ln\_ctl} is true all processors produce their own versions 
     378reporting role. Thus when \np{ln_ctl}{ln\_ctl} is true all processors produce their own versions 
    357379of files such as: ocean.output, layout.dat, etc.  All such files, beyond the the normal 
    358380reporting processor (narea == 1), are named with a \_XXXX extension to their name, where 
     
    360382such as run.stat (and its netCDF counterpart: run.stat.nc) and tracer.stat contain global 
    361383information and are only ever produced by the reporting master (narea == 1). For version 
    362 4.0 a start has been made to return \np{ln\_ctl} to its original function by introducing 
     3844.0 a start has been made to return \np{ln_ctl}{ln\_ctl} to its original function by introducing 
    363385a new control structure which allows finer control over which files are produced. This 
    364386feature is still evolving but it does already allow the user to: select individually the 
     
    386408at a suitably long interval. For example: 
    387409 
    388 \begin{verbatim}      
     410\begin{verbatim} 
    389411       sn_cfctl%ptimincr  = 25 
    390412\end{verbatim} 
    391413 
    392 will carry out the global communications and write the information every 25 timesteps. This  
     414will carry out the global communications and write the information every 25 timesteps. This 
    393415increment also applies to the time.step file which is otherwise updated every timestep. 
    394416 
    395 % ================================================================ 
    396 \biblio 
    397  
    398 \pindex 
     417\subinc{\input{../../global/epilogue}} 
    399418 
    400419\end{document} 
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