# Changeset 781 for trunk/DOC/BETA/Chapters/Chap_LDF.tex

Ignore:
Timestamp:
2008-01-03T12:10:08+01:00 (13 years ago)
Message:

doc update, see ticket:1

File:
1 edited

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 r707 \item[$z$-coordinate with full step : ] in \eqref{Eq_ldfslp_iso} the densities appearing in the $i$ and $j$ derivatives  are taken at the same depth, thus the $in situ$ density can be used. it is not the case for the vertical derivatives. $\delta_{k+1/2}[\rho]$ is replaced by $-\rho N^2/g$, where $N^2$ is the local Brunt-Vais\"{a}l\"{a} frequency evaluated following \citet{McDougall1987} (see \S\ref{TRA_bn2}). \item[$z$-coordinate with partial step : ] the technique is identical to the full step case except that at partial step level, the \emph{horizontal} density gradient is evaluated as described in \S\ref{TRA_zps}. \item[$z$-coordinate with partial step : ] the technique is identical to the full step case except that at partial step level, the \emph{horizontal} density gradient is evaluated as described in \S\ref{TRA_zpshde}. \item[$s$- or hybrid $s$-$z$ coordinate : ] in the current release of \NEMO, there is no specific treatment for iso-neutral mixing in $s$-coordinate. In other word, iso-neutral mixing will only be accurately represented with a linear equation of state (\np{neos}=1 or 2). In the case of a "true" equation of state, the evaluation of $i$ and $j$ derivatives in \eqref{Eq_ldfslp_iso} will include a pressure dependent part, leading to a wrong evaluation of the neutral slopes.