Changeset 3085 for branches/2011/dev_MERCATOR_INGV_2011_MERGE/DOC/TexFiles/Chapters/Chap_SBC.tex

Timestamp:

2011-11-14T14:13:32+01:00 (12 years ago)

Author:

cbricaud

Message:

commit changes from dev_INGV_2011

File:

• branches/2011/dev_MERCATOR_INGV_2011_MERGE/DOC/TexFiles/Chapters/Chap_SBC.tex (modified) (7 diffs)

branches/2011/dev_MERCATOR_INGV_2011_MERGE/DOC/TexFiles/Chapters/Chap_SBC.tex

@@ -24 +24 @@
 \end{itemize}
 
-Four different ways to provide the first six fields to the ocean are available which 
+Five different ways to provide the first six fields to the ocean are available which 
 are controlled by namelist variables: an analytical formulation (\np{ln\_ana}~=~true), 
 a flux formulation (\np{ln\_flx}~=~true), a bulk formulae formulation (CORE 
-(\np{ln\_core}~=~true) or CLIO (\np{ln\_clio}~=~true) bulk formulae) and a coupled 
+(\np{ln\_core}~=~true), CLIO (\np{ln\_clio}~=~true) or MFS
+\footnote { Note that MFS bulk formulae compute fluxes only for the ocean component}
+(\np{ln\_ecmwf}~=~true) bulk formulae) and a coupled 
 formulation (exchanges with a atmospheric model via the OASIS coupler) 
 (\np{ln\_cpl}~=~true). When used, the atmospheric pressure forces both 
-ocean and ice dynamics (\np{ln\_apr\_dyn}~=~true)
-\footnote{The surface pressure field could be use in bulk formulae, nevertheless 
-none of the current bulk formulea (CLIO and CORE) uses the it.}. 
+ocean and ice dynamics (\np{ln\_apr\_dyn}~=~true).
 The frequency at which the six or seven fields have to be updated is the \np{nn\_fsbc} 
 namelist parameter. 
@@ -46 +46 @@
 (\np{nn\_ice}~=~0,1, 2 or 3); the addition of river runoffs as surface freshwater 
 fluxes or lateral inflow (\np{ln\_rnf}~=~true); the addition of a freshwater flux adjustment 
-in order to avoid a mean sea-level drift (\np{nn\_fwb}~=~0,~1~or~2); and the 
+in order to avoid a mean sea-level drift (\np{nn\_fwb}~=~0,~1~or~2); the 
 transformation of the solar radiation (if provided as daily mean) into a diurnal 
-cycle (\np{ln\_dm2dc}~=~true).
+cycle (\np{ln\_dm2dc}~=~true); and a neutral drag coefficient can be read from an external wave 
+model (\np{ln\_cdgw}~=~true). The latter option is possible only in case core or ecmwf bulk formulas are selected.
 
 In this chapter, we first discuss where the surface boundary condition appears in the
-model equations. Then we present the four ways of providing the surface boundary condition, 
+model equations. Then we present the five ways of providing the surface boundary condition, 
 followed by the description of the atmospheric pressure and the river runoff. 
 Next the scheme for interpolation on the fly is described.
@@ -480 +481 @@
 % Bulk formulation
 % ================================================================
-\section  [Bulk formulation (\textit{sbcblk\_core} or \textit{sbcblk\_clio}) ]
-      {Bulk formulation \small{(\mdl{sbcblk\_core} or \mdl{sbcblk\_clio} module)} }
+\section  [Bulk formulation (\textit{sbcblk\_core}, \textit{sbcblk\_clio} or \textit{sbcblk\_ecmwf}) ]
+      {Bulk formulation \small{(\mdl{sbcblk\_core} \mdl{sbcblk\_clio} \mdl{sbcblk\_ecmwf} modules)} }
 \label{SBC_blk}
 
@@ -487 +488 @@
 using bulk formulae and atmospheric fields and ocean (and ice) variables. 
 
-The atmospheric fields used depend on the bulk formulae used. Two bulk formulations 
-are available : the CORE and CLIO bulk formulea. The choice is made by setting to true
-one of the following namelist variable : \np{ln\_core} and \np{ln\_clio}.
-
-Note : in forced mode, when a sea-ice model is used, a bulk formulation have to be used. 
-Therefore the two bulk formulea provided include the computation of the fluxes over both 
+The atmospheric fields used depend on the bulk formulae used. Three bulk formulations 
+are available : the CORE, the CLIO and the MFS bulk formulea. The choice is made by setting to true
+one of the following namelist variable : \np{ln\_core} ; \np{ln\_clio} or  \np{ln\_ecmwf}.
+
+Note : in forced mode, when a sea-ice model is used, a bulk formulation (CLIO or CORE) have to be used. 
+Therefore the two bulk (CLIO and CORE) formulea include the computation of the fluxes over both 
 an ocean and an ice surface. 
 
@@ -583 +584 @@
 namelist (see \S\ref{SBC_fldread}). 
 
+% -------------------------------------------------------------------------------------------------------------
+%        ECMWF Bulk formulea
+% -------------------------------------------------------------------------------------------------------------
+\subsection    [MFS Bulk formulea (\np{ln\_ecmwf}=true)]
+            {MFS Bulk formulea (\np{ln\_ecmwf}=true, \mdl{sbcblk\_ecmwf})}
+\label{SBC_blk_ecmwf}
+%------------------------------------------namsbc_ecmwf----------------------------------------------------
+\namdisplay{namsbc_ecmwf} 
+%----------------------------------------------------------------------------------------------------------
+
+The MFS (Mediterranean Forecasting System) bulk formulae have been developed by
+ \citet{Castellari_al_JMS1998}. 
+They have been designed to handle the ECMWF operational data and are currently 
+in use in the MFS operational system \citep{Tonani_al_OS08}, \citep{Oddo_al_OS09}.
+The wind stress computation uses a drag coefficient computed according to \citet{Hellerman_Rosenstein_JPO83}.
+The surface boundary condition for temperature involves the balance between surface solar radiation,
+net long-wave radiation, the latent and sensible heat fluxes.
+Solar radiation is dependent on cloud cover and is computed by means of
+an astronomical formula \citep{Reed_JPO77}. Albedo monthly values are from \citet{Payne_JAS72} 
+as means of the values at $40^{o}N$ and $30^{o}N$ for the Atlantic Ocean (hence the same latitudinal
+band of the Mediterranean Sea). The net long-wave radiation flux
+\citep{Bignami_al_JGR95} is a function of
+air temperature, sea-surface temperature, cloud cover and relative humidity.
+Sensible heat and latent heat fluxes are computed by classical
+bulk formulae parameterized according to \citet{Kondo1975}.
+Details on the bulk formulae used can be found in \citet{Maggiore_al_PCE98} and \citet{Castellari_al_JMS1998}.
+
+The required 7 input fields must be provided on the model Grid-T and  are:
+\begin{itemize}
+\item          Zonal Component of the 10m wind ($ms^{-1}$)  (\np{sn\_windi})
+\item          Meridional Component of the 10m wind ($ms^{-1}$)  (\np{sn\_windj})
+\item          Total Claud Cover (\%)  (\np{sn\_clc})
+\item          2m Air Temperature ($K$) (\np{sn\_tair})
+\item          2m Dew Point Temperature ($K$)  (\np{sn\_rhm})
+\item          Total Precipitation ${Kg} m^{-2} s^{-1}$ (\np{sn\_prec})
+\item          Mean Sea Level Pressure (${Pa}) (\np{sn\_msl})
+\end{itemize}
+% -------------------------------------------------------------------------------------------------------------
 % ================================================================
 % Coupled formulation
@@ -991 +1030 @@
 \end{description}
 
+% -------------------------------------------------------------------------------------------------------------
+%        Neutral Drag Coefficient from external wave model
+% -------------------------------------------------------------------------------------------------------------
+\subsection   [Neutral drag coefficient from external wave model (\textit{sbcwave})]
+                        {Neutral drag coefficient from external wave model (\mdl{sbcwave})}
+\label{SBC_wave}
+%------------------------------------------namwave----------------------------------------------------
+\namdisplay{namsbc_wave}
+%-------------------------------------------------------------------------------------------------------------
+\begin{description}
+
+In order to read a neutral drag coeff, from an external data source (i.e. a wave model), the 
+logical variable \np{ln\_cdgw}
+ in $namsbc$ namelist must be defined ${.true.}$. 
+The \mdl{sbcwave} module containing the routine \np{sbc\_wave} reads the
+namelist ${namsbc\_wave}$ (for external data names, locations, frequency, interpolation and all 
+the miscellanous options allowed by Input Data generic Interface see \S\ref{SBC_input}) 
+and a 2D field of neutral drag coefficient. Then using the routine 
+TURB\_CORE\_1Z or TURB\_CORE\_2Z, and starting from the neutral drag coefficent provided, the drag coefficient is computed according 
+to stable/unstable conditions of the air-sea interface following \citet{Large_Yeager_Rep04}.
+
+\end{description}
+
 % Griffies doc:
 % When running ocean-ice simulations, we are not explicitly representing land processes, such as rivers, catchment areas, snow accumulation, etc. However, to reduce model drift, it is important to balance the hydrological cycle in ocean-ice models. We thus need to prescribe some form of global normalization to the precipitation minus evaporation plus river runoff. The result of the normalization should be a global integrated zero net water input to the ocean-ice system over a chosen time scale. 
@@ -997 +1059 @@
 
 
-