Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/NEMO_manual_state.txt
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/NEMO_manual_state.txt	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/NEMO_manual_state.txt	(revision 13998)
@@ -39,5 +39,5 @@
          namdia: iiceprt jiceprt
     nam_diaharm: nit000_han nitend_han nstep_han tname(1) tname(2)
-         namdrg: ln_OFF
+         namdrg: ln_drg_OFF
      namdrg_bot: rn_Cd0 rn_Uc0 rn_Cdmax
      namdrg_top: rn_Cd0 rn_Uc0 rn_Cdmax
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/latex/NEMO/subfiles/chap_TRA.tex
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/latex/NEMO/subfiles/chap_TRA.tex	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/latex/NEMO/subfiles/chap_TRA.tex	(revision 13998)
@@ -1229,5 +1229,5 @@
 In the computer code, a density anomaly, $d_a = \rho / \rho_o - 1$, is computed,
 with $\rho_o$ a reference density.
-Called \textit{rau0} in the code,
+Called \textit{rho0} in the code,
 $\rho_o$ is set in \mdl{phycst} to a value of \texttt{1,026} $Kg/m^3$.
 This is a sensible choice for the reference density used in a Boussinesq ocean climate model,
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/latex/NEMO/subfiles/chap_ZDF.tex
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/latex/NEMO/subfiles/chap_ZDF.tex	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/latex/NEMO/subfiles/chap_ZDF.tex	(revision 13998)
@@ -1160,5 +1160,5 @@
 \]
 When \np[=.true.]{ln_lin}{ln\_lin}, the value of $r$ used is \np{rn_Uc0}{rn\_Uc0}*\np{rn_Cd0}{rn\_Cd0}.
-Setting \np[=.true.]{ln_OFF}{ln\_OFF} (and \forcode{ln_lin=.true.}) is equivalent to setting $r=0$ and leads to a free-slip boundary condition.
+Setting \np[=.true.]{ln_drg_OFF}{ln\_OFF} (and \forcode{ln_lin=.true.}) is equivalent to setting $r=0$ and leads to a free-slip boundary condition.
 
 These values are assigned in \mdl{zdfdrg}.
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/nambdy_dta
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/nambdy_dta	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/nambdy_dta	(revision 13998)
@@ -29,4 +29,5 @@
    bn_aip      = 'NOT USED'              ,         24.       , 'siapnd'  ,    .true.   , .false.,  'daily'  ,    ''            ,   ''     ,     ''
    bn_hip      = 'NOT USED'              ,         24.       , 'sihpnd'  ,    .true.   , .false.,  'daily'  ,    ''            ,   ''     ,     ''
+   bn_hil      = 'NOT USED'              ,         24.       , 'sihlid'  ,    .true.   , .false.,  'daily'  ,    ''            ,   ''     ,     ''
    ! if bn_t_i etc are "not used", then define arbitrary temperatures and salinity and ponds
    rn_ice_tem  = 270.         !  arbitrary temperature               of incoming sea ice
@@ -35,3 +36,4 @@
    rn_ice_apnd = 0.2          !       --   pond fraction = a_ip/a_i            --
    rn_ice_hpnd = 0.05         !       --   pond depth                          --
+   rn_ice_hlid = 0.0          !       --   pond lid depth                      --
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdia
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdia	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdia	(revision 13998)
@@ -8,5 +8,5 @@
    ln_icediahsb     = .false.         !  output the heat, mass & salt budgets (T) or not (F)
    ln_icectl        = .false.         !  ice points output for debug (T or F)
-   iiceprt          =  10             !  i-index for debug
-   jiceprt          =  10             !  j-index for debug
+      iiceprt       =  10             !     i-index for debug
+      jiceprt       =  10             !     j-index for debug
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg	(revision 13998)
@@ -2,5 +2,5 @@
 &namdrg        !   top/bottom drag coefficient                          (default: NO selection)
 !-----------------------------------------------------------------------
-   ln_OFF      = .false.   !  free-slip       : Cd = 0                  (F => fill namdrg_bot
+   ln_drg_OFF  = .false.   !  free-slip       : Cd = 0                  (F => fill namdrg_bot
    ln_lin      = .false.   !      linear  drag: Cd = Cd0 Uc0                   &   namdrg_top)
    ln_non_lin  = .false.   !  non-linear  drag: Cd = Cd0 |U|
@@ -8,3 +8,4 @@
    !
    ln_drgimp   = .true.    !  implicit top/bottom friction flag
+      ln_drgice_imp = .false. ! implicit ice-ocean drag
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg_bot
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg_bot	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg_bot	(revision 13998)
@@ -1,4 +1,4 @@
 !-----------------------------------------------------------------------
-&namdrg_bot    !   BOTTOM friction                                      (ln_OFF =F)
+&namdrg_bot    !   BOTTOM friction                                      (ln_drg_OFF =F)
 !-----------------------------------------------------------------------
    rn_Cd0      =  1.e-3    !  drag coefficient [-]
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg_top
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg_top	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdrg_top	(revision 13998)
@@ -1,4 +1,4 @@
 !-----------------------------------------------------------------------
-&namdrg_top    !   TOP friction                                         (ln_OFF =F & ln_isfcav=T)
+&namdrg_top    !   TOP friction                                         (ln_drg_OFF =F & ln_isfcav=T)
 !-----------------------------------------------------------------------
    rn_Cd0      =  1.e-3    !  drag coefficient [-]
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdyn
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdyn	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdyn	(revision 13998)
@@ -10,8 +10,8 @@
    rn_ishlat        =   2.            !  lbc : free slip (0) ; partial slip (0-2) ; no slip (2) ; strong slip (>2)
    ln_landfast_L16  = .false.         !  landfast: parameterization from Lemieux 2016
-      rn_depfra     =   0.125         !        fraction of ocean depth that ice must reach to initiate landfast
+      rn_lf_depfra  =   0.125         !        fraction of ocean depth that ice must reach to initiate landfast
                                       !          recommended range: [0.1 ; 0.25]
-      rn_icebfr     =  15.            !        maximum bottom stress per unit volume [N/m3]
-      rn_lfrelax    =   1.e-5         !        relaxation time scale to reach static friction [s-1]
-      rn_tensile    =   0.05          !        isotropic tensile strength [0-0.5??]
+      rn_lf_bfr     =  15.            !        maximum bottom stress per unit volume [N/m3]
+      rn_lf_relax   =   1.e-5         !        relaxation time scale to reach static friction [s-1]
+      rn_lf_tensile =   0.05          !        isotropic tensile strength [0-0.5??]
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdyn_rhg
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdyn_rhg	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namdyn_rhg	(revision 13998)
@@ -9,3 +9,4 @@
       rn_relast     =   0.333         !     ratio of elastic timescale to ice time step: Telast = dt_ice * rn_relast 
                                       !        advised value: 1/3 (rn_nevp=120) or 1/9 (rn_nevp=300)
+   ln_rhg_chkcvg    = .false.         !  check convergence of rheology (outputs: file ice_cvg.nc & variable uice_cvg)
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/nameos
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/nameos	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/nameos	(revision 13998)
@@ -7,5 +7,5 @@
                                  !
    !                     ! S-EOS coefficients (ln_seos=T):
-   !                             !  rd(T,S,Z)*rau0 = -a0*(1+.5*lambda*dT+mu*Z+nu*dS)*dT+b0*dS
+   !                             !  rd(T,S,Z)*rho0 = -a0*(1+.5*lambda*dT+mu*Z+nu*dS)*dT+b0*dS
    rn_a0       =  1.6550e-1      !  thermal expension coefficient
    rn_b0       =  7.6554e-1      !  saline  expension coefficient
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namini
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namini	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namini	(revision 13998)
@@ -3,5 +3,7 @@
 !------------------------------------------------------------------------------
    ln_iceini        = .true.          !  activate ice initialization (T) or not (F)
-   ln_iceini_file   = .false.         !  netcdf file provided for initialization (T) or not (F)
+   nn_iceini_file   =   0             !     0 = Initialise sea ice based on SSTs
+                                      !     1 = Initialise sea ice from single category netcdf file
+                                      !     2 = Initialise sea ice from multi category restart file
    rn_thres_sst     =   2.0           !  max temp. above Tfreeze with initial ice = (sst - tfreeze)
    rn_hti_ini_n     =   3.0           !  initial ice thickness       (m), North
@@ -23,5 +25,7 @@
    rn_hpd_ini_n     =   0.05          !  initial pond depth          (m), North
    rn_hpd_ini_s     =   0.05          !        "            "             South
-   ! -- for ln_iceini_file = T
+   rn_hld_ini_n     =   0.0           !  initial pond lid depth      (m), North
+   rn_hld_ini_s     =   0.0           !        "            "             South
+   ! -- for nn_iceini_file = 1
    sn_hti = 'Ice_initialization'    , -12 ,'hti'   ,  .false.  , .true., 'yearly'  , '' , '', ''
    sn_hts = 'Ice_initialization'    , -12 ,'hts'   ,  .false.  , .true., 'yearly'  , '' , '', ''
@@ -34,4 +38,5 @@
    sn_apd = 'NOT USED'              , -12 ,'apd'   ,  .false.  , .true., 'yearly'  , '' , '', ''
    sn_hpd = 'NOT USED'              , -12 ,'hpd'   ,  .false.  , .true., 'yearly'  , '' , '', ''
+   sn_hld = 'NOT USED'              , -12 ,'hld'   ,  .false.  , .true., 'yearly'  , '' , '', ''
    cn_dir='./'
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namsbc_blk
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namsbc_blk	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namsbc_blk	(revision 13998)
@@ -35,8 +35,11 @@
    sn_tair     = 't_10.15JUNE2009_fill'       ,    6.        , 'T_10_MOD',   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , ''       , ''
    sn_humi     = 'q_10.15JUNE2009_fill'       ,    6.        , 'Q_10_MOD',   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , ''       , ''
-   sn_hpgi     = 'NONE'                       ,   24.        , 'uhpg'    ,   .false.   , .false., 'monthly' , 'weights_ERAI3D_F128_2_ORCA2_bicubic', 'UG'     , ''
-   sn_hpgj     = 'NONE'                       ,   24.        , 'vhpg'    ,   .false.   , .false., 'monthly' , 'weights_ERAI3D_F128_2_ORCA2_bicubic', 'VG'     , ''
    sn_prec     = 'ncar_precip.15JUNE2009_fill',   -1.        , 'PRC_MOD1',   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , ''       , ''
    sn_snow     = 'ncar_precip.15JUNE2009_fill',   -1.        , 'SNOW'    ,   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , ''       , ''
    sn_slp      = 'slp.15JUNE2009_fill'        ,    6.        , 'SLP'     ,   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , ''       , ''
+   sn_uoatm    = 'NOT USED'                   ,    6.        , 'UOATM'   ,   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , 'Uoceatm', ''
+   sn_voatm    = 'NOT USED'                   ,    6.        , 'VOATM'   ,   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , 'Voceatm', ''
+   sn_cc       = 'NOT USED'                   ,   24.        , 'CC'      ,   .false.   , .true. , 'yearly'  , 'weights_core_orca2_bilinear_noc.nc' , ''       , ''
+   sn_hpgi     = 'NOT USED'                   ,   24.        , 'uhpg'    ,   .false.   , .false., 'monthly' , 'weights_ERAI3D_F128_2_ORCA2_bicubic', 'UG'     , ''
+   sn_hpgj     = 'NOT USED'                   ,   24.        , 'vhpg'    ,   .false.   , .false., 'monthly' , 'weights_ERAI3D_F128_2_ORCA2_bicubic', 'VG'     , ''
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namsbc_cpl
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namsbc_cpl	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namsbc_cpl	(revision 13998)
@@ -2,9 +2,9 @@
 &namsbc_cpl    !   coupled ocean/atmosphere model                       ("key_oasis3")
 !-----------------------------------------------------------------------
-   nn_cplmodel   =     1   !  Maximum number of models to/from which NEMO is potentially sending/receiving data
-   ln_usecplmask = .false. !  use a coupling mask file to merge data received from several models
-   !                       !   -> file cplmask.nc with the float variable called cplmask (jpi,jpj,nn_cplmodel)
-   nn_cats_cpl   =     5   !  Number of sea ice categories over which coupling is to be carried out (if not 1)
-
+   nn_cplmodel       =     1   !  Maximum number of models to/from which NEMO is potentially sending/receiving data
+   ln_usecplmask     = .false. !  use a coupling mask file to merge data received from several models
+   !                           !   -> file cplmask.nc with the float variable called cplmask (jpi,jpj,nn_cplmodel)
+   ln_scale_ice_flux = .false. !  use ice fluxes that are already "ice weighted" ( i.e. multiplied ice concentration)
+   nn_cats_cpl       =     5   !  Number of sea ice categories over which coupling is to be carried out (if not 1)
    !_____________!__________________________!____________!_____________!______________________!________!
    !             !        description       !  multiple  !    vector   !       vector         ! vector !
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd	(revision 13998)
@@ -6,3 +6,5 @@
    ln_icedO         = .true.          !  activate ice growth in open-water (T) or not (F)
    ln_icedS         = .true.          !  activate brine drainage (T) or not (F)
+   !                                   
+   ln_leadhfx       = .true.          !  heat in the leads is used to melt sea-ice before warming the ocean
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd_pnd
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd_pnd	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd_pnd	(revision 13998)
@@ -2,9 +2,12 @@
 &namthd_pnd     !   Melt ponds
 !------------------------------------------------------------------------------
-   ln_pnd           = .false.         !  activate melt ponds or not
-     ln_pnd_H12     = .false.         !  activate evolutive melt ponds (from Holland et al 2012)
-     ln_pnd_CST     = .false.         !  activate constant  melt ponds
-       rn_apnd      =   0.2           !     prescribed pond fraction, at Tsu=0 degC
-       rn_hpnd      =   0.05          !     prescribed pond depth,    at Tsu=0 degC
-     ln_pnd_alb     = .false.         !  melt ponds affect albedo or not
+   ln_pnd            = .false.        !  activate melt ponds or not
+      ln_pnd_LEV     = .false.        !  level ice melt ponds (from Flocco et al 2007,2010 & Holland et al 2012)
+         rn_apnd_min =   0.15         !     minimum ice fraction that contributes to melt pond. range: 0.0 -- 0.15 ??
+         rn_apnd_max =   0.85         !     maximum ice fraction that contributes to melt pond. range: 0.7 -- 0.85 ??
+      ln_pnd_CST     = .false.        !  constant  melt ponds
+         rn_apnd     =   0.2          !     prescribed pond fraction, at Tsu=0 degC
+         rn_hpnd     =   0.05         !     prescribed pond depth,    at Tsu=0 degC
+      ln_pnd_lids    = .true.         !  frozen lids on top of the ponds (only for ln_pnd_LEV)
+      ln_pnd_alb     = .true.         !  effect of melt ponds on ice albedo
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd_zdf
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd_zdf	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namthd_zdf	(revision 13998)
@@ -7,4 +7,8 @@
    rn_cnd_s         =   0.31          !  thermal conductivity of the snow (0.31 W/m/K, Maykut and Untersteiner, 1971)
                                       !     Obs: 0.1-0.5 (Lecomte et al, JAMES 2013)
-   rn_kappa_i       =   1.0           !  radiation attenuation coefficient in sea ice [1/m]
+   rn_kappa_i       =   1.0           !  radiation attenuation coefficient in sea ice                     [1/m]
+   rn_kappa_s       =  10.0           !  nn_qtrice = 0: radiation attenuation coefficient in snow         [1/m]
+   rn_kappa_smlt    =   7.0           !  nn_qtrice = 1: radiation attenuation coefficient in melting snow [1/m]
+   rn_kappa_sdry    =  10.0           !                 radiation attenuation coefficient in dry snow     [1/m]
+   ln_zdf_chkcvg    = .false.         !  check convergence of heat diffusion scheme (output variable: tice_cvg)
 /
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namzdf_gls
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namzdf_gls	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namzdf_gls	(revision 13998)
@@ -13,4 +13,9 @@
    nn_z0_met     =     2   !  Method for surface roughness computation (0/1/2/3)
    !                             ! =3 requires ln_wave=T
+   nn_z0_ice     =   1     !  attenutaion of surface wave breaking under ice
+   !                       !           = 0 no impact of ice cover
+   !                       !           = 1 roughness uses rn_hsri and is weigthed by 1-TANH(10*fr_i)
+   !                       !           = 2 roughness uses rn_hsri and is weighted by 1-fr_i
+   !                       !           = 3 roughness uses rn_hsri and is weighted by 1-MIN(1,4*fr_i)
    nn_bc_surf    =     1   !  surface condition (0/1=Dir/Neum)
    nn_bc_bot     =     1   !  bottom condition (0/1=Dir/Neum)
Index: NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namzdf_tke
===================================================================
--- NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namzdf_tke	(revision 13426)
+++ NEMO/branches/2020/dev_r13327_KERNEL-06_2_techene_e3/doc/namelists/namzdf_tke	(revision 13998)
@@ -15,5 +15,4 @@
    ln_mxl0     = .true.    !  surface mixing length scale = F(wind stress) (T) or not (F)
    rn_mxl0     =   0.04    !  surface  buoyancy lenght scale minimum value
-   ln_drg      = .false.   !  top/bottom friction added as boundary condition of TKE
    ln_lc       = .true.    !  Langmuir cell parameterisation (Axell 2002)
       rn_lc       =   0.15    !  coef. associated to Langmuir cells
@@ -26,4 +25,8 @@
                               !        = 0  constant 10 m length scale
                               !        = 1  0.5m at the equator to 30m poleward of 40 degrees
-      rn_eice     =   4       !  below sea ice: =0 ON ; =4 OFF when ice fraction > 1/4   
+   nn_eice     =   1       !  attenutaion of langmuir & surface wave breaking under ice
+   !                       !           = 0 no impact of ice cover on langmuir & surface wave breaking
+   !                       !           = 1 weigthed by 1-TANH(10*fr_i)
+   !                       !           = 2 weighted by 1-fr_i
+   !                       !           = 3 weighted by 1-MIN(1,4*fr_i)
 /
