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diahth.F90 in NEMO/trunk/src/OCE/DIA – NEMO

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source: NEMO/trunk/src/OCE/DIA/diahth.F90 @ 12649

Last change on this file since 12649 was 12489, checked in by davestorkey, 4 years ago

Preparation for new timestepping scheme #2390.
Main changes:

Initial euler timestep now handled in stp and not in TRA/DYN routines.
Renaming of all timestep parameters. In summary, the namelist parameter is now rn_Dt and the current timestep is rDt (and rDt_ice, rDt_trc etc).
Renaming of a few miscellaneous parameters, eg. atfp -> rn_atfp (namelist parameter used everywhere) and rau0 -> rho0.

This version gives bit-comparable results to the previous version of the trunk.

Property svn:keywords set to Id

File size: 18.0 KB

Rev	Line
[3]	1	MODULE diahth
	2	!!======================================================================
	3	!! * MODULE diahth *
	4	!! Ocean diagnostics: thermocline and 20 degree depth
	5	!!======================================================================
[1485]	6	!! History : OPA ! 1994-09 (J.-P. Boulanger) Original code
	7	!! ! 1996-11 (E. Guilyardi) OPA8
	8	!! ! 1997-08 (G. Madec) optimization
	9	!! ! 1999-07 (E. Guilyardi) hd28 + heat content
[5836]	10	!! NEMO 1.0 ! 2002-06 (G. Madec) F90: Free form and module
	11	!! 3.2 ! 2009-07 (S. Masson) hc300 bugfix + cleaning + add new diag
[1485]	12	!!----------------------------------------------------------------------
[1577]	13	!! dia_hth : Compute varius diagnostics associated with the mixed layer
[3]	14	!!----------------------------------------------------------------------
	15	USE oce ! ocean dynamics and tracers
	16	USE dom_oce ! ocean space and time domain
	17	USE phycst ! physical constants
[6140]	18	!
[3]	19	USE in_out_manager ! I/O manager
[2715]	20	USE lib_mpp ! MPP library
[2528]	21	USE iom ! I/O library
[3294]	22	USE timing ! preformance summary
[3]	23
	24	IMPLICIT NONE
	25	PRIVATE
	26
[2715]	27	PUBLIC dia_hth ! routine called by step.F90
	28	PUBLIC dia_hth_alloc ! routine called by nemogcm.F90
[3]	29
[12276]	30	LOGICAL, SAVE :: l_hth !: thermocline-20d depths flag
[6140]	31
[1577]	32	! note: following variables should move to local variables once iom_put is always used
[2715]	33	REAL(wp), PUBLIC, ALLOCATABLE, SAVE, DIMENSION(:,:) :: hth !: depth of the max vertical temperature gradient [m]
	34	REAL(wp), PUBLIC, ALLOCATABLE, SAVE, DIMENSION(:,:) :: hd20 !: depth of 20 C isotherm [m]
[12276]	35	REAL(wp), PUBLIC, ALLOCATABLE, SAVE, DIMENSION(:,:) :: hd26 !: depth of 26 C isotherm [m]
[2715]	36	REAL(wp), PUBLIC, ALLOCATABLE, SAVE, DIMENSION(:,:) :: hd28 !: depth of 28 C isotherm [m]
	37	REAL(wp), PUBLIC, ALLOCATABLE, SAVE, DIMENSION(:,:) :: htc3 !: heat content of first 300 m [W]
[12276]	38	REAL(wp), PUBLIC, ALLOCATABLE, SAVE, DIMENSION(:,:) :: htc7 !: heat content of first 700 m [W]
	39	REAL(wp), PUBLIC, ALLOCATABLE, SAVE, DIMENSION(:,:) :: htc20 !: heat content of first 2000 m [W]
[3]	40
[12276]	41
[12377]	42	!! * Substitutions
	43	# include "do_loop_substitute.h90"
[3]	44	!!----------------------------------------------------------------------
[9598]	45	!! NEMO/OCE 4.0 , NEMO Consortium (2018)
[1152]	46	!! $Id$
[10068]	47	!! Software governed by the CeCILL license (see ./LICENSE)
[3]	48	!!----------------------------------------------------------------------
	49	CONTAINS
	50
[2715]	51	FUNCTION dia_hth_alloc()
	52	!!---------------------------------------------------------------------
	53	INTEGER :: dia_hth_alloc
	54	!!---------------------------------------------------------------------
	55	!
[12276]	56	ALLOCATE( hth(jpi,jpj), hd20(jpi,jpj), hd26(jpi,jpj), hd28(jpi,jpj), &
	57	& htc3(jpi,jpj), htc7(jpi,jpj), htc20(jpi,jpj), STAT=dia_hth_alloc )
[2715]	58	!
[10425]	59	CALL mpp_sum ( 'diahth', dia_hth_alloc )
	60	IF(dia_hth_alloc /= 0) CALL ctl_stop( 'STOP', 'dia_hth_alloc: failed to allocate arrays.' )
[2715]	61	!
	62	END FUNCTION dia_hth_alloc
	63
	64
[12377]	65	SUBROUTINE dia_hth( kt, Kmm )
[3]	66	!!---------------------------------------------------------------------
	67	!! * ROUTINE dia_hth *
	68	!!
[1577]	69	!! ** Purpose : Computes
	70	!! the mixing layer depth (turbocline): avt = 5.e-4
	71	!! the depth of strongest vertical temperature gradient
	72	!! the mixed layer depth with density criteria: rho = rho(10m or surf) + 0.03(or 0.01)
	73	!! the mixed layer depth with temperature criteria: abs( tn - tn(10m) ) = 0.2
	74	!! the top of the thermochine: tn = tn(10m) - ztem2
	75	!! the pycnocline depth with density criteria equivalent to a temperature variation
	76	!! rho = rho10m + (dr/dT)(T,S,10m)*(-0.2 degC)
	77	!! the barrier layer thickness
	78	!! the maximal verical inversion of temperature and its depth max( 0, max of tn - tn(10m) )
	79	!! the depth of the 20 degree isotherm (linear interpolation)
	80	!! the depth of the 28 degree isotherm (linear interpolation)
	81	!! the heat content of first 300 m
[3]	82	!!
	83	!! ** Method :
	84	!!-------------------------------------------------------------------
	85	INTEGER, INTENT( in ) :: kt ! ocean time-step index
[12377]	86	INTEGER, INTENT( in ) :: Kmm ! ocean time level index
[1485]	87	!!
[12276]	88	INTEGER :: ji, jj, jk ! dummy loop arguments
	89	REAL(wp) :: zrho3 = 0.03_wp ! density criterion for mixed layer depth
	90	REAL(wp) :: zrho1 = 0.01_wp ! density criterion for mixed layer depth
	91	REAL(wp) :: ztem2 = 0.2_wp ! temperature criterion for mixed layer depth
	92	REAL(wp) :: zztmp, zzdep ! temporary scalars inside do loop
	93	REAL(wp) :: zu, zv, zw, zut, zvt ! temporary workspace
	94	REAL(wp), DIMENSION(jpi,jpj) :: zabs2 ! MLD: abs( tn - tn(10m) ) = ztem2
	95	REAL(wp), DIMENSION(jpi,jpj) :: ztm2 ! Top of thermocline: tn = tn(10m) - ztem2
	96	REAL(wp), DIMENSION(jpi,jpj) :: zrho10_3 ! MLD: rho = rho10m + zrho3
	97	REAL(wp), DIMENSION(jpi,jpj) :: zpycn ! pycnocline: rho = rho10m + (dr/dT)(T,S,10m)*(-0.2 degC)
	98	REAL(wp), DIMENSION(jpi,jpj) :: ztinv ! max of temperature inversion
	99	REAL(wp), DIMENSION(jpi,jpj) :: zdepinv ! depth of temperature inversion
	100	REAL(wp), DIMENSION(jpi,jpj) :: zrho0_3 ! MLD rho = rho(surf) = 0.03
	101	REAL(wp), DIMENSION(jpi,jpj) :: zrho0_1 ! MLD rho = rho(surf) = 0.01
	102	REAL(wp), DIMENSION(jpi,jpj) :: zmaxdzT ! max of dT/dz
	103	REAL(wp), DIMENSION(jpi,jpj) :: zdelr ! delta rho equivalent to deltaT = 0.2
[3]	104	!!----------------------------------------------------------------------
[9124]	105	IF( ln_timing ) CALL timing_start('dia_hth')
[3]	106
	107	IF( kt == nit000 ) THEN
[12276]	108	l_hth = .FALSE.
	109	IF( iom_use( 'mlddzt' ) .OR. iom_use( 'mldr0_3' ) .OR. iom_use( 'mldr0_1' ) .OR. &
	110	& iom_use( 'mld_dt02' ) .OR. iom_use( 'topthdep' ) .OR. iom_use( 'mldr10_3' ) .OR. &
	111	& iom_use( '20d' ) .OR. iom_use( '26d' ) .OR. iom_use( '28d' ) .OR. &
	112	& iom_use( 'hc300' ) .OR. iom_use( 'hc700' ) .OR. iom_use( 'hc2000' ) .OR. &
	113	& iom_use( 'pycndep' ) .OR. iom_use( 'tinv' ) .OR. iom_use( 'depti' ) ) l_hth = .TRUE.
[2715]	114	! ! allocate dia_hth array
[12276]	115	IF( l_hth ) THEN
	116	IF( dia_hth_alloc() /= 0 ) CALL ctl_stop( 'STOP', 'dia_hth : unable to allocate standard arrays' )
	117	IF(lwp) WRITE(numout,*)
	118	IF(lwp) WRITE(numout,*) 'dia_hth : diagnostics of the thermocline depth'
	119	IF(lwp) WRITE(numout,*) '~~~~~~~ '
	120	IF(lwp) WRITE(numout,*)
	121	ENDIF
[3]	122	ENDIF
	123
[12276]	124	IF( l_hth ) THEN
	125	!
	126	IF( iom_use( 'mlddzt' ) .OR. iom_use( 'mldr0_3' ) .OR. iom_use( 'mldr0_1' ) ) THEN
	127	! initialization
	128	ztinv (:,:) = 0._wp
	129	zdepinv(:,:) = 0._wp
	130	zmaxdzT(:,:) = 0._wp
[12377]	131	DO_2D_11_11
	132	zztmp = gdepw(ji,jj,mbkt(ji,jj)+1,Kmm)
	133	hth (ji,jj) = zztmp
	134	zabs2 (ji,jj) = zztmp
	135	ztm2 (ji,jj) = zztmp
	136	zrho10_3(ji,jj) = zztmp
	137	zpycn (ji,jj) = zztmp
	138	END_2D
[12276]	139	IF( nla10 > 1 ) THEN
[12377]	140	DO_2D_11_11
	141	zztmp = gdepw(ji,jj,mbkt(ji,jj)+1,Kmm)
	142	zrho0_3(ji,jj) = zztmp
	143	zrho0_1(ji,jj) = zztmp
	144	END_2D
[12276]	145	ENDIF
[11993]	146
[12276]	147	! Preliminary computation
	148	! computation of zdelr = (dr/dT)(T,S,10m)*(-0.2 degC)
[12377]	149	DO_2D_11_11
	150	IF( tmask(ji,jj,nla10) == 1. ) THEN
	151	zu = 1779.50 + 11.250 * ts(ji,jj,nla10,jp_tem,Kmm) - 3.80 * ts(ji,jj,nla10,jp_sal,Kmm) &
	152	& - 0.0745 * ts(ji,jj,nla10,jp_tem,Kmm) * ts(ji,jj,nla10,jp_tem,Kmm) &
	153	& - 0.0100 * ts(ji,jj,nla10,jp_tem,Kmm) * ts(ji,jj,nla10,jp_sal,Kmm)
	154	zv = 5891.00 + 38.000 * ts(ji,jj,nla10,jp_tem,Kmm) + 3.00 * ts(ji,jj,nla10,jp_sal,Kmm) &
	155	& - 0.3750 * ts(ji,jj,nla10,jp_tem,Kmm) * ts(ji,jj,nla10,jp_tem,Kmm)
	156	zut = 11.25 - 0.149 * ts(ji,jj,nla10,jp_tem,Kmm) - 0.01 * ts(ji,jj,nla10,jp_sal,Kmm)
	157	zvt = 38.00 - 0.750 * ts(ji,jj,nla10,jp_tem,Kmm)
	158	zw = (zu + 0.698zv) (zu + 0.698*zv)
	159	zdelr(ji,jj) = ztem2 * (1000.(zutzv - zvt*zu)/zw)
	160	ELSE
	161	zdelr(ji,jj) = 0._wp
	162	ENDIF
	163	END_2D
[3]	164
[12276]	165	! ------------------------------------------------------------- !
	166	! thermocline depth: strongest vertical gradient of temperature !
	167	! turbocline depth (mixing layer depth): avt = zavt5 !
	168	! MLD: rho = rho(1) + zrho3 !
	169	! MLD: rho = rho(1) + zrho1 !
	170	! ------------------------------------------------------------- !
[12377]	171	DO_3DS_11_11( jpkm1, 2, -1 )
	172	!
	173	zzdep = gdepw(ji,jj,jk,Kmm)
	174	zztmp = ( ts(ji,jj,jk-1,jp_tem,Kmm) - ts(ji,jj,jk,jp_tem,Kmm) ) &
	175	& / zzdep * tmask(ji,jj,jk) ! vertical gradient of temperature (dT/dz)
	176	zzdep = zzdep * tmask(ji,jj,1)
[1577]	177
[12377]	178	IF( zztmp > zmaxdzT(ji,jj) ) THEN
	179	zmaxdzT(ji,jj) = zztmp
	180	hth (ji,jj) = zzdep ! max and depth of dT/dz
	181	ENDIF
[12276]	182
[12377]	183	IF( nla10 > 1 ) THEN
	184	zztmp = rhop(ji,jj,jk) - rhop(ji,jj,1) ! delta rho(1)
	185	IF( zztmp > zrho3 ) zrho0_3(ji,jj) = zzdep ! > 0.03
	186	IF( zztmp > zrho1 ) zrho0_1(ji,jj) = zzdep ! > 0.01
	187	ENDIF
	188	END_3D
	189
[12276]	190	CALL iom_put( 'mlddzt', hth ) ! depth of the thermocline
	191	IF( nla10 > 1 ) THEN
	192	CALL iom_put( 'mldr0_3', zrho0_3 ) ! MLD delta rho(surf) = 0.03
	193	CALL iom_put( 'mldr0_1', zrho0_1 ) ! MLD delta rho(surf) = 0.01
	194	ENDIF
	195	!
	196	ENDIF
	197	!
	198	IF( iom_use( 'mld_dt02' ) .OR. iom_use( 'topthdep' ) .OR. iom_use( 'mldr10_3' ) .OR. &
	199	& iom_use( 'pycndep' ) .OR. iom_use( 'tinv' ) .OR. iom_use( 'depti' ) ) THEN
	200	! ------------------------------------------------------------- !
	201	! MLD: abs( tn - tn(10m) ) = ztem2 !
	202	! Top of thermocline: tn = tn(10m) - ztem2 !
	203	! MLD: rho = rho10m + zrho3 !
	204	! pycnocline: rho = rho10m + (dr/dT)(T,S,10m)*(-0.2 degC) !
	205	! temperature inversion: max( 0, max of tn - tn(10m) ) !
	206	! depth of temperature inversion !
	207	! ------------------------------------------------------------- !
[12377]	208	DO_3DS_11_11( jpkm1, nlb10, -1 )
	209	!
	210	zzdep = gdepw(ji,jj,jk,Kmm) * tmask(ji,jj,1)
	211	!
	212	zztmp = ts(ji,jj,nla10,jp_tem,Kmm) - ts(ji,jj,jk,jp_tem,Kmm) ! - delta T(10m)
	213	IF( ABS(zztmp) > ztem2 ) zabs2 (ji,jj) = zzdep ! abs > 0.2
	214	IF( zztmp > ztem2 ) ztm2 (ji,jj) = zzdep ! > 0.2
	215	zztmp = -zztmp ! delta T(10m)
	216	IF( zztmp > ztinv(ji,jj) ) THEN ! temperature inversion
	217	ztinv(ji,jj) = zztmp
	218	zdepinv (ji,jj) = zzdep ! max value and depth
	219	ENDIF
[1577]	220
[12377]	221	zztmp = rhop(ji,jj,jk) - rhop(ji,jj,nla10) ! delta rho(10m)
	222	IF( zztmp > zrho3 ) zrho10_3(ji,jj) = zzdep ! > 0.03
	223	IF( zztmp > zdelr(ji,jj) ) zpycn (ji,jj) = zzdep ! > equi. delta T(10m) - 0.2
	224	!
	225	END_3D
[3]	226
[12276]	227	CALL iom_put( 'mld_dt02', zabs2 ) ! MLD abs(delta t) - 0.2
	228	CALL iom_put( 'topthdep', ztm2 ) ! T(10) - 0.2
	229	CALL iom_put( 'mldr10_3', zrho10_3 ) ! MLD delta rho(10m) = 0.03
	230	CALL iom_put( 'pycndep' , zpycn ) ! MLD delta rho equi. delta T(10m) = 0.2
	231	CALL iom_put( 'tinv' , ztinv ) ! max. temp. inv. (t10 ref)
	232	CALL iom_put( 'depti' , zdepinv ) ! depth of max. temp. inv. (t10 ref)
	233	!
	234	ENDIF
	235
	236	! ------------------------------- !
	237	! Depth of 20C/26C/28C isotherm !
	238	! ------------------------------- !
	239	IF( iom_use ('20d') ) THEN ! depth of the 20 isotherm
	240	ztem2 = 20.
[12377]	241	CALL dia_hth_dep( Kmm, ztem2, hd20 )
[12276]	242	CALL iom_put( '20d', hd20 )
	243	ENDIF
	244	!
	245	IF( iom_use ('26d') ) THEN ! depth of the 26 isotherm
	246	ztem2 = 26.
[12377]	247	CALL dia_hth_dep( Kmm, ztem2, hd26 )
[12276]	248	CALL iom_put( '26d', hd26 )
	249	ENDIF
	250	!
	251	IF( iom_use ('28d') ) THEN ! depth of the 28 isotherm
	252	ztem2 = 28.
[12377]	253	CALL dia_hth_dep( Kmm, ztem2, hd28 )
[12276]	254	CALL iom_put( '28d', hd28 )
	255	ENDIF
	256
	257	! ----------------------------- !
	258	! Heat content of first 300 m !
	259	! ----------------------------- !
	260	IF( iom_use ('hc300') ) THEN
	261	zzdep = 300.
[12377]	262	CALL dia_hth_htc( Kmm, zzdep, ts(:,:,:,jp_tem,Kmm), htc3 )
[12489]	263	CALL iom_put( 'hc300', rho0_rcp * htc3 ) ! vertically integrated heat content (J/m2)
[12276]	264	ENDIF
	265	!
	266	! ----------------------------- !
	267	! Heat content of first 700 m !
	268	! ----------------------------- !
	269	IF( iom_use ('hc700') ) THEN
	270	zzdep = 700.
[12377]	271	CALL dia_hth_htc( Kmm, zzdep, ts(:,:,:,jp_tem,Kmm), htc7 )
[12489]	272	CALL iom_put( 'hc700', rho0_rcp * htc7 ) ! vertically integrated heat content (J/m2)
[12276]	273
	274	ENDIF
	275	!
	276	! ----------------------------- !
	277	! Heat content of first 2000 m !
	278	! ----------------------------- !
	279	IF( iom_use ('hc2000') ) THEN
	280	zzdep = 2000.
[12377]	281	CALL dia_hth_htc( Kmm, zzdep, ts(:,:,:,jp_tem,Kmm), htc20 )
[12489]	282	CALL iom_put( 'hc2000', rho0_rcp * htc20 ) ! vertically integrated heat content (J/m2)
[12276]	283	ENDIF
	284	!
	285	ENDIF
[1577]	286
[12276]	287	!
	288	IF( ln_timing ) CALL timing_stop('dia_hth')
	289	!
	290	END SUBROUTINE dia_hth
[1577]	291
[12377]	292	SUBROUTINE dia_hth_dep( Kmm, ptem, pdept )
[12276]	293	!
[12377]	294	INTEGER , INTENT(in) :: Kmm ! ocean time level index
[12276]	295	REAL(wp), INTENT(in) :: ptem
	296	REAL(wp), DIMENSION(jpi,jpj), INTENT(out) :: pdept
	297	!
	298	INTEGER :: ji, jj, jk, iid
	299	REAL(wp) :: zztmp, zzdep
	300	INTEGER, DIMENSION(jpi,jpj) :: iktem
	301
	302	! --------------------------------------- !
	303	! search deepest level above ptem !
	304	! --------------------------------------- !
	305	iktem(:,:) = 1
[12377]	306	DO_3D_11_11( 1, jpkm1 )
	307	zztmp = ts(ji,jj,jk,jp_tem,Kmm)
	308	IF( zztmp >= ptem ) iktem(ji,jj) = jk
	309	END_3D
[1577]	310
[12276]	311	! ------------------------------- !
	312	! Depth of ptem isotherm !
	313	! ------------------------------- !
[12377]	314	DO_2D_11_11
	315	!
	316	zzdep = gdepw(ji,jj,mbkt(ji,jj)+1,Kmm) ! depth of the ocean bottom
	317	!
	318	iid = iktem(ji,jj)
	319	IF( iid /= 1 ) THEN
	320	zztmp = gdept(ji,jj,iid ,Kmm) & ! linear interpolation
	321	& + ( gdept(ji,jj,iid+1,Kmm) - gdept(ji,jj,iid,Kmm) ) &
	322	& * ( 20.*tmask(ji,jj,iid+1) - ts(ji,jj,iid,jp_tem,Kmm) ) &
	323	& / ( ts(ji,jj,iid+1,jp_tem,Kmm) - ts(ji,jj,iid,jp_tem,Kmm) + (1.-tmask(ji,jj,1)) )
	324	pdept(ji,jj) = MIN( zztmp , zzdep) * tmask(ji,jj,1) ! bound by the ocean depth
	325	ELSE
	326	pdept(ji,jj) = 0._wp
	327	ENDIF
	328	END_2D
[12276]	329	!
	330	END SUBROUTINE dia_hth_dep
[3]	331
	332
[12377]	333	SUBROUTINE dia_hth_htc( Kmm, pdep, pt, phtc )
[12276]	334	!
[12377]	335	INTEGER , INTENT(in) :: Kmm ! ocean time level index
[12276]	336	REAL(wp), INTENT(in) :: pdep ! depth over the heat content
[12377]	337	REAL(wp), DIMENSION(jpi,jpj,jpk), INTENT(in) :: pt
[12276]	338	REAL(wp), DIMENSION(jpi,jpj), INTENT(inout) :: phtc
	339	!
	340	INTEGER :: ji, jj, jk, ik
	341	REAL(wp), DIMENSION(jpi,jpj) :: zthick
	342	INTEGER , DIMENSION(jpi,jpj) :: ilevel
	343
	344
[1484]	345	! surface boundary condition
[12276]	346
	347	IF( .NOT. ln_linssh ) THEN ; zthick(:,:) = 0._wp ; phtc(:,:) = 0._wp
[12377]	348	ELSE ; zthick(:,:) = ssh(:,:,Kmm) ; phtc(:,:) = pt(:,:,1) * ssh(:,:,Kmm) * tmask(:,:,1)
[1484]	349	ENDIF
[12276]	350	!
	351	ilevel(:,:) = 1
[12377]	352	DO_3D_11_11( 2, jpkm1 )
	353	IF( ( gdept(ji,jj,jk,Kmm) < pdep ) .AND. ( tmask(ji,jj,jk) == 1 ) ) THEN
	354	ilevel(ji,jj) = jk
	355	zthick(ji,jj) = zthick(ji,jj) + e3t(ji,jj,jk,Kmm)
	356	phtc (ji,jj) = phtc (ji,jj) + e3t(ji,jj,jk,Kmm) * pt(ji,jj,jk)
	357	ENDIF
	358	END_3D
[12276]	359	!
[12377]	360	DO_2D_11_11
	361	ik = ilevel(ji,jj)
	362	zthick(ji,jj) = pdep - zthick(ji,jj) ! remaining thickness to reach depht pdep
	363	phtc(ji,jj) = phtc(ji,jj) + pt(ji,jj,ik+1) * MIN( e3t(ji,jj,ik+1,Kmm), zthick(ji,jj) ) &
	364	* tmask(ji,jj,ik+1)
	365	END_2D
[2528]	366	!
[3294]	367	!
[12276]	368	END SUBROUTINE dia_hth_htc
[3]	369
	370	!!======================================================================
	371	END MODULE diahth

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