/[MITgcm]/manual/s_phys_pkgs/text/rbcs.tex
ViewVC logotype

Diff of /manual/s_phys_pkgs/text/rbcs.tex

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph | View Patch Patch

revision 1.1 by stephd, Thu Jan 17 22:17:17 2008 UTC revision 1.5 by jahn, Tue Mar 4 20:20:48 2014 UTC
# Line 30  each of these Line 30  each of these
30  can be relaxed or not and can have its own timescale  can be relaxed or not and can have its own timescale
31  $\tau_T$. These are set in data.rbcs (see below).  $\tau_T$. These are set in data.rbcs (see below).
32    
33    
34  \subsubsection {Key subroutines and parameters}  \subsubsection {Key subroutines and parameters}
35    
36  The only change need in the code might be in {RBCS.H}, for  The only compile-time parameter you are likely to have to change is in {RBCS.h},
37  PARAMETER(maskLEN = 3 ), if you need more than 3  the number of masks, PARAMETER(maskLEN = 3 ), see below.
 masks (see below).  
38    
39  \vspace{.5cm}  The runtime parameters are set in {\it data.rbcs}:
40    
41    \vspace{.5cm}
42  \noindent  \noindent
 There are runtime parameters  
 set in {\it data.rbcs}:\\  
 These runtime options include\\  
43  Set in {RBCS\_PARM01}:\\  Set in {RBCS\_PARM01}:\\
44  $\bullet$ Parameters to set the timing for periodic fields to  $\bullet$ {\bf rbcsForcingPeriod}: time interval between forcing fields
45  relax to are to  (in seconds), zero means constant-in-time forcing.\\
46  be loaded are: {\it rbcs\_ForcingPeriod}, {\it rbcs\_ForcingCycle}.  $\bullet$ {\bf rbcsForcingCycle}: repeat cycle of forcing fields (in seconds),
47  The former is how often to load, the latter is how often to cycle  zero means non-cyclic forcing.\\
48  through those fields (eg. period couple be monthly and cycle one year).  $\bullet$  {\bf rbcsForcingOffset}: time offset of forcing fields
49  rbcs\_ForcingCycle=0 meaning no periodic forcing, and the relax field  (in seconds, default 0); this is relative to time averages starting at
50  is only read in at the beginning of the run and kept constant  $t=0$, i.e., the first forcing record/file is placed at
51  the rest of the run. Default is 0.  ${\rm rbcsForcingOffset+rbcsForcingPeriod}/2$; see below for examples.\\
52  \\  $\bullet$  {\bf rbcsSingleTimeFiles}: true or false (default false),
53  $\bullet$  {\bf rbcsIniter}: if you want to offset rbcs forcing  if true, forcing fields are given 1 file per rbcsForcingPeriod.\\
54  timing. Default is nIter0.\\  $\bullet$  {\bf deltaTrbcs}: time step used to compute the iteration numbers
55    for rbcsSingleTimeFiles=T.\\
56    $\bullet$  {\bf rbcsIter0}: shift in iteration numbers used to label files if
57    rbcsSingleTimeFiles=T (default 0, see below for examples).\\
58  $\bullet$  {\bf useRBCtemp}: true or false (default false)\\  $\bullet$  {\bf useRBCtemp}: true or false (default false)\\
59  $\bullet$  {\bf useRBCsalt}: true or false (default false)\\  $\bullet$  {\bf useRBCsalt}: true or false (default false)\\
60  $\bullet$  {\bf useRBCptracers}: true or false (default false), must be using  $\bullet$  {\bf useRBCptracers}: true or false (default false), must be using
# Line 61  ptracers to set true\\ Line 62  ptracers to set true\\
62  $\bullet$  {\bf tauRelaxT}: timescale in seconds of relaxing  $\bullet$  {\bf tauRelaxT}: timescale in seconds of relaxing
63  in temperature ($\tau_T$ in equation above).  in temperature ($\tau_T$ in equation above).
64  Where mask is 1, relax rate will be  Where mask is 1, relax rate will be
65  1/tauRelaxT. Default is 1.  1/tauRelaxT. Default is 1.\\
66  $\bullet$  {\bf tauRelaxS}: same for salinity.  $\bullet$  {\bf tauRelaxS}: same for salinity.\\
67  $\bullet$  {\bf relaxMaskFile(irbc)}: filename of 3-D file  $\bullet$  {\bf relaxMaskFile(irbc)}: filename of 3-D file
68  with mask ($M_{rbc}$ in equation above.  with mask ($M_{rbc}$ in equation above.
69  Need a file for each irbc. 1=temperature,  Need a file for each irbc. 1=temperature,
# Line 70  Need a file for each irbc. 1=temperature Line 71  Need a file for each irbc. 1=temperature
71  end (see maskLEN) are less than the number tracers, then  end (see maskLEN) are less than the number tracers, then
72  relaxMaskFile(maskLEN) is used for all remaining ptracers.\\  relaxMaskFile(maskLEN) is used for all remaining ptracers.\\
73  $\bullet$  {\bf relaxTFile}: name of file where temperatures  $\bullet$  {\bf relaxTFile}: name of file where temperatures
74  that need to be realxed to ($T_{rbc}$ in equation above)  that need to be relaxed to ($T_{rbc}$ in equation above)
75  are stored. Need 3-D fields to  are stored.  The file must contain 3-D records to match the model domain.
76  match model domain, and as many entries as given by  If rbcsSingleTimeFiles=F, it must have one record for each forcing period.
77  rbcsForcingPeriod and rbcsForcingCycle.\\  If T, there must be a separate file for each period and a 10-digit iteration
78    number is appended to the file name (see Table~\ref{tab:pkg:rbcs:timing}
79    and examples below).\\
80  $\bullet$  {\bf relaxSFile}: same for salinity.\\  $\bullet$  {\bf relaxSFile}: same for salinity.\\
81    
82  \vspace{.5cm}  \vspace{.5cm}
# Line 86  $\bullet$ {\bf relaxPtracerFile(iTrc)}: Line 89  $\bullet$ {\bf relaxPtracerFile(iTrc)}:
89  fields.\\  fields.\\
90    
91    
92    \subsubsection{Timing of relaxation forcing fields}
93    
94    For constant-in-time relaxation, set rbcsForcingPeriod=0.
95    For time-varying relaxation, Table~\ref{tab:pkg:rbcs:timing} illustrates the
96    relation between model time and forcing fields (either records in
97    one big file or, for rbcsSingleTimeFiles=T, individual files labeled with an
98    iteration number).  With rbcsSingleTimeFiles=T, this is the same as in the
99    offline package, except that the forcing offset is in seconds.
100    \newcommand{\dtr}{\Delta t_{\text{rbcs}}}%
101    \begin{table}
102        \centering
103        \begin{tabular}{|l|l|l|c|}
104          \hline
105          &
106          \multicolumn{2}{|c|}{rbcsSingleTimeFiles = T} &
107          F \\
108          &
109          \textbf{$c=0$} &
110          \textbf{$c\ne0$} &
111          \textbf{$c\ne0$}
112          \\ \hline
113          \textbf{model time} &
114          \textbf{file number} &
115          \textbf{file number} &
116          \textbf{record} \\
117          \hline \hline
118            $t_0 -     p/2$ & $i_0$            & $i_0 +   c/\dtr$ & $c/p$ \\ \hline
119            $t_0 +     p/2$ & $i_0 +   p/\dtr$ & $i_0 +   p/\dtr$ & $1$ \\ \hline
120            $t_0 + p + p/2$ & $i_0 + 2 p/\dtr$ & $i_0 + 2 p/\dtr$ & $2$ \\ \hline
121            \dots & \dots & \dots & \dots \\ \hline
122            $t_0 + c - p/2$ & \dots            & $i_0 +   c/\dtr$ & $c/p$ \\ \hline
123            \dots & \dots & \dots & \dots \\ \hline
124        \end{tabular}
125        \qquad
126        \begin{tabular}{c@{${}={}$}l}
127            \multicolumn{2}{l}{} \\[4ex]
128            \multicolumn{2}{l}{where} \\[1ex]
129            $p$    & rbcsForcingPeriod \\
130            $c$    & rbcsForcingCycle \\
131            $t_0$  & rbcsForcingOffset \\
132            $i_0$  & rbcsIter0 \\
133            $\dtr$ & deltaTrbcs \\
134        \end{tabular}\\[3ex]
135        \caption{Timing of relaxation forcing fields.}
136        \label{tab:pkg:rbcs:timing}
137    \end{table}
138    
139    
140    \subsubsection{Example 1: forcing with time averages starting at $t=0$}
141    
142    \paragraph{Cyclic data in a single file.}  Set rbcsSingleTimeFiles=F and
143    rbcsForcingOffset=0, and the model will start by interpolating the last and first
144    records of rbcs data, placed at $-p/2$ and $p/2$, resp., as appropriate for fields
145    averaged over the time intervals $[-p, 0]$ and $[0, p]$.
146    
147    \paragraph{Non-cyclic data, multiple files.}  Set rbcsForcingCycle=0 and
148    rbcsSingleTimeFiles=T.  With rbcsForcingOffset=0, rbcsIter0=0 and
149    deltaTrbcs=rbcsForcingPeriod, the model would then start by interpolating data from
150    files relax*File.0000000000.data and relax*File.0000000001.data, \dots,
151    again placed at $-p/2$ and $p/2$.
152    
153    
154    \subsubsection{Example 2: forcing with snapshots starting at $t=0$}
155    
156    \paragraph{Cyclic data in a single file.}  Set rbcsSingleTimeFiles=F and
157    rbcsForcingOffset=$-p/2$, and the model will start forcing with the first
158    record at $t=0$.
159    
160    \paragraph{Non-cyclic data, multiple files.}  Set rbcsForcingCycle=0 and
161    rbcsSingleTimeFiles=T.  In this case, it is more natural to set
162    rbcsForcingOffset=$+p/2$.
163    With rbcsIter0=0 and deltaTrbcs=rbcsForcingPeriod, the model would then start
164    with data from files relax*File.0000000000.data at $t=0$.
165    It would then proceed to interpolate between this file and files
166    relax*File.0000000001.data at $t={}$rbcsForcingPeriod.
167    
168    
169  \subsubsection{Do's and Don'ts}  \subsubsection{Do's and Don'ts}
170    
171  \subsubsection{Reference Material}  \subsubsection{Reference Material}
# Line 93  fields.\\ Line 173  fields.\\
173  \subsubsection{Experiments and tutorials that use rbcs}  \subsubsection{Experiments and tutorials that use rbcs}
174  \label{sec:pkg:rbcs:experiments}  \label{sec:pkg:rbcs:experiments}
175    
176    In the directory \code{verifcation}, the following experiments use
177    \code{rbcs}:
178    \begin{itemize}
179    \item \code{exp4}: box with 4 open boundaries, simulating flow over a
180      Gaussian bump based on \citet{adcroft:97}.
181    \end{itemize}
182    
183    
184    
185  \end{itemize}  %%% \end{itemize}
186    
Legend:
Removed from v.1.1  
changed lines
  Added in v.1.5
  ViewVC Help
Powered by ViewVC 1.1.22