Changeset 9392 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
r9389 r9392 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}~=~true), 31 a flux formulation (\np{ln_flx}~=~true), a bulk formulae formulation (CORE 32 (\np{ln_blk_core}~=~true), CLIO (\np{ln_blk_clio}~=~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}~=~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}~=~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. 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}~=~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). 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}=\textit{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 … … 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='./'. … … 214 214 \hline 215 215 & daily or weekLLL & monthly & yearly \\ \hline 216 clim = false & fn\_yYYYYmMMdDD & fn\_yYYYYmMM & fn\_yYYYY\\ \hline217 clim = true & not possible & fn\_m??.nc& fn \\ \hline216 clim = false & \ifile{fn\_yYYYYmMMdDD} & \ifile{fn\_yYYYYmMM} & \ifile{fn\_yYYYY} \\ \hline 217 clim = true & not possible & \ifile{fn\_m??} & 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}~=~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 … … 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}~=~\textit{true}) 441 441 \end{itemize} 442 442 … … 492 492 In this case, all the six fluxes needed by the ocean are assumed to 493 493 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.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. 496 496 In addition, the wind is allowed to reach its nominal value within a given number 497 of time steps (\np{nn \_tau000}).497 of time steps (\np{nn_tau000}). 498 498 499 499 If a user wants to apply a different analytical forcing, the \mdl{sbcana} … … 513 513 %------------------------------------------------------------------------------------------------------------- 514 514 515 In the flux formulation (\ np{ln\_flx}=true), the surface boundary515 In the flux formulation (\forcode{ln_flx = .true.}), the surface boundary 516 516 condition fields are directly read from input files. The user has to define 517 517 in the namelist \ngn{namsbc{\_}flx} the name of the file, the name of the variable … … 537 537 The atmospheric fields used depend on the bulk formulae used. Three bulk formulations 538 538 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}.539 one of the following namelist variable : \np{ln_core} ; \np{ln_clio} or \np{ln_mfs}. 540 540 541 541 Note : in forced mode, when a sea-ice model is used, a bulk formulation (CLIO or CORE) have to be used. … … 546 546 % CORE Bulk formulea 547 547 % ------------------------------------------------------------------------------------------------------------- 548 \subsection [CORE Bulk formulea (\protect\ np{ln\_core}=true)]549 {CORE Bulk formulea (\protect\ np{ln\_core}=true, \protect\mdl{sbcblk\_core})}548 \subsection [CORE Bulk formulea (\protect\forcode{ln_core = .true.})] 549 {CORE Bulk formulea (\protect\forcode{ln_core = .true.}, \protect\mdl{sbcblk\_core})} 550 550 \label{SBC_blk_core} 551 551 %------------------------------------------namsbc_core---------------------------------------------------- … … 592 592 or larger than the one of the input atmospheric fields. 593 593 594 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 fields594 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 fields 596 596 and the way they have to be used (spatial and temporal interpolations). 597 597 598 \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)598 \np{cn_dir} is the directory of location of bulk files 599 \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) 602 602 603 603 Three multiplicative factors are availables : 604 \np{rn \_pfac} and \np{rn\_efac} allows to adjust (if necessary) the global freshwater budget604 \np{rn_pfac} and \np{rn_efac} allows to adjust (if necessary) the global freshwater budget 605 605 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 account606 The third one,\np{rn_vfac}, control to which extend the ice/ocean velocities are taken into account 607 607 in the calculation of surface wind stress. Its range should be between zero and one, 608 608 and it is recommended to set it to 0. … … 611 611 % CLIO Bulk formulea 612 612 % ------------------------------------------------------------------------------------------------------------- 613 \subsection [CLIO Bulk formulea (\protect\ np{ln\_clio}=true)]614 {CLIO Bulk formulea (\protect\ np{ln\_clio}=true, \protect\mdl{sbcblk\_clio})}613 \subsection [CLIO Bulk formulea (\protect\forcode{ln_clio = .true.})] 614 {CLIO Bulk formulea (\protect\forcode{ln_clio = .true.}, \protect\mdl{sbcblk\_clio})} 615 615 \label{SBC_blk_clio} 616 616 %------------------------------------------namsbc_clio---------------------------------------------------- … … 652 652 % MFS Bulk formulae 653 653 % ------------------------------------------------------------------------------------------------------------- 654 \subsection [MFS Bulk formulea (\protect\ np{ln\_mfs}=true)]655 {MFS Bulk formulea (\protect\ np{ln\_mfs}=true, \protect\mdl{sbcblk\_mfs})}654 \subsection [MFS Bulk formulea (\protect\forcode{ln_mfs = .true.})] 655 {MFS Bulk formulea (\protect\forcode{ln_mfs = .true.}, \protect\mdl{sbcblk\_mfs})} 656 656 \label{SBC_blk_mfs} 657 657 %------------------------------------------namsbc_mfs---------------------------------------------------- … … 679 679 The required 7 input fields must be provided on the model Grid-T and are: 680 680 \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})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}) 688 688 \end{itemize} 689 689 % ------------------------------------------------------------------------------------------------------------- … … 709 709 as well as to \href{http://wrf-model.org/}{WRF} (Weather Research and Forecasting Model). 710 710 711 Note that in addition to the setting of \np{ln \_cpl} to true, the \key{coupled} have to be defined.711 Note that in addition to the setting of \np{ln_cpl} to true, the \key{coupled} have to be defined. 712 712 The CPP key is mainly used in sea-ice to ensure that the atmospheric fluxes are 713 713 actually recieved by the ice-ocean system (no calculation of ice sublimation in coupled mode). … … 738 738 739 739 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)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) 742 742 can be interpolated in time to the model time step, and even in space when the 743 743 interpolation on-the-fly is used. When used to force the dynamics, the atmospheric … … 748 748 \end{equation} 749 749 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$750 A value of $101,000~N/m^2$ is used unless \np{ln_ref_apr} is set to true. In this case $P_o$ 751 751 is set to the value of $P_{atm}$ averaged over the ocean domain, $i.e.$ the mean value of 752 752 $\eta_{ib}$ is kept to zero at all time step. … … 760 760 When using time-splitting and BDY package for open boundaries conditions, the equivalent 761 761 inverse barometer sea surface height $\eta_{ib}$ can be added to BDY ssh data: 762 \np{ln \_apr\_obc} might be set to true.762 \np{ln_apr_obc} might be set to true. 763 763 764 764 % ================================================================ … … 774 774 775 775 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}.776 This option is activated when \np{ln_tide} is set to true in \ngn{nam\_tide}. 777 777 778 778 Some parameters are available in namelist \ngn{nam\_tide}: 779 779 780 - \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 used780 - \np{ln_tide_load} activate the load potential forcing and \np{filetide_load} is the associated file 781 782 - \np{ln_tide_pot} activate the tidal potential forcing 783 784 - \np{nb_harmo} is the number of constituent used 785 785 786 786 - \np{clname} is the name of constituent … … 863 863 depth (in metres) which the river should be added to. 864 864 865 Namelist variables in \ngn{namsbc\_rnf}, \np{ln \_rnf\_depth}, \np{ln\_rnf\_sal} and \np{ln\_rnf\_temp} control whether865 Namelist variables in \ngn{namsbc\_rnf}, \np{ln_rnf_depth}, \np{ln_rnf_sal} and \np{ln_rnf_temp} control whether 866 866 the river attributes (depth, salinity and temperature) are read in and used. If these are set 867 867 as false the river is added to the surface box only, assumed to be fresh (0~psu), and/or … … 876 876 to give the heat and salt content of the river runoff. 877 877 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}.878 calculated and stored in the variable \np{nz_rnf}. 879 879 The variable \textit{h\_dep} is then calculated to be the depth (in metres) of the bottom of the 880 880 lowest box the river water is being added to (i.e. the total depth that river water is being added to in the model). … … 943 943 \forfile{../namelists/namsbc_isf} 944 944 %-------------------------------------------------------------------------------------------------------- 945 Namelist variable in \ngn{namsbc}, \np{nn \_isf}, controls the ice shelf representation used.945 Namelist variable in \ngn{namsbc}, \np{nn_isf}, controls the ice shelf representation used. 946 946 \begin{description} 947 \item[\np{nn \_isf}~=~1]948 The ice shelf cavity is represented (\np{ln \_isfcav}~=~true needed). The fwf and heat flux are computed.947 \item[\np{nn_isf}~=~1] 948 The ice shelf cavity is represented (\np{ln_isfcav}~=~true needed). The fwf and heat flux are computed. 949 949 Two different bulk formula are available: 950 950 \begin{description} 951 \item[\np{nn \_isfblk}~=~1]951 \item[\np{nn_isfblk}~=~1] 952 952 The bulk formula used to compute the melt is based the one described in \citet{Hunter2006}. 953 953 This formulation is based on a balance between the upward ocean heat flux and the latent heat flux at the ice shelf base. 954 954 955 \item[\np{nn \_isfblk}~=~2]955 \item[\np{nn_isfblk}~=~2] 956 956 The bulk formula used to compute the melt is based the one described in \citet{Jenkins1991}. 957 957 This formulation is based on a 3 equations formulation (a heat flux budget, a salt flux budget … … 962 962 \begin{description} 963 963 \item[\np{nn\_gammablk~=~0~}] 964 The salt and heat exchange coefficients are constant and defined by \np{rn \_gammas0} and \np{rn\_gammat0}964 The salt and heat exchange coefficients are constant and defined by \np{rn_gammas0} and \np{rn_gammat0} 965 965 966 966 \item[\np{nn\_gammablk~=~1~}] 967 967 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).968 where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_hisf_tbl} meters). 969 969 See \citet{Jenkins2010} for all the details on this formulation. 970 970 … … 972 972 The salt and heat exchange coefficients are velocity and stability dependent and defined as 973 973 $\gamma_{T,S} = \frac{u_{*}}{\Gamma_{Turb} + \Gamma^{T,S}_{Mole}}$ 974 where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn \_hisf\_tbl} meters),974 where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_hisf_tbl} meters), 975 975 $\Gamma_{Turb}$ the contribution of the ocean stability and 976 976 $\Gamma^{T,S}_{Mole}$ the contribution of the molecular diffusion. … … 978 978 \end{description} 979 979 980 \item[\np{nn \_isf}~=~2]980 \item[\np{nn_isf}~=~2] 981 981 A parameterisation of isf is used. The ice shelf cavity is not represented. 982 982 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).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). 984 984 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]985 The effective melting length (\np{sn_Leff_isf}) is read from a file. 986 987 \item[\np{nn_isf}~=~3] 988 988 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}).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}). 991 991 The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 992 992 993 \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}).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}). 995 995 The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$.\\ 996 996 \end{description} 997 997 998 998 999 $\bullet$ \np{nn \_isf}~=~1 and \np{nn\_isf}~=~2 compute a melt rate based on the water mass properties, ocean velocities and depth.999 $\bullet$ \np{nn_isf}~=~1 and \np{nn_isf}~=~2 compute a melt rate based on the water mass properties, ocean velocities and depth. 1000 1000 This flux is thus highly dependent of the model resolution (horizontal and vertical), realism of the water masses onto the shelf ...\\ 1001 1001 1002 1002 1003 $\bullet$ \np{nn \_isf}~=~3 and \np{nn\_isf}~=~4 read the melt rate from a file. You have total control of the fwf forcing.1003 $\bullet$ \np{nn_isf}~=~3 and \np{nn_isf}~=~4 read the melt rate from a file. You have total control of the fwf forcing. 1004 1004 This can be usefull if the water masses on the shelf are not realistic or the resolution (horizontal/vertical) are too 1005 1005 coarse to have realistic melting or for studies where you need to control your heat and fw input.\\ 1006 1006 1007 1007 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).\\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}~=~4 1010 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).\\ 1014 1014 1015 1015 The ice shelf melt is implemented as a volume flux with in the same way as for the runoff. … … 1043 1043 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 1044 \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,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, 1046 1046 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 1047 This coupling procedure is able to take into account grounding line and calving front migration. However, it is a non-conservative processe. … … 1049 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. 1050 1050 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.\\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.\\ 1053 1053 1054 1054 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 1068 Icebergs are initially spawned into one of ten classes which have specific mass and thickness as described 1069 1069 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 icebergs1070 \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 icebergs 1072 1072 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.1073 They are enabled by setting \np{ln_icebergs}~=~true. 1074 1074 1075 1075 Two initialisation schemes are possible. 1076 1076 \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 each1077 \item[\np{nn_test_icebergs}~$>$~0] 1078 In this scheme, the value of \np{nn_test_icebergs} represents the class of iceberg to generate 1079 (so between 1 and 10), and \np{nn_test_icebergs} provides a lon/lat box in the domain at each 1080 1080 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 corners1081 (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 corners 1083 1083 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.1084 \item[\np{nn_test_icebergs}~=~-1] 1085 In this scheme the model reads a calving file supplied in the \np{sn_icb} parameter. 1086 1086 This should be a file with a field on the configuration grid (typically ORCA) representing ice accumulation rate at each model point. 1087 1087 These should be ocean points adjacent to land where icebergs are known to calve. … … 1095 1095 Icebergs are influenced by wind, waves and currents, bottom melt and erosion. 1096 1096 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 bits1097 (if \np{rn_bits_erosion_fraction}~$>$~0) into melt and additionally small ice bits 1098 1098 which are assumed to propagate with their larger parent and thus delay fluxing into the ocean. 1099 1099 Melt water (and other variables on the configuration grid) are written into the main NEMO model output files. … … 1101 1101 Extensive diagnostics can be produced. 1102 1102 Separate output files are maintained for human-readable iceberg information. 1103 A separate file is produced for each processor (independent of \np{ln \_ctl}).1103 A separate file is produced for each processor (independent of \np{ln_ctl}). 1104 1104 The amount of information is controlled by two integer parameters: 1105 1105 \begin{description} 1106 \item[\np{nn \_verbose\_level}] takes a value between one and four and represents1106 \item[\np{nn_verbose_level}] takes a value between one and four and represents 1107 1107 an increasing number of points in the code at which variables are written, and an 1108 1108 increasing level of obscurity. 1109 \item[\np{nn \_verbose\_write}] is the number of timesteps between writes1109 \item[\np{nn_verbose_write}] is the number of timesteps between writes 1110 1110 \end{description} 1111 1111 1112 Iceberg trajectories can also be written out and this is enabled by setting \np{nn \_sample\_rate}~$>$~0.1112 Iceberg trajectories can also be written out and this is enabled by setting \np{nn_sample_rate}~$>$~0. 1113 1113 A non-zero value represents how many timesteps between writes of information into the output file. 1114 1114 These output files are in NETCDF format. … … 1155 1155 the diurnal cycle of SWF is a scaling of the top of the atmosphere diurnal cycle 1156 1156 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).1157 in \NEMO by setting \np{ln_dm2dc}~=~true (a \textit{\ngn{namsbc}} namelist variable) when using 1158 CORE bulk formulea (\np{ln_blk_core}~=~true) or the flux formulation (\np{ln_flx}~=~true). 1159 1159 The reconstruction is performed in the \mdl{sbcdcy} module. The detail of the algoritm used 1160 1160 can be found in the appendix~A of \cite{Bernie_al_CD07}. The algorithm preserve the daily … … 1162 1162 of the analytical cycle over this time step (Fig.\ref{Fig_SBC_diurnal}). 1163 1163 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).1164 ($i.e.$ a frequency of 24 and a time interpolation set to true in \np{sn_qsr} namelist parameter). 1165 1165 Furthermore, it is recommended to have a least 8 surface module time step per day, 1166 1166 that is $\rdt \ nn\_fsbc < 10,800~s = 3~h$. An example of recontructed SWF … … 1189 1189 \label{SBC_rotation} 1190 1190 1191 When using a flux (\ np{ln\_flx}=true) or bulk (\np{ln\_clio}=true or \np{ln\_core}=true) formulation,1191 When using a flux (\forcode{ln_flx = .true.}) or bulk (\forcode{ln_clio = .true.} or \forcode{ln_core = .true.}) formulation, 1192 1192 pairs of vector components can be rotated from east-north directions onto the local grid directions. 1193 1193 This is particularly useful when interpolation on the fly is used since here any vectors are likely to be defined … … 1213 1213 1214 1214 IOptions are defined through the \ngn{namsbc\_ssr} namelist variables. 1215 n forced mode using a flux formulation (\np{ln \_flx}~=~true), a1215 n forced mode using a flux formulation (\np{ln_flx}~=~true), a 1216 1216 feedback term \emph{must} be added to the surface heat flux $Q_{ns}^o$: 1217 1217 \begin{equation} \label{Eq_sbc_dmp_q} … … 1251 1251 The presence at the sea surface of an ice covered area modifies all the fluxes 1252 1252 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.1253 depending on the value of the \np{nn_ice} namelist parameter found in \ngn{namsbc} namelist. 1254 1254 \begin{description} 1255 1255 \item[nn{\_}ice = 0] there will never be sea-ice in the computational domain. … … 1287 1287 \textit{calc\_strair~=~true} and \textit{calc\_Tsfc~=~true} in the CICE name-list), or alternatively when NEMO 1288 1288 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 frequently1289 The code is intended to be used with \np{nn_fsbc} set to 1 (although coupling ocean and ice less frequently 1290 1290 should work, it is possible the calculation of some of the ocean-ice fluxes needs to be modified slightly - the 1291 1291 user should check that results are not significantly different to the standard case). … … 1311 1311 in the freshwater fluxes. In \NEMO, two way of controlling the the freshwater budget. 1312 1312 \begin{description} 1313 \item[\ np{nn\_fwb}=0] no control at all. The mean sea level is free to drift, and will1313 \item[\forcode{nn_fwb = 0}] no control at all. The mean sea level is free to drift, and will 1314 1314 certainly do so. 1315 \item[\ np{nn\_fwb}=1] global mean \textit{emp} set to zero at each model time step.1315 \item[\forcode{nn_fwb = 1}] global mean \textit{emp} set to zero at each model time step. 1316 1316 %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[\ np{nn\_fwb}=2] freshwater budget is adjusted from the previous year annual1317 \item[\forcode{nn_fwb = 2}] freshwater budget is adjusted from the previous year annual 1318 1318 mean budget which is read in the \textit{EMPave\_old.dat} file. As the model uses the 1319 1319 Boussinesq approximation, the annual mean fresh water budget is simply evaluated … … 1333 1333 1334 1334 In order to read a neutral drag coeff, from an external data source ($i.e.$ a wave model), the 1335 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 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 the 1337 1337 namelist \ngn{namsbc\_wave} (for external data names, locations, frequency, interpolation and all 1338 1338 the miscellanous options allowed by Input Data generic Interface see \S\ref{SBC_input})
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