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revision 1.1 by heimbach, Tue May 11 21:55:14 2004 UTC revision 1.7 by edhill, Sat Apr 8 01:50:50 2006 UTC
# Line 1  Line 1 
1  \section{The ECCO state estimation cost function DRAFT!!!  \section{The ECCO state estimation cost function DRAFT!!!
2  \label{sectioneccocost}}  \label{sectioneccocost}}
3    \begin{rawhtml}
4    <!-- CMIREDIR:ecco_cost: -->
5    \end{rawhtml}
6    
7    Author: Patrick Heimbach
8    
9  The current ECCO state estimation covers an $nYears = 11$ year  The current ECCO state estimation covers an $nYears = 11$ year
10  model trajectory.  model trajectory.
# Line 54  field & file name & deccription & unit \ Line 59  field & file name & deccription & unit \
59  \end{table}  \end{table}
60    
61    
62  \subsubsection{$nYears$ time mean SSH misfit}  \subsubsection{\textit{\textbf{nYears}} time mean SSH misfit}
63    
64  \begin{enumerate}  \begin{enumerate}
65  %  %
66  \item  \item
67  Compute 11yr model mean spatial distribution  Compute $nYears$ model mean spatial distribution
68  %  %
69  \begin{equation}  \begin{equation}
70  psmean(i,j)\, =\,  psmean(i,j)\, =\,
# Line 68  psbar(i,j) Line 73  psbar(i,j)
73  \end{equation}  \end{equation}
74  %  %
75  \item  \item
76  Compute global offset between 11-yr model and T/P mean:  Compute global offset between $nYears$ model and T/P mean:
77  %  %
78  \begin{equation}  \begin{equation}
79  \begin{split}  \begin{split}
# Line 161  cost_ssh Line 166  cost_ssh
166    
167  \end{verbatim}  \end{verbatim}
168    
169  \subsubsection{Weights}  \subsubsection{Weights and notes}
170    
171  \begin{itemize}  \begin{itemize}
172  %  %
# Line 227  sum over daily entries and plot daily av Line 232  sum over daily entries and plot daily av
232  \frac{1}{\text{daily entries}} \sum_{i,j} cost\_ssh\_anom(i,j,t)  \frac{1}{\text{daily entries}} \sum_{i,j} cost\_ssh\_anom(i,j,t)
233  \]  \]
234  \end{itemize}  \end{itemize}
235    
236    \subsection{Hydrographic constraints}
237    
238    Observation of temperature and salinity from various sources are
239    used to constrain the model. These are:
240    %
241    \begin{enumerate}
242    %
243    \item
244    CTD obs. for $T$, $S$ from various WOCE sections
245    %
246    \item
247    XBT obs. for $T$
248    %
249    \item
250    Sea surface temperature (SST) and salinity (SSS) from
251    Reynolds et al. (???)
252    %
253    \item
254    $T$, $S$ from ARGO floats
255    %
256    \item
257    $T$, $S$ from fields from Levitus (???)
258    %
259    \end{enumerate}
260    
261    \subsubsection{Input fields}
262    ~
263    
264    \begin{table}[h!]
265    \begin{center}
266    \begin{tabular}{lllc}
267    \hline \hline
268    ~&~&~&~\\
269    field & file name & deccription & unit \\
270    ~&~&~&~\\
271    \hline
272    ~&~&~&~\\
273    {\it tbar} & {\tt tbarfile} & monthly model mean pot. temperature &
274    [$^{\circ}\mathrm{C}$] \\
275    {\it sbar} & {\tt sbarfile} & monthly model mean salinity &
276    [ppt] \\
277    {\it tdat} & {\tt tdatfile} & monthly mean Levitus pot. temperature &
278    [$^{\circ}\mathrm{C}$] \\
279    {\it sdat} & {\tt sdatfile} & monthly mean Levitus salinity &
280    [ppt] \\
281    {\it ctdtobs}  & {\tt ctdtfile} & monthly WOCE CTD pot. temperature &
282    [$^{\circ}\mathrm{C}$] \\
283    {\it ctdsobs}  & {\tt ctdsfile} & monthly WOCE CTD salinity &
284    [ppt] \\
285    {\it xbtobs} & {\tt xbtfile} & monthly XBT in-situ(!) temperature &
286    [$^{\circ}\mathrm{C}$] \\
287    {\it sstdat}  & {\tt sstdatfile} & monthly Reynolds pot. SST &
288    [$^{\circ}\mathrm{C}$] \\
289    {\it sssdat}  & {\tt sssdatfile} & monthly Reynolds SSS &
290    [ppt] \\
291    {\it argotobs}  & {\tt argotfile} & monthly ARGO in-situ(!) temperature &
292    [$^{\circ}\mathrm{C}$] \\
293    {\it argosobs}  & {\tt argosfile} & monthly ARGO salinity &
294    [ppt] \\
295    {\it wti, wsi} & {\tt data\_errfile} & vert. stdev. profile for $T$, $S$ &
296    ~ \\
297    {\it wtvar} & {\tt temperrfile} & spatially varying stdev. & [$^{\circ}\mathrm{C}$] \\
298    {\it wsvar} & {\tt salterrfile} & spatially varying stdev. & [ppt] \\
299    ~&~&~&~\\
300    \hline \hline
301    \end{tabular}
302    \end{center}
303    \end{table}
304    
305    \subsubsection{XBT data}
306    
307    \begin{equation}
308    \begin{split}
309    cost\_xbt\_t(i,j,k) & = \,
310    \left[ \, \frac{fac \cdot ratio}{wti^2 + wtvar^2} \sum_{\tau=1}^{nMonsRec}
311    \left\{ Tbar(\tau) \, - \, T2\theta[xbtobs(\tau)] \right\}^2 \, \right](i,j,k)
312     \\
313    \end{split}
314    \end{equation}
315    
316    \subsubsection{WOCE CTD data}
317    
318    \begin{equation}
319    \begin{split}
320    cost\_ctd\_t(i,j,k) & = \,
321    \left[ \, \frac{fac \cdot ratio}{wti^2 + wtvar^2} \sum_{\tau=1}^{nMonsRec}
322    \left\{ Tbar(\tau) \, - \, ctdTobs(\tau) \right\}^2 \, \right](i,j,k)
323     \\
324    cost\_ctd\_s(i,j,k) & = \,
325    \left[ \, \frac{fac \cdot ratio}{wsi^2 + wsvar^2} \sum_{\tau=1}^{nMonsRec}
326    \left\{ Sbar(\tau) \, - \, ctdSobs(\tau) \right\}^2 \, \right](i,j,k)
327     \\
328    \end{split}
329    \end{equation}
330    
331    \subsubsection{ARGO float data}
332    
333    \begin{equation}
334    \begin{split}
335    cost\_argo\_t(i,j,k) & = \,
336    \left[ \, \frac{fac \cdot ratio}{wti^2 + wtvar^2} \sum_{\tau=1}^{nMonsRec}
337    \left\{ Tbar(\tau) \, - \, T2\theta[argoTobs(\tau)] \right\}^2 \, \right](i,j,k)
338     \\
339    cost\_argo\_s(i,j,k) & = \,
340    \left[ \, \frac{fac \cdot ratio}{wsi^2 + wsvar^2} \sum_{\tau=1}^{nMonsRec}
341    \left\{ Sbar(\tau) \, - \, argoSobs(\tau) \right\}^2 \, \right](i,j,k)
342     \\
343    \end{split}
344    \end{equation}
345    
346    \subsubsection{Reynolds sea surface T, S data}
347    
348    \begin{equation}
349    \begin{split}
350    cost\_sst(i,j) & = \,
351    \left[ \, wsst \sum_{\tau=1}^{nMonsRec}
352    \left\{ Tbar(\tau) \, - \, sstDat(\tau) \right\}^2 \, \right](i,j)
353     \\
354    cost\_sss(i,j) & = \,
355    \left[ \, wsss \sum_{\tau=1}^{nMonsRec}
356    \left\{ Sbar(\tau) \, - \, sssDat(\tau) \right\}^2 \, \right](i,j)
357     \\
358    \end{split}
359    \end{equation}
360    
361    \subsubsection{Levitus montly T, S climatological data}
362    
363    Model vs. data misfits are taken from $nYears$ monthly model means
364    vs. Levitus monthly data.
365    The description below is for potential temperature.
366    Procedure for salinity is fully analogous.
367    Spatial indices $(i,j,k)$ are omitted throughout.
368    %
369    \begin{enumerate}
370    %
371    \item
372    Compute $nYears$ monthly model means for each month $imon$:
373    \[
374    \overline{Tbar}(imon) \, = \, \frac{1}{nYears}
375    \sum_{iyear=1}^{nYears} Tbar(iyear,imon)
376    \]
377    %
378    \item
379    Compute misfit:
380    \[
381    cost\_theta(i,j,k) \, = \, \left[
382    \frac{fac \cdot ratio}{wti^2} \sum_{imon=1}^{12}
383    \left\{ \overline{Tbar}(imon) \, - \, Tdat(imon) \right\}^2  \right] (i,j,k)
384    \]
385    
386    \end{enumerate}
387    
388    
389    \subsubsection{Weights and notes}
390    
391    \begin{itemize}
392    %
393    \item
394    $T2\theta$ is an operator mapping in-situ to potential temperatures
395    %
396    \item
397    Latitudinal weight not used:
398    \[
399    cosphi(i,j) \, = \, 1
400    \]
401    %
402    \item
403    $ fac \, = \, cosphi \cdot mask $
404    %
405    \item
406    Spatially {\it constant} weights:
407    %
408    \begin{enumerate}
409    %
410    \item
411    Read standard deviation vertical profiles for $T$, $S$ \\
412    $ {\tt data\_errfile} \, \longrightarrow \,
413    wti(k), \,\, wsi(k) $ \\
414    $ {\tt data\_errfile} \, \longrightarrow \,
415    ratio = 0.25 = \left( \frac{1}{2} \right)^2 $
416    %
417    \item
418    Take inverse squares:
419    \[
420    \begin{split}
421    wtheta(k) & = \, \frac{ratio}{wti(k)^2} \\
422    wsalt(k) & = \, \frac{ratio}{wsi(k)^2} \\
423    \end{split}
424    \]
425    %
426    \end{enumerate}
427    %
428    \item
429    Spatially {\it varying} weights:
430    %
431    \begin{enumerate}
432    %
433    \item
434    Read standard deviation fields \\
435    $ {\tt temperrfile} \, \longrightarrow \, wtvar(i,j,k) $ \\
436    $ {\tt salterrfile} \, \longrightarrow \, wsvar(i,j,k) $ \\
437    %
438    \item
439    Weights are combination of spatially constant and varying parts:
440    \[
441    \begin{split}
442    wtheta2(i,j,k) & = \, \frac{ratio}
443    {wti(k)^2 \, + \,wtvar(i,j,k)^2 } \\
444    wsalt2(i,j,k) & = \,
445    \frac{ratio}
446    {wsi(k)^2 \, + \,wsvar(i,j,k)^2 } \\
447    \end{split}
448    \]
449    %
450    \end{enumerate}
451    %
452    \item
453    Sea surface $T$, $S$ weights:
454    \begin{itemize}
455    \item
456    SST: $ wsst \, = \, fac \cdot wtheta(1)$: horizontally constant
457    \item
458    SSS: $ wsss \, = \, fac \cdot wsalt2(i,j,1)$: horizontally varying
459    \end{itemize}
460    (Why this difference? I don't know.)
461    %
462    \end{itemize}
463    
464    
465    \subsubsection{Diagnostics}
466    
467    \begin{itemize}
468    %
469    \item
470    Map out $wtheta2(i,j,k)$, $wsalt2(i,j,k)$.
471    
472    %
473    \end{itemize}
474    

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