Changeset 11314 for NEMO/branches/2019/dev_r11233_obsasm_docfixes/doc/latex/NEMO/subfiles/chap_ASM.tex

Timestamp:

2019-07-19T19:04:20+02:00 (5 years ago)

Author:

djlea

Message:

#2297 Updates in response the P Mathiot's review

File:

• NEMO/branches/2019/dev_r11233_obsasm_docfixes/doc/latex/NEMO/subfiles/chap_ASM.tex (modified) (3 diffs)

NEMO/branches/2019/dev_r11233_obsasm_docfixes/doc/latex/NEMO/subfiles/chap_ASM.tex

@@ -100 +100 @@
 \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}
@@ -113 +116 @@
   \right.,
 \end{equation}
+
 where the divergence is defined as
+
 \[
   % \label{eq:asm_div}
@@ -120 +125 @@
       +\delta_j \left[ {e_{1v}\,e_{3v}\,v^{n-1}_I} \right]} \right).
 \]
+
 By the application of \autoref{eq:asm_dmp} the divergence is filtered in each iteration,
 and the vorticity is left unchanged.