| 1 |
jmc |
1.1 |
|
| 2 |
jmc |
1.2 |
%\subsubsection{File {\it input/data.shap}} |
| 3 |
jmc |
1.1 |
%\label{www:tutorials} |
| 4 |
|
|
|
| 5 |
|
|
This file, reproduced completely below, specifies the parameters |
| 6 |
|
|
that the model uses for the Shapiro filter package (\cite{Shapiro_70}, |
| 7 |
|
|
section \ref{sect:shapiro-filter}). |
| 8 |
|
|
The parameters that are significant for this configuration are: |
| 9 |
|
|
|
| 10 |
|
|
\begin{itemize} |
| 11 |
|
|
|
| 12 |
|
|
\item Line PUT_LINE_NB:Shap_funct=, |
| 13 |
|
|
\begin{verbatim} |
| 14 |
|
|
Shap_funct=2, |
| 15 |
|
|
\end{verbatim} |
| 16 |
|
|
This line selects the shapiro filter function |
| 17 |
|
|
to use, here S2 in this experiment |
| 18 |
|
|
(see section \ref{sect:shapiro-filter}). |
| 19 |
|
|
|
| 20 |
|
|
\item Lines PUT_LINE_NB:nShapT= and PUT_LINE_NB:nShapUV=, |
| 21 |
|
|
\begin{verbatim} |
| 22 |
jmc |
1.4 |
nShapT=0, |
| 23 |
jmc |
1.1 |
nShapUV=4, |
| 24 |
|
|
\end{verbatim} |
| 25 |
|
|
Those lines select the order of the shapiro filter |
| 26 |
jmc |
1.2 |
for active tracer ($\theta$ and $q$) and momentum ($u,v$) respectively. |
| 27 |
jmc |
1.4 |
In this case, no filter is applied to active tracers. Regarding |
| 28 |
|
|
the momentum, this sets the integer parameter $n$ to 4, in the equations of |
| 29 |
jmc |
1.2 |
section \ref{sect:shapiro-filter}, which corresponds to a 8th order |
| 30 |
jmc |
1.1 |
filter. |
| 31 |
|
|
|
| 32 |
jmc |
1.4 |
\item Line PUT_LINE_NB:nShapUVPhys=, |
| 33 |
jmc |
1.1 |
\begin{verbatim} |
| 34 |
jmc |
1.4 |
nShapUVPhys=4, |
| 35 |
jmc |
1.1 |
\end{verbatim} |
| 36 |
jmc |
1.4 |
This line selects the order of the physical space filter |
| 37 |
jmc |
1.1 |
(filter function S2g, in section \ref{sect:shapiro-filter}) |
| 38 |
jmc |
1.4 |
that applies to $u,v$. |
| 39 |
|
|
The difference {\it nShapUV - nShapUVPhys} |
| 40 |
|
|
corresponds to the order of the computational filter |
| 41 |
jmc |
1.1 |
(filter function S2c, in section \ref{sect:shapiro-filter}). |
| 42 |
|
|
|
| 43 |
jmc |
1.4 |
\item Lines PUT_LINE_NB:#Shap_Trtau= and PUT_LINE_NB:#Shap_uvtau=, |
| 44 |
jmc |
1.1 |
\begin{verbatim} |
| 45 |
jmc |
1.4 |
#Shap_Trtau=5400., |
| 46 |
|
|
#Shap_uvtau=1800., |
| 47 |
jmc |
1.1 |
\end{verbatim} |
| 48 |
jmc |
1.4 |
Those commented lines would have set the time scale of the filter (in seconds), |
| 49 |
jmc |
1.1 |
for $\theta$ and $q$ and for $u$ and $v$ respectively, |
| 50 |
|
|
to 5400 s (90 min) and 1800 s (30 min) respectively. |
| 51 |
jmc |
1.4 |
Without explicitly setting those timescales, the default is used |
| 52 |
|
|
which corresponds to the model time-step. |
| 53 |
|
|
%Note that a shorter time scale means a stronger filter, and |
| 54 |
|
|
%that the time scale cannot be smaller than the time-step $\Delta t$ |
| 55 |
|
|
%of the model. |
| 56 |
jmc |
1.1 |
|
| 57 |
|
|
\end{itemize} |
| 58 |
|
|
|
| 59 |
|
|
The entire file {\it input/data.shap} is reproduced here below: |
| 60 |
|
|
|
| 61 |
jmc |
1.3 |
\begin{small} |
| 62 |
jmc |
1.5 |
\input{s_examples/held_suarez_cs/input/data.shap} |
| 63 |
jmc |
1.3 |
\end{small} |