[3] | 1 | MODULE trasbc |
---|
| 2 | !!============================================================================== |
---|
| 3 | !! *** MODULE trasbc *** |
---|
| 4 | !! Ocean active tracers: surface boundary condition |
---|
| 5 | !!============================================================================== |
---|
[503] | 6 | !! History : 8.2 ! 98-10 (G. Madec, G. Roullet, M. Imbard) Original code |
---|
| 7 | !! 8.2 ! 01-02 (D. Ludicone) sea ice and free surface |
---|
| 8 | !! 8.5 ! 02-06 (G. Madec) F90: Free form and module |
---|
[3] | 9 | !!---------------------------------------------------------------------- |
---|
[503] | 10 | |
---|
| 11 | !!---------------------------------------------------------------------- |
---|
[3] | 12 | !! tra_sbc : update the tracer trend at ocean surface |
---|
| 13 | !!---------------------------------------------------------------------- |
---|
| 14 | USE oce ! ocean dynamics and active tracers |
---|
[888] | 15 | USE sbc_oce ! surface boundary condition: ocean |
---|
[3] | 16 | USE dom_oce ! ocean space domain variables |
---|
| 17 | USE phycst ! physical constant |
---|
[216] | 18 | USE traqsr ! solar radiation penetration |
---|
| 19 | USE trdmod ! ocean trends |
---|
| 20 | USE trdmod_oce ! ocean variables trends |
---|
[3] | 21 | USE in_out_manager ! I/O manager |
---|
[258] | 22 | USE prtctl ! Print control |
---|
[1938] | 23 | USE sbcrnf ! River runoff |
---|
| 24 | USE sbcmod ! ln_rnf |
---|
[3] | 25 | |
---|
| 26 | IMPLICIT NONE |
---|
| 27 | PRIVATE |
---|
| 28 | |
---|
[503] | 29 | PUBLIC tra_sbc ! routine called by step.F90 |
---|
[3] | 30 | |
---|
| 31 | !! * Substitutions |
---|
| 32 | # include "domzgr_substitute.h90" |
---|
| 33 | # include "vectopt_loop_substitute.h90" |
---|
| 34 | !!---------------------------------------------------------------------- |
---|
[247] | 35 | !! OPA 9.0 , LOCEAN-IPSL (2005) |
---|
[888] | 36 | !! $Id$ |
---|
[503] | 37 | !! Software governed by the CeCILL licence (modipsl/doc/NEMO_CeCILL.txt) |
---|
[3] | 38 | !!---------------------------------------------------------------------- |
---|
| 39 | |
---|
| 40 | CONTAINS |
---|
| 41 | |
---|
| 42 | SUBROUTINE tra_sbc ( kt ) |
---|
| 43 | !!---------------------------------------------------------------------- |
---|
| 44 | !! *** ROUTINE tra_sbc *** |
---|
| 45 | !! |
---|
| 46 | !! ** Purpose : Compute the tracer surface boundary condition trend of |
---|
| 47 | !! (flux through the interface, concentration/dilution effect) |
---|
| 48 | !! and add it to the general trend of tracer equations. |
---|
| 49 | !! |
---|
| 50 | !! ** Method : |
---|
[664] | 51 | !! Following Roullet and Madec (2000), the air-sea flux can be divided |
---|
| 52 | !! into three effects: (1) Fext, external forcing; |
---|
| 53 | !! (2) Fwi, concentration/dilution effect due to water exchanged |
---|
| 54 | !! at the surface by evaporation, precipitations and runoff (E-P-R); |
---|
| 55 | !! (3) Fwe, tracer carried with the water that is exchanged. |
---|
| 56 | !! |
---|
| 57 | !! Fext, flux through the air-sea interface for temperature and salt: |
---|
[3] | 58 | !! - temperature : heat flux q (w/m2). If penetrative solar |
---|
| 59 | !! radiation q is only the non solar part of the heat flux, the |
---|
| 60 | !! solar part is added in traqsr.F routine. |
---|
| 61 | !! ta = ta + q /(rau0 rcp e3t) for k=1 |
---|
| 62 | !! - salinity : no salt flux |
---|
[664] | 63 | !! |
---|
| 64 | !! The formulation for Fwb and Fwi vary according to the free |
---|
| 65 | !! surface formulation (linear or variable volume). |
---|
| 66 | !! * Linear free surface |
---|
| 67 | !! The surface freshwater flux modifies the ocean volume |
---|
[3] | 68 | !! and thus the concentration of a tracer and the temperature. |
---|
| 69 | !! First order of the effect of surface freshwater exchange |
---|
| 70 | !! for salinity, it can be neglected on temperature (especially |
---|
[664] | 71 | !! as the temperature of precipitations and runoffs is usually |
---|
| 72 | !! unknown). |
---|
[3] | 73 | !! - temperature : we assume that the temperature of both |
---|
| 74 | !! precipitations and runoffs is equal to the SST, thus there |
---|
| 75 | !! is no additional flux since in this case, the concentration |
---|
| 76 | !! dilution effect is balanced by the net heat flux associated |
---|
[664] | 77 | !! to the freshwater exchange (Fwe+Fwi=0): |
---|
| 78 | !! (Tp P - Te E) + SST (P-E) = 0 when Tp=Te=SST |
---|
[3] | 79 | !! - salinity : evaporation, precipitation and runoff |
---|
[664] | 80 | !! water has a zero salinity (Fwe=0), thus only Fwi remains: |
---|
[3] | 81 | !! sa = sa + emp * sn / e3t for k=1 |
---|
| 82 | !! where emp, the surface freshwater budget (evaporation minus |
---|
| 83 | !! precipitation minus runoff) given in kg/m2/s is divided |
---|
[1739] | 84 | !! by 1035 kg/m3 (density of ocena water) to obtain m/s. |
---|
[664] | 85 | !! Note: even though Fwe does not appear explicitly for |
---|
| 86 | !! temperature in this routine, the heat carried by the water |
---|
| 87 | !! exchanged through the surface is part of the total heat flux |
---|
| 88 | !! forcing and must be taken into account in the global heat |
---|
| 89 | !! balance). |
---|
| 90 | !! * nonlinear free surface (variable volume, lk_vvl) |
---|
| 91 | !! contrary to the linear free surface case, Fwi is properly |
---|
| 92 | !! taken into account by using the true layer thicknesses to |
---|
| 93 | !! calculate tracer content and advection. There is no need to |
---|
| 94 | !! deal with it in this routine. |
---|
| 95 | !! - temperature: Fwe=SST (P-E+R) is added to Fext. |
---|
| 96 | !! - salinity: Fwe = 0, there is no surface flux of salt. |
---|
[3] | 97 | !! |
---|
| 98 | !! ** Action : - Update the 1st level of (ta,sa) with the trend associated |
---|
| 99 | !! with the tracer surface boundary condition |
---|
| 100 | !! - save the trend it in ttrd ('key_trdtra') |
---|
[503] | 101 | !!---------------------------------------------------------------------- |
---|
| 102 | USE oce, ONLY : ztrdt => ua ! use ua as 3D workspace |
---|
| 103 | USE oce, ONLY : ztrds => va ! use va as 3D workspace |
---|
[3] | 104 | !! |
---|
[503] | 105 | INTEGER, INTENT(in) :: kt ! ocean time-step index |
---|
| 106 | !! |
---|
[1938] | 107 | INTEGER :: ji, jj, jk ! dummy loop indices |
---|
| 108 | REAL(wp) :: zta, zsa ! temporary scalars, adjustment to temperature and salinity |
---|
| 109 | REAL(wp) :: azta, azsa ! temporary scalars, calculations of automatic change to temp & sal due to vvl (done elsewhere) |
---|
| 110 | REAL(wp) :: zsrau, zse3t, zdep ! temporary scalars, 1/density, 1/height of box, 1/height of effected water column |
---|
| 111 | REAL(wp) :: dheat, dsalt ! total change of temperature and salinity |
---|
| 112 | REAL(wp) :: tot_sal1, tot_tmp1 |
---|
[3] | 113 | !!---------------------------------------------------------------------- |
---|
| 114 | |
---|
| 115 | IF( kt == nit000 ) THEN |
---|
| 116 | IF(lwp) WRITE(numout,*) |
---|
| 117 | IF(lwp) WRITE(numout,*) 'tra_sbc : TRAcer Surface Boundary Condition' |
---|
| 118 | IF(lwp) WRITE(numout,*) '~~~~~~~ ' |
---|
| 119 | ENDIF |
---|
| 120 | |
---|
[1739] | 121 | zsrau = 1. / rau0 ! initialization |
---|
[457] | 122 | #if defined key_zco |
---|
| 123 | zse3t = 1. / e3t_0(1) |
---|
[3] | 124 | #endif |
---|
| 125 | |
---|
[503] | 126 | IF( l_trdtra ) THEN ! Save ta and sa trends |
---|
| 127 | ztrdt(:,:,:) = ta(:,:,:) |
---|
| 128 | ztrds(:,:,:) = sa(:,:,:) |
---|
[216] | 129 | ENDIF |
---|
| 130 | |
---|
[3] | 131 | IF( .NOT.ln_traqsr ) qsr(:,:) = 0.e0 ! no solar radiation penetration |
---|
| 132 | |
---|
[1938] | 133 | ! Concentration dillution effect on (t,s) due to evapouration, precipitation and qns, but not river runoff |
---|
[3] | 134 | DO jj = 2, jpj |
---|
| 135 | DO ji = fs_2, fs_jpim1 ! vector opt. |
---|
[457] | 136 | #if ! defined key_zco |
---|
[3] | 137 | zse3t = 1. / fse3t(ji,jj,1) |
---|
| 138 | #endif |
---|
[592] | 139 | IF( lk_vvl) THEN |
---|
[1938] | 140 | zta = ro0cpr * qns(ji,jj) * zse3t & ! temperature : heat flux |
---|
| 141 | & - emp(ji,jj) * zsrau * tn(ji,jj,1) * zse3t ! & cooling/heating effet of EMP flux |
---|
[592] | 142 | zsa = 0.e0 ! No salinity concent./dilut. effect |
---|
| 143 | ELSE |
---|
[1938] | 144 | zta = ro0cpr * qns(ji,jj) * zse3t ! temperature : heat flux |
---|
| 145 | zsa = emps(ji,jj) * zsrau * sn(ji,jj,1) * zse3t ! salinity : concent./dilut. effect |
---|
[592] | 146 | ENDIF |
---|
| 147 | ta(ji,jj,1) = ta(ji,jj,1) + zta ! add the trend to the general tracer trend |
---|
[3] | 148 | sa(ji,jj,1) = sa(ji,jj,1) + zsa |
---|
| 149 | END DO |
---|
| 150 | END DO |
---|
[216] | 151 | |
---|
[1938] | 152 | IF ( ln_rnf ) THEN |
---|
| 153 | ! Concentration / dilution effect on (t,s) due to river runoff |
---|
| 154 | DO jj=1,jpj |
---|
| 155 | DO ji=1,jpi |
---|
| 156 | rnf_dep(ji,jj)=0 |
---|
| 157 | DO jk=1,rnf_mod_dep(ji,jj) ! recalculates rnf_dep to be the depth |
---|
| 158 | rnf_dep(ji,jj)=rnf_dep(ji,jj)+fse3t(ji,jj,jk) ! in metres to the bottom of the relevant grid box |
---|
| 159 | ENDDO |
---|
| 160 | zdep = 1. / rnf_dep(ji,jj) |
---|
| 161 | zse3t= 1. / fse3t(ji,jj,1) |
---|
| 162 | IF ( rnf_tmp(ji,jj) == -999 ) rnf_tmp(ji,jj)=tn(ji,jj,1) ! if not specified set runoff temp to be sst |
---|
| 163 | |
---|
| 164 | IF ( rnf(ji,jj) .gt. 0.0 ) THEN |
---|
| 165 | |
---|
| 166 | IF( lk_vvl) THEN |
---|
| 167 | !!!indirect flux, concentration or dilution effect |
---|
| 168 | !!!force a dilution effect in all levels; |
---|
| 169 | dheat=0.0 |
---|
| 170 | dsalt=0.0 |
---|
| 171 | DO jk=1, rnf_mod_dep(ji,jj) |
---|
| 172 | zta = -tn(ji,jj,jk) * rnf(ji,jj) * zsrau * zdep |
---|
| 173 | zsa = -sn(ji,jj,jk) * rnf(ji,jj) * zsrau * zdep |
---|
| 174 | ta(ji,jj,jk)=ta(ji,jj,jk)+zta |
---|
| 175 | sa(ji,jj,jk)=sa(ji,jj,jk)+zsa |
---|
| 176 | dheat=dheat+zta*fse3t(ji,jj,jk) |
---|
| 177 | dsalt=dsalt+zsa*fse3t(ji,jj,jk) |
---|
| 178 | ENDDO |
---|
| 179 | !!!negate this total change in heat and salt content from top level |
---|
| 180 | zta=-dheat*zse3t |
---|
| 181 | zsa=-dsalt*zse3t |
---|
| 182 | ta(ji,jj,1)=ta(ji,jj,1)+zta |
---|
| 183 | sa(ji,jj,1)=sa(ji,jj,1)+zsa |
---|
| 184 | |
---|
| 185 | !!!direct flux |
---|
| 186 | zta = rnf_tmp(ji,jj) * rnf(ji,jj) * zsrau * zdep |
---|
| 187 | zsa = rnf_sal(ji,jj) * rnf(ji,jj) * zsrau * zdep |
---|
| 188 | |
---|
| 189 | DO jk=1, rnf_mod_dep(ji,jj) |
---|
| 190 | ta(ji,jj,jk) = ta(ji,jj,jk) + zta |
---|
| 191 | sa(ji,jj,jk) = sa(ji,jj,jk) + zsa |
---|
| 192 | ENDDO |
---|
| 193 | |
---|
| 194 | ELSE |
---|
| 195 | DO jk=1, rnf_mod_dep(ji,jj) |
---|
| 196 | zta = ( rnf_tmp(ji,jj)-tn(ji,jj,jk) ) * rnf(ji,jj) * zsrau * zdep |
---|
| 197 | zsa = ( rnf_sal(ji,jj)-sn(ji,jj,jk) ) * rnf(ji,jj) * zsrau * zdep |
---|
| 198 | ta(ji,jj,jk) = ta(ji,jj,jk) + zta |
---|
| 199 | sa(ji,jj,jk) = sa(ji,jj,jk) + zsa |
---|
| 200 | ENDDO |
---|
| 201 | ENDIF |
---|
| 202 | |
---|
| 203 | ELSEIF (rnf(ji,jj) .lt. 0.) THEN !! for use in baltic when flow is out of domain, want no change in temp and sal |
---|
| 204 | |
---|
| 205 | IF( lk_vvl) THEN |
---|
| 206 | !calculate automatic adjustment to sal and temp due to dilution/concentraion effect |
---|
| 207 | azta = -tn(ji,jj,1) * rnf(ji,jj) * zsrau * zse3t |
---|
| 208 | azsa = -sn(ji,jj,1) * rnf(ji,jj) * zsrau * zse3t |
---|
| 209 | !!!negate this change in sal and temp |
---|
| 210 | ta(ji,jj,1)=ta(ji,jj,1)-azta |
---|
| 211 | sa(ji,jj,1)=sa(ji,jj,1)-azsa |
---|
| 212 | ENDIF |
---|
| 213 | |
---|
| 214 | ENDIF |
---|
| 215 | |
---|
| 216 | ENDDO |
---|
| 217 | ENDDO |
---|
| 218 | |
---|
| 219 | ENDIF |
---|
| 220 | |
---|
[503] | 221 | IF( l_trdtra ) THEN ! save the sbc trends for diagnostic |
---|
| 222 | ztrdt(:,:,:) = ta(:,:,:) - ztrdt(:,:,:) |
---|
| 223 | ztrds(:,:,:) = sa(:,:,:) - ztrds(:,:,:) |
---|
| 224 | CALL trd_mod(ztrdt, ztrds, jptra_trd_nsr, 'TRA', kt) |
---|
[216] | 225 | ENDIF |
---|
[503] | 226 | ! |
---|
| 227 | IF(ln_ctl) CALL prt_ctl( tab3d_1=ta, clinfo1=' sbc - Ta: ', mask1=tmask, & |
---|
| 228 | & tab3d_2=sa, clinfo2= ' Sa: ', mask2=tmask, clinfo3='tra' ) |
---|
| 229 | ! |
---|
[3] | 230 | END SUBROUTINE tra_sbc |
---|
| 231 | |
---|
| 232 | !!====================================================================== |
---|
| 233 | END MODULE trasbc |
---|