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Changeset 14789 for NEMO/branches/2021/dev_r13747_HPC-11_mcastril_HPDAonline_DiagGPU/doc/latex/NEMO/subfiles/chap_SBC.tex – NEMO

Ignore:
Timestamp:
2021-05-05T13:18:04+02:00 (3 years ago)
Author:
mcastril
Message:

[2021/HPC-11_mcastril_HPDAonline_DiagGPU] Update externals

Location:
NEMO/branches/2021/dev_r13747_HPC-11_mcastril_HPDAonline_DiagGPU
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  • NEMO/branches/2021/dev_r13747_HPC-11_mcastril_HPDAonline_DiagGPU

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  • NEMO/branches/2021/dev_r13747_HPC-11_mcastril_HPDAonline_DiagGPU/doc/latex/NEMO/subfiles

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  • NEMO/branches/2021/dev_r13747_HPC-11_mcastril_HPDAonline_DiagGPU/doc/latex/NEMO/subfiles/chap_SBC.tex

    r13165 r14789  
    11\documentclass[../main/NEMO_manual]{subfiles} 
    2 \usepackage{fontspec} 
    3 \usepackage{fontawesome} 
    42 
    53\begin{document} 
    64 
    7 \chapter{Surface Boundary Condition (SBC, SAS, ISF, ICB)} 
     5\chapter{Surface Boundary Condition (SBC, SAS, ISF, ICB, TDE)} 
    86\label{chap:SBC} 
    9  
    10 \thispagestyle{plain} 
    117 
    128\chaptertoc 
     
    1814    Release & Author(s) & Modifications \\ 
    1915    \hline 
     16    {\em  next} & {\em Simon M{\" u}ller} & {\em Update of \autoref{sec:SBC_TDE}; revision of \autoref{subsec:SBC_fwb}}\\[2mm] 
     17    {\em  next} & {\em Pierre Mathiot} & {\em update of the ice shelf section (2019 developments)}\\[2mm]   
    2018    {\em   4.0} & {\em ...} & {\em ...} \\ 
    2119    {\em   3.6} & {\em ...} & {\em ...} \\ 
     
    7573  (\np[=0..3]{nn_ice}{nn\_ice}), 
    7674\item the addition of river runoffs as surface freshwater fluxes or lateral inflow (\np[=.true.]{ln_rnf}{ln\_rnf}), 
    77 \item the addition of ice-shelf melting as lateral inflow (parameterisation) or 
    78   as fluxes applied at the land-ice ocean interface (\np[=.true.]{ln_isf}{ln\_isf}), 
    7975\item the addition of a freshwater flux adjustment in order to avoid a mean sea-level drift 
    8076  (\np[=0..2]{nn_fwb}{nn\_fwb}), 
     
    10096One of these is modification by icebergs (see \autoref{sec:SBC_ICB_icebergs}), 
    10197which act as drifting sources of fresh water. 
    102 Another example of modification is that due to the ice shelf melting/freezing (see \autoref{sec:SBC_isf}), 
    103 which provides additional sources of fresh water. 
    10498 
    10599%% ================================================================================================= 
     
    525519See \autoref{subsec:SBC_ssr} for its specification. 
    526520 
    527  
    528  
    529  
    530  
    531  
    532  
    533 %% ================================================================================================= 
    534 \pagebreak 
    535 \newpage 
     521%% ================================================================================================= 
    536522\section[Bulk formulation (\textit{sbcblk.F90})]{Bulk formulation (\protect\mdl{sbcblk})} 
    537523\label{sec:SBC_blk} 
     
    557543 
    558544Note: all the NEMO Fortran routines involved in the present section have been 
    559  initially developed (and are still developed in parallel) in 
    560  the \href{https://brodeau.github.io/aerobulk/}{\texttt{AeroBulk}} open-source project 
    561 \citep{brodeau.barnier.ea_JPO17}. 
     545initially developed (and are still developed in parallel) in 
     546the \href{https://brodeau.github.io/aerobulk}{\texttt{AeroBulk}} open-source project 
     547\citep{brodeau.barnier.ea_JPO16}. 
    562548 
    563549%%% Bulk formulae are this: 
    564 \subsection{Bulk formulae}\label{subsec:SBC_blkform} 
    565 % 
     550\subsection{Bulk formulae} 
     551\label{subsec:SBC_blkform} 
     552 
    566553In NEMO, the set of equations that relate each component of the surface fluxes 
    567554to the near-surface atmosphere and sea surface states writes 
    568 % 
    569 \begin{subequations}\label{eq_bulk} 
     555 
     556\begin{subequations} 
     557  \label{eq:SBC_bulk} 
    570558  \label{eq:SBC_bulk_form} 
    571   \begin{eqnarray} 
    572     \mathbf{\tau} &=& \rho~ C_D ~ \mathbf{U}_z  ~ U_B \\ 
    573     Q_H           &=& \rho~C_H~C_P~\big[ \theta_z - T_s \big] ~ U_B \\ 
    574     E             &=& \rho~C_E    ~\big[    q_s   - q_z \big] ~ U_B \\ 
    575     Q_L           &=& -L_v \, E \\ 
    576     % 
    577     Q_{sr}        &=& (1 - a) Q_{sw\downarrow} \\ 
    578     Q_{ir}        &=& \delta (Q_{lw\downarrow} -\sigma T_s^4) 
    579   \end{eqnarray} 
     559  \begin{align} 
     560    \mathbf{\tau} &= \rho~ C_D ~ \mathbf{U}_z  ~ U_B \\ 
     561    Q_H           &= \rho~C_H~C_P~\big[ \theta_z - T_s \big] ~ U_B \\ 
     562    E             &= \rho~C_E    ~\big[    q_s   - q_z \big] ~ U_B \\ 
     563    Q_L           &= -L_v \, E \\ 
     564    Q_{sr}        &= (1 - a) Q_{sw\downarrow} \\ 
     565    Q_{ir}        &= \delta (Q_{lw\downarrow} -\sigma T_s^4) 
     566  \end{align} 
    580567\end{subequations} 
    581 % 
     568 
    582569with 
    583570   \[ \theta_z \simeq T_z+\gamma z \] 
    584571   \[  q_s \simeq 0.98\,q_{sat}(T_s,p_a ) \] 
    585 % 
    586572from which, the the non-solar heat flux is \[ Q_{ns} = Q_L + Q_H + Q_{ir} \] 
    587 % 
    588573where $\mathbf{\tau}$ is the wind stress vector, $Q_H$ the sensible heat flux, 
    589574$E$ the evaporation, $Q_L$ the latent heat flux, and $Q_{ir}$ the net longwave 
    590575flux. 
    591 % 
    592576$Q_{sw\downarrow}$ and $Q_{lw\downarrow}$ are the surface downwelling shortwave 
    593577and longwave radiative fluxes, respectively. 
    594 % 
    595578Note: a positive sign for $\mathbf{\tau}$, $Q_H$, $Q_L$, $Q_{sr}$ or $Q_{ir}$ 
    596579implies a gain of the relevant quantity for the ocean, while a positive $E$ 
    597580implies a freshwater loss for the ocean. 
    598 % 
    599581$\rho$ is the density of air. $C_D$, $C_H$ and $C_E$ are the bulk transfer 
    600582coefficients for momentum, sensible heat, and moisture, respectively. 
    601 % 
    602583$C_P$ is the heat capacity of moist air, and $L_v$ is the latent heat of 
    603584vaporization of water. 
    604 % 
    605585$\theta_z$, $T_z$ and $q_z$ are the potential temperature, absolute temperature, 
    606586and specific humidity of air at height $z$ above the sea surface, 
    607587respectively. $\gamma z$ is a temperature correction term which accounts for the 
    608588adiabatic lapse rate and approximates the potential temperature at height 
    609 $z$ \citep{josey.gulev.ea_2013}. 
    610 % 
     589$z$ \citep{josey.gulev.ea_OCC13}. 
    611590$\mathbf{U}_z$ is the wind speed vector at height $z$ above the sea surface 
    612 (possibly referenced to the surface current $\mathbf{u_0}$, 
    613 section \ref{s_res1}.\ref{ss_current}). 
    614 % 
     591(possibly referenced to the surface current $\mathbf{u_0}$).%, 
     592%\autoref{s_res1}.\autoref{ss_current}). %% Undefined references 
    615593The bulk scalar wind speed, namely $U_B$, is the scalar wind speed, 
    616594$|\mathbf{U}_z|$, with the potential inclusion of a gustiness contribution. 
    617 % 
    618595$a$ and $\delta$ are the albedo and emissivity of the sea surface, respectively.\\ 
    619 % 
    620596%$p_a$ is the mean sea-level pressure (SLP). 
    621 % 
    622597$T_s$ is the sea surface temperature. $q_s$ is the saturation specific humidity 
    623598of air at temperature $T_s$; it includes a 2\% reduction to account for the 
    624 presence of salt in seawater \citep{sverdrup.johnson.ea_1942,kraus.businger_QJRMS96}. 
     599presence of salt in seawater \citep{sverdrup.johnson.ea_bk42,kraus.businger_QJRMS96}. 
    625600Depending on the bulk parametrization used, $T_s$ can either be the temperature 
    626601at the air-sea interface (skin temperature, hereafter SSST) or at typically a 
    627602few tens of centimeters below the surface (bulk sea surface temperature, 
    628603hereafter SST). 
    629 % 
    630604The SSST differs from the SST due to the contributions of two effects of 
    631605opposite sign, the \emph{cool skin} and \emph{warm layer} (hereafter CS and WL, 
    632 respectively, see section\,\ref{subsec:SBC_skin}). 
    633 % 
     606respectively, see \autoref{subsec:SBC_skin}). 
    634607Technically, when the ECMWF or COARE* bulk parametrizations are selected 
    635608(\np[=.true.]{ln_ECMWF}{ln\_ECMWF} or \np[=.true.]{ln_COARE*}{ln\_COARE\*}), 
     
    639612 
    640613For more details on all these aspects the reader is invited to refer 
    641 to \citet{brodeau.barnier.ea_JPO17}. 
    642  
    643  
    644  
    645 \subsection{Bulk parametrizations}\label{subsec:SBC_blk_ocean} 
     614to \citet{brodeau.barnier.ea_JPO16}. 
     615 
     616\subsection{Bulk parametrizations} 
     617\label{subsec:SBC_blk_ocean} 
    646618%%%\label{subsec:SBC_param} 
    647619 
     
    653625height (from \np{rn_zqt}{rn\_zqt} to \np{rn_zu}{rn\_zu}). 
    654626 
    655  
    656  
    657627For the open ocean, four bulk parametrization algorithms are available in NEMO: 
     628 
    658629\begin{itemize} 
    659 \item NCAR, formerly known as CORE, \citep{large.yeager_rpt04,large.yeager_CD09} 
     630\item NCAR, formerly known as CORE, \citep{large.yeager_trpt04,large.yeager_CD09} 
    660631\item COARE 3.0 \citep{fairall.bradley.ea_JC03} 
    661632\item COARE 3.6 \citep{edson.jampana.ea_JPO13} 
     
    663634\end{itemize} 
    664635 
    665  
    666636With respect to version 3, the principal advances in version 3.6 of the COARE 
    667637bulk parametrization are built around improvements in the representation of the 
    668638effects of waves on 
    669 fluxes \citep{edson.jampana.ea_JPO13,brodeau.barnier.ea_JPO17}. This includes 
     639fluxes \citep{edson.jampana.ea_JPO13,brodeau.barnier.ea_JPO16}. This includes 
    670640improved relationships of surface roughness, and whitecap fraction on wave 
    671641parameters. It is therefore recommended to chose version 3.6 over 3. 
    672642 
    673  
    674  
    675  
    676 \subsection{Cool-skin and warm-layer parametrizations}\label{subsec:SBC_skin} 
    677 %\subsection[Cool-skin and warm-layer parameterizations 
    678 %(\forcode{ln_skin_cs} \& \forcode{ln_skin_wl})]{Cool-skin and warm-layer parameterizations (\protect\np{ln_skin_cs}{ln\_skin\_cs} \& \np{ln_skin_wl}{ln\_skin\_wl})} 
    679 %\label{subsec:SBC_skin} 
    680 % 
     643\subsection[Cool-skin and warm-layer parameterizations (   \forcode{ln_skin_cs}               \& \forcode{ln_skin_wl}              )] 
     644           {Cool-skin and warm-layer parameterizations (\protect\np{ln_skin_cs}{ln\_skin\_cs} \&      \np{ln_skin_wl}{ln\_skin\_wl})} 
     645\label{subsec:SBC_skin} 
     646 
    681647As opposed to the NCAR bulk parametrization, more advanced bulk 
    682648parametrizations such as COARE3.x and ECMWF are meant to be used with the skin 
    683649temperature $T_s$ rather than the bulk SST (which, in NEMO is the temperature at 
    684 the first T-point level, see section\,\ref{subsec:SBC_blkform}). 
    685 % 
     650the first T-point level, see \autoref{subsec:SBC_blkform}). 
     651 
    686652As such, the relevant cool-skin and warm-layer parametrization must be 
    687653activated through \np[=T]{ln_skin_cs}{ln\_skin\_cs} 
     
    692658 
    693659For the cool-skin scheme parametrization COARE and ECMWF algorithms share the same 
    694 basis: \citet{fairall.bradley.ea_JGR96}. With some minor updates based 
    695 on \citet{zeng.beljaars_GRL05} for ECMWF, and \citet{fairall.ea_19} for COARE 
     660basis: \citet{fairall.bradley.ea_JGRO96}. With some minor updates based 
     661on \citet{zeng.beljaars_GRL05} for ECMWF \iffalse, and \citet{fairall.ea_19?} for COARE \fi 
    6966623.6. 
    697663 
     
    700666turbulence input from Langmuir circulation). 
    701667 
    702 Importantly, COARE warm-layer scheme \citep{fairall.ea_19} includes a prognostic 
     668Importantly, COARE warm-layer scheme \iffalse \citep{fairall.ea_19?} \fi includes a prognostic 
    703669equation for the thickness of the warm-layer, while it is considered as constant 
    704670in the ECWMF algorithm. 
    705  
    706671 
    707672\subsection{Appropriate use of each bulk parametrization} 
     
    713678temperature is the bulk SST. Hence the following namelist parameters must be 
    714679set: 
    715 % 
    716 \begin{verbatim} 
     680 
     681\begin{forlines} 
    717682  ... 
    718683  ln_NCAR    = .true. 
     
    725690  ... 
    726691  ln_humi_sph = .true. ! humidity "sn_humi" is specific humidity  [kg/kg] 
    727 \end{verbatim} 
    728  
     692\end{forlines} 
    729693 
    730694\subsubsection{ECMWF} 
    731 % 
     695 
    732696With an atmospheric forcing based on a reanalysis of the ECMWF, such as the 
    733697Drakkar Forcing Set \citep{brodeau.barnier.ea_OM10}, we strongly recommend to 
     
    736700humidity are provided at the 2\,m height, and given that the humidity is 
    737701distributed as the dew-point temperature, the namelist must be tuned as follows: 
    738 % 
    739 \begin{verbatim} 
     702 
     703\begin{forlines} 
    740704  ... 
    741705  ln_ECMWF   = .true. 
     
    749713  ln_humi_dpt = .true. !  humidity "sn_humi" is dew-point temperature [K] 
    750714  ... 
    751 \end{verbatim} 
    752 % 
     715\end{forlines} 
     716 
    753717Note: when \np{ln_ECMWF}{ln\_ECMWF} is selected, the selection 
    754718of \np{ln_skin_cs}{ln\_skin\_cs} and \np{ln_skin_wl}{ln\_skin\_wl} implicitly 
     
    756720respectively (found in \textit{sbcblk\_skin\_ecmwf.F90}). 
    757721 
    758  
    759722\subsubsection{COARE 3.x} 
    760 % 
     723 
    761724Since the ECMWF parametrization is largely based on the COARE* parametrization, 
    762725the two algorithms are very similar in terms of structure and closure 
    763726approach. As such, the namelist tuning for COARE 3.x is identical to that of 
    764727ECMWF: 
    765 % 
    766 \begin{verbatim} 
     728 
     729\begin{forlines} 
    767730  ... 
    768731  ln_COARE3p6 = .true. 
     
    771734  ln_skin_wl = .true. ! use the warm-layer parameterization 
    772735  ... 
    773 \end{verbatim} 
     736\end{forlines} 
    774737 
    775738Note: when \np[=T]{ln_COARE3p0}{ln\_COARE3p0} is selected, the selection 
     
    778741respectively (found in \textit{sbcblk\_skin\_coare.F90}). 
    779742 
    780  
    781743%lulu 
    782  
    783  
    784744 
    785745% In a typical bulk algorithm, the BTCs under neutral stability conditions are 
     
    791751% and $q_z$. 
    792752 
    793  
    794  
    795753\subsection{Prescribed near-surface atmospheric state} 
    796754 
     
    799757different bulk formulae are used for the turbulent fluxes computation over the 
    800758ocean and over sea-ice surface. 
    801 % 
    802759 
    803760%The choice is made by setting to true one of the following namelist 
     
    861818the namsbc\_blk namelist (see \autoref{subsec:SBC_fldread}). 
    862819 
    863  
    864820\subsubsection{Air humidity} 
    865821 
     
    867823[kg/kg], relative humidity [\%], or dew-point temperature [K] (LINK to namelist 
    868824parameters)... 
    869  
    870  
    871 ~\\ 
    872  
    873  
    874  
    875  
    876  
    877  
    878  
    879  
    880  
    881825 
    882826%% ================================================================================================= 
     
    888832%their neutral transfer coefficients relationships with neutral wind. 
    889833%\begin{itemize} 
    890 %\item NCAR (\np[=.true.]{ln_NCAR}{ln\_NCAR}): The NCAR bulk formulae have been developed by \citet{large.yeager_rpt04}. 
     834%\item NCAR (\np[=.true.]{ln_NCAR}{ln\_NCAR}): The NCAR bulk formulae have been developed by \citet{large.yeager_trpt04}. 
    891835%  They have been designed to handle the NCAR forcing, a mixture of NCEP reanalysis and satellite data. 
    892836%  They use an inertial dissipative method to compute the turbulent transfer coefficients 
    893837%  (momentum, sensible heat and evaporation) from the 10m wind speed, air temperature and specific humidity. 
    894 %  This \citet{large.yeager_rpt04} dataset is available through 
     838%  This \citet{large.yeager_trpt04} dataset is available through 
    895839%  the \href{http://nomads.gfdl.noaa.gov/nomads/forms/mom4/NCAR.html}{GFDL web site}. 
    896840%  Note that substituting ERA40 to NCEP reanalysis fields does not require changes in the bulk formulea themself. 
     
    907851\label{subsec:SBC_blk_ice} 
    908852 
    909  
    910853\texttt{\#out\_of\_place:} 
    911854 For sea-ice, three possibilities can be selected: 
    912855a constant transfer coefficient (1.4e-3; default 
    913 value), \citet{lupkes.gryanik.ea_JGR12} (\np{ln_Cd_L12}{ln\_Cd\_L12}), 
     856value), \citet{lupkes.gryanik.ea_JGRA12} (\np{ln_Cd_L12}{ln\_Cd\_L12}), 
    914857and \citet{lupkes.gryanik_JGR15} (\np{ln_Cd_L15}{ln\_Cd\_L15}) parameterizations 
    915858\texttt{\#out\_of\_place.} 
    916859 
    917  
    918  
    919  
    920860Surface turbulent fluxes between sea-ice and the atmosphere can be computed in three different ways: 
    921861 
    922862\begin{itemize} 
    923 \item Constant value (\np[ Cd_ice=1.4e-3 ]{constant value}{constant\ value}): 
     863\item Constant value (\forcode{Cd_ice=1.4e-3}): 
    924864  default constant value used for momentum and heat neutral transfer coefficients 
    925 \item \citet{lupkes.gryanik.ea_JGR12} (\np[=.true.]{ln_Cd_L12}{ln\_Cd\_L12}): 
     865\item \citet{lupkes.gryanik.ea_JGRA12} (\np[=.true.]{ln_Cd_L12}{ln\_Cd\_L12}): 
    926866  This scheme adds a dependency on edges at leads, melt ponds and flows 
    927867  of the constant neutral air-ice drag. After some approximations, 
     
    1013953 
    1014954%% ================================================================================================= 
    1015 \section[Surface tides (\textit{sbctide.F90})]{Surface tides (\protect\mdl{sbctide})} 
    1016 \label{sec:SBC_tide} 
     955\section{Surface tides (TDE)} 
     956\label{sec:SBC_TDE} 
    1017957 
    1018958\begin{listing} 
     
    1022962\end{listing} 
    1023963 
    1024 The tidal forcing, generated by the gravity forces of the Earth-Moon and Earth-Sun sytems, 
    1025 is activated if \np{ln_tide}{ln\_tide} and \np{ln_tide_pot}{ln\_tide\_pot} are both set to \forcode{.true.} in \nam{_tide}{\_tide}. 
    1026 This translates as an additional barotropic force in the momentum \autoref{eq:MB_PE_dyn} such that: 
     964\subsection{Tidal constituents} 
     965Ocean model component TDE provides the common functionality for tidal forcing 
     966and tidal analysis in the model framework. This includes the computation of the gravitational 
     967surface forcing, as well as support for lateral forcing at open boundaries (see 
     968\autoref{subsec:LBC_bdy_tides}) and tidal harmonic analysis \iffalse (see 
     969\autoref{subsec:DIA_diamlr?} and \autoref{subsec:DIA_diadetide?}) \fi . The module is 
     970activated with \np[=.true.]{ln_tide}{ln\_tide} in namelist 
     971\nam{_tide}{\_tide}. It provides the same 34 tidal constituents that are 
     972included in the 
     973\href{https://www.aviso.altimetry.fr/en/data/products/auxiliary-products/global-tide-fes.html}{FES2014 
     974  ocean tide model}: Mf, Mm, Ssa, Mtm, Msf, Msqm, Sa, K1, O1, P1, Q1, J1, S1, 
     975M2, S2, N2, K2, nu2, mu2, 2N2, L2, T2, eps2, lam2, R2, M3, MKS2, MN4, MS4, M4, 
     976N4, S4, M6, and M8; see file \textit{tide.h90} and \mdl{tide\_mod} for further 
     977information and references\footnote{As a legacy option \np{ln_tide_var}{ln\_tide\_var} can be 
     978  set to \forcode{0}, in which case the 19 tidal constituents (M2, N2, 2N2, S2, 
     979  K2, K1, O1, Q1, P1, M4, Mf, Mm, Msqm, Mtm, S1, MU2, NU2, L2, and T2; see file 
     980  \textit{tide.h90}) and associated parameters that have been available in NEMO version 
     981  4.0 and earlier are available}. Constituents to be included in the tidal forcing 
     982(surface and lateral boundaries) are selected by enumerating their respective 
     983names in namelist array \np{sn_tide_cnames}{sn\_tide\_cnames}.\par 
     984 
     985\subsection{Surface tidal forcing} 
     986Surface tidal forcing can be represented in the model through an additional 
     987barotropic force in the momentum equation (\autoref{eq:MB_PE_dyn}) such that: 
    1027988\[ 
    1028   % \label{eq:SBC_PE_dyn_tides} 
    1029   \frac{\partial {\mathrm {\mathbf U}}_h }{\partial t}= ... 
    1030   +g\nabla (\Pi_{eq} + \Pi_{sal}) 
     989  \frac{\partial {\mathrm {\mathbf U}}_h }{\partial t} = \ldots +g\nabla (\gamma 
     990  \Pi_{eq} + \Pi_{sal}) 
    1031991\] 
    1032 where $\Pi_{eq}$ stands for the equilibrium tidal forcing and 
    1033 $\Pi_{sal}$ is a self-attraction and loading term (SAL). 
    1034  
    1035 The equilibrium tidal forcing is expressed as a sum over a subset of 
    1036 constituents chosen from the set of available tidal constituents 
    1037 defined in file \hf{SBC/tide} (this comprises the tidal 
    1038 constituents \textit{M2, N2, 2N2, S2, K2, K1, O1, Q1, P1, M4, Mf, Mm, 
    1039   Msqm, Mtm, S1, MU2, NU2, L2}, and \textit{T2}). Individual 
    1040 constituents are selected by including their names in the array 
    1041 \np{clname}{clname} in \nam{_tide}{\_tide} (e.g., \np{clname}{clname}\forcode{(1)='M2', } 
    1042 \np{clname}{clname}\forcode{(2)='S2'} to select solely the tidal consituents \textit{M2} 
    1043 and \textit{S2}). Optionally, when \np{ln_tide_ramp}{ln\_tide\_ramp} is set to 
    1044 \forcode{.true.}, the equilibrium tidal forcing can be ramped up 
    1045 linearly from zero during the initial \np{rdttideramp}{rdttideramp} days of the 
    1046 model run. 
     992where $\gamma \Pi_{eq}$ stands for the equilibrium tidal forcing scaled by a spatially 
     993uniform tilt factor $\gamma$, and $\Pi_{sal}$ is an optional 
     994self-attraction and loading term (SAL). These additional terms are enabled when, 
     995in addition to \np[=.true.]{ln_tide}{ln\_tide}), 
     996\np[=.true.]{ln_tide_pot}{ln\_tide\_pot}.\par 
     997 
     998The equilibrium tidal forcing is expressed as a sum over the subset of 
     999constituents listed in \np{sn_tide_cnames}{sn\_tide\_cnames} of 
     1000\nam{_tide} (e.g., 
     1001\begin{forlines} 
     1002      sn_tide_cnames(1) = 'M2' 
     1003      sn_tide_cnames(2) = 'K1' 
     1004      sn_tide_cnames(3) = 'S2' 
     1005      sn_tide_cnames(4) = 'O1' 
     1006\end{forlines} 
     1007to select the four tidal constituents of strongest equilibrium tidal 
     1008potential). The tidal tilt factor $\gamma = 1 + k - h$ includes the 
     1009Love numbers $k$ and $h$ \citep{love_PRSL09}; this factor is 
     1010configurable using \np{rn_tide_gamma}{rn\_tide\_gamma} (default value 0.7). Optionally, 
     1011when \np[=.true.]{ln_tide_ramp}{ln\_tide\_ramp}, the equilibrium tidal 
     1012forcing can be ramped up linearly from zero during the initial 
     1013\np{rn_tide_ramp_dt}{rn\_tide\_ramp\_dt} days of the model run.\par 
    10471014 
    10481015The SAL term should in principle be computed online as it depends on 
    10491016the model tidal prediction itself (see \citet{arbic.garner.ea_DSR04} for a 
    1050 discussion about the practical implementation of this term). 
    1051 Nevertheless, the complex calculations involved would make this 
    1052 computationally too expensive. Here, two options are available: 
    1053 $\Pi_{sal}$ generated by an external model can be read in 
    1054 (\np[=.true.]{ln_read_load}{ln\_read\_load}), or a ``scalar approximation'' can be 
    1055 used (\np[=.true.]{ln_scal_load}{ln\_scal\_load}). In the latter case 
     1017discussion about the practical implementation of this term). The complex 
     1018calculations involved in such computations, however, are computationally very 
     1019expensive. Here, two mutually exclusive simpler variants are available: 
     1020amplitudes generated by an external model for oscillatory $\Pi_{sal}$ 
     1021contributions from each of the selected tidal constituents can be read in 
     1022(\np[=.true.]{ln_read_load}{ln\_read\_load}) from the file specified in 
     1023\np{cn_tide_load}{cn\_tide\_load} (the variable names are comprised of the 
     1024tidal-constituent name and suffixes \forcode{_z1} and \forcode{_z2} for the two 
     1025orthogonal components, respectively); alternatively, a ``scalar approximation'' 
     1026can be used (\np[=.true.]{ln_scal_load}{ln\_scal\_load}), where 
    10561027\[ 
    10571028  \Pi_{sal} = \beta \eta, 
    10581029\] 
    1059 where $\beta$ (\np{rn_scal_load}{rn\_scal\_load} with a default value of 0.094) is a 
    1060 spatially constant scalar, often chosen to minimize tidal prediction 
    1061 errors. Setting both \np{ln_read_load}{ln\_read\_load} and \np{ln_scal_load}{ln\_scal\_load} to 
    1062 \forcode{.false.} removes the SAL contribution. 
     1030with a spatially uniform coefficient $\beta$, which can be configured 
     1031via \np{rn_scal_load}{rn\_scal\_load} (default value 0.094) and is 
     1032often tuned to minimize tidal prediction errors.\par 
     1033 
     1034For diagnostic purposes, the forcing potential of the individual tidal 
     1035constituents (incl. load ptential, if activated) and the total forcing 
     1036potential (incl. load potential, if activated) can be made available 
     1037as diagnostic output by setting 
     1038\np[=.true.]{ln_tide_dia}{ln\_tide\_dia} (fields 
     1039\forcode{tide_pot_<constituent>} and \forcode{tide_pot}).\par 
    10631040 
    10641041%% ================================================================================================= 
     
    12011178 
    12021179%% ================================================================================================= 
    1203 \section[Ice shelf melting (\textit{sbcisf.F90})]{Ice shelf melting (\protect\mdl{sbcisf})} 
     1180\section[Ice Shelf (ISF)]{Interaction with ice shelves (ISF)} 
    12041181\label{sec:SBC_isf} 
    12051182 
    12061183\begin{listing} 
    1207   \nlst{namsbc_isf} 
    1208   \caption{\forcode{&namsbc_isf}} 
    1209   \label{lst:namsbc_isf} 
     1184  \nlst{namisf} 
     1185  \caption{\forcode{&namisf}} 
     1186  \label{lst:namisf} 
    12101187\end{listing} 
    12111188 
    1212 The namelist variable in \nam{sbc}{sbc}, \np{nn_isf}{nn\_isf}, controls the ice shelf representation. 
    1213 Description and result of sensitivity test to \np{nn_isf}{nn\_isf} are presented in \citet{mathiot.jenkins.ea_GMD17}. 
    1214 The different options are illustrated in \autoref{fig:SBC_isf}. 
    1215  
     1189The namelist variable in \nam{isf}{isf}, \np{ln_isf}{ln\_isf}, controls the ice shelf interactions: 
    12161190\begin{description} 
    1217   \item [{\np[=1]{nn_isf}{nn\_isf}}]: The ice shelf cavity is represented (\np[=.true.]{ln_isfcav}{ln\_isfcav} needed). 
    1218   The fwf and heat flux are depending of the local water properties. 
    1219  
    1220   Two different bulk formulae are available: 
     1191   \item $\bullet$ representation of the ice shelf/ocean melting/freezing for opened cavity (cav, \np{ln_isfcav_mlt}{ln\_isfcav\_mlt}). 
     1192   \item $\bullet$ parametrisation of the ice shelf/ocean melting/freezing for closed cavities (par, \np{ln_isfpar_mlt}{ln\_isfpar\_mlt}). 
     1193   \item $\bullet$ coupling with an ice sheet model (\np{ln_isfcpl}{ln\_isfcpl}). 
     1194\end{description} 
     1195 
     1196  \subsection{Ocean/Ice shelf fluxes in opened cavities} 
     1197 
     1198     \np{ln_isfcav_mlt}{ln\_isfcav\_mlt}\forcode{ = .true.} activates the ocean/ice shelf thermodynamics interactions at the ice shelf/ocean interface.  
     1199     If \np{ln_isfcav_mlt}{ln\_isfcav\_mlt}\forcode{ = .false.}, thermodynamics interactions are desctivated but the ocean dynamics inside the cavity is still active. 
     1200     The logical flag \np{ln_isfcav}{ln\_isfcav} control whether or not the ice shelf cavities are closed. \np{ln_isfcav}{ln\_isfcav} is not defined in the namelist but in the domcfg.nc input file.\\ 
     1201 
     1202     3 options are available to represent to ice-shelf/ocean fluxes at the interface: 
     1203     \begin{description} 
     1204        \item[\np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = 'spe'}]: 
     1205        The fresh water flux is specified by a forcing fields \np{sn_isfcav_fwf}{sn\_isfcav\_fwf}. Convention of the input file is: positive toward the ocean (i.e. positive for melting and negative for freezing). 
     1206        The latent heat fluxes is derived from the fresh water flux.  
     1207        The heat content flux is derived from the fwf flux assuming a temperature set to the freezing point in the top boundary layer (\np{rn_htbl}{rn\_htbl}) 
     1208 
     1209        \item[\np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = 'oasis'}]: 
     1210        The \forcode{'oasis'} is a prototype of what could be a method to spread precipitation on Antarctic ice sheet as ice shelf melt inside the cavity when a coupled model Atmosphere/Ocean is used.  
     1211        It has not been tested and therefore the model will stop if you try to use it.  
     1212        Actions will be undertake in 2020 to build a comprehensive interface to do so for Greenland, Antarctic and ice shelf (cav), ice shelf (par), icebergs, subglacial runoff and runoff. 
     1213 
     1214        \item[\np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = '2eq'}]: 
     1215        The heat flux and the fresh water flux (negative for melting) resulting from ice shelf melting/freezing are parameterized following \citet{Grosfeld1997}.  
     1216        This formulation is based on a balance between the vertical diffusive heat flux across the ocean top boundary layer (\autoref{eq:ISOMIP1})  
     1217        and the latent heat due to melting/freezing (\autoref{eq:ISOMIP2}): 
     1218 
     1219        \begin{equation} 
     1220        \label{eq:ISOMIP1} 
     1221        \mathcal{Q}_h = \rho c_p \gamma (T_w - T_f) 
     1222        \end{equation} 
     1223        \begin{equation} 
     1224        \label{eq:ISOMIP2} 
     1225        q = \frac{-\mathcal{Q}_h}{L_f} 
     1226        \end{equation} 
     1227         
     1228        where $\mathcal{Q}_h$($W.m^{-2}$) is the heat flux,q($kg.s^{-1}m^{-2}$) the fresh-water flux,  
     1229        $L_f$ the specific latent heat, $T_w$ the temperature averaged over a boundary layer below the ice shelf (explained below),  
     1230        $T_f$ the freezing point using  the  pressure  at  the  ice  shelf  base  and  the  salinity  of the water in the boundary layer,  
     1231        and $\gamma$ the thermal exchange coefficient. 
     1232 
     1233        \item[\np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = '3eq'}]: 
     1234        For realistic studies, the heat and freshwater fluxes are parameterized following \citep{Jenkins2001}. This formulation is based on three equations:  
     1235        a balance between the vertical diffusive heat flux across the boundary layer  
     1236        , the latent heat due to melting/freezing of ice and the vertical diffusive heat flux into the ice shelf (\autoref{eq:3eq1});  
     1237        a balance between the vertical diffusive salt flux across the boundary layer and the salt source or sink represented by the melting/freezing (\autoref{eq:3eq2});  
     1238        and a linear equation for the freezing temperature of sea water (\autoref{eq:3eq3}, detailed of the linearisation coefficient in \citet{AsayDavis2016}): 
     1239 
     1240        \begin{equation} 
     1241        \label{eq:3eq1} 
     1242        c_p \rho \gamma_T (T_w-T_b) = -L_f q - \rho_i c_{p,i} \kappa \frac{T_s - T_b}{h_{isf}} 
     1243        \end{equation} 
     1244        \begin{equation} 
     1245        \label{eq:3eq2} 
     1246        \rho \gamma_S (S_w - S_b) = (S_i - S_b)q 
     1247        \end{equation} 
     1248        \begin{equation} 
     1249        \label{eq:3eq3} 
     1250        T_b = \lambda_1 S_b + \lambda_2 +\lambda_3 z_{isf} 
     1251        \end{equation} 
     1252 
     1253        where $T_b$ is the temperature at the interface, $S_b$ the salinity at the interface, $\gamma_T$ and $\gamma_S$ the exchange coefficients for temperature and salt, respectively,  
     1254        $S_i$ the salinity of the ice (assumed to be 0), $h_{isf}$ the ice shelf thickness, $z_{isf}$ the ice shelf draft, $\rho_i$ the density of the iceshelf,  
     1255        $c_{p,i}$ the specific heat capacity of the ice, $\kappa$ the thermal diffusivity of the ice  
     1256        and $T_s$ the atmospheric surface temperature (at the ice/air interface, assumed to be -20C).  
     1257        The Liquidus slope ($\lambda_1$), the liquidus intercept ($\lambda_2$) and the Liquidus pressure coefficient ($\lambda_3$)  
     1258        for TEOS80 and TEOS10 are described in \citep{AsayDavis2016} and in \citep{Jourdain2017}. 
     1259        The linear system formed by \autoref{eq:3eq1}, \autoref{eq:3eq2} and the linearised equation for the freezing temperature of sea water (\autoref{eq:3eq3}) can be solved for $S_b$ or $T_b$.  
     1260        Afterward, the freshwater flux ($q$) and the heat flux ($\mathcal{Q}_h$) can be computed. 
     1261 
     1262     \end{description} 
     1263 
     1264     \begin{table}[h] 
     1265        \centering 
     1266        \caption{Description of the parameters hard coded into the ISF module} 
     1267        \label{tab:isf} 
     1268        \begin{tabular}{|l|l|l|l|} 
     1269        \hline 
     1270        Symbol    & Description               & Value              & Unit               \\ 
     1271        \hline 
     1272        $C_p$     & Ocean specific heat       & 3992               & $J.kg^{-1}.K^{-1}$ \\ 
     1273        $L_f$     & Ice latent heat of fusion & $3.34 \times 10^5$ & $J.kg^{-1}$        \\ 
     1274        $C_{p,i}$ & Ice specific heat         & 2000               & $J.kg^{-1}.K^{-1}$ \\ 
     1275        $\kappa$  & Heat diffusivity          & $1.54 \times 10^{-6}$& $m^2.s^{-1}$     \\ 
     1276        $\rho_i$  & Ice density               & 920                & $kg.m^3$           \\ 
     1277        \hline 
     1278        \end{tabular} 
     1279     \end{table} 
     1280 
     1281     Temperature and salinity used to compute the fluxes in \autoref{eq:ISOMIP1}, \autoref{eq:3eq1} and \autoref{eq:3eq2} are the average temperature in the top boundary layer \citep{losch_JGR08}.  
     1282     Its thickness is defined by \np{rn_htbl}{rn\_htbl}. 
     1283     The fluxes and friction velocity are computed using the mean temperature, salinity and velocity in the first \np{rn_htbl}{rn\_htbl} m. 
     1284     Then, the fluxes are spread over the same thickness (ie over one or several cells). 
     1285     If \np{rn_htbl}{rn\_htbl} is larger than top $e_{3}t$, there is no more direct feedback between the freezing point at the interface and the top cell temperature. 
     1286     This can lead to super-cool temperature in the top cell under melting condition. 
     1287     If \np{rn_htbl}{rn\_htbl} smaller than top $e_{3}t$, the top boundary layer thickness is set to the top cell thickness.\\ 
     1288 
     1289     Each melt formula (\np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = '3eq'} or \np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = '2eq'}) depends on an exchange coeficient ($\Gamma^{T,S}$) between the ocean and the ice. 
     1290     Below, the exchange coeficient $\Gamma^{T}$ and $\Gamma^{S}$ are respectively defined by \np{rn_gammat0}{rn\_gammat0} and \np{rn_gammas0}{rn\_gammas0}.  
     1291     There are 3 different ways to compute the exchange velocity: 
     1292 
     1293     \begin{description} 
     1294        \item[\np{cn_gammablk}{cn\_gammablk}\forcode{='spe'}]: 
     1295        The salt and heat exchange coefficients are constant and defined by: 
     1296\[ 
     1297\gamma^{T} = \Gamma^{T} 
     1298\] 
     1299\[ 
     1300\gamma^{S} = \Gamma^{S} 
     1301\]  
     1302        This is the recommended formulation for ISOMIP. 
     1303 
     1304   \item[\np{cn_gammablk}{cn\_gammablk}\forcode{='vel'}]: 
     1305        The salt and heat exchange coefficients are velocity dependent and defined as 
     1306\[ 
     1307\gamma^{T} = \Gamma^{T} \times u_{*}  
     1308\] 
     1309\[ 
     1310\gamma^{S} = \Gamma^{S} \times u_{*} 
     1311\] 
     1312        where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_htbl}{rn\_htbl} meters). 
     1313        See \citet{jenkins.nicholls.ea_JPO10} for all the details on this formulation. It is the recommended formulation for realistic application and ISOMIP+/MISOMIP configuration. 
     1314 
     1315   \item[\np{cn_gammablk}{cn\_gammablk}\forcode{'vel\_stab'}]: 
     1316        The salt and heat exchange coefficients are velocity and stability dependent and defined as: 
     1317\[ 
     1318\gamma^{T,S} = \frac{u_{*}}{\Gamma_{Turb} + \Gamma^{T,S}_{Mole}}  
     1319\] 
     1320        where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_tbl}{rn\_htbl} meters), 
     1321        $\Gamma_{Turb}$ the contribution of the ocean stability and 
     1322        $\Gamma^{T,S}_{Mole}$ the contribution of the molecular diffusion. 
     1323        See \citet{holland.jenkins_JPO99} for all the details on this formulation.  
     1324        This formulation has not been extensively tested in NEMO (not recommended). 
     1325     \end{description} 
     1326 
     1327\subsection{Ocean/Ice shelf fluxes in parametrised cavities} 
    12211328 
    12221329  \begin{description} 
    1223   \item [{\np[=1]{nn_isfblk}{nn\_isfblk}}]: The melt rate is based on a balance between the upward ocean heat flux and 
    1224     the latent heat flux at the ice shelf base. A complete description is available in \citet{hunter_rpt06}. 
    1225   \item [{\np[=2]{nn_isfblk}{nn\_isfblk}}]: The melt rate and the heat flux are based on a 3 equations formulation 
    1226     (a heat flux budget at the ice base, a salt flux budget at the ice base and a linearised freezing point temperature equation). 
    1227     A complete description is available in \citet{jenkins_JGR91}. 
     1330 
     1331     \item[\np{cn_isfpar_mlt}{cn\_isfpar\_mlt}\forcode{ = 'bg03'}]: 
     1332     The ice shelf cavities are not represented. 
     1333     The fwf and heat flux are computed using the \citet{beckmann.goosse_OM03} parameterisation of isf melting. 
     1334     The fluxes are distributed along the ice shelf edge between the depth of the average grounding line (GL) 
     1335     (\np{sn_isfpar_zmax}{sn\_isfpar\_zmax}) and the base of the ice shelf along the calving front 
     1336     (\np{sn_isfpar_zmin}{sn\_isfpar\_zmin}) as in (\np{cn_isfpar_mlt}{cn\_isfpar\_mlt}\forcode{ = 'spe'}). 
     1337     The effective melting length (\np{sn_isfpar_Leff}{sn\_isfpar\_Leff}) is read from a file. 
     1338     This parametrisation has not been tested since a while and based on \citet{Favier2019},  
     1339     this parametrisation should probably not be used. 
     1340 
     1341     \item[\np{cn_isfpar_mlt}{cn\_isfpar\_mlt}\forcode{ = 'spe'}]: 
     1342     The ice shelf cavity is not represented. 
     1343     The fwf (\np{sn_isfpar_fwf}{sn\_isfpar\_fwf}) is prescribed and distributed along the ice shelf edge between 
     1344     the depth of the average grounding line (GL) (\np{sn_isfpar_zmax}{sn\_isfpar\_zmax}) and 
     1345     the base of the ice shelf along the calving front (\np{sn_isfpar_zmin}{sn\_isfpar\_min}). Convention of the input file is positive toward the ocean (i.e. positive for melting and negative for freezing). 
     1346     The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 
     1347 
     1348     \item[\np{cn_isfpar_mlt}{cn\_isfpar\_mlt}\forcode{ = 'oasis'}]: 
     1349     The \forcode{'oasis'} is a prototype of what could be a method to spread precipitation on Antarctic ice sheet as ice shelf melt inside the cavity when a coupled model Atmosphere/Ocean is used.  
     1350     It has not been tested and therefore the model will stop if you try to use it.  
     1351     Action will be undertake in 2020 to build a comprehensive interface to do so for Greenland, Antarctic and ice shelf (cav), ice shelf (par), icebergs, subglacial runoff and runoff. 
     1352 
    12281353  \end{description} 
    12291354 
    1230   Temperature and salinity used to compute the melt are the average temperature in the top boundary layer \citet{losch_JGR08}. 
    1231   Its thickness is defined by \np{rn_hisf_tbl}{rn\_hisf\_tbl}. 
    1232   The fluxes and friction velocity are computed using the mean temperature, salinity and velocity in the the first \np{rn_hisf_tbl}{rn\_hisf\_tbl} m. 
    1233   Then, the fluxes are spread over the same thickness (ie over one or several cells). 
    1234   If \np{rn_hisf_tbl}{rn\_hisf\_tbl} larger than top $e_{3}t$, there is no more feedback between the freezing point at the interface and the the top cell temperature. 
    1235   This can lead to super-cool temperature in the top cell under melting condition. 
    1236   If \np{rn_hisf_tbl}{rn\_hisf\_tbl} smaller than top $e_{3}t$, the top boundary layer thickness is set to the top cell thickness.\\ 
    1237  
    1238   Each melt bulk formula depends on a exchange coeficient ($\Gamma^{T,S}$) between the ocean and the ice. 
    1239   There are 3 different ways to compute the exchange coeficient: 
    1240   \begin{description} 
    1241   \item [{\np[=0]{nn_gammablk}{nn\_gammablk}}]: The salt and heat exchange coefficients are constant and defined by \np{rn_gammas0}{rn\_gammas0} and \np{rn_gammat0}{rn\_gammat0}. 
    1242     \begin{gather*} 
    1243        % \label{eq:SBC_isf_gamma_iso} 
    1244       \gamma^{T} = rn\_gammat0 \\ 
    1245       \gamma^{S} = rn\_gammas0 
    1246     \end{gather*} 
    1247     This is the recommended formulation for ISOMIP. 
    1248   \item [{\np[=1]{nn_gammablk}{nn\_gammablk}}]: The salt and heat exchange coefficients are velocity dependent and defined as 
    1249     \begin{gather*} 
    1250       \gamma^{T} = rn\_gammat0 \times u_{*} \\ 
    1251       \gamma^{S} = rn\_gammas0 \times u_{*} 
    1252     \end{gather*} 
    1253     where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_hisf_tbl}{rn\_hisf\_tbl} meters). 
    1254     See \citet{jenkins.nicholls.ea_JPO10} for all the details on this formulation. It is the recommended formulation for realistic application. 
    1255   \item [{\np[=2]{nn_gammablk}{nn\_gammablk}}]: The salt and heat exchange coefficients are velocity and stability dependent and defined as: 
    1256     \[ 
    1257       \gamma^{T,S} = \frac{u_{*}}{\Gamma_{Turb} + \Gamma^{T,S}_{Mole}} 
    1258     \] 
    1259     where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_hisf_tbl}{rn\_hisf\_tbl} meters), 
    1260     $\Gamma_{Turb}$ the contribution of the ocean stability and 
    1261     $\Gamma^{T,S}_{Mole}$ the contribution of the molecular diffusion. 
    1262     See \citet{holland.jenkins_JPO99} for all the details on this formulation. 
    1263     This formulation has not been extensively tested in \NEMO\ (not recommended). 
    1264   \end{description} 
    1265 \item [{\np[=2]{nn_isf}{nn\_isf}}]: The ice shelf cavity is not represented. 
    1266   The fwf and heat flux are computed using the \citet{beckmann.goosse_OM03} parameterisation of isf melting. 
    1267   The fluxes are distributed along the ice shelf edge between the depth of the average grounding line (GL) 
    1268   (\np{sn_depmax_isf}{sn\_depmax\_isf}) and the base of the ice shelf along the calving front 
    1269   (\np{sn_depmin_isf}{sn\_depmin\_isf}) as in (\np[=3]{nn_isf}{nn\_isf}). 
    1270   The effective melting length (\np{sn_Leff_isf}{sn\_Leff\_isf}) is read from a file. 
    1271 \item [{\np[=3]{nn_isf}{nn\_isf}}]: The ice shelf cavity is not represented. 
    1272   The fwf (\np{sn_rnfisf}{sn\_rnfisf}) is prescribed and distributed along the ice shelf edge between 
    1273   the depth of the average grounding line (GL) (\np{sn_depmax_isf}{sn\_depmax\_isf}) and 
    1274   the base of the ice shelf along the calving front (\np{sn_depmin_isf}{sn\_depmin\_isf}). 
    1275   The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 
    1276 \item [{\np[=4]{nn_isf}{nn\_isf}}]: The ice shelf cavity is opened (\np[=.true.]{ln_isfcav}{ln\_isfcav} needed). 
    1277   However, the fwf is not computed but specified from file \np{sn_fwfisf}{sn\_fwfisf}). 
    1278   The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 
    1279   As in \np[=1]{nn_isf}{nn\_isf}, the fluxes are spread over the top boundary layer thickness (\np{rn_hisf_tbl}{rn\_hisf\_tbl}) 
    1280 \end{description} 
    1281  
    1282 $\bullet$ \np[=1]{nn_isf}{nn\_isf} and \np[=2]{nn_isf}{nn\_isf} compute a melt rate based on 
     1355\np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = '2eq'}, \np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = '3eq'} and \np{cn_isfpar_mlt}{cn\_isfpar\_mlt}\forcode{ = 'bg03'} compute a melt rate based on 
    12831356the water mass properties, ocean velocities and depth. 
    1284 This flux is thus highly dependent of the model resolution (horizontal and vertical), 
    1285 realism of the water masses onto the shelf ...\\ 
    1286  
    1287 $\bullet$ \np[=3]{nn_isf}{nn\_isf} and \np[=4]{nn_isf}{nn\_isf} read the melt rate from a file. 
     1357The resulting fluxes are thus highly dependent of the model resolution (horizontal and vertical) and  
     1358realism of the water masses onto the shelf.\\ 
     1359 
     1360\np{cn_isfcav_mlt}{cn\_isfcav\_mlt}\forcode{ = 'spe'} and \np{cn_isfpar_mlt}{cn\_isfpar\_mlt}\forcode{ = 'spe'} read the melt rate from a file. 
    12881361You have total control of the fwf forcing. 
    12891362This can be useful if the water masses on the shelf are not realistic or 
    12901363the resolution (horizontal/vertical) are too coarse to have realistic melting or 
    1291 for studies where you need to control your heat and fw input.\\ 
    1292  
    1293 The ice shelf melt is implemented as a volume flux as for the runoff. 
    1294 The fw addition due to the ice shelf melting is, at each relevant depth level, added to 
    1295 the horizontal divergence (\textit{hdivn}) in the subroutine \rou{sbc\_isf\_div}, called from \mdl{divhor}. 
     1364for studies where you need to control your heat and fw input.  
     1365However, if your forcing is not consistent with the dynamics below you can reach unrealistic low water temperature.\\ 
     1366 
     1367The ice shelf fwf is implemented as a volume flux as for the runoff. 
     1368The fwf addition due to the ice shelf melting is, at each relevant depth level, added to 
     1369the horizontal divergence (\textit{hdivn}) in the subroutine \rou{isf\_hdiv}, called from \mdl{divhor}. 
    12961370See the runoff section \autoref{sec:SBC_rnf} for all the details about the divergence correction.\\ 
     1371 
     1372Description and result of sensitivity tests to \np{ln_isfcav_mlt}{ln\_isfcav\_mlt} and \np{ln_isfpar_mlt}{ln\_isfpar\_mlt} are presented in \citet{mathiot.jenkins.ea_GMD17}.  
     1373The different options are illustrated in \autoref{fig:ISF}. 
    12971374 
    12981375\begin{figure}[!t] 
    12991376  \centering 
    1300   \includegraphics[width=0.66\textwidth]{SBC_isf} 
     1377  \includegraphics[width=0.66\textwidth]{SBC_isf_v4.2} 
    13011378  \caption[Ice shelf location and fresh water flux definition]{ 
    13021379    Illustration of the location where the fwf is injected and 
    1303     whether or not the fwf is interactif or not depending of \protect\np{nn_isf}{nn\_isf}.} 
    1304   \label{fig:SBC_isf} 
     1380    whether or not the fwf is interactive or not.} 
     1381  \label{fig:ISF} 
    13051382\end{figure} 
    13061383 
    1307 %% ================================================================================================= 
    1308 \section{Ice sheet coupling} 
    1309 \label{sec:SBC_iscpl} 
    1310  
    1311 \begin{listing} 
    1312   \nlst{namsbc_iscpl} 
    1313   \caption{\forcode{&namsbc_iscpl}} 
    1314   \label{lst:namsbc_iscpl} 
    1315 \end{listing} 
     1384\subsection{Available outputs} 
     1385The following outputs are availables via XIOS: 
     1386\begin{description} 
     1387   \item[for parametrised cavities]: 
     1388      \begin{xmllines} 
     1389 <field id="isftfrz_par"     long_name="freezing point temperature in the parametrization boundary layer" unit="degC"     /> 
     1390 <field id="fwfisf_par"      long_name="Ice shelf melt rate"                           unit="kg/m2/s"  /> 
     1391 <field id="qoceisf_par"     long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     /> 
     1392 <field id="qlatisf_par"     long_name="Ice shelf latent heat flux"                    unit="W/m2"     /> 
     1393 <field id="qhcisf_par"      long_name="Ice shelf heat content flux of injected water" unit="W/m2"     /> 
     1394 <field id="fwfisf3d_par"    long_name="Ice shelf melt rate"                           unit="kg/m2/s"  grid_ref="grid_T_3D" /> 
     1395 <field id="qoceisf3d_par"   long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1396 <field id="qlatisf3d_par"   long_name="Ice shelf latent heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1397 <field id="qhcisf3d_par"    long_name="Ice shelf heat content flux of injected water" unit="W/m2"     grid_ref="grid_T_3D" /> 
     1398 <field id="ttbl_par"        long_name="temperature in the parametrisation boundary layer" unit="degC" /> 
     1399 <field id="isfthermald_par" long_name="thermal driving of ice shelf melting"          unit="degC"     /> 
     1400      \end{xmllines} 
     1401   \item[for open cavities]: 
     1402      \begin{xmllines} 
     1403 <field id="isftfrz_cav"     long_name="freezing point temperature at ocean/isf interface"                unit="degC"     /> 
     1404 <field id="fwfisf_cav"      long_name="Ice shelf melt rate"                           unit="kg/m2/s"  /> 
     1405 <field id="qoceisf_cav"     long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     /> 
     1406 <field id="qlatisf_cav"     long_name="Ice shelf latent heat flux"                    unit="W/m2"     /> 
     1407 <field id="qhcisf_cav"      long_name="Ice shelf heat content flux of injected water" unit="W/m2"     /> 
     1408 <field id="fwfisf3d_cav"    long_name="Ice shelf melt rate"                           unit="kg/m2/s"  grid_ref="grid_T_3D" /> 
     1409 <field id="qoceisf3d_cav"   long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1410 <field id="qlatisf3d_cav"   long_name="Ice shelf latent heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1411 <field id="qhcisf3d_cav"    long_name="Ice shelf heat content flux of injected water" unit="W/m2"     grid_ref="grid_T_3D" /> 
     1412 <field id="ttbl_cav"        long_name="temperature in Losch tbl"                      unit="degC"     /> 
     1413 <field id="isfthermald_cav" long_name="thermal driving of ice shelf melting"          unit="degC"     /> 
     1414 <field id="isfgammat"       long_name="Ice shelf heat-transfert velocity"             unit="m/s"      /> 
     1415 <field id="isfgammas"       long_name="Ice shelf salt-transfert velocity"             unit="m/s"      /> 
     1416 <field id="stbl"            long_name="salinity in the Losh tbl"                      unit="1e-3"     /> 
     1417 <field id="utbl"            long_name="zonal current in the Losh tbl at T point"      unit="m/s"      /> 
     1418 <field id="vtbl"            long_name="merid current in the Losh tbl at T point"      unit="m/s"      /> 
     1419 <field id="isfustar"        long_name="ustar at T point used in ice shelf melting"    unit="m/s"      /> 
     1420 <field id="qconisf"         long_name="Conductive heat flux through the ice shelf"    unit="W/m2"     /> 
     1421      \end{xmllines} 
     1422\end{description} 
     1423 
     1424%% ================================================================================================= 
     1425\subsection{Ice sheet coupling} 
     1426\label{subsec:ISF_iscpl} 
    13161427 
    13171428Ice sheet/ocean coupling is done through file exchange at the restart step. 
    1318 At each restart step: 
    1319  
    1320 \begin{enumerate} 
    1321 \item the ice sheet model send a new bathymetry and ice shelf draft netcdf file. 
    1322 \item a new domcfg.nc file is built using the DOMAINcfg tools. 
    1323 \item \NEMO\ run for a specific period and output the average melt rate over the period. 
    1324 \item the ice sheet model run using the melt rate outputed in step 4. 
    1325 \item go back to 1. 
    1326 \end{enumerate} 
    1327  
    1328 If \np[=.true.]{ln_iscpl}{ln\_iscpl}, the isf draft is assume to be different at each restart step with 
     1429At each restart step, the procedure is this one: 
     1430 
     1431\begin{description} 
     1432\item[Step 1]: the ice sheet model send a new bathymetry and ice shelf draft netcdf file. 
     1433\item[Step 2]: a new domcfg.nc file is built using the DOMAINcfg tools. 
     1434\item[Step 3]: NEMO run for a specific period and output the average melt rate over the period. 
     1435\item[Step 4]: the ice sheet model run using the melt rate outputed in step 3. 
     1436\item[Step 5]: go back to 1. 
     1437\end{description} 
     1438 
     1439If \np{ln_iscpl}{ln\_iscpl}\forcode{ = .true.}, the isf draft is assume to be different at each restart step with 
    13291440potentially some new wet/dry cells due to the ice sheet dynamics/thermodynamics. 
    1330 The wetting and drying scheme applied on the restart is very simple and described below for the 6 different possible cases: 
     1441The wetting and drying scheme, applied on the restart, is very simple. The 6 different possible cases for the tracer and ssh are: 
    13311442 
    13321443\begin{description} 
    1333 \item [Thin a cell down]: T/S/ssh are unchanged and U/V in the top cell are corrected to keep the barotropic transport (bt) constant 
    1334   ($bt_b=bt_n$). 
    1335 \item [Enlarge  a cell]: See case "Thin a cell down" 
    1336 \item [Dry a cell]: mask, T/S, U/V and ssh are set to 0. 
    1337   Furthermore, U/V into the water column are modified to satisfy ($bt_b=bt_n$). 
    1338 \item [Wet a cell]: mask is set to 1, T/S is extrapolated from neighbours, $ssh_n = ssh_b$ and U/V set to 0. 
    1339   If no neighbours, T/S is extrapolated from old top cell value. 
    1340   If no neighbours along i,j and k (both previous test failed), T/S/U/V/ssh and mask are set to 0. 
    1341 \item [Dry a column]: mask, T/S, U/V are set to 0 everywhere in the column and ssh set to 0. 
    1342 \item [Wet a column]: set mask to 1, T/S is extrapolated from neighbours, ssh is extrapolated from neighbours and U/V set to 0. 
    1343   If no neighbour, T/S/U/V and mask set to 0. 
     1444   \item[Thin a cell]: 
     1445   T/S/ssh are unchanged. 
     1446 
     1447   \item[Enlarge  a cell]: 
     1448   See case "Thin a cell down" 
     1449 
     1450   \item[Dry a cell]: 
     1451   Mask, T/S, U/V and ssh are set to 0. 
     1452 
     1453   \item[Wet a cell]:  
     1454   Mask is set to 1, T/S is extrapolated from neighbours, $ssh_n = ssh_b$. 
     1455   If no neighbours, T/S is extrapolated from old top cell value.  
     1456   If no neighbours along i,j and k (both previous tests failed), T/S/ssh and mask are set to 0. 
     1457 
     1458   \item[Dry a column]: 
     1459   mask, T/S and ssh are set to 0. 
     1460 
     1461   \item[Wet a column]: 
     1462   set mask to 1, T/S/ssh are extrapolated from neighbours. 
     1463   If no neighbour, T/S/ssh and mask set to 0. 
    13441464\end{description} 
     1465 
     1466The method described above will strongly affect the barotropic transport under an ice shelf when the geometry change. 
     1467In order to keep the model stable, an adjustment of the dynamics at the initialisation after the coupling step is needed.  
     1468The idea behind this is to keep $\pd[\eta]{t}$ as it should be without change in geometry at the initialisation.  
     1469This will prevent any strong velocity due to large pressure gradient.  
     1470To do so, we correct the horizontal divergence before $\pd[\eta]{t}$ is computed in the first time step.\\ 
    13451471 
    13461472Furthermore, as the before and now fields are not compatible (modification of the geometry), 
     
    13491475The horizontal extrapolation to fill new cell with realistic value is called \np{nn_drown}{nn\_drown} times. 
    13501476It means that if the grounding line retreat by more than \np{nn_drown}{nn\_drown} cells between 2 coupling steps, 
    1351 the code will be unable to fill all the new wet cells properly. 
     1477the code will be unable to fill all the new wet cells properly and the model is likely to blow up at the initialisation. 
    13521478The default number is set up for the MISOMIP idealised experiments. 
    13531479This coupling procedure is able to take into account grounding line and calving front migration. 
    1354 However, it is a non-conservative processe. 
     1480However, it is a non-conservative proccess.  
    13551481This could lead to a trend in heat/salt content and volume.\\ 
    13561482 
    13571483In order to remove the trend and keep the conservation level as close to 0 as possible, 
    1358 a simple conservation scheme is available with \np[=.true.]{ln_hsb}{ln\_hsb}. 
    1359 The heat/salt/vol. gain/loss is diagnosed, as well as the location. 
    1360 A correction increment is computed and apply each time step during the next \np{rn_fiscpl}{rn\_fiscpl} time steps. 
    1361 For safety, it is advised to set \np{rn_fiscpl}{rn\_fiscpl} equal to the coupling period (smallest increment possible). 
    1362 The corrective increment is apply into the cell itself (if it is a wet cell), the neigbouring cells or the closest wet cell (if the cell is now dry). 
     1484a simple conservation scheme is available with \np{ln_isfcpl_cons}{ln\_isfcpl\_cons}\forcode{ = .true.}. 
     1485The heat/salt/vol. gain/loss are diagnosed, as well as the location. 
     1486A correction increment is computed and applied each time step during the model run. 
     1487The corrective increment are applied into the cells itself (if it is a wet cell), the neigbouring cells or the closest wet cell (if the cell is now dry). 
    13631488 
    13641489%% ================================================================================================= 
     
    14091534Melt water (and other variables on the configuration grid) are written into the main \NEMO\ model output files. 
    14101535 
     1536By default, iceberg thermodynamic and dynamic are computed using ocean surface variable (sst, ssu, ssv) and the icebergs are not sensible to the bathymetry (only to land) whatever the iceberg draft.  
     1537\citet{Merino_OM2016} developed an option to use vertical profiles of ocean currents and temperature instead (\np{ln_M2016}{ln\_M2016}). 
     1538Full details on the sensitivity to this parameter in done in \citet{Merino_OM2016}.  
     1539If \np{ln_M2016}{ln\_M2016} activated, \np{ln_icb_grd}{ln\_icb\_grd} activate (or not) an option to prevent thick icebergs to move across shallow bank (ie shallower than the iceberg draft). 
     1540This option need to be used with care as it could required to either change the distribution to prevent generation of icebergs with draft larger than the bathymetry  
     1541or to build a variable \forcode{maxclass} to prevent NEMO filling the icebergs classes too thick for the local bathymetry. 
     1542 
    14111543Extensive diagnostics can be produced. 
    14121544Separate output files are maintained for human-readable iceberg information. 
     
    14651597Then using the routine \rou{sbcblk\_algo\_ncar} and starting from the neutral drag coefficent provided, 
    14661598the drag coefficient is computed according to the stable/unstable conditions of the 
    1467 air-sea interface following \citet{large.yeager_rpt04}. 
     1599air-sea interface following \citet{large.yeager_trpt04}. 
    14681600 
    14691601%% ================================================================================================= 
     
    15761708 
    15771709The surface stress felt by the ocean is the atmospheric stress minus the net stress going 
    1578 into the waves \citep{janssen.breivik.ea_rpt13}. Therefore, when waves are growing, momentum and energy is spent and is not 
     1710into the waves \citep{janssen.breivik.ea_trpt13}. Therefore, when waves are growing, momentum and energy is spent and is not 
    15791711available for forcing the mean circulation, while in the opposite case of a decaying sea 
    15801712state, more momentum is available for forcing the ocean. 
     
    17951927\label{subsec:SBC_fwb} 
    17961928 
    1797 For global ocean simulation, it can be useful to introduce a control of the mean sea level in order to 
    1798 prevent unrealistic drift of the sea surface height due to inaccuracy in the freshwater fluxes. 
    1799 In \NEMO, two way of controlling the freshwater budget are proposed: 
     1929\begin{listing} 
     1930  \nlst{namsbc_fwb} 
     1931  \caption{\forcode{&namsbc_fwb}} 
     1932  \label{lst:namsbc_fwb} 
     1933\end{listing} 
     1934 
     1935For global ocean simulations, it can be useful to introduce a control of the 
     1936mean sea level in order to prevent unrealistic drifting of the sea surface 
     1937height due to unbalanced freshwater fluxes. In \NEMO, two options for 
     1938controlling the freshwater budget are proposed. 
    18001939 
    18011940\begin{description} 
    1802 \item [{\np[=0]{nn_fwb}{nn\_fwb}}] no control at all. 
    1803   The mean sea level is free to drift, and will certainly do so. 
    1804 \item [{\np[=1]{nn_fwb}{nn\_fwb}}] global mean \textit{emp} set to zero at each model time step. 
     1941\item [{\np[=0]{nn_fwb}{nn\_fwb}}:] No control at all; the mean sea level is 
     1942  free to drift, and will certainly do so. 
     1943\item [{\np[=1]{nn_fwb}{nn\_fwb}}:] The global mean \textit{emp} is set to zero at each model time step. 
    18051944  %GS: comment below still relevant ? 
    18061945  %Note that with a sea-ice model, this technique only controls the mean sea level with linear free surface and no mass flux between ocean and ice (as it is implemented in the current ice-ocean coupling). 
    1807 \item [{\np[=2]{nn_fwb}{nn\_fwb}}] freshwater budget is adjusted from the previous year annual mean budget which 
    1808   is read in the \textit{EMPave\_old.dat} file. 
    1809   As the model uses the Boussinesq approximation, the annual mean fresh water budget is simply evaluated from 
    1810   the change in the mean sea level at January the first and saved in the \textit{EMPav.dat} file. 
     1946\item [{\np[=2]{nn_fwb}{nn\_fwb}}:] \textit{emp} is adjusted by adding a 
     1947  spatially uniform, annual-mean freshwater flux that balances the freshwater 
     1948  budget at the end of the previous year; as the model uses the Boussinesq 
     1949  approximation, the freshwater budget can be evaluated from the change in the 
     1950  mean sea level and in the ice and snow mass after the end of each simulation 
     1951  year; at the start of the model run, an initial adjustment flux can be set 
     1952  using parameter \np{rn_rwb0}{rn\_fwb0} in namelist \nam{sbc_fwb}{sbc\_fwb}. 
    18111953\end{description} 
    18121954 
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