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sbcblk.F90 in branches/2017/dev_merge_2017/NEMOGCM/NEMO/OPA_SRC/SBC – NEMO

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source: branches/2017/dev_merge_2017/NEMOGCM/NEMO/OPA_SRC/SBC/sbcblk.F90 @ 9098

Last change on this file since 9098 was 9098, checked in by flavoni, 6 years ago
change lbc_lnk in lbc_lnk_multi
File size: 72.1 KB

Line
1	MODULE sbcblk
2	!!======================================================================
3	!! * MODULE sbcblk *
4	!! Ocean forcing: momentum, heat and freshwater flux formulation
5	!! Aerodynamic Bulk Formulas
6	!! SUCCESSOR OF "sbcblk_core"
7	!!=====================================================================
8	!! History : 1.0 ! 2004-08 (U. Schweckendiek) Original CORE code
9	!! 2.0 ! 2005-04 (L. Brodeau, A.M. Treguier) improved CORE bulk and its user interface
10	!! 3.0 ! 2006-06 (G. Madec) sbc rewritting
11	!! - ! 2006-12 (L. Brodeau) Original code for turb_core
12	!! 3.2 ! 2009-04 (B. Lemaire) Introduce iom_put
13	!! 3.3 ! 2010-10 (S. Masson) add diurnal cycle
14	!! 3.4 ! 2011-11 (C. Harris) Fill arrays required by CICE
15	!! 3.7 ! 2014-06 (L. Brodeau) simplification and optimization of CORE bulk
16	!! 4.0 ! 2016-06 (L. Brodeau) sbcblk_core becomes sbcblk and is not restricted to the CORE algorithm anymore
17	!! ! ==> based on AeroBulk (http://aerobulk.sourceforge.net/)
18	!! 4.0 ! 2016-10 (G. Madec) introduce a sbc_blk_init routine
19	!! 4.0 ! 2016-10 (M. Vancoppenolle) Introduce Jules emulator (M. Vancoppenolle)
20	!!----------------------------------------------------------------------
21
22	!!----------------------------------------------------------------------
23	!! sbc_blk_init : initialisation of the chosen bulk formulation as ocean surface boundary condition
24	!! sbc_blk : bulk formulation as ocean surface boundary condition
25	!! blk_oce : computes momentum, heat and freshwater fluxes over ocean
26	!! rho_air : density of (moist) air (depends on T_air, q_air and SLP
27	!! cp_air : specific heat of (moist) air (depends spec. hum. q_air)
28	!! q_sat : saturation humidity as a function of SLP and temperature
29	!! L_vap : latent heat of vaporization of water as a function of temperature
30	!! sea-ice case only :
31	!! blk_ice_tau : provide the air-ice stress
32	!! blk_ice_flx : provide the heat and mass fluxes at air-ice interface
33	!! blk_ice_qcn : provide ice surface temperature and snow/ice conduction flux (emulating JULES coupler)
34	!! Cdn10_Lupkes2012 : Lupkes et al. (2012) air-ice drag
35	!! Cdn10_Lupkes2015 : Lupkes et al. (2015) air-ice drag
36	!!----------------------------------------------------------------------
37	USE oce ! ocean dynamics and tracers
38	USE dom_oce ! ocean space and time domain
39	USE phycst ! physical constants
40	USE fldread ! read input fields
41	USE sbc_oce ! Surface boundary condition: ocean fields
42	USE cyclone ! Cyclone 10m wind form trac of cyclone centres
43	USE sbcdcy ! surface boundary condition: diurnal cycle
44	USE sbcwave , ONLY : cdn_wave ! wave module
45	USE sbc_ice ! Surface boundary condition: ice fields
46	USE lib_fortran ! to use key_nosignedzero
47	#if defined key_lim3
48	USE ice , ONLY : u_ice, v_ice, jpl, a_i_b, at_i_b, tm_su, rn_cnd_s
49	USE icethd_dh ! for CALL ice_thd_snwblow
50	#endif
51	USE sbcblk_algo_ncar ! => turb_ncar : NCAR - CORE (Large & Yeager, 2009)
52	USE sbcblk_algo_coare ! => turb_coare : COAREv3.0 (Fairall et al. 2003)
53	USE sbcblk_algo_coare3p5 ! => turb_coare3p5 : COAREv3.5 (Edson et al. 2013)
54	USE sbcblk_algo_ecmwf ! => turb_ecmwf : ECMWF (IFS cycle 31)
55	!
56	USE iom ! I/O manager library
57	USE in_out_manager ! I/O manager
58	USE lib_mpp ! distribued memory computing library
59	USE timing ! Timing
60	USE lbclnk ! ocean lateral boundary conditions (or mpp link)
61	USE prtctl ! Print control
62
63	IMPLICIT NONE
64	PRIVATE
65
66	PUBLIC sbc_blk_init ! called in sbcmod
67	PUBLIC sbc_blk ! called in sbcmod
68	#if defined key_lim3
69	PUBLIC blk_ice_tau ! routine called in iceforcing
70	PUBLIC blk_ice_flx ! routine called in iceforcing
71	PUBLIC blk_ice_qcn ! routine called in iceforcing
72	#endif
73
74	!!Lolo: should ultimately be moved in the module with all physical constants ?
75	!!gm : In principle, yes.
76	REAL(wp), PARAMETER :: Cp_dry = 1005.0 !: Specic heat of dry air, constant pressure [J/K/kg]
77	REAL(wp), PARAMETER :: Cp_vap = 1860.0 !: Specic heat of water vapor, constant pressure [J/K/kg]
78	REAL(wp), PARAMETER :: R_dry = 287.05_wp !: Specific gas constant for dry air [J/K/kg]
79	REAL(wp), PARAMETER :: R_vap = 461.495_wp !: Specific gas constant for water vapor [J/K/kg]
80	REAL(wp), PARAMETER :: reps0 = R_dry/R_vap !: ratio of gas constant for dry air and water vapor => ~ 0.622
81	REAL(wp), PARAMETER :: rctv0 = R_vap/R_dry !: for virtual temperature (== (1-eps)/eps) => ~ 0.608
82
83	INTEGER , PARAMETER :: jpfld =10 ! maximum number of files to read
84	INTEGER , PARAMETER :: jp_wndi = 1 ! index of 10m wind velocity (i-component) (m/s) at T-point
85	INTEGER , PARAMETER :: jp_wndj = 2 ! index of 10m wind velocity (j-component) (m/s) at T-point
86	INTEGER , PARAMETER :: jp_tair = 3 ! index of 10m air temperature (Kelvin)
87	INTEGER , PARAMETER :: jp_humi = 4 ! index of specific humidity ( % )
88	INTEGER , PARAMETER :: jp_qsr = 5 ! index of solar heat (W/m2)
89	INTEGER , PARAMETER :: jp_qlw = 6 ! index of Long wave (W/m2)
90	INTEGER , PARAMETER :: jp_prec = 7 ! index of total precipitation (rain+snow) (Kg/m2/s)
91	INTEGER , PARAMETER :: jp_snow = 8 ! index of snow (solid prcipitation) (kg/m2/s)
92	INTEGER , PARAMETER :: jp_slp = 9 ! index of sea level pressure (Pa)
93	INTEGER , PARAMETER :: jp_tdif =10 ! index of tau diff associated to HF tau (N/m2) at T-point
94
95	TYPE(FLD), ALLOCATABLE, DIMENSION(:) :: sf ! structure of input fields (file informations, fields read)
96
97	! !!! Bulk parameters
98	REAL(wp), PARAMETER :: cpa = 1000.5 ! specific heat of air (only used for ice fluxes now...)
99	REAL(wp), PARAMETER :: Ls = 2.839e6 ! latent heat of sublimation
100	REAL(wp), PARAMETER :: Stef = 5.67e-8 ! Stefan Boltzmann constant
101	REAL(wp), PARAMETER :: Cd_ice = 1.4e-3 ! transfer coefficient over ice
102	REAL(wp), PARAMETER :: albo = 0.066 ! ocean albedo assumed to be constant
103	!
104	! !!* Namelist namsbc_blk : bulk parameters
105	LOGICAL :: ln_NCAR ! "NCAR" algorithm (Large and Yeager 2008)
106	LOGICAL :: ln_COARE_3p0 ! "COARE 3.0" algorithm (Fairall et al. 2003)
107	LOGICAL :: ln_COARE_3p5 ! "COARE 3.5" algorithm (Edson et al. 2013)
108	LOGICAL :: ln_ECMWF ! "ECMWF" algorithm (IFS cycle 31)
109	!
110	LOGICAL :: ln_taudif ! logical flag to use the "mean of stress module - module of mean stress" data
111	REAL(wp) :: rn_pfac ! multiplication factor for precipitation
112	REAL(wp) :: rn_efac ! multiplication factor for evaporation
113	REAL(wp) :: rn_vfac ! multiplication factor for ice/ocean velocity in the calculation of wind stress
114	REAL(wp) :: rn_zqt ! z(q,t) : height of humidity and temperature measurements
115	REAL(wp) :: rn_zu ! z(u) : height of wind measurements
116	!!gm ref namelist initialize it so remove the setting to false below
117	LOGICAL :: ln_Cd_L12 = .FALSE. ! Modify the drag ice-atm depending on ice concentration (from Lupkes et al. JGR2012)
118	LOGICAL :: ln_Cd_L15 = .FALSE. ! Modify the drag ice-atm depending on ice concentration (from Lupkes et al. JGR2015)
119	!
120	REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: Cd_atm ! transfer coefficient for momentum (tau)
121	REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: Ch_atm ! transfer coefficient for sensible heat (Q_sens)
122	REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: Ce_atm ! tansfert coefficient for evaporation (Q_lat)
123	REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: t_zu ! air temperature at wind speed height (needed by Lupkes 2015 bulk scheme)
124	REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: q_zu ! air spec. hum. at wind speed height (needed by Lupkes 2015 bulk scheme)
125	REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: cdn_oce, chn_oce, cen_oce ! needed by Lupkes 2015 bulk scheme
126
127	INTEGER :: nblk ! choice of the bulk algorithm
128	! ! associated indices:
129	INTEGER, PARAMETER :: np_NCAR = 1 ! "NCAR" algorithm (Large and Yeager 2008)
130	INTEGER, PARAMETER :: np_COARE_3p0 = 2 ! "COARE 3.0" algorithm (Fairall et al. 2003)
131	INTEGER, PARAMETER :: np_COARE_3p5 = 3 ! "COARE 3.5" algorithm (Edson et al. 2013)
132	INTEGER, PARAMETER :: np_ECMWF = 4 ! "ECMWF" algorithm (IFS cycle 31)
133
134	!! * Substitutions
135	# include "vectopt_loop_substitute.h90"
136	!!----------------------------------------------------------------------
137	!! NEMO/OPA 3.7 , NEMO-consortium (2014)
138	!! $Id: sbcblk.F90 6416 2016-04-01 12:22:17Z clem $
139	!! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt)
140	!!----------------------------------------------------------------------
141	CONTAINS
142
143	INTEGER FUNCTION sbc_blk_alloc()
144	!!-------------------------------------------------------------------
145	!! * ROUTINE sbc_blk_alloc *
146	!!-------------------------------------------------------------------
147	ALLOCATE( Cd_atm (jpi,jpj), Ch_atm (jpi,jpj), Ce_atm (jpi,jpj), t_zu(jpi,jpj), q_zu(jpi,jpj), &
148	& cdn_oce(jpi,jpj), chn_oce(jpi,jpj), cen_oce(jpi,jpj), STAT=sbc_blk_alloc )
149	!
150	IF( lk_mpp ) CALL mpp_sum ( sbc_blk_alloc )
151	IF( sbc_blk_alloc /= 0 ) CALL ctl_warn('sbc_blk_alloc: failed to allocate arrays')
152	END FUNCTION sbc_blk_alloc
153
154
155	SUBROUTINE sbc_blk_init
156	!!---------------------------------------------------------------------
157	!! * ROUTINE sbc_blk_init *
158	!!
159	!! ** Purpose : choose and initialize a bulk formulae formulation
160	!!
161	!! ** Method :
162	!!
163	!!----------------------------------------------------------------------
164	INTEGER :: ifpr, jfld ! dummy loop indice and argument
165	INTEGER :: ios, ierror, ioptio ! Local integer
166	!!
167	CHARACTER(len=100) :: cn_dir ! Root directory for location of atmospheric forcing files
168	TYPE(FLD_N), DIMENSION(jpfld) :: slf_i ! array of namelist informations on the fields to read
169	TYPE(FLD_N) :: sn_wndi, sn_wndj, sn_humi, sn_qsr ! informations about the fields to be read
170	TYPE(FLD_N) :: sn_qlw , sn_tair, sn_prec, sn_snow ! " "
171	TYPE(FLD_N) :: sn_slp , sn_tdif ! " "
172	NAMELIST/namsbc_blk/ sn_wndi, sn_wndj, sn_humi, sn_qsr, sn_qlw , & ! input fields
173	& sn_tair, sn_prec, sn_snow, sn_slp, sn_tdif, &
174	& ln_NCAR, ln_COARE_3p0, ln_COARE_3p5, ln_ECMWF, & ! bulk algorithm
175	& cn_dir , ln_taudif, rn_zqt, rn_zu, &
176	& rn_pfac, rn_efac, rn_vfac, ln_Cd_L12, ln_Cd_L15
177	!!---------------------------------------------------------------------
178	!
179	! ! allocate sbc_blk_core array
180	IF( sbc_blk_alloc() /= 0 ) CALL ctl_stop( 'STOP', 'sbc_blk : unable to allocate standard arrays' )
181	!
182	! !** read bulk namelist
183	REWIND( numnam_ref ) !* Namelist namsbc_blk in reference namelist : bulk parameters
184	READ ( numnam_ref, namsbc_blk, IOSTAT = ios, ERR = 901)
185	901 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namsbc_blk in reference namelist', lwp )
186	!
187	REWIND( numnam_cfg ) !* Namelist namsbc_blk in configuration namelist : bulk parameters
188	READ ( numnam_cfg, namsbc_blk, IOSTAT = ios, ERR = 902 )
189	902 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namsbc_blk in configuration namelist', lwp )
190	!
191	IF(lwm) WRITE( numond, namsbc_blk )
192	!
193	! !** initialization of the chosen bulk formulae (+ check)
194	! !* select the bulk chosen in the namelist and check the choice
195	ioptio = 0
196	IF( ln_NCAR ) THEN ; nblk = np_NCAR ; ioptio = ioptio + 1 ; ENDIF
197	IF( ln_COARE_3p0 ) THEN ; nblk = np_COARE_3p0 ; ioptio = ioptio + 1 ; ENDIF
198	IF( ln_COARE_3p5 ) THEN ; nblk = np_COARE_3p5 ; ioptio = ioptio + 1 ; ENDIF
199	IF( ln_ECMWF ) THEN ; nblk = np_ECMWF ; ioptio = ioptio + 1 ; ENDIF
200	!
201	IF( ioptio /= 1 ) CALL ctl_stop( 'sbc_blk_init: Choose one and only one bulk algorithm' )
202	!
203	IF( ln_dm2dc ) THEN !* check: diurnal cycle on Qsr
204	IF( sn_qsr%nfreqh /= 24 ) CALL ctl_stop( 'sbc_blk_init: ln_dm2dc=T only with daily short-wave input' )
205	IF( sn_qsr%ln_tint ) THEN
206	CALL ctl_warn( 'sbc_blk_init: ln_dm2dc=T daily qsr time interpolation done by sbcdcy module', &
207	& ' ==> We force time interpolation = .false. for qsr' )
208	sn_qsr%ln_tint = .false.
209	ENDIF
210	ENDIF
211	! !* set the bulk structure
212	! !- store namelist information in an array
213	slf_i(jp_wndi) = sn_wndi ; slf_i(jp_wndj) = sn_wndj
214	slf_i(jp_qsr ) = sn_qsr ; slf_i(jp_qlw ) = sn_qlw
215	slf_i(jp_tair) = sn_tair ; slf_i(jp_humi) = sn_humi
216	slf_i(jp_prec) = sn_prec ; slf_i(jp_snow) = sn_snow
217	slf_i(jp_slp) = sn_slp ; slf_i(jp_tdif) = sn_tdif
218	!
219	lhftau = ln_taudif !- add an extra field if HF stress is used
220	jfld = jpfld - COUNT( (/.NOT.lhftau/) )
221	!
222	! !- allocate the bulk structure
223	ALLOCATE( sf(jfld), STAT=ierror )
224	IF( ierror > 0 ) CALL ctl_stop( 'STOP', 'sbc_blk_init: unable to allocate sf structure' )
225	DO ifpr= 1, jfld
226	ALLOCATE( sf(ifpr)%fnow(jpi,jpj,1) )
227	IF( slf_i(ifpr)%ln_tint ) ALLOCATE( sf(ifpr)%fdta(jpi,jpj,1,2) )
228
229	IF( slf_i(ifpr)%nfreqh .GT. 0._wp .AND. MOD( 3600._wp * slf_i(ifpr)%nfreqh , REAL(nn_fsbc, wp) * rdt) .NE. 0._wp ) &
230	& CALL ctl_warn( 'sbcmod time step rdt * nn_fsbc is NOT a submultiple of atmospheric forcing frequency' )
231
232	END DO
233	! !- fill the bulk structure with namelist informations
234	CALL fld_fill( sf, slf_i, cn_dir, 'sbc_blk_init', 'surface boundary condition -- bulk formulae', 'namsbc_blk' )
235	!
236	IF ( ln_wave ) THEN
237	!Activated wave module but neither drag nor stokes drift activated
238	IF ( .NOT.(ln_cdgw .OR. ln_sdw .OR. ln_tauwoc .OR. ln_stcor ) ) THEN
239	CALL ctl_warn( 'Ask for wave coupling but ln_cdgw=F, ln_sdw=F, ln_tauwoc=F, ln_stcor=F')
240	!drag coefficient read from wave model definable only with mfs bulk formulae and core
241	ELSEIF (ln_cdgw .AND. .NOT. ln_NCAR ) THEN
242	CALL ctl_stop( 'drag coefficient read from wave model definable only with mfs bulk formulae and core')
243	ELSEIF (ln_stcor .AND. .NOT. ln_sdw) THEN
244	CALL ctl_stop( 'Stokes-Coriolis term calculated only if activated Stokes Drift ln_sdw=T')
245	ENDIF
246	ELSE
247	IF ( ln_cdgw .OR. ln_sdw .OR. ln_tauwoc .OR. ln_stcor ) &
248	& CALL ctl_stop( 'Not Activated Wave Module (ln_wave=F) but asked coupling ', &
249	& 'with drag coefficient (ln_cdgw =T) ' , &
250	& 'or Stokes Drift (ln_sdw=T) ' , &
251	& 'or ocean stress modification due to waves (ln_tauwoc=T) ', &
252	& 'or Stokes-Coriolis term (ln_stcori=T)' )
253	ENDIF
254	!
255	!
256	IF(lwp) THEN !** Control print
257	!
258	WRITE(numout,) ! namelist
259	WRITE(numout,*) ' Namelist namsbc_blk (other than data information):'
260	WRITE(numout,*) ' "NCAR" algorithm (Large and Yeager 2008) ln_NCAR = ', ln_NCAR
261	WRITE(numout,*) ' "COARE 3.0" algorithm (Fairall et al. 2003) ln_COARE_3p0 = ', ln_COARE_3p0
262	WRITE(numout,*) ' "COARE 3.5" algorithm (Edson et al. 2013) ln_COARE_3p5 = ', ln_COARE_3p0
263	WRITE(numout,*) ' "ECMWF" algorithm (IFS cycle 31) ln_ECMWF = ', ln_ECMWF
264	WRITE(numout,*) ' add High freq.contribution to the stress module ln_taudif = ', ln_taudif
265	WRITE(numout,*) ' Air temperature and humidity reference height (m) rn_zqt = ', rn_zqt
266	WRITE(numout,*) ' Wind vector reference height (m) rn_zu = ', rn_zu
267	WRITE(numout,*) ' factor applied on precipitation (total & snow) rn_pfac = ', rn_pfac
268	WRITE(numout,*) ' factor applied on evaporation rn_efac = ', rn_efac
269	WRITE(numout,*) ' factor applied on ocean/ice velocity rn_vfac = ', rn_vfac
270	WRITE(numout,*) ' (form absolute (=0) to relative winds(=1))'
271	WRITE(numout,*) ' use ice-atm drag from Lupkes2012 ln_Cd_L12 = ', ln_Cd_L12
272	WRITE(numout,*) ' use ice-atm drag from Lupkes2015 ln_Cd_L15 = ', ln_Cd_L15
273	!
274	WRITE(numout,*)
275	SELECT CASE( nblk ) !* Print the choice of bulk algorithm
276	CASE( np_NCAR ) ; WRITE(numout,*) ' ===>> "NCAR" algorithm (Large and Yeager 2008)'
277	CASE( np_COARE_3p0 ) ; WRITE(numout,*) ' ===>> "COARE 3.0" algorithm (Fairall et al. 2003)'
278	CASE( np_COARE_3p5 ) ; WRITE(numout,*) ' ===>> "COARE 3.5" algorithm (Edson et al. 2013)'
279	CASE( np_ECMWF ) ; WRITE(numout,*) ' ===>> "ECMWF" algorithm (IFS cycle 31)'
280	END SELECT
281	!
282	ENDIF
283	!
284	END SUBROUTINE sbc_blk_init
285
286
287	SUBROUTINE sbc_blk( kt )
288	!!---------------------------------------------------------------------
289	!! * ROUTINE sbc_blk *
290	!!
291	!! ** Purpose : provide at each time step the surface ocean fluxes
292	!! (momentum, heat, freshwater and runoff)
293	!!
294	!! ** Method : (1) READ each fluxes in NetCDF files:
295	!! the 10m wind velocity (i-component) (m/s) at T-point
296	!! the 10m wind velocity (j-component) (m/s) at T-point
297	!! the 10m or 2m specific humidity ( % )
298	!! the solar heat (W/m2)
299	!! the Long wave (W/m2)
300	!! the 10m or 2m air temperature (Kelvin)
301	!! the total precipitation (rain+snow) (Kg/m2/s)
302	!! the snow (solid prcipitation) (kg/m2/s)
303	!! the tau diff associated to HF tau (N/m2) at T-point (ln_taudif=T)
304	!! (2) CALL blk_oce
305	!!
306	!! C A U T I O N : never mask the surface stress fields
307	!! the stress is assumed to be in the (i,j) mesh referential
308	!!
309	!! ** Action : defined at each time-step at the air-sea interface
310	!! - utau, vtau i- and j-component of the wind stress
311	!! - taum wind stress module at T-point
312	!! - wndm wind speed module at T-point over free ocean or leads in presence of sea-ice
313	!! - qns, qsr non-solar and solar heat fluxes
314	!! - emp upward mass flux (evapo. - precip.)
315	!! - sfx salt flux due to freezing/melting (non-zero only if ice is present)
316	!! (set in limsbc(_2).F90)
317	!!
318	!! ** References : Large & Yeager, 2004 / Large & Yeager, 2008
319	!! Brodeau et al. Ocean Modelling 2010
320	!!----------------------------------------------------------------------
321	INTEGER, INTENT(in) :: kt ! ocean time step
322	!!---------------------------------------------------------------------
323	!
324	CALL fld_read( kt, nn_fsbc, sf ) ! input fields provided at the current time-step
325	!
326	! ! compute the surface ocean fluxes using bulk formulea
327	IF( MOD( kt - 1, nn_fsbc ) == 0 ) CALL blk_oce( kt, sf, sst_m, ssu_m, ssv_m )
328
329	#if defined key_cice
330	IF( MOD( kt - 1, nn_fsbc ) == 0 ) THEN
331	qlw_ice(:,:,1) = sf(jp_qlw )%fnow(:,:,1)
332	IF( ln_dm2dc ) THEN ; qsr_ice(:,:,1) = sbc_dcy( sf(jp_qsr)%fnow(:,:,1) )
333	ELSE ; qsr_ice(:,:,1) = sf(jp_qsr)%fnow(:,:,1)
334	ENDIF
335	tatm_ice(:,:) = sf(jp_tair)%fnow(:,:,1)
336	qatm_ice(:,:) = sf(jp_humi)%fnow(:,:,1)
337	tprecip(:,:) = sf(jp_prec)%fnow(:,:,1) * rn_pfac
338	sprecip(:,:) = sf(jp_snow)%fnow(:,:,1) * rn_pfac
339	wndi_ice(:,:) = sf(jp_wndi)%fnow(:,:,1)
340	wndj_ice(:,:) = sf(jp_wndj)%fnow(:,:,1)
341	ENDIF
342	#endif
343	!
344	END SUBROUTINE sbc_blk
345
346
347	SUBROUTINE blk_oce( kt, sf, pst, pu, pv )
348	!!---------------------------------------------------------------------
349	!! * ROUTINE blk_oce *
350	!!
351	!! ** Purpose : provide the momentum, heat and freshwater fluxes at
352	!! the ocean surface at each time step
353	!!
354	!! ** Method : bulk formulea for the ocean using atmospheric
355	!! fields read in sbc_read
356	!!
357	!! ** Outputs : - utau : i-component of the stress at U-point (N/m2)
358	!! - vtau : j-component of the stress at V-point (N/m2)
359	!! - taum : Wind stress module at T-point (N/m2)
360	!! - wndm : Wind speed module at T-point (m/s)
361	!! - qsr : Solar heat flux over the ocean (W/m2)
362	!! - qns : Non Solar heat flux over the ocean (W/m2)
363	!! - emp : evaporation minus precipitation (kg/m2/s)
364	!!
365	!! ** Nota : sf has to be a dummy argument for AGRIF on NEC
366	!!---------------------------------------------------------------------
367	INTEGER , INTENT(in ) :: kt ! time step index
368	TYPE(fld), INTENT(inout), DIMENSION(:) :: sf ! input data
369	REAL(wp) , INTENT(in) , DIMENSION(:,:) :: pst ! surface temperature [Celcius]
370	REAL(wp) , INTENT(in) , DIMENSION(:,:) :: pu ! surface current at U-point (i-component) [m/s]
371	REAL(wp) , INTENT(in) , DIMENSION(:,:) :: pv ! surface current at V-point (j-component) [m/s]
372	!
373	INTEGER :: ji, jj ! dummy loop indices
374	REAL(wp) :: zztmp ! local variable
375	REAL(wp), DIMENSION(jpi,jpj) :: zwnd_i, zwnd_j ! wind speed components at T-point
376	REAL(wp), DIMENSION(jpi,jpj) :: zsq ! specific humidity at pst
377	REAL(wp), DIMENSION(jpi,jpj) :: zqlw, zqsb ! long wave and sensible heat fluxes
378	REAL(wp), DIMENSION(jpi,jpj) :: zqla, zevap ! latent heat fluxes and evaporation
379	REAL(wp), DIMENSION(jpi,jpj) :: zst ! surface temperature in Kelvin
380	REAL(wp), DIMENSION(jpi,jpj) :: zU_zu ! bulk wind speed at height zu [m/s]
381	REAL(wp), DIMENSION(jpi,jpj) :: ztpot ! potential temperature of air at z=rn_zqt [K]
382	REAL(wp), DIMENSION(jpi,jpj) :: zrhoa ! density of air [kg/m^3]
383	!!---------------------------------------------------------------------
384	!
385	IF( ln_timing ) CALL timing_start('blk_oce')
386	!
387	! local scalars ( place there for vector optimisation purposes)
388	zst(:,:) = pst(:,:) + rt0 ! convert SST from Celcius to Kelvin (and set minimum value far above 0 K)
389
390	! ----------------------------------------------------------------------------- !
391	! 0 Wind components and module at T-point relative to the moving ocean !
392	! ----------------------------------------------------------------------------- !
393
394	! ... components ( U10m - U_oce ) at T-point (unmasked)
395	!!gm move zwnd_i (_j) set to zero inside the key_cyclone ???
396	zwnd_i(:,:) = 0._wp
397	zwnd_j(:,:) = 0._wp
398	#if defined key_cyclone
399	CALL wnd_cyc( kt, zwnd_i, zwnd_j ) ! add analytical tropical cyclone (Vincent et al. JGR 2012)
400	DO jj = 2, jpjm1
401	DO ji = fs_2, fs_jpim1 ! vect. opt.
402	sf(jp_wndi)%fnow(ji,jj,1) = sf(jp_wndi)%fnow(ji,jj,1) + zwnd_i(ji,jj)
403	sf(jp_wndj)%fnow(ji,jj,1) = sf(jp_wndj)%fnow(ji,jj,1) + zwnd_j(ji,jj)
404	END DO
405	END DO
406	#endif
407	DO jj = 2, jpjm1
408	DO ji = fs_2, fs_jpim1 ! vect. opt.
409	zwnd_i(ji,jj) = ( sf(jp_wndi)%fnow(ji,jj,1) - rn_vfac * 0.5 * ( pu(ji-1,jj ) + pu(ji,jj) ) )
410	zwnd_j(ji,jj) = ( sf(jp_wndj)%fnow(ji,jj,1) - rn_vfac * 0.5 * ( pv(ji ,jj-1) + pv(ji,jj) ) )
411	END DO
412	END DO
413	CALL lbc_lnk_multi( zwnd_i, 'T', -1., zwnd_j, 'T', -1. )
414	! ... scalar wind ( = \| U10m - U_oce \| ) at T-point (masked)
415	wndm(:,:) = SQRT( zwnd_i(:,:) * zwnd_i(:,:) &
416	& + zwnd_j(:,:) * zwnd_j(:,:) ) * tmask(:,:,1)
417
418	! ----------------------------------------------------------------------------- !
419	! I Radiative FLUXES !
420	! ----------------------------------------------------------------------------- !
421
422	! ocean albedo assumed to be constant + modify now Qsr to include the diurnal cycle ! Short Wave
423	zztmp = 1. - albo
424	IF( ln_dm2dc ) THEN ; qsr(:,:) = zztmp * sbc_dcy( sf(jp_qsr)%fnow(:,:,1) ) * tmask(:,:,1)
425	ELSE ; qsr(:,:) = zztmp * sf(jp_qsr)%fnow(:,:,1) * tmask(:,:,1)
426	ENDIF
427
428	zqlw(:,:) = ( sf(jp_qlw)%fnow(:,:,1) - Stef * zst(:,:)zst(:,:)zst(:,:)zst(:,:) ) tmask(:,:,1) ! Long Wave
429
430	! ----------------------------------------------------------------------------- !
431	! II Turbulent FLUXES !
432	! ----------------------------------------------------------------------------- !
433
434	! ... specific humidity at SST and IST tmask(
435	zsq(:,:) = 0.98 * q_sat( zst(:,:), sf(jp_slp)%fnow(:,:,1) )
436	!!
437	!! Estimate of potential temperature at z=rn_zqt, based on adiabatic lapse-rate
438	!! (see Josey, Gulev & Yu, 2013) / doi=10.1016/B978-0-12-391851-2.00005-2
439	!! (since reanalysis products provide T at z, not theta !)
440	ztpot = sf(jp_tair)%fnow(:,:,1) + gamma_moist( sf(jp_tair)%fnow(:,:,1), sf(jp_humi)%fnow(:,:,1) ) * rn_zqt
441
442	SELECT CASE( nblk ) !== transfer coefficients ==! Cd, Ch, Ce at T-point
443	!
444	CASE( np_NCAR ) ; CALL turb_ncar ( rn_zqt, rn_zu, zst, ztpot, zsq, sf(jp_humi)%fnow, wndm, & ! NCAR-COREv2
445	& Cd_atm, Ch_atm, Ce_atm, t_zu, q_zu, zU_zu, cdn_oce, chn_oce, cen_oce )
446	CASE( np_COARE_3p0 ) ; CALL turb_coare ( rn_zqt, rn_zu, zst, ztpot, zsq, sf(jp_humi)%fnow, wndm, & ! COARE v3.0
447	& Cd_atm, Ch_atm, Ce_atm, t_zu, q_zu, zU_zu, cdn_oce, chn_oce, cen_oce )
448	CASE( np_COARE_3p5 ) ; CALL turb_coare3p5( rn_zqt, rn_zu, zst, ztpot, zsq, sf(jp_humi)%fnow, wndm, & ! COARE v3.5
449	& Cd_atm, Ch_atm, Ce_atm, t_zu, q_zu, zU_zu, cdn_oce, chn_oce, cen_oce )
450	CASE( np_ECMWF ) ; CALL turb_ecmwf ( rn_zqt, rn_zu, zst, ztpot, zsq, sf(jp_humi)%fnow, wndm, & ! ECMWF
451	& Cd_atm, Ch_atm, Ce_atm, t_zu, q_zu, zU_zu, cdn_oce, chn_oce, cen_oce )
452	CASE DEFAULT
453	CALL ctl_stop( 'STOP', 'sbc_oce: non-existing bulk formula selected' )
454	END SELECT
455
456	! ! Compute true air density :
457	IF( ABS(rn_zu - rn_zqt) > 0.01 ) THEN ! At zu: (probably useless to remove zrhogravrn_zu from SLP...)
458	zrhoa(:,:) = rho_air( t_zu(:,:) , q_zu(:,:) , sf(jp_slp)%fnow(:,:,1) )
459	ELSE ! At zt:
460	zrhoa(:,:) = rho_air( sf(jp_tair)%fnow(:,:,1), sf(jp_humi)%fnow(:,:,1), sf(jp_slp)%fnow(:,:,1) )
461	END IF
462
463	!! CALL iom_put( "Cd_oce", Cd_atm) ! output value of pure ocean-atm. transfer coef.
464	!! CALL iom_put( "Ch_oce", Ch_atm) ! output value of pure ocean-atm. transfer coef.
465
466	DO jj = 1, jpj ! tau module, i and j component
467	DO ji = 1, jpi
468	zztmp = zrhoa(ji,jj) * zU_zu(ji,jj) * Cd_atm(ji,jj) ! using bulk wind speed
469	taum (ji,jj) = zztmp * wndm (ji,jj)
470	zwnd_i(ji,jj) = zztmp * zwnd_i(ji,jj)
471	zwnd_j(ji,jj) = zztmp * zwnd_j(ji,jj)
472	END DO
473	END DO
474
475	! ! add the HF tau contribution to the wind stress module
476	IF( lhftau ) taum(:,:) = taum(:,:) + sf(jp_tdif)%fnow(:,:,1)
477
478	CALL iom_put( "taum_oce", taum ) ! output wind stress module
479
480	! ... utau, vtau at U- and V_points, resp.
481	! Note the use of 0.5*(2-umask) in order to unmask the stress along coastlines
482	! Note the use of MAX(tmask(i,j),tmask(i+1,j) is to mask tau over ice shelves
483	DO jj = 1, jpjm1
484	DO ji = 1, fs_jpim1
485	utau(ji,jj) = 0.5 * ( 2. - umask(ji,jj,1) ) * ( zwnd_i(ji,jj) + zwnd_i(ji+1,jj ) ) &
486	& * MAX(tmask(ji,jj,1),tmask(ji+1,jj,1))
487	vtau(ji,jj) = 0.5 * ( 2. - vmask(ji,jj,1) ) * ( zwnd_j(ji,jj) + zwnd_j(ji ,jj+1) ) &
488	& * MAX(tmask(ji,jj,1),tmask(ji,jj+1,1))
489	END DO
490	END DO
491	CALL lbc_lnk_multi( utau, 'U', -1., vtau, 'V', -1. )
492
493	! Turbulent fluxes over ocean
494	! -----------------------------
495
496	! zqla used as temporary array, for rho*U (common term of bulk formulae):
497	zqla(:,:) = zrhoa(:,:) * zU_zu(:,:)
498
499	IF( ABS( rn_zu - rn_zqt) < 0.01_wp ) THEN
500	!! q_air and t_air are given at 10m (wind reference height)
501	zevap(:,:) = rn_efacMAX( 0._wp, zqla(:,:)Ce_atm(:,:)*(zsq(:,:) - sf(jp_humi)%fnow(:,:,1)) ) ! Evaporation, using bulk wind speed
502	zqsb (:,:) = cp_air(sf(jp_humi)%fnow(:,:,1))zqla(:,:)Ch_atm(:,:)*(zst(:,:) - ztpot(:,:) ) ! Sensible Heat, using bulk wind speed
503	ELSE
504	!! q_air and t_air are not given at 10m (wind reference height)
505	! Values of temp. and hum. adjusted to height of wind during bulk algorithm iteration must be used!!!
506	zevap(:,:) = rn_efacMAX( 0._wp, zqla(:,:)Ce_atm(:,:)*(zsq(:,:) - q_zu(:,:) ) ) ! Evaporation, using bulk wind speed
507	zqsb (:,:) = cp_air(sf(jp_humi)%fnow(:,:,1))zqla(:,:)Ch_atm(:,:)*(zst(:,:) - t_zu(:,:) ) ! Sensible Heat, using bulk wind speed
508	ENDIF
509
510	zqla(:,:) = L_vap(zst(:,:)) * zevap(:,:) ! Latent Heat flux
511
512
513	IF(ln_ctl) THEN
514	CALL prt_ctl( tab2d_1=zqla , clinfo1=' blk_oce: zqla : ', tab2d_2=Ce_atm , clinfo2=' Ce_oce : ' )
515	CALL prt_ctl( tab2d_1=zqsb , clinfo1=' blk_oce: zqsb : ', tab2d_2=Ch_atm , clinfo2=' Ch_oce : ' )
516	CALL prt_ctl( tab2d_1=zqlw , clinfo1=' blk_oce: zqlw : ', tab2d_2=qsr, clinfo2=' qsr : ' )
517	CALL prt_ctl( tab2d_1=zsq , clinfo1=' blk_oce: zsq : ', tab2d_2=zst, clinfo2=' zst : ' )
518	CALL prt_ctl( tab2d_1=utau , clinfo1=' blk_oce: utau : ', mask1=umask, &
519	& tab2d_2=vtau , clinfo2= ' vtau : ', mask2=vmask )
520	CALL prt_ctl( tab2d_1=wndm , clinfo1=' blk_oce: wndm : ')
521	CALL prt_ctl( tab2d_1=zst , clinfo1=' blk_oce: zst : ')
522	ENDIF
523
524	! ----------------------------------------------------------------------------- !
525	! III Total FLUXES !
526	! ----------------------------------------------------------------------------- !
527	!
528	emp (:,:) = ( zevap(:,:) & ! mass flux (evap. - precip.)
529	& - sf(jp_prec)%fnow(:,:,1) * rn_pfac ) * tmask(:,:,1)
530	!
531	qns(:,:) = zqlw(:,:) - zqsb(:,:) - zqla(:,:) & ! Downward Non Solar
532	& - sf(jp_snow)%fnow(:,:,1) * rn_pfac * lfus & ! remove latent melting heat for solid precip
533	& - zevap(:,:) * pst(:,:) * rcp & ! remove evap heat content at SST
534	& + ( sf(jp_prec)%fnow(:,:,1) - sf(jp_snow)%fnow(:,:,1) ) * rn_pfac & ! add liquid precip heat content at Tair
535	& * ( sf(jp_tair)%fnow(:,:,1) - rt0 ) * rcp &
536	& + sf(jp_snow)%fnow(:,:,1) * rn_pfac & ! add solid precip heat content at min(Tair,Tsnow)
537	& * ( MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow ) - rt0 ) * cpic * tmask(:,:,1)
538	!
539	#if defined key_lim3
540	qns_oce(:,:) = zqlw(:,:) - zqsb(:,:) - zqla(:,:) ! non solar without emp (only needed by LIM3)
541	qsr_oce(:,:) = qsr(:,:)
542	#endif
543	!
544	IF ( nn_ice == 0 ) THEN
545	CALL iom_put( "qlw_oce" , zqlw ) ! output downward longwave heat over the ocean
546	CALL iom_put( "qsb_oce" , - zqsb ) ! output downward sensible heat over the ocean
547	CALL iom_put( "qla_oce" , - zqla ) ! output downward latent heat over the ocean
548	CALL iom_put( "qemp_oce", qns-zqlw+zqsb+zqla ) ! output downward heat content of E-P over the ocean
549	CALL iom_put( "qns_oce" , qns ) ! output downward non solar heat over the ocean
550	CALL iom_put( "qsr_oce" , qsr ) ! output downward solar heat over the ocean
551	CALL iom_put( "qt_oce" , qns+qsr ) ! output total downward heat over the ocean
552	tprecip(:,:) = sf(jp_prec)%fnow(:,:,1) * rn_pfac ! output total precipitation [kg/m2/s]
553	sprecip(:,:) = sf(jp_snow)%fnow(:,:,1) * rn_pfac ! output solid precipitation [kg/m2/s]
554	CALL iom_put( 'snowpre', sprecip ) ! Snow
555	CALL iom_put( 'precip' , tprecip ) ! Total precipitation
556	ENDIF
557	!
558	IF(ln_ctl) THEN
559	CALL prt_ctl(tab2d_1=zqsb , clinfo1=' blk_oce: zqsb : ', tab2d_2=zqlw , clinfo2=' zqlw : ')
560	CALL prt_ctl(tab2d_1=zqla , clinfo1=' blk_oce: zqla : ', tab2d_2=qsr , clinfo2=' qsr : ')
561	CALL prt_ctl(tab2d_1=pst , clinfo1=' blk_oce: pst : ', tab2d_2=emp , clinfo2=' emp : ')
562	CALL prt_ctl(tab2d_1=utau , clinfo1=' blk_oce: utau : ', mask1=umask, &
563	& tab2d_2=vtau , clinfo2= ' vtau : ' , mask2=vmask )
564	ENDIF
565	!
566	IF( ln_timing ) CALL timing_stop('blk_oce')
567	!
568	END SUBROUTINE blk_oce
569
570
571
572	FUNCTION rho_air( ptak, pqa, pslp )
573	!!-------------------------------------------------------------------------------
574	!! * FUNCTION rho_air *
575	!!
576	!! ** Purpose : compute density of (moist) air using the eq. of state of the atmosphere
577	!!
578	!! ** Author: L. Brodeau, june 2016 / AeroBulk (https://sourceforge.net/p/aerobulk)
579	!!-------------------------------------------------------------------------------
580	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: ptak ! air temperature [K]
581	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pqa ! air specific humidity [kg/kg]
582	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pslp ! pressure in [Pa]
583	REAL(wp), DIMENSION(jpi,jpj) :: rho_air ! density of moist air [kg/m^3]
584	!!-------------------------------------------------------------------------------
585	!
586	rho_air = pslp / ( R_dryptak ( 1._wp + rctv0*pqa ) )
587	!
588	END FUNCTION rho_air
589
590
591	FUNCTION cp_air( pqa )
592	!!-------------------------------------------------------------------------------
593	!! * FUNCTION cp_air *
594	!!
595	!! ** Purpose : Compute specific heat (Cp) of moist air
596	!!
597	!! ** Author: L. Brodeau, june 2016 / AeroBulk (https://sourceforge.net/p/aerobulk)
598	!!-------------------------------------------------------------------------------
599	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pqa ! air specific humidity [kg/kg]
600	REAL(wp), DIMENSION(jpi,jpj) :: cp_air ! specific heat of moist air [J/K/kg]
601	!!-------------------------------------------------------------------------------
602	!
603	Cp_air = Cp_dry + Cp_vap * pqa
604	!
605	END FUNCTION cp_air
606
607
608	FUNCTION q_sat( ptak, pslp )
609	!!----------------------------------------------------------------------------------
610	!! * FUNCTION q_sat *
611	!!
612	!! ** Purpose : Specific humidity at saturation in [kg/kg]
613	!! Based on accurate estimate of "e_sat"
614	!! aka saturation water vapor (Goff, 1957)
615	!!
616	!! ** Author: L. Brodeau, june 2016 / AeroBulk (https://sourceforge.net/p/aerobulk)
617	!!----------------------------------------------------------------------------------
618	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: ptak ! air temperature [K]
619	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pslp ! sea level atmospheric pressure [Pa]
620	REAL(wp), DIMENSION(jpi,jpj) :: q_sat ! Specific humidity at saturation [kg/kg]
621	!
622	INTEGER :: ji, jj ! dummy loop indices
623	REAL(wp) :: ze_sat, ztmp ! local scalar
624	!!----------------------------------------------------------------------------------
625	!
626	DO jj = 1, jpj
627	DO ji = 1, jpi
628	!
629	ztmp = rt0 / ptak(ji,jj)
630	!
631	! Vapour pressure at saturation [hPa] : WMO, (Goff, 1957)
632	ze_sat = 10.*( 10.79574(1. - ztmp) - 5.028*LOG10(ptak(ji,jj)/rt0) &
633	& + 1.5047510.(-4)(1. - 10.*(-8.2969(ptak(ji,jj)/rt0 - 1.)) ) &
634	& + 0.4287310.(-3)(10.*(4.76955(1. - ztmp)) - 1.) + 0.78614 )
635	!
636	q_sat(ji,jj) = reps0 * ze_sat/( 0.01_wppslp(ji,jj) - (1._wp - reps0)ze_sat ) ! 0.01 because SLP is in [Pa]
637	!
638	END DO
639	END DO
640	!
641	END FUNCTION q_sat
642
643
644	FUNCTION gamma_moist( ptak, pqa )
645	!!----------------------------------------------------------------------------------
646	!! * FUNCTION gamma_moist *
647	!!
648	!! ** Purpose : Compute the moist adiabatic lapse-rate.
649	!! => http://glossary.ametsoc.org/wiki/Moist-adiabatic_lapse_rate
650	!! => http://www.geog.ucsb.edu/~joel/g266_s10/lecture_notes/chapt03/oh10_3_01/oh10_3_01.html
651	!!
652	!! ** Author: L. Brodeau, june 2016 / AeroBulk (https://sourceforge.net/p/aerobulk)
653	!!----------------------------------------------------------------------------------
654	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: ptak ! air temperature [K]
655	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: pqa ! specific humidity [kg/kg]
656	REAL(wp), DIMENSION(jpi,jpj) :: gamma_moist ! moist adiabatic lapse-rate
657	!
658	INTEGER :: ji, jj ! dummy loop indices
659	REAL(wp) :: zrv, ziRT ! local scalar
660	!!----------------------------------------------------------------------------------
661	!
662	DO jj = 1, jpj
663	DO ji = 1, jpi
664	zrv = pqa(ji,jj) / (1. - pqa(ji,jj))
665	ziRT = 1. / (R_dry*ptak(ji,jj)) ! 1/RT
666	gamma_moist(ji,jj) = grav * ( 1. + cevapzrvziRT ) / ( Cp_dry + cevapcevapzrvreps0ziRT/ptak(ji,jj) )
667	END DO
668	END DO
669	!
670	END FUNCTION gamma_moist
671
672
673	FUNCTION L_vap( psst )
674	!!---------------------------------------------------------------------------------
675	!! * FUNCTION L_vap *
676	!!
677	!! ** Purpose : Compute the latent heat of vaporization of water from temperature
678	!!
679	!! ** Author: L. Brodeau, june 2016 / AeroBulk (https://sourceforge.net/p/aerobulk)
680	!!----------------------------------------------------------------------------------
681	REAL(wp), DIMENSION(jpi,jpj) :: L_vap ! latent heat of vaporization [J/kg]
682	REAL(wp), DIMENSION(jpi,jpj), INTENT(in) :: psst ! water temperature [K]
683	!!----------------------------------------------------------------------------------
684	!
685	L_vap = ( 2.501 - 0.00237 * ( psst(:,:) - rt0) ) * 1.e6
686	!
687	END FUNCTION L_vap
688
689	#if defined key_lim3
690	!!----------------------------------------------------------------------
691	!! 'key_lim3' ESIM sea-ice model
692	!!----------------------------------------------------------------------
693	!! blk_ice_tau : provide the air-ice stress
694	!! blk_ice_flx : provide the heat and mass fluxes at air-ice interface
695	!! blk_ice_qcn : provide ice surface temperature and snow/ice conduction flux (emulating JULES coupler)
696	!! Cdn10_Lupkes2012 : Lupkes et al. (2012) air-ice drag
697	!! Cdn10_Lupkes2015 : Lupkes et al. (2015) air-ice drag
698	!!----------------------------------------------------------------------
699
700	SUBROUTINE blk_ice_tau
701	!!---------------------------------------------------------------------
702	!! * ROUTINE blk_ice_tau *
703	!!
704	!! ** Purpose : provide the surface boundary condition over sea-ice
705	!!
706	!! ** Method : compute momentum using bulk formulation
707	!! formulea, ice variables and read atmospheric fields.
708	!! NB: ice drag coefficient is assumed to be a constant
709	!!---------------------------------------------------------------------
710	INTEGER :: ji, jj ! dummy loop indices
711	REAL(wp) :: zwndi_f , zwndj_f, zwnorm_f ! relative wind module and components at F-point
712	REAL(wp) :: zwndi_t , zwndj_t ! relative wind components at T-point
713	REAL(wp), DIMENSION(jpi,jpj) :: zrhoa ! transfer coefficient for momentum (tau)
714	!!---------------------------------------------------------------------
715	!
716	IF( ln_timing ) CALL timing_start('blk_ice_tau')
717	!
718	! set transfer coefficients to default sea-ice values
719	Cd_atm(:,:) = Cd_ice
720	Ch_atm(:,:) = Cd_ice
721	Ce_atm(:,:) = Cd_ice
722
723	wndm_ice(:,:) = 0._wp !!gm brutal....
724
725	! ------------------------------------------------------------ !
726	! Wind module relative to the moving ice ( U10m - U_ice ) !
727	! ------------------------------------------------------------ !
728	SELECT CASE( cp_ice_msh )
729	CASE( 'I' ) ! B-grid ice dynamics : I-point (i.e. F-point with sea-ice indexation)
730	! and scalar wind at T-point ( = \| U10m - U_ice \| ) (masked)
731	DO jj = 2, jpjm1
732	DO ji = 2, jpim1 ! B grid : NO vector opt
733	! ... scalar wind at T-point (fld being at T-point)
734	zwndi_t = sf(jp_wndi)%fnow(ji,jj,1) - rn_vfac * 0.25 * ( u_ice(ji,jj+1) + u_ice(ji+1,jj+1) &
735	& + u_ice(ji,jj ) + u_ice(ji+1,jj ) )
736	zwndj_t = sf(jp_wndj)%fnow(ji,jj,1) - rn_vfac * 0.25 * ( v_ice(ji,jj+1) + v_ice(ji+1,jj+1) &
737	& + v_ice(ji,jj ) + v_ice(ji+1,jj ) )
738	wndm_ice(ji,jj) = SQRT( zwndi_t * zwndi_t + zwndj_t * zwndj_t ) * tmask(ji,jj,1)
739	END DO
740	END DO
741	CALL lbc_lnk( wndm_ice, 'T', 1. )
742	!
743	CASE( 'C' ) ! C-grid ice dynamics : U & V-points (same as ocean)
744	DO jj = 2, jpjm1
745	DO ji = fs_2, fs_jpim1 ! vect. opt.
746	zwndi_t = ( sf(jp_wndi)%fnow(ji,jj,1) - rn_vfac * 0.5 * ( u_ice(ji-1,jj ) + u_ice(ji,jj) ) )
747	zwndj_t = ( sf(jp_wndj)%fnow(ji,jj,1) - rn_vfac * 0.5 * ( v_ice(ji ,jj-1) + v_ice(ji,jj) ) )
748	wndm_ice(ji,jj) = SQRT( zwndi_t * zwndi_t + zwndj_t * zwndj_t ) * tmask(ji,jj,1)
749	END DO
750	END DO
751	CALL lbc_lnk( wndm_ice, 'T', 1. )
752	!
753	END SELECT
754
755	! Make ice-atm. drag dependent on ice concentration
756	IF ( ln_Cd_L12 ) THEN ! calculate new drag from Lupkes(2012) equations
757	CALL Cdn10_Lupkes2012( Cd_atm )
758	Ch_atm(:,:) = Cd_atm(:,:) ! momentum and heat transfer coef. are considered identical
759	ELSEIF( ln_Cd_L15 ) THEN ! calculate new drag from Lupkes(2015) equations
760	CALL Cdn10_Lupkes2015( Cd_atm, Ch_atm )
761	ENDIF
762
763	!! CALL iom_put( "Cd_ice", Cd_atm) ! output value of pure ice-atm. transfer coef.
764	!! CALL iom_put( "Ch_ice", Ch_atm) ! output value of pure ice-atm. transfer coef.
765
766	! local scalars ( place there for vector optimisation purposes)
767	! Computing density of air! Way denser that 1.2 over sea-ice !!!
768	zrhoa (:,:) = rho_air(sf(jp_tair)%fnow(:,:,1), sf(jp_humi)%fnow(:,:,1), sf(jp_slp)%fnow(:,:,1))
769
770	!!gm brutal....
771	utau_ice (:,:) = 0._wp
772	vtau_ice (:,:) = 0._wp
773	!!gm end
774
775	! ------------------------------------------------------------ !
776	! Wind stress relative to the moving ice ( U10m - U_ice ) !
777	! ------------------------------------------------------------ !
778	SELECT CASE( cp_ice_msh )
779	CASE( 'I' ) ! B-grid ice dynamics : I-point (i.e. F-point with sea-ice indexation)
780	DO jj = 2, jpjm1
781	DO ji = 2, jpim1 ! B grid : NO vector opt
782	! ... scalar wind at I-point (fld being at T-point)
783	zwndi_f = 0.25 * ( sf(jp_wndi)%fnow(ji-1,jj ,1) + sf(jp_wndi)%fnow(ji ,jj ,1) &
784	& + sf(jp_wndi)%fnow(ji-1,jj-1,1) + sf(jp_wndi)%fnow(ji ,jj-1,1) ) - rn_vfac * u_ice(ji,jj)
785	zwndj_f = 0.25 * ( sf(jp_wndj)%fnow(ji-1,jj ,1) + sf(jp_wndj)%fnow(ji ,jj ,1) &
786	& + sf(jp_wndj)%fnow(ji-1,jj-1,1) + sf(jp_wndj)%fnow(ji ,jj-1,1) ) - rn_vfac * v_ice(ji,jj)
787	! ... ice stress at I-point
788	zwnorm_f = zrhoa(ji,jj) * Cd_atm(ji,jj) * SQRT( zwndi_f * zwndi_f + zwndj_f * zwndj_f )
789	utau_ice(ji,jj) = zwnorm_f * zwndi_f
790	vtau_ice(ji,jj) = zwnorm_f * zwndj_f
791	END DO
792	END DO
793	CALL lbc_lnk_multi( utau_ice, 'I', -1., vtau_ice, 'I', -1. )
794	!
795	CASE( 'C' ) ! C-grid ice dynamics : U & V-points (same as ocean)
796	DO jj = 2, jpjm1
797	DO ji = fs_2, fs_jpim1 ! vect. opt.
798	utau_ice(ji,jj) = 0.5 * zrhoa(ji,jj) * Cd_atm(ji,jj) * ( wndm_ice(ji+1,jj ) + wndm_ice(ji,jj) ) &
799	& * ( 0.5 * (sf(jp_wndi)%fnow(ji+1,jj,1) + sf(jp_wndi)%fnow(ji,jj,1) ) - rn_vfac * u_ice(ji,jj) )
800	vtau_ice(ji,jj) = 0.5 * zrhoa(ji,jj) * Cd_atm(ji,jj) * ( wndm_ice(ji,jj+1 ) + wndm_ice(ji,jj) ) &
801	& * ( 0.5 * (sf(jp_wndj)%fnow(ji,jj+1,1) + sf(jp_wndj)%fnow(ji,jj,1) ) - rn_vfac * v_ice(ji,jj) )
802	END DO
803	END DO
804	CALL lbc_lnk_multi( utau_ice, 'U', -1., vtau_ice, 'V', -1. )
805	!
806	END SELECT
807	!
808	IF(ln_ctl) THEN
809	CALL prt_ctl(tab2d_1=utau_ice , clinfo1=' blk_ice: utau_ice : ', tab2d_2=vtau_ice , clinfo2=' vtau_ice : ')
810	CALL prt_ctl(tab2d_1=wndm_ice , clinfo1=' blk_ice: wndm_ice : ')
811	ENDIF
812	!
813	IF( ln_timing ) CALL timing_stop('blk_ice_tau')
814	!
815	END SUBROUTINE blk_ice_tau
816
817
818	SUBROUTINE blk_ice_flx( ptsu, phs, phi, palb )
819	!!---------------------------------------------------------------------
820	!! * ROUTINE blk_ice_flx *
821	!!
822	!! ** Purpose : provide the heat and mass fluxes at air-ice interface
823	!!
824	!! ** Method : compute heat and freshwater exchanged
825	!! between atmosphere and sea-ice using bulk formulation
826	!! formulea, ice variables and read atmmospheric fields.
827	!!
828	!! caution : the net upward water flux has with mm/day unit
829	!!---------------------------------------------------------------------
830	REAL(wp), DIMENSION(:,:,:), INTENT(in) :: ptsu ! sea ice surface temperature
831	REAL(wp), DIMENSION(:,:,:), INTENT(in) :: phs ! snow thickness
832	REAL(wp), DIMENSION(:,:,:), INTENT(in) :: phi ! ice thickness
833	REAL(wp), DIMENSION(:,:,:), INTENT(in) :: palb ! ice albedo (all skies)
834	!!
835	INTEGER :: ji, jj, jl ! dummy loop indices
836	REAL(wp) :: zst2, zst3 ! local variable
837	REAL(wp) :: zcoef_dqlw, zcoef_dqla ! - -
838	REAL(wp) :: zztmp, z1_lsub ! - -
839	REAL(wp) :: zfr1, zfr2 ! local variables
840	REAL(wp), DIMENSION(jpi,jpj,jpl) :: z_qlw ! long wave heat flux over ice
841	REAL(wp), DIMENSION(jpi,jpj,jpl) :: z_qsb ! sensible heat flux over ice
842	REAL(wp), DIMENSION(jpi,jpj,jpl) :: z_dqlw ! long wave heat sensitivity over ice
843	REAL(wp), DIMENSION(jpi,jpj,jpl) :: z_dqsb ! sensible heat sensitivity over ice
844	REAL(wp), DIMENSION(jpi,jpj) :: zevap, zsnw ! evaporation and snw distribution after wind blowing (LIM3)
845	REAL(wp), DIMENSION(jpi,jpj) :: zrhoa
846	!!---------------------------------------------------------------------
847	!
848	IF( ln_timing ) CALL timing_start('blk_ice_flx')
849	!
850	zcoef_dqlw = 4.0 * 0.95 * Stef ! local scalars
851	zcoef_dqla = -Ls * 11637800. * (-5897.8)
852	!
853	zrhoa(:,:) = rho_air( sf(jp_tair)%fnow(:,:,1), sf(jp_humi)%fnow(:,:,1), sf(jp_slp)%fnow(:,:,1) )
854	!
855	zztmp = 1. / ( 1. - albo )
856	! ! ========================== !
857	DO jl = 1, jpl ! Loop over ice categories !
858	! ! ========================== !
859	DO jj = 1 , jpj
860	DO ji = 1, jpi
861	! ----------------------------!
862	! I Radiative FLUXES !
863	! ----------------------------!
864	zst2 = ptsu(ji,jj,jl) * ptsu(ji,jj,jl)
865	zst3 = ptsu(ji,jj,jl) * zst2
866	! Short Wave (sw)
867	qsr_ice(ji,jj,jl) = zztmp * ( 1. - palb(ji,jj,jl) ) * qsr(ji,jj)
868	! Long Wave (lw)
869	z_qlw(ji,jj,jl) = 0.95 * ( sf(jp_qlw)%fnow(ji,jj,1) - Stef * ptsu(ji,jj,jl) * zst3 ) * tmask(ji,jj,1)
870	! lw sensitivity
871	z_dqlw(ji,jj,jl) = zcoef_dqlw * zst3
872
873	! ----------------------------!
874	! II Turbulent FLUXES !
875	! ----------------------------!
876
877	! ... turbulent heat fluxes with Ch_atm recalculated in blk_ice_tau
878	! Sensible Heat
879	z_qsb(ji,jj,jl) = zrhoa(ji,jj) * cpa * Ch_atm(ji,jj) * wndm_ice(ji,jj) * (ptsu(ji,jj,jl) - sf(jp_tair)%fnow(ji,jj,1))
880	! Latent Heat
881	qla_ice(ji,jj,jl) = rn_efac * MAX( 0.e0, zrhoa(ji,jj) * Ls * Ch_atm(ji,jj) * wndm_ice(ji,jj) * &
882	& ( 11637800. * EXP( -5897.8 / ptsu(ji,jj,jl) ) / zrhoa(ji,jj) - sf(jp_humi)%fnow(ji,jj,1) ) )
883	! Latent heat sensitivity for ice (Dqla/Dt)
884	IF( qla_ice(ji,jj,jl) > 0._wp ) THEN
885	dqla_ice(ji,jj,jl) = rn_efac * zcoef_dqla * Ch_atm(ji,jj) * wndm_ice(ji,jj) / zst2 * EXP(-5897.8 / ptsu(ji,jj,jl))
886	ELSE
887	dqla_ice(ji,jj,jl) = 0._wp
888	ENDIF
889
890	! Sensible heat sensitivity (Dqsb_ice/Dtn_ice)
891	z_dqsb(ji,jj,jl) = zrhoa(ji,jj) * cpa * Ch_atm(ji,jj) * wndm_ice(ji,jj)
892
893	! ----------------------------!
894	! III Total FLUXES !
895	! ----------------------------!
896	! Downward Non Solar flux
897	qns_ice (ji,jj,jl) = z_qlw (ji,jj,jl) - z_qsb (ji,jj,jl) - qla_ice (ji,jj,jl)
898	! Total non solar heat flux sensitivity for ice
899	dqns_ice(ji,jj,jl) = - ( z_dqlw(ji,jj,jl) + z_dqsb(ji,jj,jl) + dqla_ice(ji,jj,jl) )
900	END DO
901	!
902	END DO
903	!
904	END DO
905	!
906	tprecip(:,:) = sf(jp_prec)%fnow(:,:,1) * rn_pfac ! total precipitation [kg/m2/s]
907	sprecip(:,:) = sf(jp_snow)%fnow(:,:,1) * rn_pfac ! solid precipitation [kg/m2/s]
908	CALL iom_put( 'snowpre', sprecip ) ! Snow precipitation
909	CALL iom_put( 'precip' , tprecip ) ! Total precipitation
910
911	! --- evaporation --- !
912	z1_lsub = 1._wp / Lsub
913	evap_ice (:,:,:) = rn_efac * qla_ice (:,:,:) * z1_lsub ! sublimation
914	devap_ice(:,:,:) = rn_efac * dqla_ice(:,:,:) * z1_lsub ! d(sublimation)/dT
915	zevap (:,:) = rn_efac * ( emp(:,:) + tprecip(:,:) ) ! evaporation over ocean
916
917	! --- evaporation minus precipitation --- !
918	zsnw(:,:) = 0._wp
919	CALL ice_thd_snwblow( (1.-at_i_b(:,:)), zsnw ) ! snow distribution over ice after wind blowing
920	emp_oce(:,:) = ( 1._wp - at_i_b(:,:) ) * zevap(:,:) - ( tprecip(:,:) - sprecip(:,:) ) - sprecip(:,:) * (1._wp - zsnw )
921	emp_ice(:,:) = SUM( a_i_b(:,:,:) * evap_ice(:,:,:), dim=3 ) - sprecip(:,:) * zsnw
922	emp_tot(:,:) = emp_oce(:,:) + emp_ice(:,:)
923
924	! --- heat flux associated with emp --- !
925	qemp_oce(:,:) = - ( 1._wp - at_i_b(:,:) ) * zevap(:,:) * sst_m(:,:) * rcp & ! evap at sst
926	& + ( tprecip(:,:) - sprecip(:,:) ) * ( sf(jp_tair)%fnow(:,:,1) - rt0 ) * rcp & ! liquid precip at Tair
927	& + sprecip(:,:) * ( 1._wp - zsnw ) * & ! solid precip at min(Tair,Tsnow)
928	& ( ( MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow ) - rt0 ) * cpic * tmask(:,:,1) - lfus )
929	qemp_ice(:,:) = sprecip(:,:) * zsnw * & ! solid precip (only)
930	& ( ( MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow ) - rt0 ) * cpic * tmask(:,:,1) - lfus )
931
932	! --- total solar and non solar fluxes --- !
933	qns_tot(:,:) = ( 1._wp - at_i_b(:,:) ) * qns_oce(:,:) + SUM( a_i_b(:,:,:) * qns_ice(:,:,:), dim=3 ) &
934	& + qemp_ice(:,:) + qemp_oce(:,:)
935	qsr_tot(:,:) = ( 1._wp - at_i_b(:,:) ) * qsr_oce(:,:) + SUM( a_i_b(:,:,:) * qsr_ice(:,:,:), dim=3 )
936
937	! --- heat content of precip over ice in J/m3 (to be used in 1D-thermo) --- !
938	qprec_ice(:,:) = rhosn * ( ( MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow ) - rt0 ) * cpic * tmask(:,:,1) - lfus )
939
940	! --- heat content of evap over ice in W/m2 (to be used in 1D-thermo) ---
941	DO jl = 1, jpl
942	qevap_ice(:,:,jl) = 0._wp ! should be -evap_ice(:,:,jl)( ( Tice - rt0 ) cpic * tmask(:,:,1) )
943	! ! But we do not have Tice => consider it at 0degC => evap=0
944	END DO
945
946	! --- shortwave radiation transmitted below the surface (W/m2, see Grenfell Maykut 77) --- !
947	zfr1 = ( 0.18 * ( 1.0 - cldf_ice ) + 0.35 * cldf_ice ) ! transmission when hi>10cm
948	zfr2 = ( 0.82 * ( 1.0 - cldf_ice ) + 0.65 * cldf_ice ) ! zfr2 such that zfr1 + zfr2 to equal 1
949	!
950	WHERE ( phs(:,:,:) <= 0._wp .AND. phi(:,:,:) < 0.1_wp ) ! linear decrease from hi=0 to 10cm
951	qsr_ice_tr(:,:,:) = qsr_ice(:,:,:) * ( zfr1 + zfr2 * ( 1._wp - phi(:,:,:) * 10._wp ) )
952	ELSEWHERE( phs(:,:,:) <= 0._wp .AND. phi(:,:,:) >= 0.1_wp ) ! constant (zfr1) when hi>10cm
953	qsr_ice_tr(:,:,:) = qsr_ice(:,:,:) * zfr1
954	ELSEWHERE ! zero when hs>0
955	qsr_ice_tr(:,:,:) = 0._wp
956	END WHERE
957	!
958	IF(ln_ctl) THEN
959	CALL prt_ctl(tab3d_1=qla_ice , clinfo1=' blk_ice: qla_ice : ', tab3d_2=z_qsb , clinfo2=' z_qsb : ', kdim=jpl)
960	CALL prt_ctl(tab3d_1=z_qlw , clinfo1=' blk_ice: z_qlw : ', tab3d_2=dqla_ice, clinfo2=' dqla_ice : ', kdim=jpl)
961	CALL prt_ctl(tab3d_1=z_dqsb , clinfo1=' blk_ice: z_dqsb : ', tab3d_2=z_dqlw , clinfo2=' z_dqlw : ', kdim=jpl)
962	CALL prt_ctl(tab3d_1=dqns_ice, clinfo1=' blk_ice: dqns_ice : ', tab3d_2=qsr_ice , clinfo2=' qsr_ice : ', kdim=jpl)
963	CALL prt_ctl(tab3d_1=ptsu , clinfo1=' blk_ice: ptsu : ', tab3d_2=qns_ice , clinfo2=' qns_ice : ', kdim=jpl)
964	CALL prt_ctl(tab2d_1=tprecip , clinfo1=' blk_ice: tprecip : ', tab2d_2=sprecip , clinfo2=' sprecip : ')
965	ENDIF
966	!
967	IF( ln_timing ) CALL timing_stop('blk_ice_flx')
968	!
969	END SUBROUTINE blk_ice_flx
970
971
972	SUBROUTINE blk_ice_qcn( k_virtual_itd, ptsu, ptb, phs, phi )
973	!!---------------------------------------------------------------------
974	!! * ROUTINE blk_ice_qcn *
975	!!
976	!! ** Purpose : Compute surface temperature and snow/ice conduction flux
977	!! to force sea ice / snow thermodynamics
978	!! in the case JULES coupler is emulated
979	!!
980	!! ** Method : compute surface energy balance assuming neglecting heat storage
981	!! following the 0-layer Semtner (1976) approach
982	!!
983	!! ** Outputs : - ptsu : sea-ice / snow surface temperature (K)
984	!! - qcn_ice : surface inner conduction flux (W/m2)
985	!!
986	!!---------------------------------------------------------------------
987	INTEGER , INTENT(in ) :: k_virtual_itd ! single-category option
988	REAL(wp), DIMENSION(:,:,:), INTENT(inout) :: ptsu ! sea ice / snow surface temperature
989	REAL(wp), DIMENSION(:,:) , INTENT(in ) :: ptb ! sea ice base temperature
990	REAL(wp), DIMENSION(:,:,:), INTENT(in ) :: phs ! snow thickness
991	REAL(wp), DIMENSION(:,:,:), INTENT(in ) :: phi ! sea ice thickness
992	!
993	INTEGER , PARAMETER :: nit = 10 ! number of iterations
994	REAL(wp), PARAMETER :: zepsilon = 0.1_wp ! characteristic thickness for enhanced conduction
995	!
996	INTEGER :: ji, jj, jl ! dummy loop indices
997	INTEGER :: iter ! local integer
998	REAL(wp) :: zfac, zfac2, zfac3 ! local scalars
999	REAL(wp) :: zkeff_h, ztsu, ztsu0 !
1000	REAL(wp) :: zqc, zqnet !
1001	REAL(wp) :: zhe, zqa0 !
1002	REAL(wp), DIMENSION(jpi,jpj,jpl) :: zgfac ! enhanced conduction factor
1003	!!---------------------------------------------------------------------
1004
1005	IF( ln_timing ) CALL timing_start('blk_ice_qcn')
1006
1007	! -------------------------------------!
1008	! I Enhanced conduction factor !
1009	! -------------------------------------!
1010	! Emulates the enhancement of conduction by unresolved thin ice (k_virtual_itd = 1/2)
1011	! Fichefet and Morales Maqueda, JGR 1997
1012	!
1013	zgfac(:,:,:) = 1._wp
1014
1015	SELECT CASE ( k_virtual_itd )
1016	!
1017	CASE ( 1 , 2 )
1018	!
1019	zfac = 1._wp / ( rn_cnd_s + rcdic )
1020	zfac2 = EXP(1._wp) * 0.5_wp * zepsilon
1021	zfac3 = 2._wp / zepsilon
1022	!
1023	DO jl = 1, jpl
1024	DO jj = 1 , jpj
1025	DO ji = 1, jpi
1026	zhe = ( rn_cnd_s * phi(ji,jj,jl) + rcdic * phs(ji,jj,jl) ) * zfac ! Effective thickness
1027	IF( zhe >= zfac2 ) zgfac(ji,jj,jl) = MIN( 2._wp, 0.5_wp * ( 1._wp + LOG( zhe * zfac3 ) ) ) ! Enhanced conduction factor
1028	END DO
1029	END DO
1030	END DO
1031	!
1032	END SELECT
1033
1034	! -------------------------------------------------------------!
1035	! II Surface temperature and conduction flux !
1036	! -------------------------------------------------------------!
1037	!
1038	zfac = rcdic * rn_cnd_s
1039	!
1040	DO jl = 1, jpl
1041	DO jj = 1 , jpj
1042	DO ji = 1, jpi
1043	!
1044	zkeff_h = zfac * zgfac(ji,jj,jl) / & ! Effective conductivity of the snow-ice system divided by thickness
1045	& ( rcdic * phs(ji,jj,jl) + rn_cnd_s * MAX( 0.01, phi(ji,jj,jl) ) )
1046	ztsu = ptsu(ji,jj,jl) ! Store current iteration temperature
1047	ztsu0 = ptsu(ji,jj,jl) ! Store initial surface temperature
1048	zqa0 = qsr_ice(ji,jj,jl) - qsr_ice_tr(ji,jj,jl) + qns_ice(ji,jj,jl) ! Net initial atmospheric heat flux
1049	!
1050	DO iter = 1, nit ! --- Iterative loop
1051	zqc = zkeff_h * ( ztsu - ptb(ji,jj) ) ! Conduction heat flux through snow-ice system (>0 downwards)
1052	zqnet = zqa0 + dqns_ice(ji,jj,jl) * ( ztsu - ptsu(ji,jj,jl) ) - zqc ! Surface energy budget
1053	ztsu = ztsu - zqnet / ( dqns_ice(ji,jj,jl) - zkeff_h ) ! Temperature update
1054	END DO
1055	!
1056	ptsu (ji,jj,jl) = MIN( rt0, ztsu )
1057	qcn_ice(ji,jj,jl) = zkeff_h * ( ptsu(ji,jj,jl) - ptb(ji,jj) )
1058	qns_ice(ji,jj,jl) = qns_ice(ji,jj,jl) + dqns_ice(ji,jj,jl) * ( ptsu(ji,jj,jl) - ztsu0 )
1059	qml_ice(ji,jj,jl) = ( qsr_ice(ji,jj,jl) - qsr_ice_tr(ji,jj,jl) + qns_ice(ji,jj,jl) - qcn_ice(ji,jj,jl) ) &
1060	& * MAX( 0._wp , SIGN( 1._wp, ptsu(ji,jj,jl) - rt0 ) )
1061
1062	END DO
1063	END DO
1064	!
1065	END DO
1066	!
1067	IF( ln_timing ) CALL timing_stop('blk_ice_qcn')
1068	!
1069	END SUBROUTINE blk_ice_qcn
1070
1071
1072	SUBROUTINE Cdn10_Lupkes2012( Cd )
1073	!!----------------------------------------------------------------------
1074	!! * ROUTINE Cdn10_Lupkes2012 *
1075	!!
1076	!! ** Purpose : Recompute the neutral air-ice drag referenced at 10m
1077	!! to make it dependent on edges at leads, melt ponds and flows.
1078	!! After some approximations, this can be resumed to a dependency
1079	!! on ice concentration.
1080	!!
1081	!! ** Method : The parameterization is taken from Lupkes et al. (2012) eq.(50)
1082	!! with the highest level of approximation: level4, eq.(59)
1083	!! The generic drag over a cell partly covered by ice can be re-written as follows:
1084	!!
1085	!! Cd = Cdw * (1-A) + Cdi * A + Ce * (1-A)*(nu+1/(10beta)) * A**mu
1086	!!
1087	!! Ce = 2.23e-3 , as suggested by Lupkes (eq. 59)
1088	!! nu = mu = beta = 1 , as suggested by Lupkes (eq. 59)
1089	!! A is the concentration of ice minus melt ponds (if any)
1090	!!
1091	!! This new drag has a parabolic shape (as a function of A) starting at
1092	!! Cdw(say 1.5e-3) for A=0, reaching 1.97e-3 for A~0.5
1093	!! and going down to Cdi(say 1.4e-3) for A=1
1094	!!
1095	!! It is theoretically applicable to all ice conditions (not only MIZ)
1096	!! => see Lupkes et al (2013)
1097	!!
1098	!! ** References : Lupkes et al. JGR 2012 (theory)
1099	!! Lupkes et al. GRL 2013 (application to GCM)
1100	!!
1101	!!----------------------------------------------------------------------
1102	REAL(wp), DIMENSION(:,:), INTENT(inout) :: Cd
1103	REAL(wp), PARAMETER :: zCe = 2.23e-03_wp
1104	REAL(wp), PARAMETER :: znu = 1._wp
1105	REAL(wp), PARAMETER :: zmu = 1._wp
1106	REAL(wp), PARAMETER :: zbeta = 1._wp
1107	REAL(wp) :: zcoef
1108	!!----------------------------------------------------------------------
1109	zcoef = znu + 1._wp / ( 10._wp * zbeta )
1110
1111	! generic drag over a cell partly covered by ice
1112	!!Cd(:,:) = Cd_oce(:,:) * ( 1._wp - at_i_b(:,:) ) + & ! pure ocean drag
1113	!! & Cd_ice * at_i_b(:,:) + & ! pure ice drag
1114	!! & zCe * ( 1._wp - at_i_b(:,:) )*zcoef at_i_b(:,:)**zmu ! change due to sea-ice morphology
1115
1116	! ice-atm drag
1117	Cd(:,:) = Cd_ice + & ! pure ice drag
1118	& zCe * ( 1._wp - at_i_b(:,:) )*zcoef at_i_b(:,:)**(zmu-1._wp) ! change due to sea-ice morphology
1119
1120	END SUBROUTINE Cdn10_Lupkes2012
1121
1122
1123	SUBROUTINE Cdn10_Lupkes2015( Cd, Ch )
1124	!!----------------------------------------------------------------------
1125	!! * ROUTINE Cdn10_Lupkes2015 *
1126	!!
1127	!! ** pUrpose : Alternative turbulent transfert coefficients formulation
1128	!! between sea-ice and atmosphere with distinct momentum
1129	!! and heat coefficients depending on sea-ice concentration
1130	!! and atmospheric stability (no meltponds effect for now).
1131	!!
1132	!! ** Method : The parameterization is adapted from Lupkes et al. (2015)
1133	!! and ECHAM6 atmospheric model. Compared to Lupkes2012 scheme,
1134	!! it considers specific skin and form drags (Andreas et al. 2010)
1135	!! to compute neutral transfert coefficients for both heat and
1136	!! momemtum fluxes. Atmospheric stability effect on transfert
1137	!! coefficient is also taken into account following Louis (1979).
1138	!!
1139	!! ** References : Lupkes et al. JGR 2015 (theory)
1140	!! Lupkes et al. ECHAM6 documentation 2015 (implementation)
1141	!!
1142	!!----------------------------------------------------------------------
1143	!
1144	REAL(wp), DIMENSION(:,:), INTENT(inout) :: Cd
1145	REAL(wp), DIMENSION(:,:), INTENT(inout) :: Ch
1146	REAL(wp), DIMENSION(jpi,jpj) :: zst, zqo_sat, zqi_sat
1147	!
1148	! ECHAM6 constants
1149	REAL(wp), PARAMETER :: z0_skin_ice = 0.69e-3_wp ! Eq. 43 [m]
1150	REAL(wp), PARAMETER :: z0_form_ice = 0.57e-3_wp ! Eq. 42 [m]
1151	REAL(wp), PARAMETER :: z0_ice = 1.00e-3_wp ! Eq. 15 [m]
1152	REAL(wp), PARAMETER :: zce10 = 2.80e-3_wp ! Eq. 41
1153	REAL(wp), PARAMETER :: zbeta = 1.1_wp ! Eq. 41
1154	REAL(wp), PARAMETER :: zc = 5._wp ! Eq. 13
1155	REAL(wp), PARAMETER :: zc2 = zc * zc
1156	REAL(wp), PARAMETER :: zam = 2. * zc ! Eq. 14
1157	REAL(wp), PARAMETER :: zah = 3. * zc ! Eq. 30
1158	REAL(wp), PARAMETER :: z1_alpha = 1._wp / 0.2_wp ! Eq. 51
1159	REAL(wp), PARAMETER :: z1_alphaf = z1_alpha ! Eq. 56
1160	REAL(wp), PARAMETER :: zbetah = 1.e-3_wp ! Eq. 26
1161	REAL(wp), PARAMETER :: zgamma = 1.25_wp ! Eq. 26
1162	REAL(wp), PARAMETER :: z1_gamma = 1._wp / zgamma
1163	REAL(wp), PARAMETER :: r1_3 = 1._wp / 3._wp
1164	!
1165	INTEGER :: ji, jj ! dummy loop indices
1166	REAL(wp) :: zthetav_os, zthetav_is, zthetav_zu
1167	REAL(wp) :: zrib_o, zrib_i
1168	REAL(wp) :: zCdn_skin_ice, zCdn_form_ice, zCdn_ice
1169	REAL(wp) :: zChn_skin_ice, zChn_form_ice
1170	REAL(wp) :: z0w, z0i, zfmi, zfmw, zfhi, zfhw
1171	REAL(wp) :: zCdn_form_tmp
1172	!!----------------------------------------------------------------------
1173
1174	! Momentum Neutral Transfert Coefficients (should be a constant)
1175	zCdn_form_tmp = zce10 * ( LOG( 10._wp / z0_form_ice + 1._wp ) / LOG( rn_zu / z0_form_ice + 1._wp ) )**2 ! Eq. 40
1176	zCdn_skin_ice = ( vkarmn / LOG( rn_zu / z0_skin_ice + 1._wp ) )**2 ! Eq. 7
1177	zCdn_ice = zCdn_skin_ice ! Eq. 7 (cf Lupkes email for details)
1178	!zCdn_ice = 1.89e-3 ! old ECHAM5 value (cf Eq. 32)
1179
1180	! Heat Neutral Transfert Coefficients
1181	zChn_skin_ice = vkarmn*2 / ( LOG( rn_zu / z0_ice + 1._wp ) LOG( rn_zu * z1_alpha / z0_skin_ice + 1._wp ) ) ! Eq. 50 + Eq. 52 (cf Lupkes email for details)
1182
1183	! Atmospheric and Surface Variables
1184	zst(:,:) = sst_m(:,:) + rt0 ! convert SST from Celcius to Kelvin
1185	zqo_sat(:,:) = 0.98_wp * q_sat( zst(:,:) , sf(jp_slp)%fnow(:,:,1) ) ! saturation humidity over ocean [kg/kg]
1186	zqi_sat(:,:) = 0.98_wp * q_sat( tm_su(:,:), sf(jp_slp)%fnow(:,:,1) ) ! saturation humidity over ice [kg/kg]
1187	!
1188	DO jj = 2, jpjm1 ! reduced loop is necessary for reproducibility
1189	DO ji = fs_2, fs_jpim1
1190	! Virtual potential temperature [K]
1191	zthetav_os = zst(ji,jj) * ( 1._wp + rctv0 * zqo_sat(ji,jj) ) ! over ocean
1192	zthetav_is = tm_su(ji,jj) * ( 1._wp + rctv0 * zqi_sat(ji,jj) ) ! ocean ice
1193	zthetav_zu = t_zu (ji,jj) * ( 1._wp + rctv0 * q_zu(ji,jj) ) ! at zu
1194
1195	! Bulk Richardson Number (could use Ri_bulk function from aerobulk instead)
1196	zrib_o = grav / zthetav_os * ( zthetav_zu - zthetav_os ) * rn_zu / MAX( 0.5, wndm(ji,jj) )**2 ! over ocean
1197	zrib_i = grav / zthetav_is * ( zthetav_zu - zthetav_is ) * rn_zu / MAX( 0.5, wndm_ice(ji,jj) )**2 ! over ice
1198
1199	! Momentum and Heat Neutral Transfert Coefficients
1200	zCdn_form_ice = zCdn_form_tmp * at_i_b(ji,jj) * ( 1._wp - at_i_b(ji,jj) )**zbeta ! Eq. 40
1201	zChn_form_ice = zCdn_form_ice / ( 1._wp + ( LOG( z1_alphaf ) / vkarmn ) * SQRT( zCdn_form_ice ) ) ! Eq. 53
1202
1203	! Momentum and Heat Stability functions (possibility to use psi_m_ecmwf instead)
1204	z0w = rn_zu * EXP( -1._wp * vkarmn / SQRT( Cdn_oce(ji,jj) ) ) ! over water
1205	z0i = z0_skin_ice ! over ice (cf Lupkes email for details)
1206	IF( zrib_o <= 0._wp ) THEN
1207	zfmw = 1._wp - zam * zrib_o / ( 1._wp + 3._wp * zc2 * Cdn_oce(ji,jj) * SQRT( -zrib_o * ( rn_zu / z0w + 1._wp ) ) ) ! Eq. 10
1208	zfhw = ( 1._wp + ( zbetah * ( zthetav_os - zthetav_zu )*r1_3 / ( Chn_oce(ji,jj) MAX(0.01, wndm(ji,jj)) ) & ! Eq. 26
1209	& )zgamma )z1_gamma
1210	ELSE
1211	zfmw = 1._wp / ( 1._wp + zam * zrib_o / SQRT( 1._wp + zrib_o ) ) ! Eq. 12
1212	zfhw = 1._wp / ( 1._wp + zah * zrib_o / SQRT( 1._wp + zrib_o ) ) ! Eq. 28
1213	ENDIF
1214
1215	IF( zrib_i <= 0._wp ) THEN
1216	zfmi = 1._wp - zam * zrib_i / (1._wp + 3._wp * zc2 * zCdn_ice * SQRT( -zrib_i * ( rn_zu / z0i + 1._wp))) ! Eq. 9
1217	zfhi = 1._wp - zah * zrib_i / (1._wp + 3._wp * zc2 * zCdn_ice * SQRT( -zrib_i * ( rn_zu / z0i + 1._wp))) ! Eq. 25
1218	ELSE
1219	zfmi = 1._wp / ( 1._wp + zam * zrib_i / SQRT( 1._wp + zrib_i ) ) ! Eq. 11
1220	zfhi = 1._wp / ( 1._wp + zah * zrib_i / SQRT( 1._wp + zrib_i ) ) ! Eq. 27
1221	ENDIF
1222
1223	! Momentum Transfert Coefficients (Eq. 38)
1224	Cd(ji,jj) = zCdn_skin_ice * zfmi + &
1225	& zCdn_form_ice * ( zfmi * at_i_b(ji,jj) + zfmw * ( 1._wp - at_i_b(ji,jj) ) ) / MAX( 1.e-06, at_i_b(ji,jj) )
1226
1227	! Heat Transfert Coefficients (Eq. 49)
1228	Ch(ji,jj) = zChn_skin_ice * zfhi + &
1229	& zChn_form_ice * ( zfhi * at_i_b(ji,jj) + zfhw * ( 1._wp - at_i_b(ji,jj) ) ) / MAX( 1.e-06, at_i_b(ji,jj) )
1230	!
1231	END DO
1232	END DO
1233	CALL lbc_lnk_multi( Cd, 'T', 1., Ch, 'T', 1. )
1234	!
1235	END SUBROUTINE Cdn10_Lupkes2015
1236
1237	#endif
1238
1239	!!======================================================================
1240	END MODULE sbcblk

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