[13655] | 1 | MODULE sbcblk_algo_ice_lu12 |
---|
| 2 | !!====================================================================== |
---|
| 3 | !! *** MODULE sbcblk_algo_ice_lu12 *** |
---|
| 4 | !! Computes turbulent components of surface fluxes over sea-ice |
---|
| 5 | !! |
---|
| 6 | !! Lüpkes, C., Gryanik, V. M., Hartmann, J., and Andreas, E. L. ( 2012), A parametrization, based on sea ice morphology, |
---|
| 7 | !! of the neutral atmospheric drag coefficients for weather prediction and climate models, J. Geophys. Res., 117, D13112, |
---|
| 8 | !! doi:10.1029/2012JD017630. |
---|
| 9 | !! |
---|
| 10 | !! => Despite the fact that the sea-ice concentration (frice) must be provided, |
---|
| 11 | !! only transfer coefficients, and air temp. + hum. height adjustement |
---|
| 12 | !! over ice are returned/performed. |
---|
| 13 | !! ==> 'frice' is only here to estimate the form drag caused by sea-ice... |
---|
| 14 | !! |
---|
| 15 | !! Routine turb_ice_lu12 maintained and developed in AeroBulk |
---|
| 16 | !! (https://github.com/brodeau/aerobulk/) |
---|
| 17 | !! |
---|
| 18 | !! Author: Laurent Brodeau, Summer 2020 |
---|
| 19 | !! |
---|
| 20 | !!---------------------------------------------------------------------- |
---|
| 21 | USE par_kind, ONLY: wp |
---|
| 22 | USE par_oce, ONLY: jpi, jpj |
---|
| 23 | USE phycst ! physical constants |
---|
[13719] | 24 | USE sbc_phy ! Catalog of functions for physical/meteorological parameters in the marine boundary layer |
---|
[13655] | 25 | USE sbcblk_algo_ice_cdn |
---|
| 26 | |
---|
| 27 | IMPLICIT NONE |
---|
| 28 | PRIVATE |
---|
| 29 | |
---|
| 30 | PUBLIC :: turb_ice_lu12 |
---|
| 31 | |
---|
| 32 | REAL(wp), PARAMETER :: rz0_i_s_0 = 0.69e-3_wp ! Eq.(43) of Lupkes & Gryanik (2015) [m] => to estimate CdN10 for skin drag! |
---|
| 33 | REAL(wp), PARAMETER :: rz0_i_f_0 = 4.54e-4_wp ! bottom p.562 MIZ [m] (LG15) |
---|
| 34 | |
---|
| 35 | !!---------------------------------------------------------------------- |
---|
| 36 | CONTAINS |
---|
| 37 | |
---|
| 38 | SUBROUTINE turb_ice_lu12( zt, zu, Ts_i, t_zt, qs_i, q_zt, U_zu, frice, & |
---|
| 39 | & Cd_i, Ch_i, Ce_i, t_zu_i, q_zu_i, & |
---|
| 40 | & CdN, ChN, CeN, xz0, xu_star, xL, xUN10 ) |
---|
| 41 | !!---------------------------------------------------------------------- |
---|
| 42 | !! *** ROUTINE turb_ice_lu12 *** |
---|
| 43 | !! |
---|
| 44 | !! ** Purpose : Computes turbulent transfert coefficients of surface |
---|
| 45 | !! fluxes according to: |
---|
| 46 | !! Lüpkes, C., Gryanik, V. M., Hartmann, J., and Andreas, E. L. ( 2012), |
---|
| 47 | !! A parametrization, based on sea ice morphology, of the neutral |
---|
| 48 | !! atmospheric drag coefficients for weather prediction and climate models, |
---|
| 49 | !! J. Geophys. Res., 117, D13112, doi:10.1029/2012JD017630. |
---|
| 50 | !! |
---|
| 51 | !! INPUT : |
---|
| 52 | !! ------- |
---|
| 53 | !! * zt : height for temperature and spec. hum. of air [m] |
---|
| 54 | !! * zu : height for wind speed (usually 10m) [m] |
---|
| 55 | !! * Ts_i : surface temperature of sea-ice [K] |
---|
| 56 | !! * t_zt : potential air temperature at zt [K] |
---|
| 57 | !! * qs_i : saturation specific humidity at temp. Ts_i over ice [kg/kg] |
---|
| 58 | !! * q_zt : specific humidity of air at zt [kg/kg] |
---|
| 59 | !! * U_zu : scalar wind speed at zu [m/s] |
---|
| 60 | !! * frice : sea-ice concentration (fraction) |
---|
| 61 | !! |
---|
| 62 | !! OUTPUT : |
---|
| 63 | !! -------- |
---|
| 64 | !! * Cd_i : drag coefficient over sea-ice |
---|
| 65 | !! * Ch_i : sensible heat coefficient over sea-ice |
---|
| 66 | !! * Ce_i : sublimation coefficient over sea-ice |
---|
| 67 | !! * t_zu_i : pot. air temp. adjusted at zu over sea-ice [K] |
---|
| 68 | !! * q_zu_i : spec. hum. of air adjusted at zu over sea-ice [kg/kg] |
---|
| 69 | !! |
---|
| 70 | !! OPTIONAL OUTPUT: |
---|
| 71 | !! ---------------- |
---|
| 72 | !! * CdN : neutral-stability drag coefficient |
---|
| 73 | !! * ChN : neutral-stability sensible heat coefficient |
---|
| 74 | !! * CeN : neutral-stability evaporation coefficient |
---|
| 75 | !! * xz0 : return the aerodynamic roughness length (integration constant for wind stress) [m] |
---|
| 76 | !! * xu_star : return u* the friction velocity [m/s] |
---|
| 77 | !! * xL : return the Obukhov length [m] |
---|
| 78 | !! * xUN10 : neutral wind speed at 10m [m/s] |
---|
| 79 | !! |
---|
| 80 | !! ** Author: L. Brodeau, January 2020 / AeroBulk (https://github.com/brodeau/aerobulk/) |
---|
| 81 | !!---------------------------------------------------------------------------------- |
---|
| 82 | REAL(wp), INTENT(in ) :: zt ! height for t_zt and q_zt [m] |
---|
| 83 | REAL(wp), INTENT(in ) :: zu ! height for U_zu [m] |
---|
| 84 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: Ts_i ! ice surface temperature [Kelvin] |
---|
| 85 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: t_zt ! potential air temperature [Kelvin] |
---|
| 86 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: qs_i ! sat. spec. hum. at ice/air interface [kg/kg] |
---|
| 87 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: q_zt ! spec. air humidity at zt [kg/kg] |
---|
| 88 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: U_zu ! relative wind module at zu [m/s] |
---|
| 89 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: frice ! sea-ice concentration (fraction) |
---|
| 90 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj) :: Cd_i ! drag coefficient over sea-ice |
---|
| 91 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj) :: Ch_i ! transfert coefficient for heat over ice |
---|
| 92 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj) :: Ce_i ! transfert coefficient for sublimation over ice |
---|
| 93 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj) :: t_zu_i ! pot. air temp. adjusted at zu [K] |
---|
| 94 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj) :: q_zu_i ! spec. humidity adjusted at zu [kg/kg] |
---|
| 95 | !!---------------------------------------------------------------------------------- |
---|
| 96 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj), OPTIONAL :: CdN |
---|
| 97 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj), OPTIONAL :: ChN |
---|
| 98 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj), OPTIONAL :: CeN |
---|
| 99 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj), OPTIONAL :: xz0 ! Aerodynamic roughness length [m] |
---|
| 100 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj), OPTIONAL :: xu_star ! u*, friction velocity |
---|
| 101 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj), OPTIONAL :: xL ! zeta (zu/L) |
---|
| 102 | REAL(wp), INTENT(out), DIMENSION(jpi,jpj), OPTIONAL :: xUN10 ! Neutral wind at zu |
---|
| 103 | !!---------------------------------------------------------------------------------- |
---|
[13830] | 104 | REAL(wp), DIMENSION(:,:), ALLOCATABLE :: dt_zu, dq_zu, z0 |
---|
[13655] | 105 | REAL(wp), DIMENSION(:,:), ALLOCATABLE :: Ubzu |
---|
| 106 | !! |
---|
| 107 | LOGICAL :: lreturn_cdn=.FALSE., lreturn_chn=.FALSE., lreturn_cen=.FALSE. |
---|
| 108 | LOGICAL :: lreturn_z0=.FALSE., lreturn_ustar=.FALSE., lreturn_L=.FALSE., lreturn_UN10=.FALSE. |
---|
| 109 | !! |
---|
| 110 | CHARACTER(len=40), PARAMETER :: crtnm = 'turb_ice_lu12@sbcblk_algo_ice_lu12.f90' |
---|
| 111 | !!---------------------------------------------------------------------------------- |
---|
| 112 | ALLOCATE ( Ubzu(jpi,jpj) ) |
---|
[13830] | 113 | ALLOCATE ( dt_zu(jpi,jpj), dq_zu(jpi,jpj), z0(jpi,jpj) ) |
---|
[13655] | 114 | |
---|
| 115 | lreturn_cdn = PRESENT(CdN) |
---|
| 116 | lreturn_chn = PRESENT(ChN) |
---|
| 117 | lreturn_cen = PRESENT(CeN) |
---|
| 118 | lreturn_z0 = PRESENT(xz0) |
---|
| 119 | lreturn_ustar = PRESENT(xu_star) |
---|
| 120 | lreturn_L = PRESENT(xL) |
---|
| 121 | lreturn_UN10 = PRESENT(xUN10) |
---|
| 122 | |
---|
| 123 | !! Scalar wind speed cannot be below 0.2 m/s |
---|
| 124 | Ubzu = MAX( U_zu, wspd_thrshld_ice ) |
---|
| 125 | |
---|
| 126 | !! First guess of temperature and humidity at height zu: |
---|
| 127 | t_zu_i = MAX( t_zt , 100._wp ) ! who knows what's given on masked-continental regions... |
---|
| 128 | q_zu_i = MAX( q_zt , 0.1e-6_wp ) ! " |
---|
| 129 | |
---|
| 130 | !! Air-Ice & Air-Sea differences (and we don't want them to be 0!) |
---|
| 131 | dt_zu = t_zu_i - Ts_i ; dt_zu = SIGN( MAX(ABS(dt_zu),1.E-6_wp), dt_zu ) |
---|
| 132 | dq_zu = q_zu_i - qs_i ; dq_zu = SIGN( MAX(ABS(dq_zu),1.E-9_wp), dq_zu ) |
---|
| 133 | |
---|
| 134 | !! To estimate CDN10_skin: |
---|
| 135 | !! we use the method that comes in LG15, i.e. by starting from a default roughness length z0 for skin drag: |
---|
| 136 | |
---|
| 137 | Ce_i(:,:) = rz0_i_s_0 !! temporary array to contain roughness length for skin drag ! |
---|
| 138 | |
---|
| 139 | |
---|
| 140 | !! Method #1: |
---|
| 141 | !Cd_i(:,:) = Cd_from_z0( zu, Ce_i(:,:) ) + CdN10_f_LU13( frice(:,:) ) |
---|
| 142 | !IF( lreturn_cdfrm ) CdN_frm = CdN10_f_LU13( frice(:,:) ) |
---|
| 143 | !PRINT *, 'LOLO: estimate of Cd_f_i method #1 =>', CdN10_f_LU13( frice(:,:) ); PRINT *, '' |
---|
| 144 | |
---|
| 145 | !! Method #2: |
---|
| 146 | !! We need an estimate of z0 over water: |
---|
| 147 | !z0_w(:,:) = z0_from_Cd( zu, CD_N10_NCAR(Ubzu) ) |
---|
| 148 | !!PRINT *, 'LOLO: estimate of z0_w =>', z0_w |
---|
| 149 | !Cd_i(:,:) = Cd_from_z0( zu, Ce_i(:,:) ) + CdN10_f_LU12( frice(:,:), z0_w(:,:) ) |
---|
| 150 | !IF( lreturn_cdfrm ) CdN_frm = CdN10_f_LU12( frice(:,:), z0_w(:,:) ) |
---|
| 151 | !! N10 skin drag N10 form drag |
---|
| 152 | |
---|
| 153 | !! Method #3: |
---|
| 154 | !Cd_i(:,:) = Cd_from_z0( zu, Ce_i(:,:) ) + CdN10_f_LU12_eq36( frice(:,:) ) |
---|
| 155 | !IF( lreturn_cdfrm ) CdN_frm = CdN10_f_LU12_eq36( frice(:,:) ) |
---|
| 156 | !PRINT *, 'LOLO: estimate of Cd_f_i method #2 =>', CdN10_f_LU12( frice(:,:), z0_w(:,:) ) |
---|
| 157 | |
---|
| 158 | !! Method #4: |
---|
| 159 | !! using eq.21 of LG15 instead: |
---|
[13830] | 160 | z0(:,:) = rz0_i_f_0 |
---|
| 161 | !Cd_i(:,:) = Cd_from_z0( zu, Ce_i(:,:) ) + CdN_f_LG15( zu, frice(:,:), z0(:,:) ) / frice(:,:) |
---|
| 162 | Cd_i(:,:) = Cd_from_z0( zu, Ce_i(:,:) ) + CdN_f_LG15( zu, frice(:,:), z0(:,:) ) !/ frice(:,:) |
---|
| 163 | !IF( lreturn_cdfrm ) CdN_frm = CdN_f_LG15( zu, frice(:,:), z0(:,:) ) |
---|
[13655] | 164 | |
---|
| 165 | |
---|
| 166 | Ch_i(:,:) = Cd_i(:,:) |
---|
| 167 | Ce_i(:,:) = Cd_i(:,:) |
---|
| 168 | |
---|
| 169 | IF( lreturn_cdn ) CdN = Cd_i(:,:) |
---|
| 170 | IF( lreturn_chn ) ChN = Ch_i(:,:) |
---|
| 171 | IF( lreturn_cen ) CeN = Ce_i(:,:) |
---|
| 172 | |
---|
| 173 | IF( lreturn_z0 ) xz0 = z0_from_Cd( zu, Cd_i ) |
---|
| 174 | IF( lreturn_ustar ) xu_star = SQRT(Cd_i)*Ubzu |
---|
| 175 | IF( lreturn_L ) xL = 1./One_on_L(t_zu_i, q_zu_i, SQRT(Cd_i)*Ubzu, & |
---|
| 176 | & Cd_i/SQRT(Cd_i)*dt_zu, Cd_i/SQRT(Cd_i)*dq_zu) |
---|
| 177 | IF( lreturn_UN10 ) xUN10 = SQRT(Cd_i)*Ubzu/vkarmn * LOG( 10._wp / z0_from_Cd( zu, Cd_i ) ) |
---|
| 178 | |
---|
[13830] | 179 | DEALLOCATE ( dt_zu, dq_zu, z0 ) |
---|
[13655] | 180 | DEALLOCATE ( Ubzu ) |
---|
| 181 | |
---|
| 182 | END SUBROUTINE turb_ice_lu12 |
---|
| 183 | |
---|
| 184 | !!====================================================================== |
---|
| 185 | END MODULE sbcblk_algo_ice_lu12 |
---|