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Changeset 11314 – NEMO

# Changeset 11314

Ignore:
Timestamp:
2019-07-19T19:04:20+02:00 (4 years ago)
Message:

#2297 Updates in response the P Mathiot's review

Location:
NEMO/branches/2019/dev_r11233_obsasm_docfixes/doc/latex/NEMO/subfiles
Files:
2 edited

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Unmodified
 r11311 \label{sec:ASM_div_dmp} The velocity increments may be initialized by the iterative application of a divergence damping operator. In iteration step $n$ new estimates of velocity increments $u^{n}_I$ and $v^{n}_I$ are updated by: It is quite challenging for data assimilation systems to provide non-divergent velocity increments. Applying divergent velocity increments will likely cause spurious vertical velocities in the model. This section describes a method to take velocity increments provided to \NEMO ($u^0_I$ and $v^0_I$) and adjust them by the iterative application of a divergence damping operator. The method is also described in \citet{dobricic.pinardi.ea_OS07}. In iteration step $n$ (starting at $n=1$) new estimates of velocity increments $u^{n}_I$ and $v^{n}_I$ are updated by: \begin{equation} \label{eq:asm_dmp} \right., \end{equation} where the divergence is defined as $% \label{eq:asm_div} +\delta_j \left[ {e_{1v}\,e_{3v}\,v^{n-1}_I} \right]} \right).$ By the application of \autoref{eq:asm_dmp} the divergence is filtered in each iteration, and the vorticity is left unchanged.