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Changeset 11123 for NEMO/trunk/doc/latex/NEMO/subfiles/chap_time_domain.tex – NEMO

Ignore:
Timestamp:
2019-06-17T14:22:27+02:00 (5 years ago)
Author:
nicolasmartin
Message:

Modification of LaTeX subfiles accordingly to new citations keys

Location:
NEMO/trunk/doc/latex/NEMO/subfiles
Files:
2 edited

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  • NEMO/trunk/doc/latex/NEMO/subfiles/chap_time_domain.tex

    r10501 r11123  
    6464 
    6565The time stepping used for processes other than diffusion is the well-known leapfrog scheme 
    66 \citep{Mesinger_Arakawa_Bk76}. 
     66\citep{mesinger.arakawa_bk76}. 
    6767This scheme is widely used for advection processes in low-viscosity fluids. 
    6868It is a time centred scheme, \ie the RHS in \autoref{eq:STP} is evaluated at time step $t$, the now time step. 
     
    8080To prevent it, the leapfrog scheme is often used in association with a Robert-Asselin time filter 
    8181(hereafter the LF-RA scheme). 
    82 This filter, first designed by \citet{Robert_JMSJ66} and more comprehensively studied by \citet{Asselin_MWR72}, 
     82This filter, first designed by \citet{robert_JMSJ66} and more comprehensively studied by \citet{asselin_MWR72}, 
    8383is a kind of laplacian diffusion in time that mixes odd and even time steps: 
    8484\begin{equation} 
     
    8989$\gamma$ is initialized as \np{rn\_atfp} (namelist parameter). 
    9090Its default value is \np{rn\_atfp}~\forcode{= 10.e-3} (see \autoref{sec:STP_mLF}), 
    91 causing only a weak dissipation of high frequency motions (\citep{Farge1987}). 
     91causing only a weak dissipation of high frequency motions (\citep{farge-coulombier_phd87}). 
    9292The addition of a time filter degrades the accuracy of the calculation from second to first order. 
    9393However, the second order truncation error is proportional to $\gamma$, which is small compared to 1. 
     
    115115 
    116116This is diffusive in time and conditionally stable. 
    117 The conditions for stability of second and fourth order horizontal diffusion schemes are \citep{Griffies_Bk04}: 
     117The conditions for stability of second and fourth order horizontal diffusion schemes are \citep{griffies_bk04}: 
    118118\begin{equation} 
    119119  \label{eq:STP_euler_stability} 
     
    183183$c(k)$ and $d(k)$ are positive and the diagonal term is greater than the sum of the two extra-diagonal terms, 
    184184therefore a special adaptation of the Gauss elimination procedure is used to find the solution 
    185 (see for example \citet{Richtmyer1967}). 
     185(see for example \citet{richtmyer.morton_bk67}). 
    186186 
    187187% ------------------------------------------------------------------------------------------------------------- 
     
    200200    \caption{ 
    201201      \protect\label{fig:TimeStep_flowchart} 
    202       Sketch of the leapfrog time stepping sequence in \NEMO from \citet{Leclair_Madec_OM09}. 
     202      Sketch of the leapfrog time stepping sequence in \NEMO from \citet{leclair.madec_OM09}. 
    203203      The use of a semi -implicit computation of the hydrostatic pressure gradient requires the tracer equation to 
    204204      be stepped forward prior to the momentum equation. 
     
    219219\label{sec:STP_mLF} 
    220220 
    221 Significant changes have been introduced by \cite{Leclair_Madec_OM09} in the LF-RA scheme in order to 
     221Significant changes have been introduced by \cite{leclair.madec_OM09} in the LF-RA scheme in order to 
    222222ensure tracer conservation and to allow the use of a much smaller value of the Asselin filter parameter. 
    223223The modifications affect both the forcing and filtering treatments in the LF-RA scheme. 
     
    237237The change in the forcing formulation given by \autoref{eq:STP_forcing} (see \autoref{fig:MLF_forcing}) 
    238238has a significant effect: 
    239 the forcing term no longer excites the divergence of odd and even time steps \citep{Leclair_Madec_OM09}. 
     239the forcing term no longer excites the divergence of odd and even time steps \citep{leclair.madec_OM09}. 
    240240% forcing seen by the model.... 
    241241This property improves the LF-RA scheme in two respects. 
     
    245245(last term in \autoref{eq:STP_RA} compared to \autoref{eq:STP_asselin}). 
    246246Since the filtering of the forcing was the source of non-conservation in the classical LF-RA scheme, 
    247 the modified formulation becomes conservative \citep{Leclair_Madec_OM09}. 
     247the modified formulation becomes conservative \citep{leclair.madec_OM09}. 
    248248Second, the LF-RA becomes a truly quasi -second order scheme. 
    249249Indeed, \autoref{eq:STP_forcing} used in combination with a careful treatment of static instability 
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