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Changeset 2955 – NEMO

Changeset 2955


Ignore:
Timestamp:
2011-10-18T18:05:09+02:00 (12 years ago)
Author:
cbricaud
Message:

Add documentation for Diagnostic Tidal Harmonic

Location:
branches/2011/dev_r2787_MERCATOR2_tidalharm/DOC/TexFiles
Files:
1 added
1 edited

Legend:

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  • branches/2011/dev_r2787_MERCATOR2_tidalharm/DOC/TexFiles/Chapters/Chap_DIA.tex

    r2541 r2955  
    685685 
    686686% ------------------------------------------------------------------------------------------------------------- 
     687%       Harmonic analysis of tidal constituents 
     688% ------------------------------------------------------------------------------------------------------------- 
     689\section{Harmonic analysis of tidal constituents (\key{diaharm}) } 
     690\label{DIA_diag_harm} 
     691 
     692A module is available to compute the amplitude and phase for tidal waves.  
     693This diagnostic is actived with \key{diaharm}. 
     694 
     695%------------------------------------------namdia_harm---------------------------------------------------- 
     696\namdisplay{namdia_harm} 
     697%---------------------------------------------------------------------------------------------------------- 
     698 
     699Concerning the on-line Harmonic analysis, some parameters are available in namelist: 
     700 
     701- \texttt{nit000\_han} is the first time step used for harmonic analysis 
     702 
     703- \texttt{nitend\_han} is the last time step used for harmonic analysis 
     704 
     705- \texttt{nstep\_han} is the time step frequency for harmonic analysis 
     706 
     707- \texttt{nb\_ana} is the number of harmonics to analyse 
     708 
     709- \texttt{tname} is an array with names of tidal constituents to analyse 
     710 
     711\texttt{nit000\_han} and \texttt{nitend\_han} must be between \texttt{nit000} and \texttt{nitend} of the simulation. 
     712The restart capability is not implemented. 
     713 
     714The Harmonic analysis solve this equation: 
     715\begin{equation} 
     716h_{i} - A_{0} + \sum^{nb\_ana}_{j=1}[A_{j}cos(\nu_{j}t_{j}-\phi_{j})] = e_{i} 
     717\end{equation} 
     718 
     719With $A_{j}$,$\nu_{j}$,$\phi_{j}$, the amplitude, frequency and phase for each wave and $e_{i}$ the error. 
     720$h_{i}$ is the sea level for the time $t_{i}$ and $A_{0}$ is the mean sea level. \\ 
     721We can rewrite this equation: 
     722\begin{equation} 
     723h_{i} - A_{0} + \sum^{nb\_ana}_{j=1}[C_{j}cos(\nu_{j}t_{j})+S_{j}sin(\nu_{j}t_{j})] = e_{i} 
     724\end{equation} 
     725with $A_{j}=\sqrt{C^{2}_{j}+S^{2}_{j}}$ et $\phi_{j}=arctan(S_{j}/C_{j})$. 
     726 
     727We obtain in output $C_{j}$ and $S_{j}$ for each tidal wave. 
     728 
     729% ------------------------------------------------------------------------------------------------------------- 
    687730%       Other Diagnostics 
    688731% ------------------------------------------------------------------------------------------------------------- 
     
    735778 
    736779 
    737  
    738780% ================================================================ 
    739781% Steric effect in sea surface height 
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