[6723] | 1 | MODULE sbcblk_algo_ncar |
---|
| 2 | !!====================================================================== |
---|
| 3 | !! *** MODULE sbcblk_algo_ncar *** |
---|
| 4 | !! Computes: |
---|
| 5 | !! * bulk transfer coefficients C_D, C_E and C_H |
---|
| 6 | !! * air temp. and spec. hum. adjusted from zt (2m) to zu (10m) if needed |
---|
| 7 | !! * the effective bulk wind speed at 10m U_blk |
---|
| 8 | !! => all these are used in bulk formulas in sbcblk.F90 |
---|
| 9 | !! |
---|
| 10 | !! Using the bulk formulation/param. of Large & Yeager 2008 |
---|
| 11 | !! |
---|
| 12 | !! Routine turb_ncar maintained and developed in AeroBulk |
---|
[13017] | 13 | !! (https://github.com/brodeau/aerobulk/) |
---|
[6723] | 14 | !! |
---|
[13017] | 15 | !! L. Brodeau, 2020 |
---|
[6723] | 16 | !!===================================================================== |
---|
[13017] | 17 | !! History : 4.0 ! 2020-06 (L.Brodeau) successor of old turb_ncar of former sbcblk_core.F90 |
---|
[6723] | 18 | !!---------------------------------------------------------------------- |
---|
| 19 | |
---|
| 20 | !!---------------------------------------------------------------------- |
---|
| 21 | !! turb_ncar : computes the bulk turbulent transfer coefficients |
---|
| 22 | !! adjusts t_air and q_air from zt to zu m |
---|
| 23 | !! returns the effective bulk wind speed at 10m |
---|
| 24 | !!---------------------------------------------------------------------- |
---|
| 25 | USE oce ! ocean dynamics and tracers |
---|
| 26 | USE dom_oce ! ocean space and time domain |
---|
| 27 | USE phycst ! physical constants |
---|
| 28 | USE sbc_oce ! Surface boundary condition: ocean fields |
---|
| 29 | USE sbcwave, ONLY : cdn_wave ! wave module |
---|
[9570] | 30 | #if defined key_si3 || defined key_cice |
---|
[6723] | 31 | USE sbc_ice ! Surface boundary condition: ice fields |
---|
| 32 | #endif |
---|
| 33 | ! |
---|
| 34 | USE iom ! I/O manager library |
---|
| 35 | USE lib_mpp ! distribued memory computing library |
---|
| 36 | USE in_out_manager ! I/O manager |
---|
| 37 | USE prtctl ! Print control |
---|
| 38 | USE lib_fortran ! to use key_nosignedzero |
---|
| 39 | |
---|
| 40 | |
---|
| 41 | IMPLICIT NONE |
---|
| 42 | PRIVATE |
---|
| 43 | |
---|
[13017] | 44 | PUBLIC :: TURB_NCAR ! called by sbcblk.F90 |
---|
[6723] | 45 | |
---|
[6727] | 46 | ! ! NCAR own values for given constants: |
---|
[6723] | 47 | REAL(wp), PARAMETER :: rctv0 = 0.608 ! constant to obtain virtual temperature... |
---|
[13017] | 48 | |
---|
| 49 | INTEGER , PARAMETER :: nb_itt = 4 ! number of itterations |
---|
| 50 | |
---|
[6723] | 51 | !!---------------------------------------------------------------------- |
---|
| 52 | CONTAINS |
---|
| 53 | |
---|
| 54 | SUBROUTINE turb_ncar( zt, zu, sst, t_zt, ssq, q_zt, U_zu, & |
---|
[13017] | 55 | & Cd, Ch, Ce, t_zu, q_zu, Ub, & |
---|
| 56 | & CdN, ChN, CeN ) |
---|
| 57 | !!---------------------------------------------------------------------- |
---|
[6723] | 58 | !! *** ROUTINE turb_ncar *** |
---|
| 59 | !! |
---|
| 60 | !! ** Purpose : Computes turbulent transfert coefficients of surface |
---|
| 61 | !! fluxes according to Large & Yeager (2004) and Large & Yeager (2008) |
---|
| 62 | !! If relevant (zt /= zu), adjust temperature and humidity from height zt to zu |
---|
[13017] | 63 | !! Returns the effective bulk wind speed at zu to be used in the bulk formulas |
---|
[6723] | 64 | !! |
---|
| 65 | !! INPUT : |
---|
| 66 | !! ------- |
---|
| 67 | !! * zt : height for temperature and spec. hum. of air [m] |
---|
[13017] | 68 | !! * zu : height for wind speed (usually 10m) [m] |
---|
| 69 | !! * sst : bulk SST [K] |
---|
[6723] | 70 | !! * t_zt : potential air temperature at zt [K] |
---|
| 71 | !! * ssq : specific humidity at saturation at SST [kg/kg] |
---|
| 72 | !! * q_zt : specific humidity of air at zt [kg/kg] |
---|
[13017] | 73 | !! * U_zu : scalar wind speed at zu [m/s] |
---|
[6723] | 74 | !! |
---|
| 75 | !! OUTPUT : |
---|
| 76 | !! -------- |
---|
| 77 | !! * Cd : drag coefficient |
---|
| 78 | !! * Ch : sensible heat coefficient |
---|
| 79 | !! * Ce : evaporation coefficient |
---|
| 80 | !! * t_zu : pot. air temperature adjusted at wind height zu [K] |
---|
| 81 | !! * q_zu : specific humidity of air // [kg/kg] |
---|
[13017] | 82 | !! * Ub : bulk wind speed at zu [m/s] |
---|
| 83 | !! |
---|
| 84 | !! ** Author: L. Brodeau, June 2019 / AeroBulk (https://github.com/brodeau/aerobulk/) |
---|
[6723] | 85 | !!---------------------------------------------------------------------------------- |
---|
| 86 | REAL(wp), INTENT(in ) :: zt ! height for t_zt and q_zt [m] |
---|
| 87 | REAL(wp), INTENT(in ) :: zu ! height for U_zu [m] |
---|
| 88 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: sst ! sea surface temperature [Kelvin] |
---|
| 89 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: t_zt ! potential air temperature [Kelvin] |
---|
| 90 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: ssq ! sea surface specific humidity [kg/kg] |
---|
[13017] | 91 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: q_zt ! specific air humidity at zt [kg/kg] |
---|
[6723] | 92 | REAL(wp), INTENT(in ), DIMENSION(jpi,jpj) :: U_zu ! relative wind module at zu [m/s] |
---|
| 93 | REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: Cd ! transfer coefficient for momentum (tau) |
---|
| 94 | REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: Ch ! transfer coefficient for sensible heat (Q_sens) |
---|
| 95 | REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: Ce ! transfert coefficient for evaporation (Q_lat) |
---|
| 96 | REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: t_zu ! pot. air temp. adjusted at zu [K] |
---|
| 97 | REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: q_zu ! spec. humidity adjusted at zu [kg/kg] |
---|
[13017] | 98 | REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: Ub ! bulk wind speed at zu [m/s] |
---|
| 99 | REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: CdN, ChN, CeN ! neutral transfer coefficients |
---|
[6723] | 100 | ! |
---|
[13017] | 101 | INTEGER :: j_itt |
---|
| 102 | LOGICAL :: l_zt_equal_zu = .FALSE. ! if q and t are given at same height as U |
---|
[6723] | 103 | ! |
---|
[9125] | 104 | REAL(wp), DIMENSION(jpi,jpj) :: Cx_n10 ! 10m neutral latent/sensible coefficient |
---|
[13017] | 105 | REAL(wp), DIMENSION(jpi,jpj) :: sqrtCdN10 ! root square of Cd_n10 |
---|
[9125] | 106 | REAL(wp), DIMENSION(jpi,jpj) :: zeta_u ! stability parameter at height zu |
---|
| 107 | REAL(wp), DIMENSION(jpi,jpj) :: zpsi_h_u |
---|
| 108 | REAL(wp), DIMENSION(jpi,jpj) :: ztmp0, ztmp1, ztmp2 |
---|
[13017] | 109 | REAL(wp), DIMENSION(jpi,jpj) :: sqrtCd |
---|
[6723] | 110 | !!---------------------------------------------------------------------------------- |
---|
| 111 | |
---|
[13017] | 112 | l_zt_equal_zu = ( ABS(zu - zt) < 0.01_wp ) |
---|
[6723] | 113 | |
---|
[13017] | 114 | Ub = MAX( 0.5_wp , U_zu ) ! relative wind speed at zu (normally 10m), we don't want to fall under 0.5 m/s |
---|
[6723] | 115 | |
---|
[13017] | 116 | !! Neutral drag coefficient at zu: |
---|
[6723] | 117 | IF( ln_cdgw ) THEN ! wave drag case |
---|
[13017] | 118 | CdN = MAX( cdn_wave(:,:) + rsmall * ( 1._wp - tmask(:,:,1) ) , 0.1E-3_wp ) |
---|
[6723] | 119 | ELSE |
---|
[13017] | 120 | CdN = CD_N10_NCAR( Ub ) |
---|
[6723] | 121 | ENDIF |
---|
[13017] | 122 | sqrtCdN10 = SQRT( CdN ) |
---|
[6723] | 123 | |
---|
| 124 | !! Initializing transf. coeff. with their first guess neutral equivalents : |
---|
[13017] | 125 | Cd = CdN |
---|
| 126 | Ce = CE_N10_NCAR( sqrtCdN10 ) |
---|
| 127 | ztmp0 = 0.5_wp + SIGN(0.5_wp, virt_temp(t_zt, q_zt) - virt_temp(sst, ssq)) ! we guess stability based on delta of virt. pot. temp. |
---|
| 128 | Ch = CH_N10_NCAR( sqrtCdN10 , ztmp0 ) |
---|
| 129 | sqrtCd = sqrtCdN10 |
---|
[6723] | 130 | |
---|
| 131 | !! Initializing values at z_u with z_t values: |
---|
[13017] | 132 | t_zu = t_zt |
---|
| 133 | q_zu = q_zt |
---|
[6723] | 134 | |
---|
[13017] | 135 | !! ITERATION BLOCK |
---|
| 136 | DO j_itt = 1, nb_itt |
---|
[6723] | 137 | ! |
---|
| 138 | ztmp1 = t_zu - sst ! Updating air/sea differences |
---|
| 139 | ztmp2 = q_zu - ssq |
---|
| 140 | |
---|
[13017] | 141 | ! Updating turbulent scales : (L&Y 2004 Eq. (7)) |
---|
| 142 | ztmp0 = sqrtCd*Ub ! u* |
---|
| 143 | ztmp1 = Ch/sqrtCd*ztmp1 ! theta* |
---|
| 144 | ztmp2 = Ce/sqrtCd*ztmp2 ! q* |
---|
[6723] | 145 | |
---|
[13017] | 146 | ! Estimate the inverse of Obukov length (1/L) at height zu: |
---|
| 147 | ztmp0 = One_on_L( t_zu, q_zu, ztmp0, ztmp1, ztmp2 ) |
---|
[6723] | 148 | |
---|
| 149 | !! Stability parameters : |
---|
[13017] | 150 | zeta_u = zu*ztmp0 |
---|
| 151 | zeta_u = sign( min(abs(zeta_u),10._wp), zeta_u ) |
---|
[6723] | 152 | |
---|
[13017] | 153 | !! Shifting temperature and humidity at zu (L&Y 2004 Eq. (9b-9c)) |
---|
[6723] | 154 | IF( .NOT. l_zt_equal_zu ) THEN |
---|
[13017] | 155 | ztmp0 = zt*ztmp0 ! zeta_t ! |
---|
| 156 | ztmp0 = SIGN( MIN(ABS(ztmp0),10._wp), ztmp0 ) ! Temporaty array ztmp0 == zeta_t !!! |
---|
| 157 | ztmp0 = LOG(zt/zu) + psi_h_ncar(zeta_u) - psi_h_ncar(ztmp0) ! ztmp0 just used as temp array again! |
---|
| 158 | t_zu = t_zt - ztmp1/vkarmn*ztmp0 ! ztmp1 is still theta* L&Y 2004 Eq. (9b) |
---|
| 159 | !! |
---|
| 160 | q_zu = q_zt - ztmp2/vkarmn*ztmp0 ! ztmp2 is still q* L&Y 2004 Eq. (9c) |
---|
| 161 | q_zu = MAX(0._wp, q_zu) |
---|
[6723] | 162 | END IF |
---|
| 163 | |
---|
[13017] | 164 | ! Update neutral wind speed at 10m and neutral Cd at 10m (L&Y 2004 Eq. 9a)... |
---|
| 165 | ! In very rare low-wind conditions, the old way of estimating the |
---|
| 166 | ! neutral wind speed at 10m leads to a negative value that causes the code |
---|
| 167 | ! to crash. To prevent this a threshold of 0.25m/s is imposed. |
---|
| 168 | ztmp2 = psi_m_ncar(zeta_u) |
---|
| 169 | ztmp0 = MAX( 0.25_wp , UN10_from_CD(zu, Ub, Cd, ppsi=ztmp2) ) ! U_n10 (ztmp2 == psi_m_ncar(zeta_u)) |
---|
[10190] | 170 | |
---|
[13017] | 171 | IF( ln_cdgw ) THEN ! wave drag case |
---|
| 172 | CdN = MAX( cdn_wave(:,:) + rsmall * ( 1._wp - tmask(:,:,1) ) , 0.1E-3_wp ) |
---|
[6723] | 173 | ELSE |
---|
[13017] | 174 | CdN = CD_N10_NCAR(ztmp0) ! Cd_n10 |
---|
| 175 | END IF |
---|
| 176 | sqrtCdN10 = SQRT(CdN) |
---|
[6723] | 177 | |
---|
[13017] | 178 | !! Update of transfer coefficients: |
---|
| 179 | ztmp1 = 1._wp + sqrtCdN10/vkarmn*(LOG(zu/10._wp) - ztmp2) ! L&Y 2004 Eq. (10a) (ztmp2 == psi_m(zeta_u)) |
---|
| 180 | Cd = MAX( CdN / ( ztmp1*ztmp1 ) , 0.1E-3_wp ) |
---|
| 181 | sqrtCd = SQRT( Cd ) |
---|
[6723] | 182 | |
---|
[13017] | 183 | ztmp0 = ( LOG(zu/10._wp) - psi_h_ncar(zeta_u) ) / vkarmn / sqrtCdN10 |
---|
| 184 | ztmp2 = sqrtCd / sqrtCdN10 |
---|
[6723] | 185 | |
---|
[13017] | 186 | ztmp1 = 0.5_wp + sign(0.5_wp,zeta_u) ! stability flag |
---|
| 187 | ChN = CH_N10_NCAR( sqrtCdN10 , ztmp1 ) |
---|
| 188 | ztmp1 = 1._wp + ChN*ztmp0 |
---|
| 189 | Ch = MAX( ChN*ztmp2 / ztmp1 , 0.1E-3_wp ) ! L&Y 2004 Eq. (10b) |
---|
[6723] | 190 | |
---|
[13017] | 191 | CeN = CE_N10_NCAR( sqrtCdN10 ) |
---|
| 192 | ztmp1 = 1._wp + CeN*ztmp0 |
---|
| 193 | Ce = MAX( CeN*ztmp2 / ztmp1 , 0.1E-3_wp ) ! L&Y 2004 Eq. (10c) |
---|
| 194 | |
---|
| 195 | END DO !DO j_itt = 1, nb_itt |
---|
| 196 | |
---|
[6723] | 197 | END SUBROUTINE turb_ncar |
---|
| 198 | |
---|
| 199 | |
---|
[13017] | 200 | FUNCTION CD_N10_NCAR( pw10 ) |
---|
| 201 | !!---------------------------------------------------------------------------------- |
---|
[6723] | 202 | !! Estimate of the neutral drag coefficient at 10m as a function |
---|
| 203 | !! of neutral wind speed at 10m |
---|
| 204 | !! |
---|
[13017] | 205 | !! Origin: Large & Yeager 2008, Eq. (11) |
---|
[6723] | 206 | !! |
---|
[13017] | 207 | !! ** Author: L. Brodeau, june 2016 / AeroBulk (https://github.com/brodeau/aerobulk/) |
---|
[6723] | 208 | !!---------------------------------------------------------------------------------- |
---|
| 209 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pw10 ! scalar wind speed at 10m (m/s) |
---|
[13017] | 210 | REAL(wp), DIMENSION(jpi,jpj) :: CD_N10_NCAR |
---|
[6723] | 211 | ! |
---|
| 212 | INTEGER :: ji, jj ! dummy loop indices |
---|
| 213 | REAL(wp) :: zgt33, zw, zw6 ! local scalars |
---|
| 214 | !!---------------------------------------------------------------------------------- |
---|
| 215 | ! |
---|
| 216 | DO jj = 1, jpj |
---|
| 217 | DO ji = 1, jpi |
---|
| 218 | ! |
---|
| 219 | zw = pw10(ji,jj) |
---|
| 220 | zw6 = zw*zw*zw |
---|
| 221 | zw6 = zw6*zw6 |
---|
| 222 | ! |
---|
| 223 | ! When wind speed > 33 m/s => Cyclone conditions => special treatment |
---|
[13017] | 224 | zgt33 = 0.5_wp + SIGN( 0.5_wp, (zw - 33._wp) ) ! If pw10 < 33. => 0, else => 1 |
---|
[6723] | 225 | ! |
---|
[13017] | 226 | CD_N10_NCAR(ji,jj) = 1.e-3_wp * ( & |
---|
| 227 | & (1._wp - zgt33)*( 2.7_wp/zw + 0.142_wp + zw/13.09_wp - 3.14807E-10_wp*zw6) & ! wind < 33 m/s |
---|
| 228 | & + zgt33 * 2.34_wp ) ! wind >= 33 m/s |
---|
[6723] | 229 | ! |
---|
[13017] | 230 | CD_N10_NCAR(ji,jj) = MAX( CD_N10_NCAR(ji,jj), 0.1E-3_wp ) |
---|
[6723] | 231 | ! |
---|
| 232 | END DO |
---|
| 233 | END DO |
---|
| 234 | ! |
---|
[13017] | 235 | END FUNCTION CD_N10_NCAR |
---|
[6723] | 236 | |
---|
| 237 | |
---|
[13017] | 238 | |
---|
| 239 | FUNCTION CH_N10_NCAR( psqrtcdn10 , pstab ) |
---|
[6723] | 240 | !!---------------------------------------------------------------------------------- |
---|
[13017] | 241 | !! Estimate of the neutral heat transfer coefficient at 10m !! |
---|
| 242 | !! Origin: Large & Yeager 2008, Eq. (9) and (12) |
---|
| 243 | |
---|
| 244 | !!---------------------------------------------------------------------------------- |
---|
| 245 | REAL(wp), DIMENSION(jpi,jpj) :: ch_n10_ncar |
---|
| 246 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: psqrtcdn10 ! sqrt( CdN10 ) |
---|
| 247 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pstab ! stable ABL => 1 / unstable ABL => 0 |
---|
| 248 | !!---------------------------------------------------------------------------------- |
---|
| 249 | ! |
---|
| 250 | ch_n10_ncar = MAX( 1.e-3_wp * psqrtcdn10*( 18._wp*pstab + 32.7_wp*(1._wp - pstab) ) , 0.1E-3_wp ) ! Eq. (9) & (12) Large & Yeager, 2008 |
---|
| 251 | ! |
---|
| 252 | END FUNCTION CH_N10_NCAR |
---|
| 253 | |
---|
| 254 | FUNCTION CE_N10_NCAR( psqrtcdn10 ) |
---|
| 255 | !!---------------------------------------------------------------------------------- |
---|
| 256 | !! Estimate of the neutral heat transfer coefficient at 10m !! |
---|
| 257 | !! Origin: Large & Yeager 2008, Eq. (9) and (13) |
---|
| 258 | !!---------------------------------------------------------------------------------- |
---|
| 259 | REAL(wp), DIMENSION(jpi,jpj) :: ce_n10_ncar |
---|
| 260 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: psqrtcdn10 ! sqrt( CdN10 ) |
---|
| 261 | !!---------------------------------------------------------------------------------- |
---|
| 262 | ce_n10_ncar = MAX( 1.e-3_wp * ( 34.6_wp * psqrtcdn10 ) , 0.1E-3_wp ) |
---|
| 263 | ! |
---|
| 264 | END FUNCTION CE_N10_NCAR |
---|
| 265 | |
---|
| 266 | |
---|
| 267 | FUNCTION psi_m_ncar( pzeta ) |
---|
| 268 | !!---------------------------------------------------------------------------------- |
---|
[6723] | 269 | !! Universal profile stability function for momentum |
---|
[13017] | 270 | !! !! Psis, L&Y 2004, Eq. (8c), (8d), (8e) |
---|
| 271 | !! |
---|
| 272 | !! pzeta : stability paramenter, z/L where z is altitude measurement |
---|
[6723] | 273 | !! and L is M-O length |
---|
| 274 | !! |
---|
[13017] | 275 | !! ** Author: L. Brodeau, June 2016 / AeroBulk (https://github.com/brodeau/aerobulk/) |
---|
[6723] | 276 | !!---------------------------------------------------------------------------------- |
---|
[13017] | 277 | REAL(wp), DIMENSION(jpi,jpj) :: psi_m_ncar |
---|
| 278 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pzeta |
---|
[6723] | 279 | ! |
---|
[13017] | 280 | INTEGER :: ji, jj ! dummy loop indices |
---|
| 281 | REAL(wp) :: zzeta, zx2, zx, zpsi_unst, zpsi_stab, zstab ! local scalars |
---|
[6723] | 282 | !!---------------------------------------------------------------------------------- |
---|
| 283 | DO jj = 1, jpj |
---|
| 284 | DO ji = 1, jpi |
---|
[13017] | 285 | |
---|
| 286 | zzeta = pzeta(ji,jj) |
---|
[6723] | 287 | ! |
---|
[13017] | 288 | zx2 = SQRT( ABS(1._wp - 16._wp*zzeta) ) ! (1 - 16z)^0.5 |
---|
| 289 | zx2 = MAX( zx2 , 1._wp ) |
---|
| 290 | zx = SQRT(zx2) ! (1 - 16z)^0.25 |
---|
| 291 | zpsi_unst = 2._wp*LOG( (1._wp + zx )*0.5_wp ) & |
---|
| 292 | & + LOG( (1._wp + zx2)*0.5_wp ) & |
---|
| 293 | & - 2._wp*ATAN(zx) + rpi*0.5_wp |
---|
[6723] | 294 | ! |
---|
[13017] | 295 | zpsi_stab = -5._wp*zzeta |
---|
| 296 | ! |
---|
| 297 | zstab = 0.5_wp + SIGN(0.5_wp, zzeta) ! zzeta > 0 => zstab = 1 |
---|
| 298 | ! |
---|
| 299 | psi_m_ncar(ji,jj) = zstab * zpsi_stab & ! (zzeta > 0) Stable |
---|
| 300 | & + (1._wp - zstab) * zpsi_unst ! (zzeta < 0) Unstable |
---|
| 301 | ! |
---|
[6723] | 302 | END DO |
---|
| 303 | END DO |
---|
[13017] | 304 | END FUNCTION psi_m_ncar |
---|
[6723] | 305 | |
---|
| 306 | |
---|
[13017] | 307 | FUNCTION psi_h_ncar( pzeta ) |
---|
[6723] | 308 | !!---------------------------------------------------------------------------------- |
---|
| 309 | !! Universal profile stability function for temperature and humidity |
---|
[13017] | 310 | !! !! Psis, L&Y 2004, Eq. (8c), (8d), (8e) |
---|
[6723] | 311 | !! |
---|
[13017] | 312 | !! pzeta : stability paramenter, z/L where z is altitude measurement |
---|
[6723] | 313 | !! and L is M-O length |
---|
| 314 | !! |
---|
[13017] | 315 | !! ** Author: L. Brodeau, June 2016 / AeroBulk (https://github.com/brodeau/aerobulk/) |
---|
[6723] | 316 | !!---------------------------------------------------------------------------------- |
---|
[13017] | 317 | REAL(wp), DIMENSION(jpi,jpj) :: psi_h_ncar |
---|
[6723] | 318 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pzeta |
---|
| 319 | ! |
---|
[13017] | 320 | INTEGER :: ji, jj ! dummy loop indices |
---|
| 321 | REAL(wp) :: zzeta, zx2, zpsi_unst, zpsi_stab, zstab ! local scalars |
---|
[6723] | 322 | !!---------------------------------------------------------------------------------- |
---|
| 323 | ! |
---|
| 324 | DO jj = 1, jpj |
---|
| 325 | DO ji = 1, jpi |
---|
| 326 | ! |
---|
[13017] | 327 | zzeta = pzeta(ji,jj) |
---|
[6723] | 328 | ! |
---|
[13017] | 329 | zx2 = SQRT( ABS(1._wp - 16._wp*zzeta) ) ! (1 -16z)^0.5 |
---|
| 330 | zx2 = MAX( zx2 , 1._wp ) |
---|
| 331 | zpsi_unst = 2._wp*LOG( 0.5_wp*(1._wp + zx2) ) |
---|
| 332 | ! |
---|
| 333 | zpsi_stab = -5._wp*zzeta |
---|
| 334 | ! |
---|
| 335 | zstab = 0.5_wp + SIGN(0.5_wp, zzeta) ! zzeta > 0 => zstab = 1 |
---|
| 336 | ! |
---|
| 337 | psi_h_ncar(ji,jj) = zstab * zpsi_stab & ! (zzeta > 0) Stable |
---|
| 338 | & + (1._wp - zstab) * zpsi_unst ! (zzeta < 0) Unstable |
---|
| 339 | ! |
---|
[6723] | 340 | END DO |
---|
| 341 | END DO |
---|
[13017] | 342 | END FUNCTION psi_h_ncar |
---|
| 343 | |
---|
| 344 | |
---|
| 345 | |
---|
| 346 | |
---|
| 347 | FUNCTION UN10_from_CD( pzu, pUb, pCd, ppsi ) |
---|
| 348 | !!---------------------------------------------------------------------------------- |
---|
| 349 | !! Provides the neutral-stability wind speed at 10 m |
---|
| 350 | !!---------------------------------------------------------------------------------- |
---|
| 351 | REAL(wp), DIMENSION(jpi,jpj) :: UN10_from_CD !: [m/s] |
---|
| 352 | REAL(wp), INTENT(in) :: pzu !: measurement heigh of bulk wind speed |
---|
| 353 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pUb !: bulk wind speed at height pzu m [m/s] |
---|
| 354 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pCd !: drag coefficient |
---|
| 355 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: ppsi !: "Psi_m(pzu/L)" stability correction profile for momentum [] |
---|
| 356 | !!---------------------------------------------------------------------------------- |
---|
| 357 | !! Reminder: UN10 = u*/vkarmn * log(10/z0) |
---|
| 358 | !! and: u* = sqrt(Cd) * Ub |
---|
| 359 | !! u*/vkarmn * log( 10 / z0 ) |
---|
| 360 | UN10_from_CD(:,:) = SQRT(pCd(:,:))*pUb/vkarmn * LOG( 10._wp / z0_from_Cd( pzu, pCd(:,:), ppsi=ppsi(:,:) ) ) |
---|
| 361 | !! |
---|
| 362 | END FUNCTION UN10_from_CD |
---|
| 363 | |
---|
| 364 | |
---|
| 365 | FUNCTION One_on_L( ptha, pqa, pus, pts, pqs ) |
---|
| 366 | !!------------------------------------------------------------------------ |
---|
| 367 | !! |
---|
| 368 | !! Evaluates the 1./(Obukhov length) from air temperature, |
---|
| 369 | !! air specific humidity, and frictional scales u*, t* and q* |
---|
| 370 | !! |
---|
| 371 | !! Author: L. Brodeau, June 2019 / AeroBulk |
---|
| 372 | !! (https://github.com/brodeau/aerobulk/) |
---|
| 373 | !!------------------------------------------------------------------------ |
---|
| 374 | REAL(wp), DIMENSION(jpi,jpj) :: One_on_L !: 1./(Obukhov length) [m^-1] |
---|
| 375 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: ptha !: reference potential temperature of air [K] |
---|
| 376 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pqa !: reference specific humidity of air [kg/kg] |
---|
| 377 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pus !: u*: friction velocity [m/s] |
---|
| 378 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pts, pqs !: \theta* and q* friction aka turb. scales for temp. and spec. hum. |
---|
[6723] | 379 | ! |
---|
[13017] | 380 | INTEGER :: ji, jj ! dummy loop indices |
---|
| 381 | REAL(wp) :: zqa ! local scalar |
---|
| 382 | !!------------------------------------------------------------------- |
---|
| 383 | ! |
---|
| 384 | DO jj = 1, jpj |
---|
| 385 | DO ji = 1, jpi |
---|
| 386 | ! |
---|
| 387 | zqa = (1._wp + rctv0*pqa(ji,jj)) |
---|
| 388 | ! |
---|
| 389 | ! The main concern is to know whether, the vertical turbulent flux of virtual temperature, < u' theta_v' > is estimated with: |
---|
| 390 | ! a/ -u* [ theta* (1 + 0.61 q) + 0.61 theta q* ] => this is the one that seems correct! chose this one! |
---|
| 391 | ! or |
---|
| 392 | ! b/ -u* [ theta* + 0.61 theta q* ] |
---|
| 393 | ! |
---|
| 394 | One_on_L(ji,jj) = grav*vkarmn*( pts(ji,jj)*zqa + rctv0*ptha(ji,jj)*pqs(ji,jj) ) & |
---|
| 395 | & / MAX( pus(ji,jj)*pus(ji,jj)*ptha(ji,jj)*zqa , 1.E-9_wp ) |
---|
| 396 | ! |
---|
| 397 | END DO |
---|
| 398 | END DO |
---|
| 399 | ! |
---|
| 400 | One_on_L = SIGN( MIN(ABS(One_on_L),200._wp), One_on_L ) ! (prevent FPE from stupid values over masked regions...) |
---|
| 401 | ! |
---|
| 402 | END FUNCTION One_on_L |
---|
[6723] | 403 | |
---|
[13017] | 404 | |
---|
| 405 | FUNCTION z0_from_Cd( pzu, pCd, ppsi ) |
---|
| 406 | REAL(wp), DIMENSION(jpi,jpj) :: z0_from_Cd !: roughness length [m] |
---|
| 407 | REAL(wp) , INTENT(in) :: pzu !: reference height zu [m] |
---|
| 408 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pCd !: (neutral or non-neutral) drag coefficient [] |
---|
| 409 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in), OPTIONAL :: ppsi !: "Psi_m(pzu/L)" stability correction profile for momentum [] |
---|
| 410 | !! |
---|
| 411 | !! If pCd is the NEUTRAL-STABILITY drag coefficient then ppsi must be 0 or not given |
---|
| 412 | !! If pCd is the drag coefficient (in stable or unstable conditions) then pssi must be provided |
---|
| 413 | !!---------------------------------------------------------------------------------- |
---|
| 414 | IF ( PRESENT(ppsi) ) THEN |
---|
| 415 | !! Cd provided is the actual Cd (not the neutral-stability CdN) : |
---|
| 416 | z0_from_Cd = pzu * EXP( - ( vkarmn/SQRT(pCd(:,:)) + ppsi(:,:) ) ) !LB: ok, double-checked! |
---|
| 417 | ELSE |
---|
| 418 | !! Cd provided is the neutral-stability Cd, aka CdN : |
---|
| 419 | z0_from_Cd = pzu * EXP( - vkarmn/SQRT(pCd(:,:)) ) !LB: ok, double-checked! |
---|
| 420 | END IF |
---|
| 421 | END FUNCTION z0_from_Cd |
---|
| 422 | |
---|
| 423 | FUNCTION virt_temp( pta, pqa ) |
---|
| 424 | REAL(wp), DIMENSION(jpi,jpj) :: virt_temp !: virtual temperature [K] |
---|
| 425 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pta !: absolute or potential air temperature [K] |
---|
| 426 | REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pqa !: specific humidity of air [kg/kg] |
---|
| 427 | virt_temp(:,:) = pta(:,:) * (1._wp + rctv0*pqa(:,:)) |
---|
| 428 | END FUNCTION virt_temp |
---|
| 429 | |
---|
[6723] | 430 | !!====================================================================== |
---|
| 431 | END MODULE sbcblk_algo_ncar |
---|