Changeset 9393 for branches/2017/dev_merge_2017/DOC/tex_sub/chap_SBC.tex
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branches/2017/dev_merge_2017/DOC/tex_sub/chap_SBC.tex
r9392 r9393 28 28 29 29 Five different ways to provide the first six fields to the ocean are available which 30 are controlled by namelist \ngn{namsbc} variables: an analytical formulation (\np{ln _ana}~=~true),31 a flux formulation (\np{ln _flx}~=~true), a bulk formulae formulation (CORE32 (\np{ln _blk_core}~=~true), CLIO (\np{ln_blk_clio}~=~true) or MFS30 are controlled by namelist \ngn{namsbc} variables: an analytical formulation (\np{ln\_ana}\forcode{ = .true.}), 31 a flux formulation (\np{ln\_flx}\forcode{ = .true.}), a bulk formulae formulation (CORE 32 (\np{ln\_blk\_core}\forcode{ = .true.}), CLIO (\np{ln\_blk\_clio}\forcode{ = .true.}) or MFS 33 33 \footnote { Note that MFS bulk formulae compute fluxes only for the ocean component} 34 (\np{ln _blk_mfs}~=~true) bulk formulae) and a coupled or mixed forced/coupled formulation35 (exchanges with a atmospheric model via the OASIS coupler) (\np{ln _cpl} or \np{ln_mixcpl}~=~true).36 When used ($i.e.$ \np{ln _apr_dyn}~=~true), the atmospheric pressure forces both ocean and ice dynamics.37 38 The frequency at which the forcing fields have to be updated is given by the \np{nn _fsbc} namelist parameter.34 (\np{ln\_blk\_mfs}\forcode{ = .true.}) bulk formulae) and a coupled or mixed forced/coupled formulation 35 (exchanges with a atmospheric model via the OASIS coupler) (\np{ln\_cpl} or \np{ln\_mixcpl}\forcode{ = .true.}). 36 When used ($i.e.$ \np{ln\_apr\_dyn}\forcode{ = .true.}), the atmospheric pressure forces both ocean and ice dynamics. 37 38 The frequency at which the forcing fields have to be updated is given by the \np{nn\_fsbc} namelist parameter. 39 39 When the fields are supplied from data files (flux and bulk formulations), the input fields 40 40 need not be supplied on the model grid. Instead a file of coordinates and weights can … … 50 50 \item the rotation of vector components supplied relative to an east-north 51 51 coordinate system onto the local grid directions in the model ; 52 \item the addition of a surface restoring term to observed SST and/or SSS (\np{ln _ssr}~=~true) ;53 \item the modification of fluxes below ice-covered areas (using observed ice-cover or a sea-ice model) (\np{nn _ice}~=~0,1, 2 or 3) ;54 \item the addition of river runoffs as surface freshwater fluxes or lateral inflow (\np{ln _rnf}~=~true) ;55 \item the addition of isf melting as lateral inflow (parameterisation) or as fluxes applied at the land-ice ocean interface (\np{ln _isf}) ;56 \item the addition of a freshwater flux adjustment in order to avoid a mean sea-level drift (\np{nn _fwb}~=~0,~1~or~2) ;57 \item the transformation of the solar radiation (if provided as daily mean) into a diurnal cycle (\np{ln _dm2dc}~=~true) ;58 and a neutral drag coefficient can be read from an external wave model (\np{ln _cdgw}~=~true).52 \item the addition of a surface restoring term to observed SST and/or SSS (\np{ln\_ssr}\forcode{ = .true.}) ; 53 \item the modification of fluxes below ice-covered areas (using observed ice-cover or a sea-ice model) (\np{nn\_ice}\forcode{ = 0..3}) ; 54 \item the addition of river runoffs as surface freshwater fluxes or lateral inflow (\np{ln\_rnf}\forcode{ = .true.}) ; 55 \item the addition of isf melting as lateral inflow (parameterisation) or as fluxes applied at the land-ice ocean interface (\np{ln\_isf}) ; 56 \item the addition of a freshwater flux adjustment in order to avoid a mean sea-level drift (\np{nn\_fwb}\forcode{ = 0..2}) ; 57 \item the transformation of the solar radiation (if provided as daily mean) into a diurnal cycle (\np{ln\_dm2dc}\forcode{ = .true.}) ; 58 and a neutral drag coefficient can be read from an external wave model (\np{ln\_cdgw}\forcode{ = .true.}). 59 59 \end{itemize} 60 60 The latter option is possible only in case core or mfs bulk formulas are selected. … … 91 91 and \eqref{Eq_tra_sbc_lin} in \S\ref{TRA_sbc}). 92 92 The latter is the penetrative part of the heat flux. It is applied as a 3D 93 trends of the temperature equation (\mdl{traqsr} module) when \np{ln _traqsr}=\textit{true}.93 trends of the temperature equation (\mdl{traqsr} module) when \np{ln\_traqsr}\forcode{ = .true.}. 94 94 The way the light penetrates inside the water column is generally a sum of decreasing 95 95 exponentials (see \S\ref{TRA_qsr}). … … 110 110 %created!) 111 111 % 112 %Especially the \np{nn _fsbc}, the \mdl{sbc\_oce} module (fluxes + mean sst sss ssu112 %Especially the \np{nn\_fsbc}, the \mdl{sbc\_oce} module (fluxes + mean sst sss ssu 113 113 %ssv) i.e. information required by flux computation or sea-ice 114 114 % … … 130 130 The ocean model provides, at each time step, to the surface module (\mdl{sbcmod}) 131 131 the surface currents, temperature and salinity. 132 These variables are averaged over \np{nn _fsbc} time-step (\ref{Tab_ssm}),132 These variables are averaged over \np{nn\_fsbc} time-step (\ref{Tab_ssm}), 133 133 and it is these averaged fields which are used to computes the surface fluxes 134 at a frequency of \np{nn _fsbc} time-step.134 at a frequency of \np{nn\_fsbc} time-step. 135 135 136 136 … … 157 157 % Input Data 158 158 % ================================================================ 159 \section{Input Data generic interface}159 \section{Input data generic interface} 160 160 \label{SBC_input} 161 161 … … 185 185 186 186 Note that when an input data is archived on a disc which is accessible directly 187 from the workspace where the code is executed, then the use can set the \np{cn _dir}187 from the workspace where the code is executed, then the use can set the \np{cn\_dir} 188 188 to the pathway leading to the data. By default, the data are assumed to have been 189 189 copied so that cn\_dir='./'. … … 192 192 % Input Data specification (\mdl{fldread}) 193 193 % ------------------------------------------------------------------------------------------------------------- 194 \subsection{Input Data specification (\protect\mdl{fldread})}194 \subsection{Input data specification (\protect\mdl{fldread})} 195 195 \label{SBC_fldread} 196 196 … … 214 214 \hline 215 215 & daily or weekLLL & monthly & yearly \\ \hline 216 clim = false & \ifile{fn\_yYYYYmMMdDD} & \ifile{fn\_yYYYYmMM} & \ifile{fn\_yYYYY}\\ \hline217 clim = true & not possible & \ifile{fn\_m??}& fn \\ \hline216 \np{clim}\forcode{ = .false.} & fn\_yYYYYmMMdDD.nc & fn\_yYYYYmMM.nc & fn\_yYYYY.nc \\ \hline 217 \np{clim}\forcode{ = .true.} & not possible & fn\_m??.nc & fn \\ \hline 218 218 \end{tabular} 219 219 \end{center} … … 271 271 a time interpolation will be performed at the following time: 0h30'00", 1h30'00", 2h30'00", etc. 272 272 However, for forcing data related to the surface module, values are not needed at every 273 time-step but at every \np{nn _fsbc} time-step. For example with \np{nn_fsbc}~=~3,273 time-step but at every \np{nn\_fsbc} time-step. For example with \np{nn\_fsbc}\forcode{ = 3}, 274 274 the surface module will be called at time-steps 1, 4, 7, etc. The date used for the time interpolation 275 is thus redefined to be at the middle of \np{nn _fsbc} time-step period. In the previous example,275 is thus redefined to be at the middle of \np{nn\_fsbc} time-step period. In the previous example, 276 276 this leads to: 1h30'00", 4h30'00", 7h30'00", etc. \\ 277 277 (2) For code readablility and maintenance issues, we don't take into account the NetCDF input file … … 300 300 % Interpolation on the Fly 301 301 % ------------------------------------------------------------------------------------------------------------- 302 \subsection [Interpolation on-the-Fly] {Interpolation on-the-Fly}302 \subsection{Interpolation on-the-fly} 303 303 \label{SBC_iof} 304 304 … … 324 324 Note that nn\_lsm=0 forces the code to not apply the procedure even if a file for land/sea mask is supplied. 325 325 326 \subsubsection{Bilinear Interpolation}326 \subsubsection{Bilinear interpolation} 327 327 \label{SBC_iof_bilinear} 328 328 … … 346 346 and wgt(1) corresponds to variable "wgt01" for example. 347 347 348 \subsubsection{Bicubic Interpolation}348 \subsubsection{Bicubic interpolation} 349 349 \label{SBC_iof_bicubic} 350 350 … … 421 421 % Standalone Surface Boundary Condition Scheme 422 422 % ------------------------------------------------------------------------------------------------------------- 423 \subsection [Standalone Surface Boundary Condition Scheme] {Standalone Surface Boundary Condition Scheme}423 \subsection{Standalone surface boundary condition scheme} 424 424 \label{SAS_iof} 425 425 … … 438 438 \item Development of sea-ice algorithms or parameterizations. 439 439 \item spinup of the iceberg floats 440 \item ocean/sea-ice simulation with both media running in parallel (\np{ln _mixcpl}~=~\textit{true})440 \item ocean/sea-ice simulation with both media running in parallel (\np{ln\_mixcpl}\forcode{ = .true.}) 441 441 \end{itemize} 442 442 … … 481 481 % Analytical formulation (sbcana module) 482 482 % ================================================================ 483 \section [Analytical formulation (\textit{sbcana}) ] 484 {Analytical formulation (\protect\mdl{sbcana} module) } 483 \section{Analytical formulation (\protect\mdl{sbcana})} 485 484 \label{SBC_ana} 486 485 … … 492 491 In this case, all the six fluxes needed by the ocean are assumed to 493 492 be uniform in space. They take constant values given in the namelist 494 \ngn{namsbc{\_}ana} by the variables \np{rn _utau0}, \np{rn_vtau0}, \np{rn_qns0},495 \np{rn _qsr0}, and \np{rn_emp0} ($\textit{emp}=\textit{emp}_S$). The runoff is set to zero.493 \ngn{namsbc{\_}ana} by the variables \np{rn\_utau0}, \np{rn\_vtau0}, \np{rn\_qns0}, 494 \np{rn\_qsr0}, and \np{rn\_emp0} ($\textit{emp}=\textit{emp}_S$). The runoff is set to zero. 496 495 In addition, the wind is allowed to reach its nominal value within a given number 497 of time steps (\np{nn _tau000}).496 of time steps (\np{nn\_tau000}). 498 497 499 498 If a user wants to apply a different analytical forcing, the \mdl{sbcana} … … 506 505 % Flux formulation 507 506 % ================================================================ 508 \section [Flux formulation (\textit{sbcflx}) ] 509 {Flux formulation (\protect\mdl{sbcflx} module) } 507 \section{Flux formulation (\protect\mdl{sbcflx})} 510 508 \label{SBC_flx} 511 509 %------------------------------------------namsbc_flx---------------------------------------------------- … … 513 511 %------------------------------------------------------------------------------------------------------------- 514 512 515 In the flux formulation (\ forcode{ln_flx= .true.}), the surface boundary513 In the flux formulation (\np{ln\_flx}\forcode{ = .true.}), the surface boundary 516 514 condition fields are directly read from input files. The user has to define 517 515 in the namelist \ngn{namsbc{\_}flx} the name of the file, the name of the variable … … 528 526 % Bulk formulation 529 527 % ================================================================ 530 \section [Bulk formulation (\textit{sbcblk\_core}, \textit{sbcblk\_clio} or \textit{sbcblk\_mfs})]531 {Bulk formulation \small{(\protect\mdl{sbcblk\_core} \protect\mdl{sbcblk\_clio} \protect\mdl{sbcblk\_mfs} modules)}}528 \section[Bulk formulation {(\textit{sbcblk\{\_core,\_clio,\_mfs\}.F90})}] 529 {Bulk formulation {(\protect\mdl{sbcblk\_core}, \protect\mdl{sbcblk\_clio}, \protect\mdl{sbcblk\_mfs})}} 532 530 \label{SBC_blk} 533 531 … … 537 535 The atmospheric fields used depend on the bulk formulae used. Three bulk formulations 538 536 are available : the CORE, the CLIO and the MFS bulk formulea. The choice is made by setting to true 539 one of the following namelist variable : \np{ln _core} ; \np{ln_clio} or \np{ln_mfs}.537 one of the following namelist variable : \np{ln\_core} ; \np{ln\_clio} or \np{ln\_mfs}. 540 538 541 539 Note : in forced mode, when a sea-ice model is used, a bulk formulation (CLIO or CORE) have to be used. … … 546 544 % CORE Bulk formulea 547 545 % ------------------------------------------------------------------------------------------------------------- 548 \subsection [CORE Bulk formulea (\protect\forcode{ln_core = .true.})] 549 {CORE Bulk formulea (\protect\forcode{ln_core = .true.}, \protect\mdl{sbcblk\_core})} 546 \subsection{CORE formulea (\protect\mdl{sbcblk\_core}, \protect\np{ln\_core}\forcode{ = .true.})} 550 547 \label{SBC_blk_core} 551 548 %------------------------------------------namsbc_core---------------------------------------------------- … … 592 589 or larger than the one of the input atmospheric fields. 593 590 594 The \np{sn _wndi}, \np{sn_wndj}, \np{sn_qsr}, \np{sn_qlw}, \np{sn_tair}, \np{sn_humi},595 \np{sn _prec}, \np{sn_snow}, \np{sn_tdif} parameters describe the fields591 The \np{sn\_wndi}, \np{sn\_wndj}, \np{sn\_qsr}, \np{sn\_qlw}, \np{sn\_tair}, \np{sn\_humi}, 592 \np{sn\_prec}, \np{sn\_snow}, \np{sn\_tdif} parameters describe the fields 596 593 and the way they have to be used (spatial and temporal interpolations). 597 594 598 \np{cn _dir} is the directory of location of bulk files599 \np{ln _taudif} is the flag to specify if we use Hight Frequency (HF) tau information (.true.) or not (.false.)600 \np{rn _zqt}: is the height of humidity and temperature measurements (m)601 \np{rn _zu}: is the height of wind measurements (m)595 \np{cn\_dir} is the directory of location of bulk files 596 \np{ln\_taudif} is the flag to specify if we use Hight Frequency (HF) tau information (.true.) or not (.false.) 597 \np{rn\_zqt}: is the height of humidity and temperature measurements (m) 598 \np{rn\_zu}: is the height of wind measurements (m) 602 599 603 600 Three multiplicative factors are availables : 604 \np{rn _pfac} and \np{rn_efac} allows to adjust (if necessary) the global freshwater budget601 \np{rn\_pfac} and \np{rn\_efac} allows to adjust (if necessary) the global freshwater budget 605 602 by increasing/reducing the precipitations (total and snow) and or evaporation, respectively. 606 The third one,\np{rn _vfac}, control to which extend the ice/ocean velocities are taken into account603 The third one,\np{rn\_vfac}, control to which extend the ice/ocean velocities are taken into account 607 604 in the calculation of surface wind stress. Its range should be between zero and one, 608 605 and it is recommended to set it to 0. … … 611 608 % CLIO Bulk formulea 612 609 % ------------------------------------------------------------------------------------------------------------- 613 \subsection [CLIO Bulk formulea (\protect\forcode{ln_clio = .true.})] 614 {CLIO Bulk formulea (\protect\forcode{ln_clio = .true.}, \protect\mdl{sbcblk\_clio})} 610 \subsection{CLIO formulea (\protect\mdl{sbcblk\_clio}, \protect\np{ln\_clio}\forcode{ = .true.})} 615 611 \label{SBC_blk_clio} 616 612 %------------------------------------------namsbc_clio---------------------------------------------------- … … 652 648 % MFS Bulk formulae 653 649 % ------------------------------------------------------------------------------------------------------------- 654 \subsection [MFS Bulk formulea (\protect\forcode{ln_mfs = .true.})] 655 {MFS Bulk formulea (\protect\forcode{ln_mfs = .true.}, \protect\mdl{sbcblk\_mfs})} 650 \subsection{MFS formulea (\protect\mdl{sbcblk\_mfs}, \protect\np{ln\_mfs}\forcode{ = .true.})} 656 651 \label{SBC_blk_mfs} 657 652 %------------------------------------------namsbc_mfs---------------------------------------------------- … … 679 674 The required 7 input fields must be provided on the model Grid-T and are: 680 675 \begin{itemize} 681 \item Zonal Component of the 10m wind ($ms^{-1}$) (\np{sn _windi})682 \item Meridional Component of the 10m wind ($ms^{-1}$) (\np{sn _windj})683 \item Total Claud Cover (\%) (\np{sn _clc})684 \item 2m Air Temperature ($K$) (\np{sn _tair})685 \item 2m Dew Point Temperature ($K$) (\np{sn _rhm})686 \item Total Precipitation ${Kg} m^{-2} s^{-1}$ (\np{sn _prec})687 \item Mean Sea Level Pressure (${Pa}$) (\np{sn _msl})676 \item Zonal Component of the 10m wind ($ms^{-1}$) (\np{sn\_windi}) 677 \item Meridional Component of the 10m wind ($ms^{-1}$) (\np{sn\_windj}) 678 \item Total Claud Cover (\%) (\np{sn\_clc}) 679 \item 2m Air Temperature ($K$) (\np{sn\_tair}) 680 \item 2m Dew Point Temperature ($K$) (\np{sn\_rhm}) 681 \item Total Precipitation ${Kg} m^{-2} s^{-1}$ (\np{sn\_prec}) 682 \item Mean Sea Level Pressure (${Pa}$) (\np{sn\_msl}) 688 683 \end{itemize} 689 684 % ------------------------------------------------------------------------------------------------------------- … … 691 686 % Coupled formulation 692 687 % ================================================================ 693 \section [Coupled formulation (\textit{sbccpl}) ] 694 {Coupled formulation (\protect\mdl{sbccpl} module)} 688 \section{Coupled formulation (\protect\mdl{sbccpl})} 695 689 \label{SBC_cpl} 696 690 %------------------------------------------namsbc_cpl---------------------------------------------------- … … 709 703 as well as to \href{http://wrf-model.org/}{WRF} (Weather Research and Forecasting Model). 710 704 711 Note that in addition to the setting of \np{ln _cpl} to true, the \key{coupled} have to be defined.705 Note that in addition to the setting of \np{ln\_cpl} to true, the \key{coupled} have to be defined. 712 706 The CPP key is mainly used in sea-ice to ensure that the atmospheric fluxes are 713 707 actually recieved by the ice-ocean system (no calculation of ice sublimation in coupled mode). … … 730 724 % Atmospheric pressure 731 725 % ================================================================ 732 \section [Atmospheric pressure (\textit{sbcapr})] 733 {Atmospheric pressure (\protect\mdl{sbcapr})} 726 \section{Atmospheric pressure (\protect\mdl{sbcapr})} 734 727 \label{SBC_apr} 735 728 %------------------------------------------namsbc_apr---------------------------------------------------- … … 738 731 739 732 The optional atmospheric pressure can be used to force ocean and ice dynamics 740 (\np{ln _apr_dyn}~=~true, \textit{\ngn{namsbc}} namelist ).741 The input atmospheric forcing defined via \np{sn _apr} structure (\textit{namsbc\_apr} namelist)733 (\np{ln\_apr\_dyn}\forcode{ = .true.}, \textit{\ngn{namsbc}} namelist ). 734 The input atmospheric forcing defined via \np{sn\_apr} structure (\textit{namsbc\_apr} namelist) 742 735 can be interpolated in time to the model time step, and even in space when the 743 736 interpolation on-the-fly is used. When used to force the dynamics, the atmospheric … … 748 741 \end{equation} 749 742 where $P_{atm}$ is the atmospheric pressure and $P_o$ a reference atmospheric pressure. 750 A value of $101,000~N/m^2$ is used unless \np{ln _ref_apr} is set to true. In this case $P_o$743 A value of $101,000~N/m^2$ is used unless \np{ln\_ref\_apr} is set to true. In this case $P_o$ 751 744 is set to the value of $P_{atm}$ averaged over the ocean domain, $i.e.$ the mean value of 752 745 $\eta_{ib}$ is kept to zero at all time step. … … 760 753 When using time-splitting and BDY package for open boundaries conditions, the equivalent 761 754 inverse barometer sea surface height $\eta_{ib}$ can be added to BDY ssh data: 762 \np{ln _apr_obc} might be set to true.755 \np{ln\_apr\_obc} might be set to true. 763 756 764 757 % ================================================================ 765 758 % Tidal Potential 766 759 % ================================================================ 767 \section [Tidal Potential (\textit{sbctide})] 768 {Tidal Potential (\protect\mdl{sbctide})} 760 \section{Tidal potential (\protect\mdl{sbctide})} 769 761 \label{SBC_tide} 770 762 … … 774 766 775 767 A module is available to compute the tidal potential and use it in the momentum equation. 776 This option is activated when \np{ln _tide} is set to true in \ngn{nam\_tide}.768 This option is activated when \np{ln\_tide} is set to true in \ngn{nam\_tide}. 777 769 778 770 Some parameters are available in namelist \ngn{nam\_tide}: 779 771 780 - \np{ln _tide_load} activate the load potential forcing and \np{filetide_load} is the associated file781 782 - \np{ln _tide_pot} activate the tidal potential forcing783 784 - \np{nb _harmo} is the number of constituent used772 - \np{ln\_tide\_load} activate the load potential forcing and \np{filetide\_load} is the associated file 773 774 - \np{ln\_tide\_pot} activate the tidal potential forcing 775 776 - \np{nb\_harmo} is the number of constituent used 785 777 786 778 - \np{clname} is the name of constituent … … 821 813 % River runoffs 822 814 % ================================================================ 823 \section [River runoffs (\textit{sbcrnf})] 824 {River runoffs (\protect\mdl{sbcrnf})} 815 \section{River runoffs (\protect\mdl{sbcrnf})} 825 816 \label{SBC_rnf} 826 817 %------------------------------------------namsbc_rnf---------------------------------------------------- … … 863 854 depth (in metres) which the river should be added to. 864 855 865 Namelist variables in \ngn{namsbc\_rnf}, \np{ln _rnf_depth}, \np{ln_rnf_sal} and \np{ln_rnf_temp} control whether856 Namelist variables in \ngn{namsbc\_rnf}, \np{ln\_rnf\_depth}, \np{ln\_rnf\_sal} and \np{ln\_rnf\_temp} control whether 866 857 the river attributes (depth, salinity and temperature) are read in and used. If these are set 867 858 as false the river is added to the surface box only, assumed to be fresh (0~psu), and/or … … 876 867 to give the heat and salt content of the river runoff. 877 868 After the user specified depth is read ini, the number of grid boxes this corresponds to is 878 calculated and stored in the variable \np{nz _rnf}.869 calculated and stored in the variable \np{nz\_rnf}. 879 870 The variable \textit{h\_dep} is then calculated to be the depth (in metres) of the bottom of the 880 871 lowest box the river water is being added to (i.e. the total depth that river water is being added to in the model). … … 937 928 % Ice shelf melting 938 929 % ================================================================ 939 \section [Ice shelf melting (\textit{sbcisf})] 940 {Ice shelf melting (\protect\mdl{sbcisf})} 930 \section{Ice shelf melting (\protect\mdl{sbcisf})} 941 931 \label{SBC_isf} 942 932 %------------------------------------------namsbc_isf---------------------------------------------------- 943 933 \forfile{../namelists/namsbc_isf} 944 934 %-------------------------------------------------------------------------------------------------------- 945 Namelist variable in \ngn{namsbc}, \np{nn _isf}, controls the ice shelf representation used.935 Namelist variable in \ngn{namsbc}, \np{nn\_isf}, controls the ice shelf representation used. 946 936 \begin{description} 947 \item[\np{nn _isf}~=~1]948 The ice shelf cavity is represented (\np{ln _isfcav}~=~trueneeded). The fwf and heat flux are computed.937 \item[\np{nn\_isf}\forcode{ = 1}] 938 The ice shelf cavity is represented (\np{ln\_isfcav}\forcode{ = .true.} needed). The fwf and heat flux are computed. 949 939 Two different bulk formula are available: 950 940 \begin{description} 951 \item[\np{nn _isfblk}~=~1]941 \item[\np{nn\_isfblk}\forcode{ = 1}] 952 942 The bulk formula used to compute the melt is based the one described in \citet{Hunter2006}. 953 943 This formulation is based on a balance between the upward ocean heat flux and the latent heat flux at the ice shelf base. 954 944 955 \item[\np{nn _isfblk}~=~2]945 \item[\np{nn\_isfblk}\forcode{ = 2}] 956 946 The bulk formula used to compute the melt is based the one described in \citet{Jenkins1991}. 957 947 This formulation is based on a 3 equations formulation (a heat flux budget, a salt flux budget … … 961 951 For this 2 bulk formulations, there are 3 different ways to compute the exchange coeficient: 962 952 \begin{description} 963 \item[\np{nn\_gammablk ~=~0~}]964 The salt and heat exchange coefficients are constant and defined by \np{rn _gammas0} and \np{rn_gammat0}965 966 \item[\np{nn\_gammablk ~=~1~}]967 The salt and heat exchange coefficients are velocity dependent and defined as $rn\_gammas0 \times u_{*}$ and $rn\_gammat0\times u_{*}$968 where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn _hisf_tbl} meters).953 \item[\np{nn\_gammablk}\forcode{ = 0}] 954 The salt and heat exchange coefficients are constant and defined by \np{rn\_gammas0} and \np{rn\_gammat0} 955 956 \item[\np{nn\_gammablk}\forcode{ = 1}] 957 The salt and heat exchange coefficients are velocity dependent and defined as \np{rn\_gammas0}$ \times u_{*}$ and \np{rn\_gammat0}$ \times u_{*}$ 958 where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn\_hisf\_tbl} meters). 969 959 See \citet{Jenkins2010} for all the details on this formulation. 970 960 971 \item[\np{nn\_gammablk ~=~2~}]961 \item[\np{nn\_gammablk}\forcode{ = 2}] 972 962 The salt and heat exchange coefficients are velocity and stability dependent and defined as 973 963 $\gamma_{T,S} = \frac{u_{*}}{\Gamma_{Turb} + \Gamma^{T,S}_{Mole}}$ 974 where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn _hisf_tbl} meters),964 where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn\_hisf\_tbl} meters), 975 965 $\Gamma_{Turb}$ the contribution of the ocean stability and 976 966 $\Gamma^{T,S}_{Mole}$ the contribution of the molecular diffusion. … … 978 968 \end{description} 979 969 980 \item[\np{nn _isf}~=~2]970 \item[\np{nn\_isf}\forcode{ = 2}] 981 971 A parameterisation of isf is used. The ice shelf cavity is not represented. 982 972 The fwf is distributed along the ice shelf edge between the depth of the average grounding line (GL) 983 (\np{sn _depmax_isf}) and the base of the ice shelf along the calving front (\np{sn_depmin_isf}) as in (\np{nn_isf}~=~3).973 (\np{sn\_depmax\_isf}) and the base of the ice shelf along the calving front (\np{sn\_depmin\_isf}) as in (\np{nn\_isf}\forcode{ = 3}). 984 974 Furthermore the fwf and heat flux are computed using the \citet{Beckmann2003} parameterisation of isf melting. 985 The effective melting length (\np{sn _Leff_isf}) is read from a file.986 987 \item[\np{nn _isf}~=~3]975 The effective melting length (\np{sn\_Leff\_isf}) is read from a file. 976 977 \item[\np{nn\_isf}\forcode{ = 3}] 988 978 A simple parameterisation of isf is used. The ice shelf cavity is not represented. 989 The fwf (\np{sn _rnfisf}) is prescribed and distributed along the ice shelf edge between the depth of the average grounding line (GL)990 (\np{sn _depmax_isf}) and the base of the ice shelf along the calving front (\np{sn_depmin_isf}).979 The fwf (\np{sn\_rnfisf}) is prescribed and distributed along the ice shelf edge between the depth of the average grounding line (GL) 980 (\np{sn\_depmax\_isf}) and the base of the ice shelf along the calving front (\np{sn\_depmin\_isf}). 991 981 The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 992 982 993 \item[\np{nn _isf}~=~4]994 The ice shelf cavity is opened (\np{ln _isfcav}~=~true needed). However, the fwf is not computed but specified from file \np{sn_fwfisf}).983 \item[\np{nn\_isf}\forcode{ = 4}] 984 The ice shelf cavity is opened (\np{ln\_isfcav}\forcode{ = .true.} needed). However, the fwf is not computed but specified from file \np{sn\_fwfisf}). 995 985 The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$.\\ 996 986 \end{description} 997 987 998 988 999 $\bullet$ \np{nn _isf}~=~1 and \np{nn_isf}~=~2compute a melt rate based on the water mass properties, ocean velocities and depth.989 $\bullet$ \np{nn\_isf}\forcode{ = 1} and \np{nn\_isf}\forcode{ = 2} compute a melt rate based on the water mass properties, ocean velocities and depth. 1000 990 This flux is thus highly dependent of the model resolution (horizontal and vertical), realism of the water masses onto the shelf ...\\ 1001 991 1002 992 1003 $\bullet$ \np{nn _isf}~=~3 and \np{nn_isf}~=~4read the melt rate from a file. You have total control of the fwf forcing.993 $\bullet$ \np{nn\_isf}\forcode{ = 3} and \np{nn\_isf}\forcode{ = 4} read the melt rate from a file. You have total control of the fwf forcing. 1004 994 This can be usefull if the water masses on the shelf are not realistic or the resolution (horizontal/vertical) are too 1005 995 coarse to have realistic melting or for studies where you need to control your heat and fw input.\\ 1006 996 1007 997 A namelist parameters control over how many meters the heat and fw fluxes are spread. 1008 \np{rn _hisf_tbl}] is the top boundary layer thickness as defined in \citet{Losch2008}.1009 This parameter is only used if \np{nn _isf}~=~1 or \np{nn_isf}~=~41010 1011 If \np{rn _hisf_tbl} = 0., the fluxes are put in the top level whatever is its tickness.1012 1013 If \np{rn _hisf_tbl} $>$ 0., the fluxes are spread over the first \np{rn_hisf_tbl} m (ie over one or several cells).\\998 \np{rn\_hisf\_tbl}] is the top boundary layer thickness as defined in \citet{Losch2008}. 999 This parameter is only used if \np{nn\_isf}\forcode{ = 1} or \np{nn\_isf}\forcode{ = 4} 1000 1001 If \np{rn\_hisf\_tbl}\forcode{ = 0}., the fluxes are put in the top level whatever is its tickness. 1002 1003 If \np{rn\_hisf\_tbl} $>$ 0., the fluxes are spread over the first \np{rn\_hisf\_tbl} m (ie over one or several cells).\\ 1014 1004 1015 1005 The ice shelf melt is implemented as a volume flux with in the same way as for the runoff. … … 1019 1009 1020 1010 1021 \section{ 1011 \section{Ice sheet coupling} 1022 1012 \label{SBC_iscpl} 1023 1013 %------------------------------------------namsbc_iscpl---------------------------------------------------- … … 1026 1016 Ice sheet/ocean coupling is done through file exchange at the restart step. NEMO, at each restart step, 1027 1017 read the bathymetry and ice shelf draft variable in a netcdf file. 1028 If \np{ln\_iscpl = ~true}, the isf draft is assume to be different at each restart step1018 If \np{ln\_iscpl}\forcode{ = .true.}, the isf draft is assume to be different at each restart step 1029 1019 with potentially some new wet/dry cells due to the ice sheet dynamics/thermodynamics. 1030 1020 The wetting and drying scheme applied on the restart is very simple and described below for the 6 different cases: … … 1043 1033 set mask to 1, T/S is extrapolated from neighbours, ssh is extrapolated from neighbours and U/V set to 0. If no neighbour, T/S/U/V and mask set to 0. 1044 1034 \end{description} 1045 The extrapolation is call \np{nn _drown} times. It means that if the grounding line retreat by more than \np{nn_drown} cells between 2 coupling steps,1035 The extrapolation is call \np{nn\_drown} times. It means that if the grounding line retreat by more than \np{nn\_drown} cells between 2 coupling steps, 1046 1036 the code will be unable to fill all the new wet cells properly. The default number is set up for the MISOMIP idealised experiments.\\ 1047 1037 This coupling procedure is able to take into account grounding line and calving front migration. However, it is a non-conservative processe. 1048 1038 This could lead to a trend in heat/salt content and volume. In order to remove the trend and keep the conservation level as close to 0 as possible, 1049 a simple conservation scheme is available with \np{ln\_hsb = ~true}. The heat/salt/vol. gain/loss is diagnose, as well as the location.1039 a simple conservation scheme is available with \np{ln\_hsb}\forcode{ = .true.}. The heat/salt/vol. gain/loss is diagnose, as well as the location. 1050 1040 Based on what is done on sbcrnf to prescribed a source of heat/salt/vol., the heat/salt/vol. gain/loss is removed/added, 1051 over a period of \np{rn _fiscpl} time step, into the system.1052 So after \np{rn _fiscpl} time step, all the heat/salt/vol. gain/loss due to extrapolation process is canceled.\\1041 over a period of \np{rn\_fiscpl} time step, into the system. 1042 So after \np{rn\_fiscpl} time step, all the heat/salt/vol. gain/loss due to extrapolation process is canceled.\\ 1053 1043 1054 1044 As the before and now fields are not compatible (modification of the geometry), the restart time step is prescribed to be an euler time step instead of a leap frog and $fields_b = fields_n$. … … 1068 1058 Icebergs are initially spawned into one of ten classes which have specific mass and thickness as described 1069 1059 in the \ngn{namberg} namelist: 1070 \np{rn _initial_mass} and \np{rn_initial_thickness}.1071 Each class has an associated scaling (\np{rn _mass_scaling}), which is an integer representing how many icebergs1060 \np{rn\_initial\_mass} and \np{rn\_initial\_thickness}. 1061 Each class has an associated scaling (\np{rn\_mass\_scaling}), which is an integer representing how many icebergs 1072 1062 of this class are being described as one lagrangian point (this reduces the numerical problem of tracking every single iceberg). 1073 They are enabled by setting \np{ln _icebergs}~=~true.1063 They are enabled by setting \np{ln\_icebergs}\forcode{ = .true.}. 1074 1064 1075 1065 Two initialisation schemes are possible. 1076 1066 \begin{description} 1077 \item[\np{nn _test_icebergs}~$>$~0]1078 In this scheme, the value of \np{nn _test_icebergs} represents the class of iceberg to generate1079 (so between 1 and 10), and \np{nn _test_icebergs} provides a lon/lat box in the domain at each1067 \item[\np{nn\_test\_icebergs}~$>$~0] 1068 In this scheme, the value of \np{nn\_test\_icebergs} represents the class of iceberg to generate 1069 (so between 1 and 10), and \np{nn\_test\_icebergs} provides a lon/lat box in the domain at each 1080 1070 grid point of which an iceberg is generated at the beginning of the run. 1081 (Note that this happens each time the timestep equals \np{nn _nit000}.)1082 \np{nn _test_icebergs} is defined by four numbers in \np{nn_test_box} representing the corners1071 (Note that this happens each time the timestep equals \np{nn\_nit000}.) 1072 \np{nn\_test\_icebergs} is defined by four numbers in \np{nn\_test\_box} representing the corners 1083 1073 of the geographical box: lonmin,lonmax,latmin,latmax 1084 \item[\np{nn _test_icebergs}~=~-1]1085 In this scheme the model reads a calving file supplied in the \np{sn _icb} parameter.1074 \item[\np{nn\_test\_icebergs}\forcode{ = -1}] 1075 In this scheme the model reads a calving file supplied in the \np{sn\_icb} parameter. 1086 1076 This should be a file with a field on the configuration grid (typically ORCA) representing ice accumulation rate at each model point. 1087 1077 These should be ocean points adjacent to land where icebergs are known to calve. … … 1095 1085 Icebergs are influenced by wind, waves and currents, bottom melt and erosion. 1096 1086 The latter act to disintegrate the iceberg. This is either all melted freshwater, or 1097 (if \np{rn _bits_erosion_fraction}~$>$~0) into melt and additionally small ice bits1087 (if \np{rn\_bits\_erosion\_fraction}~$>$~0) into melt and additionally small ice bits 1098 1088 which are assumed to propagate with their larger parent and thus delay fluxing into the ocean. 1099 1089 Melt water (and other variables on the configuration grid) are written into the main NEMO model output files. … … 1101 1091 Extensive diagnostics can be produced. 1102 1092 Separate output files are maintained for human-readable iceberg information. 1103 A separate file is produced for each processor (independent of \np{ln _ctl}).1093 A separate file is produced for each processor (independent of \np{ln\_ctl}). 1104 1094 The amount of information is controlled by two integer parameters: 1105 1095 \begin{description} 1106 \item[\np{nn _verbose_level}] takes a value between one and four and represents1096 \item[\np{nn\_verbose\_level}] takes a value between one and four and represents 1107 1097 an increasing number of points in the code at which variables are written, and an 1108 1098 increasing level of obscurity. 1109 \item[\np{nn _verbose_write}] is the number of timesteps between writes1099 \item[\np{nn\_verbose\_write}] is the number of timesteps between writes 1110 1100 \end{description} 1111 1101 1112 Iceberg trajectories can also be written out and this is enabled by setting \np{nn _sample_rate}~$>$~0.1102 Iceberg trajectories can also be written out and this is enabled by setting \np{nn\_sample\_rate}~$>$~0. 1113 1103 A non-zero value represents how many timesteps between writes of information into the output file. 1114 1104 These output files are in NETCDF format. … … 1128 1118 % Diurnal cycle 1129 1119 % ------------------------------------------------------------------------------------------------------------- 1130 \subsection [Diurnal cycle (\textit{sbcdcy})] 1131 {Diurnal cycle (\protect\mdl{sbcdcy})} 1120 \subsection{Diurnal cycle (\protect\mdl{sbcdcy})} 1132 1121 \label{SBC_dcy} 1133 1122 %------------------------------------------namsbc_rnf---------------------------------------------------- … … 1155 1144 the diurnal cycle of SWF is a scaling of the top of the atmosphere diurnal cycle 1156 1145 of incident SWF. The \cite{Bernie_al_CD07} reconstruction algorithm is available 1157 in \NEMO by setting \np{ln _dm2dc}~=~true(a \textit{\ngn{namsbc}} namelist variable) when using1158 CORE bulk formulea (\np{ln _blk_core}~=~true) or the flux formulation (\np{ln_flx}~=~true).1146 in \NEMO by setting \np{ln\_dm2dc}\forcode{ = .true.} (a \textit{\ngn{namsbc}} namelist variable) when using 1147 CORE bulk formulea (\np{ln\_blk\_core}\forcode{ = .true.}) or the flux formulation (\np{ln\_flx}\forcode{ = .true.}). 1159 1148 The reconstruction is performed in the \mdl{sbcdcy} module. The detail of the algoritm used 1160 1149 can be found in the appendix~A of \cite{Bernie_al_CD07}. The algorithm preserve the daily … … 1162 1151 of the analytical cycle over this time step (Fig.\ref{Fig_SBC_diurnal}). 1163 1152 The use of diurnal cycle reconstruction requires the input SWF to be daily 1164 ($i.e.$ a frequency of 24 and a time interpolation set to true in \np{sn _qsr} namelist parameter).1153 ($i.e.$ a frequency of 24 and a time interpolation set to true in \np{sn\_qsr} namelist parameter). 1165 1154 Furthermore, it is recommended to have a least 8 surface module time step per day, 1166 1155 that is $\rdt \ nn\_fsbc < 10,800~s = 3~h$. An example of recontructed SWF … … 1189 1178 \label{SBC_rotation} 1190 1179 1191 When using a flux (\ forcode{ln_flx = .true.}) or bulk (\forcode{ln_clio = .true.} or \forcode{ln_core= .true.}) formulation,1180 When using a flux (\np{ln\_flx}\forcode{ = .true.}) or bulk (\np{ln\_clio}\forcode{ = .true.} or \np{ln\_core}\forcode{ = .true.}) formulation, 1192 1181 pairs of vector components can be rotated from east-north directions onto the local grid directions. 1193 1182 This is particularly useful when interpolation on the fly is used since here any vectors are likely to be defined … … 1205 1194 % Surface restoring to observed SST and/or SSS 1206 1195 % ------------------------------------------------------------------------------------------------------------- 1207 \subsection [Surface restoring to observed SST and/or SSS (\textit{sbcssr})] 1208 {Surface restoring to observed SST and/or SSS (\protect\mdl{sbcssr})} 1196 \subsection{Surface restoring to observed SST and/or SSS (\protect\mdl{sbcssr})} 1209 1197 \label{SBC_ssr} 1210 1198 %------------------------------------------namsbc_ssr---------------------------------------------------- … … 1213 1201 1214 1202 IOptions are defined through the \ngn{namsbc\_ssr} namelist variables. 1215 n forced mode using a flux formulation (\np{ln _flx}~=~true), a1203 n forced mode using a flux formulation (\np{ln\_flx}\forcode{ = .true.}), a 1216 1204 feedback term \emph{must} be added to the surface heat flux $Q_{ns}^o$: 1217 1205 \begin{equation} \label{Eq_sbc_dmp_q} … … 1251 1239 The presence at the sea surface of an ice covered area modifies all the fluxes 1252 1240 transmitted to the ocean. There are several way to handle sea-ice in the system 1253 depending on the value of the \np{nn _ice} namelist parameter found in \ngn{namsbc} namelist.1241 depending on the value of the \np{nn\_ice} namelist parameter found in \ngn{namsbc} namelist. 1254 1242 \begin{description} 1255 1243 \item[nn{\_}ice = 0] there will never be sea-ice in the computational domain. … … 1275 1263 % {Description of Ice-ocean interface to be added here or in LIM 2 and 3 doc ?} 1276 1264 1277 \subsection [Interface to CICE (\textit{sbcice\_cice})] 1278 {Interface to CICE (\protect\mdl{sbcice\_cice})} 1265 \subsection{Interface to CICE (\protect\mdl{sbcice\_cice})} 1279 1266 \label{SBC_cice} 1280 1267 … … 1287 1274 \textit{calc\_strair~=~true} and \textit{calc\_Tsfc~=~true} in the CICE name-list), or alternatively when NEMO 1288 1275 is coupled to the HadGAM3 atmosphere model (with \textit{calc\_strair~=~false} and \textit{calc\_Tsfc~=~false}). 1289 The code is intended to be used with \np{nn _fsbc} set to 1 (although coupling ocean and ice less frequently1276 The code is intended to be used with \np{nn\_fsbc} set to 1 (although coupling ocean and ice less frequently 1290 1277 should work, it is possible the calculation of some of the ocean-ice fluxes needs to be modified slightly - the 1291 1278 user should check that results are not significantly different to the standard case). … … 1303 1290 % Freshwater budget control 1304 1291 % ------------------------------------------------------------------------------------------------------------- 1305 \subsection [Freshwater budget control (\textit{sbcfwb})] 1306 {Freshwater budget control (\protect\mdl{sbcfwb})} 1292 \subsection{Freshwater budget control (\protect\mdl{sbcfwb})} 1307 1293 \label{SBC_fwb} 1308 1294 … … 1311 1297 in the freshwater fluxes. In \NEMO, two way of controlling the the freshwater budget. 1312 1298 \begin{description} 1313 \item[\ forcode{nn_fwb= 0}] no control at all. The mean sea level is free to drift, and will1299 \item[\np{nn\_fwb}\forcode{ = 0}] no control at all. The mean sea level is free to drift, and will 1314 1300 certainly do so. 1315 \item[\ forcode{nn_fwb= 1}] global mean \textit{emp} set to zero at each model time step.1301 \item[\np{nn\_fwb}\forcode{ = 1}] global mean \textit{emp} set to zero at each model time step. 1316 1302 %Note that with a sea-ice model, this technique only control the mean sea level with linear free surface (\key{vvl} not defined) and no mass flux between ocean and ice (as it is implemented in the current ice-ocean coupling). 1317 \item[\ forcode{nn_fwb= 2}] freshwater budget is adjusted from the previous year annual1303 \item[\np{nn\_fwb}\forcode{ = 2}] freshwater budget is adjusted from the previous year annual 1318 1304 mean budget which is read in the \textit{EMPave\_old.dat} file. As the model uses the 1319 1305 Boussinesq approximation, the annual mean fresh water budget is simply evaluated … … 1325 1311 % Neutral Drag Coefficient from external wave model 1326 1312 % ------------------------------------------------------------------------------------------------------------- 1327 \subsection [Neutral drag coefficient from external wave model (\textit{sbcwave})]1328 1313 \subsection[Neutral drag coeff. from external wave model (\protect\mdl{sbcwave})] 1314 {Neutral drag coefficient from external wave model (\protect\mdl{sbcwave})} 1329 1315 \label{SBC_wave} 1330 1316 %------------------------------------------namwave---------------------------------------------------- … … 1332 1318 %------------------------------------------------------------------------------------------------------------- 1333 1319 1334 In order to read a neutral drag coeff , from an external data source ($i.e.$ a wave model), the1335 logical variable \np{ln _cdgw} in \ngn{namsbc} namelist must be set to \textit{true}.1336 The \mdl{sbcwave} module containing the routine \np{sbc _wave} reads the1320 In order to read a neutral drag coefficient, from an external data source ($i.e.$ a wave model), the 1321 logical variable \np{ln\_cdgw} in \ngn{namsbc} namelist must be set to \forcode{.true.}. 1322 The \mdl{sbcwave} module containing the routine \np{sbc\_wave} reads the 1337 1323 namelist \ngn{namsbc\_wave} (for external data names, locations, frequency, interpolation and all 1338 1324 the miscellanous options allowed by Input Data generic Interface see \S\ref{SBC_input})
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