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limmp.F90 in branches/2017/dev_r8183_ICEMODEL/NEMOGCM/NEMO/LIM_SRC_3 – NEMO

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source: branches/2017/dev_r8183_ICEMODEL/NEMOGCM/NEMO/LIM_SRC_3/limmp.F90 @ 8378

Last change on this file since 8378 was 8378, checked in by clem, 7 years ago
some cleaning
File size: 92.9 KB

Rev	Line
[7293]	1	MODULE limmp
	2	!!======================================================================
	3	!! * MODULE limmp *
	4	!! Melt ponds
	5	!!======================================================================
	6	!! history : ! Original code by Daniela Flocco and Adrian Turner
	7	!! 1.0 ! 2012 (O. Lecomte) Adaptation for scientific tests (NEMO3.1)
[8142]	8	!! 2.0 ! 2017 (M. Vancoppenolle, O. Lecomte, C. Rousset) Implementation in NEMO3.6
	9	!! ! NB: Only lim_mp_cstt and lim_mp_cesm work in this
	10	!! version
[7293]	11	!!----------------------------------------------------------------------
	12	#if defined key_lim3
	13	!!----------------------------------------------------------------------
	14	!! 'key_lim3' : LIM3 sea-ice model
	15	!!----------------------------------------------------------------------
	16	!! lim_mp_init : some initialization and namelist read
	17	!! lim_mp : main calling routine
[7325]	18	!! lim_mp_topo : main melt pond routine for the "topographic" formulation (FloccoFeltham)
	19	!! lim_mp_area : ??? compute melt pond fraction per category
	20	!! lim_mp_perm : computes permeability (should be a FUNCTION!)
[7293]	21	!! calc_hpond : computes melt pond depth
	22	!! permeability_phy : computes permeability
	23
	24	!!----------------------------------------------------------------------
[7325]	25	USE phycst ! physical constants
	26	USE dom_oce ! ocean space and time domain
[7293]	27	! USE sbc_ice ! Surface boundary condition: ice fields
	28	USE ice ! LIM-3 variables
[8378]	29	! USE limcons ! conservation tests
	30	! USE limctl ! control prints
	31	! USE limvar
	32	!
[7293]	33	USE lbclnk ! lateral boundary conditions - MPP exchanges
	34	USE lib_mpp ! MPP library
	35	USE in_out_manager ! I/O manager
	36	USE lib_fortran ! glob_sum
	37	USE timing ! Timing
	38
	39	!OLI_CODE USE ice_oce, ONLY: rdt_ice, tatm_ice
	40	!OLI_CODE USE phycst
	41	!OLI_CODE USE dom_ice
	42	!OLI_CODE USE dom_oce
	43	!OLI_CODE USE sbc_oce
	44	!OLI_CODE USE sbc_ice
	45	!OLI_CODE USE par_ice
	46	!OLI_CODE USE par_oce
	47	!OLI_CODE USE ice
	48	!OLI_CODE USE thd_ice
	49	!OLI_CODE USE in_out_manager
	50	!OLI_CODE USE lbclnk
	51	!OLI_CODE USE lib_mpp
	52	!OLI_CODE
	53	!OLI_CODE IMPLICIT NONE
	54	!OLI_CODE PRIVATE
	55	!OLI_CODE
	56	!OLI_CODE PUBLIC lim_mp_init
	57	!OLI_CODE PUBLIC lim_mp
	58
	59	IMPLICIT NONE
	60	PRIVATE
	61
[8321]	62	PUBLIC lim_mp_init ! routine called by icestp.F90
	63	PUBLIC lim_mp ! routine called by icestp.F90
[7293]	64
	65	!! * Substitutions
	66	# include "vectopt_loop_substitute.h90"
	67	!!----------------------------------------------------------------------
	68	!! NEMO/LIM3 4.0 , UCL - NEMO Consortium (2011)
	69	!! $Id: limdyn.F90 6994 2016-10-05 13:07:10Z clem $
	70	!! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt)
	71	!!----------------------------------------------------------------------
	72	CONTAINS
	73
	74	SUBROUTINE lim_mp_init
	75	!!-------------------------------------------------------------------
	76	!! * ROUTINE lim_mp_init *
	77	!!
	78	!! ** Purpose : Physical constants and parameters linked to melt ponds
	79	!! over sea ice
	80	!!
	81	!! ** Method : Read the namicemp namelist and check the melt pond
	82	!! parameter values called at the first timestep (nit000)
	83	!!
	84	!! ** input : Namelist namicemp
	85	!!-------------------------------------------------------------------
	86	INTEGER :: ios ! Local integer output status for namelist read
[8125]	87	NAMELIST/namicemp/ ln_pnd, ln_pnd_rad, ln_pnd_fw, nn_pnd_scheme, rn_apnd, rn_hpnd
[7293]	88	!!-------------------------------------------------------------------
	89
	90	REWIND( numnam_ice_ref ) ! Namelist namicemp in reference namelist : Melt Ponds
	91	READ ( numnam_ice_ref, namicemp, IOSTAT = ios, ERR = 901)
	92	901 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namicemp in reference namelist', lwp )
	93
	94	REWIND( numnam_ice_cfg ) ! Namelist namicemp in configuration namelist : Melt Ponds
	95	READ ( numnam_ice_cfg, namicemp, IOSTAT = ios, ERR = 902 )
	96	902 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namicemp in configuration namelist', lwp )
	97	IF(lwm) WRITE ( numoni, namicemp )
	98
	99	IF(lwp) THEN ! control print
	100	WRITE(numout,*)
	101	WRITE(numout,*) 'lim_mp_init : ice parameters for melt ponds'
	102	WRITE(numout,*) '~~~~~~~~~~~~'
[8125]	103	WRITE(numout,*) ' Active melt ponds ln_pnd = ', ln_pnd
	104	WRITE(numout,*) ' Active melt ponds radiative coupling ln_pnd_rad = ', ln_pnd_rad
	105	WRITE(numout,*) ' Active melt ponds freshwater coupling ln_pnd_fw = ', ln_pnd_fw
	106	WRITE(numout,*) ' Type of melt pond scheme =0 presc, =1 empirical = 2 topo nn_pnd_scheme = ', nn_pnd_scheme
	107	WRITE(numout,*) ' Prescribed pond fraction rn_apnd = ', rn_apnd
	108	WRITE(numout,*) ' Prescribed pond depth rn_hpnd = ', rn_hpnd
[7293]	109	ENDIF
[8085]	110
[8098]	111	IF ( .NOT. ln_pnd ) THEN
[8369]	112	IF(lwp) WRITE(numout,*)
	113	IF(lwp) WRITE(numout,*) ' Melt ponds are not activated '
	114	IF(lwp) WRITE(numout,*) ' ln_pnd_rad and ln_pnd_fw set to .FALSE. '
	115	IF(lwp) WRITE(numout,*) ' nn_pnd_scheme, rn_apnd, rn_hpnd set to zero '
[8125]	116	ln_pnd_rad = .FALSE.
	117	ln_pnd_fw = .FALSE.
[8085]	118	nn_pnd_scheme = 0
	119	rn_apnd = 0._wp
[8098]	120	rn_hpnd = 0._wp
[8125]	121
	122	IF(lwp) THEN ! control print
	123	WRITE(numout,*) ' Active melt ponds radiative coupling ln_pnd_rad = ', ln_pnd_rad
	124	WRITE(numout,*) ' Active melt ponds freshwater coupling ln_pnd_fw = ', ln_pnd_fw
	125	WRITE(numout,*) ' Type of melt pond scheme =0 presc, =1 empirical = 2 topo nn_pnd_scheme = ', nn_pnd_scheme
	126	WRITE(numout,*) ' Prescribed pond fraction rn_apnd = ', rn_apnd
	127	WRITE(numout,*) ' Prescribed pond depth rn_hpnd = ', rn_hpnd
	128	ENDIF
[8085]	129	ENDIF
[8098]	130
[8179]	131	IF ( ln_pnd .AND. ( nn_pnd_scheme == 0 ) .AND. ( ln_pnd_fw ) ) THEN
[8369]	132	IF(lwp) WRITE(numout,*) ' Prescribed melt ponds do not conserve fresh water mass, hence ln_pnd_fw must be set to false '
[8179]	133	ln_pnd_fw = .FALSE.
	134	IF(lwp) THEN ! control print
	135	WRITE(numout,*) ' Active melt ponds freshwater coupling ln_pnd_fw = ', ln_pnd_fw
	136	ENDIF
	137	ENDIF
	138
[8125]	139	IF ( ln_pnd .AND. ( nn_pnd_scheme == 2 ) .AND. ( jpl == 1 ) ) THEN
[8369]	140	IF(lwp) WRITE(numout,*) ' Topographic melt ponds are incompatible with jpl = 1 '
	141	IF(lwp) WRITE(numout,*) ' Run aborted '
[8125]	142	CALL ctl_stop( 'STOP', 'lim_mp_init: uncompatible options, reset namelist_ice_ref ' )
	143	ENDIF
	144
[7293]	145	!
	146	END SUBROUTINE lim_mp_init
[8098]	147
[7293]	148
[7325]	149	SUBROUTINE lim_mp( kt )
	150	!!-------------------------------------------------------------------
	151	!! * ROUTINE lim_mp *
	152	!!
	153	!! ** Purpose : change melt pond fraction
	154	!!
	155	!! ** Method : brutal force
	156	!!
	157	!! ** Action : -
	158	!! -
	159	!!------------------------------------------------------------------------------------
[7293]	160
[7325]	161	INTEGER, INTENT(in) :: kt ! number of iteration
	162	INTEGER :: ji, jj, jl ! dummy loop indices
[7293]	163
[7325]	164	!!-------------------------------------------------------------------
[7293]	165
[7325]	166	IF( nn_timing == 1 ) CALL timing_start('lim_mp')
[7293]	167
[8061]	168	SELECT CASE ( nn_pnd_scheme )
[7325]	169
[8098]	170	CASE (0)
	171
	172	CALL lim_mp_cstt ! staircase melt ponds
	173
[8085]	174	CASE (1)
[8060]	175
[8098]	176	CALL lim_mp_cesm ! empirical melt ponds
[8060]	177
[8085]	178	CASE (2)
[8061]	179
[8098]	180	CALL lim_mp_topo & ! topographic melt ponds
	181	& (at_i, a_i, &
	182	& vt_i, v_i, v_s, t_i, s_i, a_ip_frac, &
[8085]	183	& h_ip, t_su)
[8061]	184
	185	END SELECT
	186
[8142]	187	IF( nn_timing == 1 ) CALL timing_stop('lim_mp')
[7325]	188
	189	END SUBROUTINE lim_mp
	190
[8098]	191	SUBROUTINE lim_mp_cstt
	192	!!-------------------------------------------------------------------
	193	!! * ROUTINE lim_mp_cstt *
	194	!!
	195	!! ** Purpose : Compute melt pond evolution
	196	!!
	197	!! ** Method : Melt pond fraction and thickness are prescribed
	198	!! to non-zero values when t_su = 0C
	199	!!
	200	!! ** Tunable parameters : pond fraction (rn_apnd), pond depth (rn_hpnd)
	201	!!
	202	!! ** Note : Coupling with such melt ponds is only radiative
	203	!! Advection, ridging, rafting... are bypassed
	204	!!
	205	!! ** References : Bush, G.W., and Trump, D.J. (2017)
	206	!!
	207	!!-------------------------------------------------------------------
	208	INTEGER :: ji, jj, jl
	209	REAL(wp) :: z1_jpl ! 1/jpl
	210	!!-------------------------------------------------------------------
[8061]	211
[8098]	212	z1_jpl = 1. / FLOAT(jpl)
[8061]	213
[8098]	214	WHERE ( ( a_i > epsi10 ) .AND. ( t_su >= rt0-epsi06 ) )
[8106]	215	a_ip_frac = rn_apnd
[8098]	216	h_ip = rn_hpnd
[8106]	217	v_ip = a_ip_frac * a_i * h_ip
	218	a_ip = a_ip_frac * a_i
[8098]	219	ELSE WHERE
	220	a_ip = 0._wp
	221	h_ip = 0._wp
	222	v_ip = 0._wp
	223	a_ip_frac = 0._wp
	224	END WHERE
	225
	226	wfx_pnd(:,:) = 0._wp
	227
	228	END SUBROUTINE lim_mp_cstt
	229
[8060]	230	SUBROUTINE lim_mp_cesm
	231	!!-------------------------------------------------------------------
	232	!! * ROUTINE lim_mp_cesm *
	233	!!
	234	!! ** Purpose : Compute melt pond evolution
	235	!!
[8061]	236	!! ** Method : Empirical method. A fraction of meltwater is accumulated
	237	!! in pond volume. It is then released exponentially when
[8098]	238	!! surface is freezing.
[8060]	239	!!
[8142]	240	!! ** Tunable parameters : (no real expertise yet, ideas?)
[8060]	241	!!
	242	!! ** Note : Stolen from CICE for quick test of the melt pond
[8061]	243	!! radiation and freshwater interfaces
[8098]	244	!! Coupling can be radiative AND freshwater
	245	!! Advection, ridging, rafting are called
[8060]	246	!!
	247	!! ** References : Holland, M. M. et al (J Clim 2012)
	248	!!
	249	!!-------------------------------------------------------------------
	250
[8373]	251	INTEGER, DIMENSION(jpij) :: indxi ! compressed indices for cells with ice melting
	252	INTEGER, DIMENSION(jpij) :: indxj !
[8060]	253
[8373]	254	REAL(wp), DIMENSION(jpi,jpj) :: zwfx_mlw ! available meltwater for melt ponding
	255	REAL(wp), DIMENSION(jpi,jpj,jpl) :: zrfrac ! fraction of available meltwater retained for melt ponding
[8060]	256
[8373]	257	REAL(wp), PARAMETER :: zrmin = 0.15_wp ! minimum fraction of available meltwater retained for melt ponding
	258	REAL(wp), PARAMETER :: zrmax = 0.70_wp ! maximum '' '' '' '' ''
	259	REAL(wp), PARAMETER :: zrexp = 0.01_wp ! rate constant to refreeze melt ponds
	260	REAL(wp), PARAMETER :: zpnd_aspect = 0.8_wp ! pond aspect ratio
[8060]	261
[8373]	262	REAL(wp) :: zhi ! dummy ice thickness
	263	REAL(wp) :: zhs ! dummy snow depth
	264	REAL(wp) :: zTp ! reference temperature
	265	REAL(wp) :: zdTs ! dummy temperature difference
	266	REAL(wp) :: z1_rhofw ! inverse freshwater density
	267	REAL(wp) :: z1_zpnd_aspect ! inverse pond aspect ratio
	268	REAL(wp) :: zvpold ! dummy pond volume
[8060]	269
[8373]	270	INTEGER :: ji, jj, jl, ij ! loop indices
	271	INTEGER :: icells ! size of dummy array
[8060]	272	!!-------------------------------------------------------------------
[8142]	273	z1_rhofw = 1. / rhofw
	274	z1_zpnd_aspect = 1. / zpnd_aspect
	275	zTp = -2.
[8060]	276
[8142]	277	a_ip_frac(:,:,:) = 0._wp
	278	h_ip (:,:,:) = 0._wp
	279
	280	!------------------------------------------------------------------
	281	! Available melt water for melt ponding and corresponding fraction
	282	!------------------------------------------------------------------
	283
[8179]	284	zwfx_mlw(:,:) = MAX( wfx_sum(:,:) + wfx_snw_sum(:,:), 0._wp ) ! available meltwater for melt ponding
[8060]	285
[8142]	286	! NB: zwfx_mlw can be slightly negative for very small values (why?)
	287	! This can in some occasions give negative
	288	! v_ip in the first category, which then gives crazy pond
	289	! fractions and crashes the code as soon as the melt-pond
	290	! radiative coupling is activated
	291	! if we understand and remove why wfx_sum or wfx_snw could be
	292	! negative, then, we can remove the MAX
[8179]	293	! NB: I now changed to wfx_snw_sum, this may fix the problem.
	294	! We should check
[8142]	295
	296	zrfrac(:,:,:) = zrmin + ( zrmax - zrmin ) * a_i(:,:,:)
	297
	298	DO jl = 1, jpl
[8060]	299
[8142]	300	!------------------------------------------------------------------------------
	301	! Identify grid cells where ponds should be updated (can probably be improved)
	302	!------------------------------------------------------------------------------
	303
	304	indxi(:) = 0
	305	indxj(:) = 0
	306	icells = 0
	307
	308	DO jj = 1, jpj
	309	DO ji = 1, jpi
	310	IF ( a_i(ji,jj,jl) > epsi10 ) THEN
	311	icells = icells + 1
	312	indxi(icells) = ji
	313	indxj(icells) = jj
	314	ENDIF
	315	END DO ! ji
	316	END DO ! jj
	317
	318	DO ij = 1, icells
	319
	320	ji = indxi(ij)
	321	jj = indxj(ij)
	322
	323	zhi = v_i(ji,jj,jl) / a_i(ji,jj,jl)
	324	zhs = v_s(ji,jj,jl) / a_i(ji,jj,jl)
	325
	326	IF ( zhi < rn_himin) THEN !--- Remove ponds on thin ice if ice is too thin
	327
	328	a_ip(ji,jj,jl) = 0._wp !--- Dump ponds
	329	v_ip(ji,jj,jl) = 0._wp
	330	a_ip_frac(ji,jj,jl) = 0._wp
	331	h_ip(ji,jj,jl) = 0._wp
	332
	333	IF ( ln_pnd_fw ) & !--- Give freshwater to the ocean
	334	wfx_pnd(ji,jj) = wfx_pnd(ji,jj) + v_ip(ji,jj,jl)
	335
	336
	337	ELSE !--- Update pond characteristics
	338
	339	!--- Add retained melt water to melt ponds
	340	! v_ip should never be positive, otherwise code crashes
	341	! MV: as far as I saw, UM5 can create very small negative v_ip values
	342	! hence I added the max, which was not required with Prather (1 yr run)
	343	v_ip(ji,jj,jl) = MAX( v_ip(ji,jj,jl), 0._wp ) + zrfrac(ji,jj,jl) * z1_rhofw * zwfx_mlw(ji,jj) * a_i(ji,jj,jl) * rdt_ice
	344
	345	!--- Shrink pond due to refreezing
	346	zdTs = MAX ( zTp - t_su(ji,jj,jl) + rt0 , 0. )
	347
	348	zvpold = v_ip(ji,jj,jl)
	349
	350	v_ip(ji,jj,jl) = v_ip(ji,jj,jl) * EXP( zrexp * zdTs / zTp )
	351
	352	!--- Dump meltwater due to refreezing ( of course this is wrong
	353	!--- but this parameterization is too simple )
	354	IF ( ln_pnd_fw ) &
	355	wfx_pnd(ji,jj) = wfx_pnd(ji,jj) + rhofw * ( v_ip(ji,jj,jl) - zvpold ) * r1_rdtice
	356
	357	a_ip_frac(ji,jj,jl) = MIN( 1._wp , SQRT( v_ip(ji,jj,jl) * z1_zpnd_aspect / a_i(ji,jj,jl) ) )
[8179]	358	!NB: the SQRT has been a recurring source of crash when v_ip or a_i tuns to be even only slightly negative
[8142]	359
	360	h_ip(ji,jj,jl) = zpnd_aspect * a_ip_frac(ji,jj,jl)
	361
	362	a_ip(ji,jj,jl) = a_ip_frac(ji,jj,jl) * a_i(ji,jj,jl)
	363
	364	!-----------------------------------------------------------
	365	! Limit pond depth
	366	!-----------------------------------------------------------
	367	! The original version has pond depth limitation, which I did not
	368	! keep here. Maybe we need it later on
	369	!
	370
	371	ENDIF
	372
	373	END DO
	374
	375	END DO ! jpl
	376
	377	!--- Remove retained meltwater from surface fluxes
	378
	379	IF ( ln_pnd_fw ) THEN
	380
[8179]	381	wfx_snw_sum(:,:) = wfx_snw_sum(:,:) * ( 1. - zrmin - ( zrmax - zrmin ) * at_i(:,:) )
	382
	383	wfx_sum(:,:) = wfx_sum(:,:) * ( 1. - zrmin - ( zrmax - zrmin ) * at_i(:,:) )
	384
[8142]	385	ENDIF
[8060]	386
	387	END SUBROUTINE lim_mp_cesm
	388
[7325]	389	SUBROUTINE lim_mp_topo (aice, aicen, &
	390	vice, vicen, &
	391	vsnon, &
	392	ticen, salin, &
	393	a_ip_frac, h_ip, &
	394	Tsfc )
	395	!!-------------------------------------------------------------------
	396	!! * ROUTINE lim_mp_topo *
	397	!!
	398	!! ** Purpose : Compute melt pond evolution based on the ice
	399	!! topography as inferred from the ice thickness
	400	!! distribution.
	401	!!
	402	!! ** Method : This code is initially based on Flocco and Feltham
	403	!! (2007) and Flocco et al. (2010). More to come...
	404	!!
	405	!! ** Tunable parameters :
	406	!!
	407	!! ** Note :
	408	!!
	409	!! ** References
	410	!! Flocco, D. and D. L. Feltham, 2007. A continuum model of melt pond
	411	!! evolution on Arctic sea ice. J. Geophys. Res. 112, C08016, doi:
	412	!! 10.1029/2006JC003836.
	413	!! Flocco, D., D. L. Feltham and A. K. Turner, 2010. Incorporation of
	414	!! a physically based melt pond scheme into the sea ice component of a
	415	!! climate model. J. Geophys. Res. 115, C08012,
	416	!! doi: 10.1029/2009JC005568.
	417	!!
	418	!!-------------------------------------------------------------------
	419
	420	REAL (wp), DIMENSION (jpi,jpj), &
	421	INTENT(IN) :: &
	422	aice, & ! total ice area fraction
	423	vice ! total ice volume (m)
	424
	425	REAL (wp), DIMENSION (jpi,jpj,jpl), &
	426	INTENT(IN) :: &
	427	aicen, & ! ice area fraction, per category
	428	vsnon, & ! snow volume, per category (m)
	429	vicen ! ice volume, per category (m)
	430
	431	REAL (wp), DIMENSION (jpi,jpj,nlay_i,jpl), &
	432	INTENT(IN) :: &
	433	ticen, & ! ice enthalpy, per category
	434	salin
	435
	436	REAL (wp), DIMENSION (jpi,jpj,jpl), &
	437	INTENT(INOUT) :: &
	438	a_ip_frac , & ! pond area fraction of ice, per ice category
	439	h_ip ! pond depth, per ice category (m)
	440
	441	REAL (wp), DIMENSION (jpi,jpj,jpl), &
	442	INTENT(IN) :: &
	443	Tsfc ! snow/sea ice surface temperature
	444
	445	! local variables
	446	REAL (wp), DIMENSION (jpi,jpj,jpl) :: &
	447	zTsfcn, & ! ice/snow surface temperature (C)
	448	zvolpn, & ! pond volume per unit area, per category (m)
	449	zvuin ! water-equivalent volume of ice lid on melt pond ('upper ice', m)
	450
	451	REAL (wp), DIMENSION (jpi,jpj,jpl) :: &
	452	zapondn,& ! pond area fraction, per category
	453	zhpondn ! pond depth, per category (m)
	454
	455	REAL (wp), DIMENSION (jpi,jpj) :: &
	456	zvolp ! total volume of pond, per unit area of pond (m)
	457
	458	REAL (wp) :: &
	459	zhi, & ! ice thickness (m)
	460	zdHui, & ! change in thickness of ice lid (m)
	461	zomega, & ! conduction
	462	zdTice, & ! temperature difference across ice lid (C)
	463	zdvice, & ! change in ice volume (m)
	464	zTavg, & ! mean surface temperature across categories (C)
	465	zTp, & ! pond freezing temperature (C)
	466	zdvn ! change in melt pond volume for fresh water budget
	467	INTEGER, DIMENSION (jpi*jpj) :: &
	468	indxi, indxj ! compressed indices for cells with ice melting
	469
	470	INTEGER :: n,k,i,j,ij,icells,indxij ! loop indices
	471
	472	INTEGER, DIMENSION (jpl) :: &
	473	kcells ! cells where ice lid combines with vice
	474
	475	INTEGER, DIMENSION (jpi*jpj,jpl) :: &
	476	indxii, indxjj ! i,j indices for kcells loop
	477
	478	REAL (wp), parameter :: &
	479	zhicemin = 0.1_wp , & ! minimum ice thickness with ponds (m)
	480	zTd = 0.15_wp, & ! temperature difference for freeze-up (C)
	481	zr1_rlfus = 1._wp / 0.334e+6 / 917._wp , & ! (J/m^3)
	482	zmin_volp = 1.e-4_wp, & ! minimum pond volume (m)
	483	z0 = 0._wp, &
	484	zTimelt = 0._wp, &
	485	z01 = 0.01_wp, &
	486	z25 = 0.25_wp, &
	487	z5 = 0.5_wp
	488
	489	!---------------------------------------------------------------
	490	! Initialization
	491	!---------------------------------------------------------------
	492
	493	zhpondn(:,:,:) = 0._wp
	494	zapondn(:,:,:) = 0._wp
	495	indxii(:,:) = 0
	496	indxjj(:,:) = 0
	497	kcells(:) = 0
	498
[8179]	499	zvolp(:,:) = wfx_sum(:,:) + wfx_snw_sum(:,:) + vt_ip(:,:) ! Total available melt water, to be distributed as melt ponds
[7325]	500	zTsfcn(:,:,:) = zTsfcn(:,:,:) - rt0 ! Convert in Celsius
	501
	502	! The freezing temperature for meltponds is assumed slightly below 0C,
	503	! as if meltponds had a little salt in them. The salt budget is not
	504	! altered for meltponds, but if it were then an actual pond freezing
	505	! temperature could be computed.
	506
	507	! zTp = zTimelt - zTd ---> for lids
	508
	509	!-----------------------------------------------------------------
	510	! Identify grid cells with ponds
	511	!-----------------------------------------------------------------
	512
	513	icells = 0
	514	DO j = 1, jpj
	515	DO i = 1, jpi
	516	zhi = z0
	517	IF (aice(i,j) > epsi10 ) zhi = vice(i,j)/aice(i,j)
	518	IF ( aice(i,j) > z01 .and. zhi > zhicemin .and. &
	519	zvolp(i,j) > zmin_volp*aice(i,j)) THEN
	520	icells = icells + 1
	521	indxi(icells) = i
	522	indxj(icells) = j
	523	ELSE ! remove ponds on thin ice
	524	!fpond(i,j) = fpond(i,j) - zvolp(i,j)
	525	zvolpn(i,j,:) = z0
	526	zvuin (i,j,:) = z0
	527	zvolp (i,j) = z0
	528	END IF
	529	END DO ! i
	530	END DO ! j
	531
	532	DO ij = 1, icells
	533	i = indxi(ij)
	534	j = indxj(ij)
	535
	536	!--------------------------------------------------------------
	537	! calculate pond area and depth
	538	!--------------------------------------------------------------
	539	CALL lim_mp_area(aice(i,j),vice(i,j), &
	540	aicen(i,j,:), vicen(i,j,:), vsnon(i,j,:), &
	541	ticen(i,j,:,:), salin(i,j,:,:), &
	542	zvolpn(i,j,:), zvolp(i,j), &
	543	zapondn(i,j,:),zhpondn(i,j,:), zdvn)
	544	! outputs are
	545	! - zdvn
	546	! - zvolpn
	547	! - zvolp
	548	! - zapondn
	549	! - zhpondn
	550
	551	wfx_pnd(i,j) = wfx_pnd(i,j) + zdvn ! update flux from ponds to ocean
	552
[8060]	553	! mean surface temperature MV - why do we need that ? --> for the lid
	554
	555	! zTavg = z0
	556	! DO n = 1, jpl
	557	! zTavg = zTavg + zTsfcn(i,j,n)*aicen(i,j,n)
	558	! END DO
	559	! zTavg = zTavg / aice(i,j)
[7325]	560
	561	END DO ! ij
	562
	563	!---------------------------------------------------------------
	564	! Update pond volume and fraction
	565	!---------------------------------------------------------------
	566
	567	a_ip(:,:,:) = zapondn(:,:,:)
	568	v_ip(:,:,:) = zapondn(:,:,:) * zhpondn(:,:,:)
	569	a_ip_frac(:,:,:) = 0._wp
	570	h_ip (:,:,:) = 0._wp
	571
	572	END SUBROUTINE lim_mp_topo
	573
	574	SUBROUTINE lim_mp_area(aice,vice, &
	575	aicen, vicen, vsnon, ticen, &
	576	salin, zvolpn, zvolp, &
	577	zapondn,zhpondn,dvolp)
	578
	579	!!-------------------------------------------------------------------
	580	!! * ROUTINE lim_mp_area *
	581	!!
	582	!! ** Purpose : Given the total volume of meltwater, update
	583	!! pond fraction (a_ip) and depth (should be volume)
	584	!!
	585	!! **
	586	!!
	587	!!------------------------------------------------------------------
	588
	589	REAL (wp), INTENT(IN) :: &
	590	aice,vice
	591
	592	REAL (wp), DIMENSION(jpl), INTENT(IN) :: &
	593	aicen, vicen, vsnon
	594
	595	REAL (wp), DIMENSION(nlay_i,jpl), INTENT(IN) :: &
	596	ticen, salin
	597
	598	REAL (wp), DIMENSION(jpl), INTENT(INOUT) :: &
	599	zvolpn
	600
	601	REAL (wp), INTENT(INOUT) :: &
	602	zvolp, dvolp
	603
	604	REAL (wp), DIMENSION(jpl), INTENT(OUT) :: &
	605	zapondn, zhpondn
	606
	607	INTEGER :: &
	608	n, ns, &
	609	m_index, &
	610	permflag
	611
	612	REAL (wp), DIMENSION(jpl) :: &
	613	hicen, &
	614	hsnon, &
	615	asnon, &
	616	alfan, &
	617	betan, &
	618	cum_max_vol, &
	619	reduced_aicen
	620
	621	REAL (wp), DIMENSION(0:jpl) :: &
	622	cum_max_vol_tmp
	623
	624	REAL (wp) :: &
	625	hpond, &
	626	drain, &
	627	floe_weight, &
	628	pressure_head, &
	629	hsl_rel, &
	630	deltah, &
	631	perm, &
	632	msno
	633
	634	REAL (wp), parameter :: &
	635	viscosity = 1.79e-3_wp, & ! kinematic water viscosity in kg/m/s
	636	z0 = 0.0_wp , &
	637	c1 = 1.0_wp , &
	638	p4 = 0.4_wp , &
	639	p6 = 0.6_wp , &
	640	epsi10 = 1.0e-11_wp
	641
	642	!-----------\|
	643	! \|
	644	! \|-----------\|
	645	!___________\|___________\|______________________________________sea-level
	646	! \| \|
	647	! \| \|---^--------\|
	648	! \| \| \| \|
	649	! \| \| \| \|-----------\| \|-------
	650	! \| \| \|alfan(n)\| \| \|
	651	! \| \| \| \| \|--------------\|
	652	! \| \| \| \| \| \|
	653	!---------------------------v-------------------------------------------
	654	! \| \| ^ \| \| \|
	655	! \| \| \| \| \|--------------\|
	656	! \| \| \|betan(n)\| \| \|
	657	! \| \| \| \|-----------\| \|-------
	658	! \| \| \| \|
	659	! \| \|---v------- \|
	660	! \| \|
	661	! \|-----------\|
	662	! \|
	663	!-----------\|
	664
	665	!-------------------------------------------------------------------
	666	! initialize
	667	!-------------------------------------------------------------------
	668
	669	DO n = 1, jpl
	670
	671	zapondn(n) = z0
	672	zhpondn(n) = z0
	673
	674	!----------------------------------------
	675	! X) compute the effective snow fraction
	676	!----------------------------------------
	677	IF (aicen(n) < epsi10) THEN
	678	hicen(n) = z0
	679	hsnon(n) = z0
	680	reduced_aicen(n) = z0
	681	ELSE
	682	hicen(n) = vicen(n) / aicen(n)
	683	hsnon(n) = vsnon(n) / aicen(n)
	684	reduced_aicen(n) = c1 ! n=jpl
	685	IF (n < jpl) reduced_aicen(n) = aicen(n) &
	686	* (-0.024_wp*hicen(n) + 0.832_wp)
	687	asnon(n) = reduced_aicen(n) ! effective snow fraction (empirical)
[8060]	688	! MV should check whether this makes sense to have the same effective snow fraction in here
[7325]	689	END IF
	690
	691	! This choice for alfa and beta ignores hydrostatic equilibium of categories.
	692	! Hydrostatic equilibium of the entire ITD is accounted for below, assuming
	693	! a surface topography implied by alfa=0.6 and beta=0.4, and rigidity across all
	694	! categories. alfa and beta partition the ITD - they are areas not thicknesses!
	695	! Multiplying by hicen, alfan and betan (below) are thus volumes per unit area.
	696	! Here, alfa = 60% of the ice area (and since hice is constant in a category,
	697	! alfan = 60% of the ice volume) in each category lies above the reference line,
	698	! and 40% below. Note: p6 is an arbitrary choice, but alfa+beta=1 is required.
[8060]	699
	700	! MV:
	701	! Note that this choice is not in the original FF07 paper and has been adopted in CICE
	702	! No reason why is explained in the doc, but I guess there is a reason. I'll try to investigate, maybe
	703
	704	! Where does that choice come from
[7325]	705
[8060]	706	alfan(n) = 0.6 * hicen(n)
	707	betan(n) = 0.4 * hicen(n)
[7325]	708
	709	cum_max_vol(n) = z0
	710	cum_max_vol_tmp(n) = z0
	711
	712	END DO ! jpl
	713
	714	cum_max_vol_tmp(0) = z0
	715	drain = z0
	716	dvolp = z0
	717
	718	!----------------------------------------------------------
	719	! x) Drain overflow water, update pond fraction and volume
	720	!----------------------------------------------------------
	721
	722	!--------------------------------------------------------------------------
	723	! the maximum amount of water that can be contained up to each ice category
	724	!--------------------------------------------------------------------------
	725
	726	! MV
	727	! If melt ponds are too deep to be sustainable given the ITD (OVERFLOW)
	728	! Then the excess volume cum_max_vol(jl) drains out of the system
	729	! It should be added to wfx_pnd
	730	! END MV
	731
	732	DO n = 1, jpl-1 ! last category can not hold any volume
	733
	734	IF (alfan(n+1) >= alfan(n) .and. alfan(n+1) > z0) THEN
	735
	736	! total volume in level including snow
	737	cum_max_vol_tmp(n) = cum_max_vol_tmp(n-1) + &
	738	(alfan(n+1) - alfan(n)) * sum(reduced_aicen(1:n))
	739
	740	! subtract snow solid volumes from lower categories in current level
	741	DO ns = 1, n
	742	cum_max_vol_tmp(n) = cum_max_vol_tmp(n) &
	743	- rhosn/rhofw * & ! free air fraction that can be filled by water
	744	asnon(ns) * & ! effective areal fraction of snow in that category
	745	max(min(hsnon(ns)+alfan(ns)-alfan(n), alfan(n+1)- &
	746	alfan(n)), z0)
	747	END DO
	748
	749	ELSE ! assume higher categories unoccupied
	750	cum_max_vol_tmp(n) = cum_max_vol_tmp(n-1)
	751	END IF
	752	!IF (cum_max_vol_tmp(n) < z0) THEN
	753	! call abort_ice('negative melt pond volume')
	754	!END IF
	755	END DO
	756	cum_max_vol_tmp(jpl) = cum_max_vol_tmp(jpl-1) ! last category holds no volume
	757	cum_max_vol (1:jpl) = cum_max_vol_tmp(1:jpl)
	758
	759	!----------------------------------------------------------------
	760	! is there more meltwater than can be held in the floe?
	761	!----------------------------------------------------------------
	762	IF (zvolp >= cum_max_vol(jpl)) THEN
	763	drain = zvolp - cum_max_vol(jpl) + epsi10
	764	zvolp = zvolp - drain ! update meltwater volume available
	765	dvolp = drain ! this is the drained water
	766	IF (zvolp < epsi10) THEN
	767	dvolp = dvolp + zvolp
	768	zvolp = z0
	769	END IF
	770	END IF
	771
	772	! height and area corresponding to the remaining volume
	773
	774	! call calc_hpond(reduced_aicen, asnon, hsnon, rhos, alfan, &
	775	! zvolp, cum_max_vol, hpond, m_index)
	776
	777	DO n=1, m_index
	778	zhpondn(n) = hpond - alfan(n) + alfan(1) ! here oui choulde update
	779	! volume instead, no ?
	780	zapondn(n) = reduced_aicen(n)
	781	! in practise, pond fraction depends on the empirical snow fraction
	782	! so in turn on ice thickness
	783	END DO
	784
	785	!------------------------------------------------------------------------
	786	! Drainage through brine network (permeability)
	787	!------------------------------------------------------------------------
	788	!!! drainage due to ice permeability - Darcy's law
	789
	790	! sea water level
	791	msno = z0
	792	DO n=1,jpl
	793	msno = msno + vsnon(n) * rhosn
	794	END DO
	795	floe_weight = (msno + rhoicvice + rau0zvolp) / aice
	796	hsl_rel = floe_weight / rau0 &
	797	- ((sum(betan(:)*aicen(:))/aice) + alfan(1))
	798
	799	deltah = hpond - hsl_rel
	800	pressure_head = grav * rau0 * max(deltah, z0)
	801
	802	! drain IF ice is permeable
	803	permflag = 0
	804	IF (pressure_head > z0) THEN
	805	DO n = 1, jpl-1
	806	IF (hicen(n) /= z0) THEN
	807	perm = 0. ! MV ugly dummy patch
	808	CALL lim_mp_perm(ticen(:,n), salin(:,n), vicen(n), perm)
	809	IF (perm > z0) permflag = 1
	810
	811	drain = permzapondn(n)pressure_head*rdt_ice / &
	812	(viscosity*hicen(n))
	813	dvolp = dvolp + min(drain, zvolp)
	814	zvolp = max(zvolp - drain, z0)
	815	IF (zvolp < epsi10) THEN
	816	dvolp = dvolp + zvolp
	817	zvolp = z0
	818	END IF
	819	END IF
	820	END DO
	821
	822	! adjust melt pond DIMENSIONs
	823	IF (permflag > 0) THEN
	824	! recompute pond depth
	825	! CALL calc_hpond(reduced_aicen, asnon, hsnon, rhos, alfan, &
	826	! zvolp, cum_max_vol, hpond, m_index)
	827	DO n=1, m_index
	828	zhpondn(n) = hpond - alfan(n) + alfan(1)
	829	zapondn(n) = reduced_aicen(n)
	830	END DO
	831	END IF
	832	END IF ! pressure_head
	833
	834	!-------------------------------
	835	! X) remove water from the snow
	836	!-------------------------------
	837	!------------------------------------------------------------------------
	838	! total melt pond volume in category DOes not include snow volume
	839	! snow in melt ponds is not melted
	840	!------------------------------------------------------------------------
	841
	842	! Calculate pond volume for lower categories
	843	DO n=1,m_index-1
	844	zvolpn(n) = zapondn(n) * zhpondn(n) & ! what is not in the snow
	845	- (rhosn/rhofw) * asnon(n) * min(hsnon(n), zhpondn(n))
	846	END DO
	847
	848	! Calculate pond volume for highest category = remaining pond volume
	849
	850	! The following is completely unclear to Martin at least
	851	! Could we redefine properly and recode in a more readable way ?
	852
	853	! m_index = last category with melt pond
	854
	855	IF (m_index == 1) zvolpn(m_index) = zvolp ! volume of mw in 1st category is the total volume of melt water
	856
	857	IF (m_index > 1) THEN
	858	IF (zvolp > sum(zvolpn(1:m_index-1))) THEN
	859	zvolpn(m_index) = zvolp - sum(zvolpn(1:m_index-1)) !
	860	ELSE
	861	zvolpn(m_index) = z0
	862	zhpondn(m_index) = z0
	863	zapondn(m_index) = z0
	864	! If remaining pond volume is negative reduce pond volume of
	865	! lower category
	866	IF (zvolp+epsi10 < sum(zvolpn(1:m_index-1))) &
	867	zvolpn(m_index-1) = zvolpn(m_index-1)-sum(zvolpn(1:m_index-1))&
	868	+ zvolp
	869	END IF
	870	END IF
	871
	872	DO n=1,m_index
	873	IF (zapondn(n) > epsi10) THEN
	874	zhpondn(n) = zvolpn(n) / zapondn(n)
	875	ELSE
	876	dvolp = dvolp + zvolpn(n)
	877	zhpondn(n) = z0
	878	zvolpn(n) = z0
	879	zapondn(n) = z0
	880	end IF
	881	END DO
	882	DO n = m_index+1, jpl
	883	zhpondn(n) = z0
	884	zapondn(n) = z0
	885	zvolpn (n) = z0
	886	END DO
	887
	888	END SUBROUTINE lim_mp_area
	889
	890	!OLI_CODE
	891	!OLI_CODE
	892	!OLI_CODE SUBROUTINE calc_hpond(aicen, asnon, hsnon, rhos, alfan, &
	893	!OLI_CODE zvolp, cum_max_vol, &
	894	!OLI_CODE hpond, m_index)
	895	!OLI_CODE !!-------------------------------------------------------------------
	896	!OLI_CODE !! * ROUTINE calc_hpond *
	897	!OLI_CODE !!
	898	!OLI_CODE !! ** Purpose : Compute melt pond depth
	899	!OLI_CODE !!-------------------------------------------------------------------
	900	!OLI_CODE
	901	!OLI_CODE REAL (wp), DIMENSION(jpl), INTENT(IN) :: &
	902	!OLI_CODE aicen, &
	903	!OLI_CODE asnon, &
	904	!OLI_CODE hsnon, &
	905	!OLI_CODE rhos, &
	906	!OLI_CODE alfan, &
	907	!OLI_CODE cum_max_vol
	908	!OLI_CODE
	909	!OLI_CODE REAL (wp), INTENT(IN) :: &
	910	!OLI_CODE zvolp
	911	!OLI_CODE
	912	!OLI_CODE REAL (wp), INTENT(OUT) :: &
	913	!OLI_CODE hpond
	914	!OLI_CODE
	915	!OLI_CODE INTEGER, INTENT(OUT) :: &
	916	!OLI_CODE m_index
	917	!OLI_CODE
	918	!OLI_CODE INTEGER :: n, ns
	919	!OLI_CODE
	920	!OLI_CODE REAL (wp), DIMENSION(0:jpl+1) :: &
	921	!OLI_CODE hitl, &
	922	!OLI_CODE aicetl
	923	!OLI_CODE
	924	!OLI_CODE REAL (wp) :: &
	925	!OLI_CODE rem_vol, &
	926	!OLI_CODE area, &
	927	!OLI_CODE vol, &
	928	!OLI_CODE tmp, &
	929	!OLI_CODE z0 = 0.0_wp, &
	930	!OLI_CODE epsi10 = 1.0e-11_wp
	931	!OLI_CODE
	932	!OLI_CODE !----------------------------------------------------------------
	933	!OLI_CODE ! hpond is zero if zvolp is zero - have we fully drained?
	934	!OLI_CODE !----------------------------------------------------------------
	935	!OLI_CODE
	936	!OLI_CODE IF (zvolp < epsi10) THEN
	937	!OLI_CODE hpond = z0
	938	!OLI_CODE m_index = 0
	939	!OLI_CODE ELSE
	940	!OLI_CODE
	941	!OLI_CODE !----------------------------------------------------------------
	942	!OLI_CODE ! Calculate the category where water fills up to
	943	!OLI_CODE !----------------------------------------------------------------
	944	!OLI_CODE
	945	!OLI_CODE !----------\|
	946	!OLI_CODE ! \|
	947	!OLI_CODE ! \|
	948	!OLI_CODE ! \|----------\| -- --
	949	!OLI_CODE !__________\|__________\|_________________________________________ ^
	950	!OLI_CODE ! \| \| rem_vol ^ \| Semi-filled
	951	!OLI_CODE ! \| \|----------\|-- -- -- - ---\|-- ---- -- -- --v layer
	952	!OLI_CODE ! \| \| \| \|
	953	!OLI_CODE ! \| \| \| \|hpond
	954	!OLI_CODE ! \| \| \|----------\| \| \|-------
	955	!OLI_CODE ! \| \| \| \| \| \|
	956	!OLI_CODE ! \| \| \| \|---v-----\|
	957	!OLI_CODE ! \| \| m_index \| \| \|
	958	!OLI_CODE !-------------------------------------------------------------
	959	!OLI_CODE
	960	!OLI_CODE m_index = 0 ! 1:m_index categories have water in them
	961	!OLI_CODE DO n = 1, jpl
	962	!OLI_CODE IF (zvolp <= cum_max_vol(n)) THEN
	963	!OLI_CODE m_index = n
	964	!OLI_CODE IF (n == 1) THEN
	965	!OLI_CODE rem_vol = zvolp
	966	!OLI_CODE ELSE
	967	!OLI_CODE rem_vol = zvolp - cum_max_vol(n-1)
	968	!OLI_CODE END IF
	969	!OLI_CODE exit ! to break out of the loop
	970	!OLI_CODE END IF
	971	!OLI_CODE END DO
	972	!OLI_CODE m_index = min(jpl-1, m_index)
	973	!OLI_CODE
	974	!OLI_CODE !----------------------------------------------------------------
	975	!OLI_CODE ! semi-filled layer may have m_index different snow in it
	976	!OLI_CODE !----------------------------------------------------------------
	977	!OLI_CODE
	978	!OLI_CODE !----------------------------------------------------------- ^
	979	!OLI_CODE ! \| alfan(m_index+1)
	980	!OLI_CODE ! \|
	981	!OLI_CODE !hitl(3)--> \|----------\| \|
	982	!OLI_CODE !hitl(2)--> \|------------\| * * * * *\| \|
	983	!OLI_CODE !hitl(1)--> \|----------\|* * * * * * \|* * * * * \| \|
	984	!OLI_CODE !hitl(0)-->------------------------------------------------- \| ^
	985	!OLI_CODE ! various snow from lower categories \| \|alfa(m_index)
	986	!OLI_CODE
	987	!OLI_CODE ! hitl - heights of the snow layers from thinner and current categories
	988	!OLI_CODE ! aicetl - area of each snow depth in this layer
	989	!OLI_CODE
	990	!OLI_CODE hitl(:) = z0
	991	!OLI_CODE aicetl(:) = z0
	992	!OLI_CODE DO n = 1, m_index
	993	!OLI_CODE hitl(n) = max(min(hsnon(n) + alfan(n) - alfan(m_index), &
	994	!OLI_CODE alfan(m_index+1) - alfan(m_index)), z0)
	995	!OLI_CODE aicetl(n) = asnon(n)
	996	!OLI_CODE
	997	!OLI_CODE aicetl(0) = aicetl(0) + (aicen(n) - asnon(n))
	998	!OLI_CODE END DO
	999	!OLI_CODE hitl(m_index+1) = alfan(m_index+1) - alfan(m_index)
	1000	!OLI_CODE aicetl(m_index+1) = z0
	1001	!OLI_CODE
	1002	!OLI_CODE !----------------------------------------------------------------
	1003	!OLI_CODE ! reorder array according to hitl
	1004	!OLI_CODE ! snow heights not necessarily in height order
	1005	!OLI_CODE !----------------------------------------------------------------
	1006	!OLI_CODE
	1007	!OLI_CODE DO ns = 1, m_index+1
	1008	!OLI_CODE DO n = 0, m_index - ns + 1
	1009	!OLI_CODE IF (hitl(n) > hitl(n+1)) THEN ! swap order
	1010	!OLI_CODE tmp = hitl(n)
	1011	!OLI_CODE hitl(n) = hitl(n+1)
	1012	!OLI_CODE hitl(n+1) = tmp
	1013	!OLI_CODE tmp = aicetl(n)
	1014	!OLI_CODE aicetl(n) = aicetl(n+1)
	1015	!OLI_CODE aicetl(n+1) = tmp
	1016	!OLI_CODE END IF
	1017	!OLI_CODE END DO
	1018	!OLI_CODE END DO
	1019	!OLI_CODE
	1020	!OLI_CODE !----------------------------------------------------------------
	1021	!OLI_CODE ! divide semi-filled layer into set of sublayers each vertically homogenous
	1022	!OLI_CODE !----------------------------------------------------------------
	1023	!OLI_CODE
	1024	!OLI_CODE !hitl(3)----------------------------------------------------------------
	1025	!OLI_CODE ! \| * * * * * * * *
	1026	!OLI_CODE ! \|* * * * * * * * *
	1027	!OLI_CODE !hitl(2)----------------------------------------------------------------
	1028	!OLI_CODE ! \| * * * * * * * * \| * * * * * * * *
	1029	!OLI_CODE ! \|* * * * * * * * * \|* * * * * * * * *
	1030	!OLI_CODE !hitl(1)----------------------------------------------------------------
	1031	!OLI_CODE ! \| * * * * * * * * \| * * * * * * * * \| * * * * * * * *
	1032	!OLI_CODE ! \|* * * * * * * * * \|* * * * * * * * * \|* * * * * * * * *
	1033	!OLI_CODE !hitl(0)----------------------------------------------------------------
	1034	!OLI_CODE ! aicetl(0) aicetl(1) aicetl(2) aicetl(3)
	1035	!OLI_CODE
	1036	!OLI_CODE ! move up over layers incrementing volume
	1037	!OLI_CODE DO n = 1, m_index+1
	1038	!OLI_CODE
	1039	!OLI_CODE area = sum(aicetl(:)) - & ! total area of sub-layer
	1040	!OLI_CODE (rhos(n)/rau0) * sum(aicetl(n:jpl+1)) ! area of sub-layer occupied by snow
	1041	!OLI_CODE
	1042	!OLI_CODE vol = (hitl(n) - hitl(n-1)) * area ! thickness of sub-layer times area
	1043	!OLI_CODE
	1044	!OLI_CODE IF (vol >= rem_vol) THEN ! have reached the sub-layer with the depth within
	1045	!OLI_CODE hpond = rem_vol / area + hitl(n-1) + alfan(m_index) - &
	1046	!OLI_CODE alfan(1)
	1047	!OLI_CODE exit
	1048	!OLI_CODE ELSE ! still in sub-layer below the sub-layer with the depth
	1049	!OLI_CODE rem_vol = rem_vol - vol
	1050	!OLI_CODE END IF
	1051	!OLI_CODE
	1052	!OLI_CODE END DO
	1053	!OLI_CODE
	1054	!OLI_CODE END IF
	1055	!OLI_CODE
	1056	!OLI_CODE END SUBROUTINE calc_hpond
	1057	!OLI_CODE
	1058	!OLI_CODE
	1059	SUBROUTINE lim_mp_perm(ticen, salin, vicen, perm)
	1060	!!-------------------------------------------------------------------
	1061	!! * ROUTINE lim_mp_perm *
	1062	!!
	1063	!! ** Purpose : Determine the liquid fraction of brine in the ice
	1064	!! and its permeability
	1065	!!-------------------------------------------------------------------
	1066	REAL (wp), DIMENSION(nlay_i), INTENT(IN) :: &
	1067	ticen, & ! energy of melting for each ice layer (J/m2)
	1068	salin
	1069
	1070	REAL (wp), INTENT(IN) :: &
	1071	vicen ! ice volume
	1072
	1073	REAL (wp), INTENT(OUT) :: &
	1074	perm ! permeability
	1075
	1076	REAL (wp) :: &
	1077	Sbr ! brine salinity
	1078
	1079	REAL (wp), DIMENSION(nlay_i) :: &
	1080	Tin, & ! ice temperature
	1081	phi ! liquid fraction
	1082
	1083	INTEGER :: k
	1084
	1085	REAL (wp) :: &
	1086	c2 = 2.0_wp
	1087
	1088	!-----------------------------------------------------------------
	1089	! Compute ice temperatures from enthalpies using quadratic formula
	1090	!-----------------------------------------------------------------
	1091
	1092	DO k = 1,nlay_i
	1093	Tin(k) = ticen(k)
	1094	END DO
	1095
	1096	!-----------------------------------------------------------------
	1097	! brine salinity and liquid fraction
	1098	!-----------------------------------------------------------------
	1099
	1100	IF (maxval(Tin-rtt) <= -c2) THEN
	1101
	1102	DO k = 1,nlay_i
	1103	Sbr = - 1.2_wp &
	1104	-21.8_wp * (Tin(k)-rtt) &
	1105	- 0.919_wp * (Tin(k)-rtt)**2 &
	1106	- 0.01878_wp * (Tin(k)-rtt)**3
	1107	phi(k) = salin(k)/Sbr ! liquid fraction
	1108	END DO ! k
	1109
	1110	ELSE
	1111
	1112	DO k = 1,nlay_i
	1113	Sbr = -17.6_wp * (Tin(k)-rtt) &
	1114	- 0.389_wp * (Tin(k)-rtt)**2 &
	1115	- 0.00362_wp* (Tin(k)-rtt)**3
	1116	phi(k) = salin(k)/Sbr ! liquid fraction
	1117	END DO
	1118
	1119	END IF
	1120
	1121	!-----------------------------------------------------------------
	1122	! permeability
	1123	!-----------------------------------------------------------------
	1124
	1125	perm = 3.0e-08_wp * (minval(phi))**3 ! REFERENCE PLEASE (this fucking
	1126	! bastard of Golden)
	1127
	1128	END SUBROUTINE lim_mp_perm
	1129	!OLI_CODE
	1130	!OLI_CODE #else
	1131	!OLI_CODE !!----------------------------------------------------------------------
	1132	!OLI_CODE !! Default option Dummy Module No LIM-3 sea-ice model
	1133	!OLI_CODE !!----------------------------------------------------------------------
	1134	!OLI_CODE CONTAINS
	1135	!OLI_CODE SUBROUTINE lim_mp_init ! Empty routine
	1136	!OLI_CODE END SUBROUTINE lim_mp_init
	1137	!OLI_CODE SUBROUTINE lim_mp ! Empty routine
	1138	!OLI_CODE END SUBROUTINE lim_mp
	1139	!OLI_CODE SUBROUTINE compute_mp_topo ! Empty routine
	1140	!OLI_CODE END SUBROUTINE compute_mp_topo
	1141	!OLI_CODE SUBROUTINE pond_area ! Empty routine
	1142	!OLI_CODE END SUBROUTINE pond_area
	1143	!OLI_CODE SUBROUTINE calc_hpond ! Empty routine
	1144	!OLI_CODE END SUBROUTINE calc_hpond
	1145	!OLI_CODE SUBROUTINE permeability_phy ! Empty routine
	1146	!OLI_CODE END SUBROUTINE permeability_phy
	1147	!OLI_CODE #endif
	1148	!OLI_CODE !!======================================================================
	1149	!OLI_CODE END MODULE limmp_topo
	1150
	1151
[7293]	1152	!OLI_CODE MODULE limmp_topo
	1153	!OLI_CODE !!======================================================================
	1154	!OLI_CODE !! * MODULE limmp_topo *
	1155	!OLI_CODE !! LIM-3 sea-ice : computation of melt ponds' properties
	1156	!OLI_CODE !!======================================================================
	1157	!OLI_CODE !! History : Original code by Daniela Flocco and Adrian Turner
	1158	!OLI_CODE !! ! 2012-09 (O. Lecomte) Adaptation for routine inclusion in
	1159	!OLI_CODE !! NEMO-LIM3.1
	1160	!OLI_CODE !! ! 2016-11 (O. Lecomte, C. Rousset, M. Vancoppenolle)
	1161	!OLI_CODE !! Adaptation for merge with NEMO-LIM3.6
	1162	!OLI_CODE !!----------------------------------------------------------------------
	1163	!OLI_CODE #if defined key_lim3
	1164	!OLI_CODE !!----------------------------------------------------------------------
	1165	!OLI_CODE !! 'key_lim3' LIM-3 sea-ice model
	1166	!OLI_CODE !!----------------------------------------------------------------------
	1167	!OLI_CODE !! lim_mp_init : melt pond properties initialization
	1168	!OLI_CODE !! lim_mp : melt pond routine caller
	1169	!OLI_CODE !! compute_mp_topo : Actual melt pond routine
	1170	!OLI_CODE !!----------------------------------------------------------------------
	1171	!OLI_CODE USE ice_oce, ONLY: rdt_ice, tatm_ice
	1172	!OLI_CODE USE phycst
	1173	!OLI_CODE USE dom_ice
	1174	!OLI_CODE USE dom_oce
	1175	!OLI_CODE USE sbc_oce
	1176	!OLI_CODE USE sbc_ice
	1177	!OLI_CODE USE par_ice
	1178	!OLI_CODE USE par_oce
	1179	!OLI_CODE USE ice
	1180	!OLI_CODE USE thd_ice
	1181	!OLI_CODE USE in_out_manager
	1182	!OLI_CODE USE lbclnk
	1183	!OLI_CODE USE lib_mpp
	1184	!OLI_CODE
	1185	!OLI_CODE IMPLICIT NONE
	1186	!OLI_CODE PRIVATE
	1187	!OLI_CODE
	1188	!OLI_CODE PUBLIC lim_mp_init
	1189	!OLI_CODE PUBLIC lim_mp
	1190	!OLI_CODE
	1191	!OLI_CODE CONTAINS
	1192	!OLI_CODE
	1193	!OLI_CODE SUBROUTINE lim_mp_init
	1194	!OLI_CODE !!-------------------------------------------------------------------
	1195	!OLI_CODE !! * ROUTINE lim_mp_init *
	1196	!OLI_CODE !!
	1197	!OLI_CODE !! ** Purpose : Initialize melt ponds
	1198	!OLI_CODE !!-------------------------------------------------------------------
	1199	!OLI_CODE a_ip_frac(:,:,:) = 0._wp
	1200	!OLI_CODE a_ip(:,:,:) = 0._wp
	1201	!OLI_CODE h_ip(:,:,:) = 0._wp
	1202	!OLI_CODE v_ip(:,:,:) = 0._wp
	1203	!OLI_CODE h_il(:,:,:) = 0._wp
	1204	!OLI_CODE v_il(:,:,:) = 0._wp
	1205	!OLI_CODE
	1206	!OLI_CODE END SUBROUTINE lim_mp_init
	1207	!OLI_CODE
	1208	!OLI_CODE
	1209	!OLI_CODE SUBROUTINE lim_mp
	1210	!OLI_CODE !!-------------------------------------------------------------------
	1211	!OLI_CODE !! * ROUTINE lim_mp *
	1212	!OLI_CODE !!
	1213	!OLI_CODE !! ** Purpose : Compute surface heat flux and call main melt pond
	1214	!OLI_CODE !! routine
	1215	!OLI_CODE !!-------------------------------------------------------------------
	1216	!OLI_CODE
	1217	!OLI_CODE INTEGER :: ji, jj, jl ! dummy loop indices
	1218	!OLI_CODE
	1219	!OLI_CODE fsurf(:,:) = 0.e0
	1220	!OLI_CODE DO jl = 1, jpl
	1221	!OLI_CODE DO jj = 1, jpj
	1222	!OLI_CODE DO ji = 1, jpi
	1223	!OLI_CODE fsurf(ji,jj) = fsurf(ji,jj) + a_i(ji,jj,jl) * &
	1224	!OLI_CODE (qns_ice(ji,jj,jl) + (1.0 - izero(ji,jj,jl)) &
	1225	!OLI_CODE * qsr_ice(ji,jj,jl))
	1226	!OLI_CODE END DO
	1227	!OLI_CODE END DO
	1228	!OLI_CODE END DO
	1229	!OLI_CODE
	1230	!OLI_CODE CALL compute_mp_topo(at_i, a_i, &
	1231	!OLI_CODE vt_i, v_i, v_s, rhosn_glo, t_i, s_i, a_ip_frac, &
	1232	!OLI_CODE h_ip, h_il, t_su, tatm_ice, diag_sur_me*rdt_ice, &
	1233	!OLI_CODE fsurf, fwoc)
	1234	!OLI_CODE
	1235	!OLI_CODE at_ip(:,:) = 0.0
	1236	!OLI_CODE vt_ip(:,:) = 0.0
	1237	!OLI_CODE vt_il(:,:) = 0.0
	1238	!OLI_CODE DO jl = 1, jpl
	1239	!OLI_CODE DO jj = 1, jpj
	1240	!OLI_CODE DO ji = 1, jpi
	1241	!OLI_CODE a_ip(ji,jj,jl) = MAX(0.0_wp, a_ip_frac(ji,jj,jl) * &
	1242	!OLI_CODE a_i(ji,jj,jl))
	1243	!OLI_CODE v_ip(ji,jj,jl) = MAX(0.0_wp, a_ip_frac(ji,jj,jl) * &
	1244	!OLI_CODE a_i(ji,jj,jl) * h_ip(ji,jj,jl))
	1245	!OLI_CODE v_il(ji,jj,jl) = MAX(0.0_wp, a_ip_frac(ji,jj,jl) * &
	1246	!OLI_CODE a_i(ji,jj,jl) * h_il(ji,jj,jl))
	1247	!OLI_CODE at_ip(ji,jj) = at_ip(ji,jj) + a_ip(ji,jj,jl)
	1248	!OLI_CODE vt_ip(ji,jj) = vt_ip(ji,jj) + v_ip(ji,jj,jl)
	1249	!OLI_CODE vt_il(ji,jj) = vt_il(ji,jj) + v_il(ji,jj,jl)
	1250	!OLI_CODE END DO
	1251	!OLI_CODE END DO
	1252	!OLI_CODE END DO
	1253	!OLI_CODE
	1254	!OLI_CODE END SUBROUTINE lim_mp
	1255	!OLI_CODE
	1256	!OLI_CODE
	1257	!OLI_CODE SUBROUTINE compute_mp_topo(aice, aicen, &
	1258	!OLI_CODE vice, vicen, &
	1259	!OLI_CODE vsnon, rhos, &
	1260	!OLI_CODE ticen, salin, &
	1261	!OLI_CODE a_ip_frac, h_ip, &
	1262	!OLI_CODE h_il, Tsfc, &
	1263	!OLI_CODE potT, meltt, &
	1264	!OLI_CODE fsurf, fwoc)
	1265	!OLI_CODE !!-------------------------------------------------------------------
	1266	!OLI_CODE !! * ROUTINE compute_mp_topo *
	1267	!OLI_CODE !!
	1268	!OLI_CODE !! ** Purpose : Compute melt pond evolution based on the ice
	1269	!OLI_CODE !! topography as inferred from the ice thickness
	1270	!OLI_CODE !! distribution.
	1271	!OLI_CODE !!
	1272	!OLI_CODE !! ** Method : This code is initially based on Flocco and Feltham
	1273	!OLI_CODE !! (2007) and Flocco et al. (2010). More to come...
	1274	!OLI_CODE !!
	1275	!OLI_CODE !! ** Tunable parameters :
	1276	!OLI_CODE !!
	1277	!OLI_CODE !! ** Note :
	1278	!OLI_CODE !!
	1279	!OLI_CODE !! ** References
	1280	!OLI_CODE !! Flocco, D. and D. L. Feltham, 2007. A continuum model of melt pond
	1281	!OLI_CODE !! evolution on Arctic sea ice. J. Geophys. Res. 112, C08016, doi:
	1282	!OLI_CODE !! 10.1029/2006JC003836.
	1283	!OLI_CODE !! Flocco, D., D. L. Feltham and A. K. Turner, 2010. Incorporation of
	1284	!OLI_CODE !! a physically based melt pond scheme into the sea ice component of a
	1285	!OLI_CODE !! climate model. J. Geophys. Res. 115, C08012,
	1286	!OLI_CODE !! doi: 10.1029/2009JC005568.
	1287	!OLI_CODE !!
	1288	!OLI_CODE !!-------------------------------------------------------------------
	1289	!OLI_CODE
	1290	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj), &
	1291	!OLI_CODE INTENT(IN) :: &
	1292	!OLI_CODE aice, & ! total ice area fraction
	1293	!OLI_CODE vice ! total ice volume (m)
	1294	!OLI_CODE
	1295	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj,jpl), &
	1296	!OLI_CODE INTENT(IN) :: &
	1297	!OLI_CODE aicen, & ! ice area fraction, per category
	1298	!OLI_CODE vsnon, & ! snow volume, per category (m)
	1299	!OLI_CODE rhos, & ! equivalent snow density, per category (kg/m^3)
	1300	!OLI_CODE vicen ! ice volume, per category (m)
	1301	!OLI_CODE
	1302	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj,nlay_i,jpl), &
	1303	!OLI_CODE INTENT(IN) :: &
	1304	!OLI_CODE ticen, & ! ice enthalpy, per category
	1305	!OLI_CODE salin
	1306	!OLI_CODE
	1307	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj,jpl), &
	1308	!OLI_CODE INTENT(INOUT) :: &
	1309	!OLI_CODE a_ip_frac , & ! pond area fraction of ice, per ice category
	1310	!OLI_CODE h_ip , & ! pond depth, per ice category (m)
	1311	!OLI_CODE h_il ! Refrozen ice lid thickness, per ice category (m)
	1312	!OLI_CODE
	1313	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj), &
	1314	!OLI_CODE INTENT(IN) :: &
	1315	!OLI_CODE potT, & ! air potential temperature
	1316	!OLI_CODE meltt, & ! total surface meltwater flux
	1317	!OLI_CODE fsurf ! thermodynamic heat flux at ice/snow surface (W/m^2)
	1318	!OLI_CODE
	1319	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj), &
	1320	!OLI_CODE INTENT(INOUT) :: &
	1321	!OLI_CODE fwoc ! fresh water flux to the ocean (from draining and other pond volume adjustments)
	1322	!OLI_CODE ! (m)
	1323	!OLI_CODE
	1324	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj,jpl), &
	1325	!OLI_CODE INTENT(IN) :: &
	1326	!OLI_CODE Tsfc ! snow/sea ice surface temperature
	1327	!OLI_CODE
	1328	!OLI_CODE ! local variables
	1329	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj,jpl) :: &
	1330	!OLI_CODE zTsfcn, & ! ice/snow surface temperature (C)
	1331	!OLI_CODE zvolpn, & ! pond volume per unit area, per category (m)
	1332	!OLI_CODE zvuin ! water-equivalent volume of ice lid on melt pond ('upper ice', m)
	1333	!OLI_CODE
	1334	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj,jpl) :: &
	1335	!OLI_CODE zapondn,& ! pond area fraction, per category
	1336	!OLI_CODE zhpondn ! pond depth, per category (m)
	1337	!OLI_CODE
	1338	!OLI_CODE REAL (wp), DIMENSION (jpi,jpj) :: &
	1339	!OLI_CODE zvolp ! total volume of pond, per unit area of pond (m)
	1340	!OLI_CODE
	1341	!OLI_CODE REAL (wp) :: &
	1342	!OLI_CODE zhi, & ! ice thickness (m)
	1343	!OLI_CODE zdHui, & ! change in thickness of ice lid (m)
	1344	!OLI_CODE zomega, & ! conduction
	1345	!OLI_CODE zdTice, & ! temperature difference across ice lid (C)
	1346	!OLI_CODE zdvice, & ! change in ice volume (m)
	1347	!OLI_CODE zTavg, & ! mean surface temperature across categories (C)
	1348	!OLI_CODE zTp, & ! pond freezing temperature (C)
	1349	!OLI_CODE zdvn ! change in melt pond volume for fresh water budget
	1350	!OLI_CODE INTEGER, DIMENSION (jpi*jpj) :: &
	1351	!OLI_CODE indxi, indxj ! compressed indices for cells with ice melting
	1352	!OLI_CODE
	1353	!OLI_CODE INTEGER :: n,k,i,j,ij,icells,indxij ! loop indices
	1354	!OLI_CODE
	1355	!OLI_CODE INTEGER, DIMENSION (jpl) :: &
	1356	!OLI_CODE kcells ! cells where ice lid combines with vice
	1357	!OLI_CODE
	1358	!OLI_CODE INTEGER, DIMENSION (jpi*jpj,jpl) :: &
	1359	!OLI_CODE indxii, indxjj ! i,j indices for kcells loop
	1360	!OLI_CODE
	1361	!OLI_CODE REAL (wp), parameter :: &
	1362	!OLI_CODE zhicemin = 0.1_wp , & ! minimum ice thickness with ponds (m)
	1363	!OLI_CODE zTd = 0.15_wp, & ! temperature difference for freeze-up (C)
	1364	!OLI_CODE zr1_rlfus = 1._wp / 0.334e+6 / 917._wp , & ! (J/m^3)
	1365	!OLI_CODE zmin_volp = 1.e-4_wp, & ! minimum pond volume (m)
	1366	!OLI_CODE z0 = 0._wp, &
	1367	!OLI_CODE zTimelt = 0._wp, &
	1368	!OLI_CODE z01 = 0.01_wp, &
	1369	!OLI_CODE z25 = 0.25_wp, &
	1370	!OLI_CODE z5 = 0.5_wp, &
[7325]	1371	!OLI_CODE epsi10 = 1.0e-11_wp
[7293]	1372	!OLI_CODE !---------------------------------------------------------------
	1373	!OLI_CODE ! initialize
	1374	!OLI_CODE !---------------------------------------------------------------
	1375	!OLI_CODE
	1376	!OLI_CODE DO j = 1, jpj
	1377	!OLI_CODE DO i = 1, jpi
	1378	!OLI_CODE zvolp(i,j) = z0
	1379	!OLI_CODE END DO
	1380	!OLI_CODE END DO
	1381	!OLI_CODE DO n = 1, jpl
	1382	!OLI_CODE DO j = 1, jpj
	1383	!OLI_CODE DO i = 1, jpi
	1384	!OLI_CODE ! load tracers
	1385	!OLI_CODE zvolp(i,j) = zvolp(i,j) + h_ip(i,j,n) &
	1386	!OLI_CODE * a_ip_frac(i,j,n) * aicen(i,j,n)
	1387	!OLI_CODE zTsfcn(i,j,n) = Tsfc(i,j,n) - rtt ! convert in Celsius - Oli
	1388	!OLI_CODE zvuin (i,j,n) = h_il(i,j,n) &
	1389	!OLI_CODE * a_ip_frac(i,j,n) * aicen(i,j,n)
	1390	!OLI_CODE
	1391	!OLI_CODE zhpondn(i,j,n) = z0 ! pond depth, per category
	1392	!OLI_CODE zapondn(i,j,n) = z0 ! pond area, per category
	1393	!OLI_CODE END DO
	1394	!OLI_CODE END DO
	1395	!OLI_CODE indxii(:,n) = 0
	1396	!OLI_CODE indxjj(:,n) = 0
	1397	!OLI_CODE kcells (n) = 0
	1398	!OLI_CODE END DO
	1399	!OLI_CODE
	1400	!OLI_CODE ! The freezing temperature for meltponds is assumed slightly below 0C,
	1401	!OLI_CODE ! as if meltponds had a little salt in them. The salt budget is not
	1402	!OLI_CODE ! altered for meltponds, but if it were then an actual pond freezing
	1403	!OLI_CODE ! temperature could be computed.
	1404	!OLI_CODE
	1405	!OLI_CODE zTp = zTimelt - zTd
	1406	!OLI_CODE
	1407	!OLI_CODE !-----------------------------------------------------------------
	1408	!OLI_CODE ! Identify grid cells with ponds
	1409	!OLI_CODE !-----------------------------------------------------------------
	1410	!OLI_CODE
	1411	!OLI_CODE icells = 0
	1412	!OLI_CODE DO j = 1, jpj
	1413	!OLI_CODE DO i = 1, jpi
	1414	!OLI_CODE zhi = z0
[7325]	1415	!OLI_CODE IF (aice(i,j) > epsi10) zhi = vice(i,j)/aice(i,j)
[7293]	1416	!OLI_CODE IF ( aice(i,j) > z01 .and. zhi > zhicemin .and. &
	1417	!OLI_CODE zvolp(i,j) > zmin_volp*aice(i,j)) THEN
	1418	!OLI_CODE icells = icells + 1
	1419	!OLI_CODE indxi(icells) = i
	1420	!OLI_CODE indxj(icells) = j
	1421	!OLI_CODE ELSE ! remove ponds on thin ice
	1422	!OLI_CODE !fpond(i,j) = fpond(i,j) - zvolp(i,j)
	1423	!OLI_CODE zvolpn(i,j,:) = z0
	1424	!OLI_CODE zvuin (i,j,:) = z0
	1425	!OLI_CODE zvolp (i,j) = z0
	1426	!OLI_CODE END IF
	1427	!OLI_CODE END DO ! i
	1428	!OLI_CODE END DO ! j
	1429	!OLI_CODE
	1430	!OLI_CODE DO ij = 1, icells
	1431	!OLI_CODE i = indxi(ij)
	1432	!OLI_CODE j = indxj(ij)
	1433	!OLI_CODE
	1434	!OLI_CODE !--------------------------------------------------------------
	1435	!OLI_CODE ! calculate pond area and depth
	1436	!OLI_CODE !--------------------------------------------------------------
	1437	!OLI_CODE CALL pond_area(aice(i,j),vice(i,j),rhos(i,j,:), &
	1438	!OLI_CODE aicen(i,j,:), vicen(i,j,:), vsnon(i,j,:), &
	1439	!OLI_CODE ticen(i,j,:,:), salin(i,j,:,:), &
	1440	!OLI_CODE zvolpn(i,j,:), zvolp(i,j), &
	1441	!OLI_CODE zapondn(i,j,:),zhpondn(i,j,:), zdvn)
	1442	!OLI_CODE
	1443	!OLI_CODE fwoc(i,j) = fwoc(i,j) + zdvn ! -> Goes to fresh water budget
	1444	!OLI_CODE
	1445	!OLI_CODE ! mean surface temperature
	1446	!OLI_CODE zTavg = z0
	1447	!OLI_CODE DO n = 1, jpl
	1448	!OLI_CODE zTavg = zTavg + zTsfcn(i,j,n)*aicen(i,j,n)
	1449	!OLI_CODE END DO
	1450	!OLI_CODE zTavg = zTavg / aice(i,j)
	1451	!OLI_CODE
	1452	!OLI_CODE DO n = 1, jpl-1
	1453	!OLI_CODE
[7325]	1454	!OLI_CODE IF (zvuin(i,j,n) > epsi10) THEN
[7293]	1455	!OLI_CODE
	1456	!OLI_CODE !----------------------------------------------------------------
	1457	!OLI_CODE ! melting: floating upper ice layer melts in whole or part
	1458	!OLI_CODE !----------------------------------------------------------------
	1459	!OLI_CODE ! IF (zTsfcn(i,j,n) > zTp) THEN
	1460	!OLI_CODE IF (zTavg > zTp) THEN
	1461	!OLI_CODE
	1462	!OLI_CODE zdvice = min(meltt(i,j)*zapondn(i,j,n), zvuin(i,j,n))
[7325]	1463	!OLI_CODE IF (zdvice > epsi10) THEN
[7293]	1464	!OLI_CODE zvuin (i,j,n) = zvuin (i,j,n) - zdvice
	1465	!OLI_CODE zvolpn(i,j,n) = zvolpn(i,j,n) + zdvice
	1466	!OLI_CODE zvolp (i,j) = zvolp (i,j) + zdvice
	1467	!OLI_CODE !fwoc(i,j) = fwoc(i,j) + zdvice
	1468	!OLI_CODE
[7325]	1469	!OLI_CODE IF (zvuin(i,j,n) < epsi10 .and. zvolpn(i,j,n) > puny) THEN
[7293]	1470	!OLI_CODE ! ice lid melted and category is pond covered
	1471	!OLI_CODE zvolpn(i,j,n) = zvolpn(i,j,n) + zvuin(i,j,n)
	1472	!OLI_CODE !fwoc(i,j) = fwoc(i,j) + zvuin(i,j,n)
	1473	!OLI_CODE zvuin(i,j,n) = z0
	1474	!OLI_CODE END IF
	1475	!OLI_CODE zhpondn(i,j,n) = zvolpn(i,j,n) / zapondn(i,j,n)
	1476	!OLI_CODE END IF
	1477	!OLI_CODE
	1478	!OLI_CODE !----------------------------------------------------------------
	1479	!OLI_CODE ! freezing: existing upper ice layer grows
	1480	!OLI_CODE !----------------------------------------------------------------
[7325]	1481	!OLI_CODE ELSE IF (zvolpn(i,j,n) > epsi10) THEN ! zTavg <= zTp
[7293]	1482	!OLI_CODE
	1483	!OLI_CODE ! dIFferential growth of base of surface floating ice layer
	1484	!OLI_CODE zdTice = max(-zTavg, z0) ! > 0
	1485	!OLI_CODE zomega = rcdiczdTice zr1_rlfus
	1486	!OLI_CODE zdHui = sqrt(zomegardt_ice + z25(zvuin(i,j,n)/ &
	1487	!OLI_CODE aicen(i,j,n))*2)- z5 zvuin(i,j,n)/aicen(i,j,n)
	1488	!OLI_CODE
	1489	!OLI_CODE zdvice = min(zdHui*zapondn(i,j,n), zvolpn(i,j,n))
[7325]	1490	!OLI_CODE IF (zdvice > epsi10) THEN
[7293]	1491	!OLI_CODE zvuin (i,j,n) = zvuin (i,j,n) + zdvice
	1492	!OLI_CODE zvolpn(i,j,n) = zvolpn(i,j,n) - zdvice
	1493	!OLI_CODE zvolp (i,j) = zvolp (i,j) - zdvice
	1494	!OLI_CODE !fwoc(i,j) = fwoc(i,j) - zdvice
	1495	!OLI_CODE zhpondn(i,j,n) = zvolpn(i,j,n) / zapondn(i,j,n)
	1496	!OLI_CODE END IF
	1497	!OLI_CODE
	1498	!OLI_CODE END IF ! zTavg
	1499	!OLI_CODE
	1500	!OLI_CODE !----------------------------------------------------------------
	1501	!OLI_CODE ! freezing: upper ice layer begins to form
	1502	!OLI_CODE ! note: albedo does not change
	1503	!OLI_CODE !----------------------------------------------------------------
[7325]	1504	!OLI_CODE ELSE ! zvuin < epsi10
[7293]	1505	!OLI_CODE
	1506	!OLI_CODE ! thickness of newly formed ice
	1507	!OLI_CODE ! the surface temperature of a meltpond is the same as that
	1508	!OLI_CODE ! of the ice underneath (0C), and the thermodynamic surface
	1509	!OLI_CODE ! flux is the same
	1510	!OLI_CODE zdHui = max(-fsurf(i,j)rdt_icezr1_rlfus, z0)
	1511	!OLI_CODE zdvice = min(zdHui*zapondn(i,j,n), zvolpn(i,j,n))
[7325]	1512	!OLI_CODE IF (zdvice > epsi10) THEN
[7293]	1513	!OLI_CODE zvuin (i,j,n) = zdvice
	1514	!OLI_CODE zvolpn(i,j,n) = zvolpn(i,j,n) - zdvice
	1515	!OLI_CODE zvolp (i,j) = zvolp (i,j) - zdvice
	1516	!OLI_CODE !fwoc(i,j) = fwoc(i,j) - zdvice
	1517	!OLI_CODE zhpondn(i,j,n)= zvolpn(i,j,n) / zapondn(i,j,n)
	1518	!OLI_CODE END IF
	1519	!OLI_CODE
	1520	!OLI_CODE END IF ! zvuin
	1521	!OLI_CODE
	1522	!OLI_CODE END DO ! jpl
	1523	!OLI_CODE
	1524	!OLI_CODE END DO ! ij
	1525	!OLI_CODE
	1526	!OLI_CODE !---------------------------------------------------------------
	1527	!OLI_CODE ! remove ice lid if there is no liquid pond
	1528	!OLI_CODE ! zvuin may be nonzero on category jpl due to dynamics
	1529	!OLI_CODE !---------------------------------------------------------------
	1530	!OLI_CODE
	1531	!OLI_CODE DO j = 1, jpj
	1532	!OLI_CODE DO i = 1, jpi
	1533	!OLI_CODE DO n = 1, jpl
[7325]	1534	!OLI_CODE IF (aicen(i,j,n) > epsi10 .and. zvolpn(i,j,n) < puny &
	1535	!OLI_CODE .and. zvuin (i,j,n) > epsi10) THEN
[7293]	1536	!OLI_CODE kcells(n) = kcells(n) + 1
	1537	!OLI_CODE indxij = kcells(n)
	1538	!OLI_CODE indxii(indxij,n) = i
	1539	!OLI_CODE indxjj(indxij,n) = j
	1540	!OLI_CODE END IF
	1541	!OLI_CODE END DO
	1542	!OLI_CODE END DO ! i
	1543	!OLI_CODE END DO ! j
	1544	!OLI_CODE
	1545	!OLI_CODE DO n = 1, jpl
	1546	!OLI_CODE
	1547	!OLI_CODE IF (kcells(n) > 0) THEN
	1548	!OLI_CODE DO ij = 1, kcells(n)
	1549	!OLI_CODE i = indxii(ij,n)
	1550	!OLI_CODE j = indxjj(ij,n)
	1551	!OLI_CODE fwoc(i,j) = fwoc(i,j) + rhoic/rauw * zvuin(i,j,n) ! Completely refrozen lid goes into ocean (to be changed)
	1552	!OLI_CODE zvuin(i,j,n) = z0
	1553	!OLI_CODE END DO ! ij
	1554	!OLI_CODE END IF
	1555	!OLI_CODE
	1556	!OLI_CODE ! reload tracers
	1557	!OLI_CODE DO j = 1, jpj
	1558	!OLI_CODE DO i = 1, jpi
[7325]	1559	!OLI_CODE IF (zapondn(i,j,n) > epsi10) THEN
[7293]	1560	!OLI_CODE h_il(i,j,n) = zvuin(i,j,n) / zapondn(i,j,n)
	1561	!OLI_CODE ELSE
	1562	!OLI_CODE zvuin(i,j,n) = z0
	1563	!OLI_CODE h_il(i,j,n) = z0
	1564	!OLI_CODE END IF
[7325]	1565	!OLI_CODE IF (aicen(i,j,n) > epsi10) THEN
[7293]	1566	!OLI_CODE a_ip_frac(i,j,n) = zapondn(i,j,n) / aicen(i,j,n) * &
	1567	!OLI_CODE (1.0_wp - MAX(z0, SIGN(1.0_wp, -zvolpn(i,j,n))))
	1568	!OLI_CODE h_ip(i,j,n) = zhpondn(i,j,n)
	1569	!OLI_CODE ELSE
	1570	!OLI_CODE a_ip_frac(i,j,n) = z0
	1571	!OLI_CODE h_ip(i,j,n) = z0
	1572	!OLI_CODE h_il(i,j,n) = z0
	1573	!OLI_CODE END IF
	1574	!OLI_CODE END DO ! i
	1575	!OLI_CODE END DO ! j
	1576	!OLI_CODE
	1577	!OLI_CODE END DO ! n
	1578	!OLI_CODE
	1579	!OLI_CODE END SUBROUTINE compute_mp_topo
	1580	!OLI_CODE
	1581	!OLI_CODE
	1582	!OLI_CODE SUBROUTINE pond_area(aice,vice,rhos, &
	1583	!OLI_CODE aicen, vicen, vsnon, ticen, &
	1584	!OLI_CODE salin, zvolpn, zvolp, &
	1585	!OLI_CODE zapondn,zhpondn,dvolp)
	1586	!OLI_CODE !!-------------------------------------------------------------------
	1587	!OLI_CODE !! * ROUTINE pond_area *
	1588	!OLI_CODE !!
	1589	!OLI_CODE !! ** Purpose : Compute melt pond area, depth and melting rates
	1590	!OLI_CODE !!------------------------------------------------------------------
	1591	!OLI_CODE REAL (wp), INTENT(IN) :: &
	1592	!OLI_CODE aice,vice
	1593	!OLI_CODE
	1594	!OLI_CODE REAL (wp), DIMENSION(jpl), INTENT(IN) :: &
	1595	!OLI_CODE aicen, vicen, vsnon, rhos
	1596	!OLI_CODE
	1597	!OLI_CODE REAL (wp), DIMENSION(nlay_i,jpl), INTENT(IN) :: &
	1598	!OLI_CODE ticen, salin
	1599	!OLI_CODE
	1600	!OLI_CODE REAL (wp), DIMENSION(jpl), INTENT(INOUT) :: &
	1601	!OLI_CODE zvolpn
	1602	!OLI_CODE
	1603	!OLI_CODE REAL (wp), INTENT(INOUT) :: &
	1604	!OLI_CODE zvolp, dvolp
	1605	!OLI_CODE
	1606	!OLI_CODE REAL (wp), DIMENSION(jpl), INTENT(OUT) :: &
	1607	!OLI_CODE zapondn, zhpondn
	1608	!OLI_CODE
	1609	!OLI_CODE INTEGER :: &
	1610	!OLI_CODE n, ns, &
	1611	!OLI_CODE m_index, &
	1612	!OLI_CODE permflag
	1613	!OLI_CODE
	1614	!OLI_CODE REAL (wp), DIMENSION(jpl) :: &
	1615	!OLI_CODE hicen, &
	1616	!OLI_CODE hsnon, &
	1617	!OLI_CODE asnon, &
	1618	!OLI_CODE alfan, &
	1619	!OLI_CODE betan, &
	1620	!OLI_CODE cum_max_vol, &
	1621	!OLI_CODE reduced_aicen
	1622	!OLI_CODE
	1623	!OLI_CODE REAL (wp), DIMENSION(0:jpl) :: &
	1624	!OLI_CODE cum_max_vol_tmp
	1625	!OLI_CODE
	1626	!OLI_CODE REAL (wp) :: &
	1627	!OLI_CODE hpond, &
	1628	!OLI_CODE drain, &
	1629	!OLI_CODE floe_weight, &
	1630	!OLI_CODE pressure_head, &
	1631	!OLI_CODE hsl_rel, &
	1632	!OLI_CODE deltah, &
	1633	!OLI_CODE perm, &
	1634	!OLI_CODE apond, &
	1635	!OLI_CODE msno
	1636	!OLI_CODE
	1637	!OLI_CODE REAL (wp), parameter :: &
	1638	!OLI_CODE viscosity = 1.79e-3_wp, & ! kinematic water viscosity in kg/m/s
	1639	!OLI_CODE z0 = 0.0_wp , &
	1640	!OLI_CODE c1 = 1.0_wp , &
	1641	!OLI_CODE p4 = 0.4_wp , &
	1642	!OLI_CODE p6 = 0.6_wp , &
[7325]	1643	!OLI_CODE epsi10 = 1.0e-11_wp
[7293]	1644	!OLI_CODE
	1645	!OLI_CODE !-----------\|
	1646	!OLI_CODE ! \|
	1647	!OLI_CODE ! \|-----------\|
	1648	!OLI_CODE !___________\|___________\|______________________________________sea-level
	1649	!OLI_CODE ! \| \|
	1650	!OLI_CODE ! \| \|---^--------\|
	1651	!OLI_CODE ! \| \| \| \|
	1652	!OLI_CODE ! \| \| \| \|-----------\| \|-------
	1653	!OLI_CODE ! \| \| \|alfan(n)\| \| \|
	1654	!OLI_CODE ! \| \| \| \| \|--------------\|
	1655	!OLI_CODE ! \| \| \| \| \| \|
	1656	!OLI_CODE !---------------------------v-------------------------------------------
	1657	!OLI_CODE ! \| \| ^ \| \| \|
	1658	!OLI_CODE ! \| \| \| \| \|--------------\|
	1659	!OLI_CODE ! \| \| \|betan(n)\| \| \|
	1660	!OLI_CODE ! \| \| \| \|-----------\| \|-------
	1661	!OLI_CODE ! \| \| \| \|
	1662	!OLI_CODE ! \| \|---v------- \|
	1663	!OLI_CODE ! \| \|
	1664	!OLI_CODE ! \|-----------\|
	1665	!OLI_CODE ! \|
	1666	!OLI_CODE !-----------\|
	1667	!OLI_CODE
	1668	!OLI_CODE !-------------------------------------------------------------------
	1669	!OLI_CODE ! initialize
	1670	!OLI_CODE !-------------------------------------------------------------------
	1671	!OLI_CODE
	1672	!OLI_CODE DO n = 1, jpl
	1673	!OLI_CODE
	1674	!OLI_CODE zapondn(n) = z0
	1675	!OLI_CODE zhpondn(n) = z0
	1676	!OLI_CODE
[7325]	1677	!OLI_CODE IF (aicen(n) < epsi10) THEN
[7293]	1678	!OLI_CODE hicen(n) = z0
	1679	!OLI_CODE hsnon(n) = z0
	1680	!OLI_CODE reduced_aicen(n) = z0
	1681	!OLI_CODE ELSE
	1682	!OLI_CODE hicen(n) = vicen(n) / aicen(n)
	1683	!OLI_CODE hsnon(n) = vsnon(n) / aicen(n)
	1684	!OLI_CODE reduced_aicen(n) = c1 ! n=jpl
	1685	!OLI_CODE IF (n < jpl) reduced_aicen(n) = aicen(n) &
	1686	!OLI_CODE * (-0.024_wp*hicen(n) + 0.832_wp)
	1687	!OLI_CODE asnon(n) = reduced_aicen(n)
	1688	!OLI_CODE END IF
	1689	!OLI_CODE
	1690	!OLI_CODE ! This choice for alfa and beta ignores hydrostatic equilibium of categories.
	1691	!OLI_CODE ! Hydrostatic equilibium of the entire ITD is accounted for below, assuming
	1692	!OLI_CODE ! a surface topography implied by alfa=0.6 and beta=0.4, and rigidity across all
	1693	!OLI_CODE ! categories. alfa and beta partition the ITD - they are areas not thicknesses!
	1694	!OLI_CODE ! Multiplying by hicen, alfan and betan (below) are thus volumes per unit area.
	1695	!OLI_CODE ! Here, alfa = 60% of the ice area (and since hice is constant in a category,
	1696	!OLI_CODE ! alfan = 60% of the ice volume) in each category lies above the reference line,
	1697	!OLI_CODE ! and 40% below. Note: p6 is an arbitrary choice, but alfa+beta=1 is required.
	1698	!OLI_CODE
	1699	!OLI_CODE alfan(n) = p6 * hicen(n)
	1700	!OLI_CODE betan(n) = p4 * hicen(n)
	1701	!OLI_CODE
	1702	!OLI_CODE cum_max_vol(n) = z0
	1703	!OLI_CODE cum_max_vol_tmp(n) = z0
	1704	!OLI_CODE
	1705	!OLI_CODE END DO ! jpl
	1706	!OLI_CODE
	1707	!OLI_CODE cum_max_vol_tmp(0) = z0
	1708	!OLI_CODE drain = z0
	1709	!OLI_CODE dvolp = z0
	1710	!OLI_CODE
	1711	!OLI_CODE !--------------------------------------------------------------------------
	1712	!OLI_CODE ! the maximum amount of water that can be contained up to each ice category
	1713	!OLI_CODE !--------------------------------------------------------------------------
	1714	!OLI_CODE
	1715	!OLI_CODE DO n = 1, jpl-1 ! last category can not hold any volume
	1716	!OLI_CODE
	1717	!OLI_CODE IF (alfan(n+1) >= alfan(n) .and. alfan(n+1) > z0) THEN
	1718	!OLI_CODE
	1719	!OLI_CODE ! total volume in level including snow
	1720	!OLI_CODE cum_max_vol_tmp(n) = cum_max_vol_tmp(n-1) + &
	1721	!OLI_CODE (alfan(n+1) - alfan(n)) * sum(reduced_aicen(1:n))
	1722	!OLI_CODE
	1723	!OLI_CODE
	1724	!OLI_CODE ! subtract snow solid volumes from lower categories in current level
	1725	!OLI_CODE DO ns = 1, n
	1726	!OLI_CODE cum_max_vol_tmp(n) = cum_max_vol_tmp(n) &
	1727	!OLI_CODE - rhos(ns)/rauw * & ! fraction of snow that is occupied by solid ??rauw
	1728	!OLI_CODE asnon(ns) * & ! area of snow from that category
	1729	!OLI_CODE max(min(hsnon(ns)+alfan(ns)-alfan(n), alfan(n+1)- &
	1730	!OLI_CODE alfan(n)), z0)
	1731	!OLI_CODE ! thickness of snow from ns layer in n layer
	1732	!OLI_CODE END DO
	1733	!OLI_CODE
	1734	!OLI_CODE ELSE ! assume higher categories unoccupied
	1735	!OLI_CODE cum_max_vol_tmp(n) = cum_max_vol_tmp(n-1)
	1736	!OLI_CODE END IF
	1737	!OLI_CODE !IF (cum_max_vol_tmp(n) < z0) THEN
	1738	!OLI_CODE ! call abort_ice('negative melt pond volume')
	1739	!OLI_CODE !END IF
	1740	!OLI_CODE END DO
	1741	!OLI_CODE cum_max_vol_tmp(jpl) = cum_max_vol_tmp(jpl-1) ! last category holds no volume
	1742	!OLI_CODE cum_max_vol (1:jpl) = cum_max_vol_tmp(1:jpl)
	1743	!OLI_CODE
	1744	!OLI_CODE !----------------------------------------------------------------
	1745	!OLI_CODE ! is there more meltwater than can be held in the floe?
	1746	!OLI_CODE !----------------------------------------------------------------
	1747	!OLI_CODE IF (zvolp >= cum_max_vol(jpl)) THEN
[7325]	1748	!OLI_CODE drain = zvolp - cum_max_vol(jpl) + epsi10
[7293]	1749	!OLI_CODE zvolp = zvolp - drain
	1750	!OLI_CODE dvolp = drain
[7325]	1751	!OLI_CODE IF (zvolp < epsi10) THEN
[7293]	1752	!OLI_CODE dvolp = dvolp + zvolp
	1753	!OLI_CODE zvolp = z0
	1754	!OLI_CODE END IF
	1755	!OLI_CODE END IF
	1756	!OLI_CODE
	1757	!OLI_CODE ! height and area corresponding to the remaining volume
	1758	!OLI_CODE
	1759	!OLI_CODE call calc_hpond(reduced_aicen, asnon, hsnon, rhos, alfan, &
	1760	!OLI_CODE zvolp, cum_max_vol, hpond, m_index)
	1761	!OLI_CODE
	1762	!OLI_CODE DO n=1, m_index
	1763	!OLI_CODE zhpondn(n) = hpond - alfan(n) + alfan(1)
	1764	!OLI_CODE zapondn(n) = reduced_aicen(n)
	1765	!OLI_CODE END DO
	1766	!OLI_CODE apond = sum(zapondn(1:m_index))
	1767	!OLI_CODE
	1768	!OLI_CODE !------------------------------------------------------------------------
	1769	!OLI_CODE ! drainage due to ice permeability - Darcy's law
	1770	!OLI_CODE !------------------------------------------------------------------------
	1771	!OLI_CODE
	1772	!OLI_CODE ! sea water level
	1773	!OLI_CODE msno = z0
	1774	!OLI_CODE DO n=1,jpl
	1775	!OLI_CODE msno = msno + vsnon(n) * rhos(n)
	1776	!OLI_CODE END DO
	1777	!OLI_CODE floe_weight = (msno + rhoicvice + rau0zvolp) / aice
	1778	!OLI_CODE hsl_rel = floe_weight / rau0 &
	1779	!OLI_CODE - ((sum(betan(:)*aicen(:))/aice) + alfan(1))
	1780	!OLI_CODE
	1781	!OLI_CODE deltah = hpond - hsl_rel
	1782	!OLI_CODE pressure_head = grav * rau0 * max(deltah, z0)
	1783	!OLI_CODE
	1784	!OLI_CODE ! drain IF ice is permeable
	1785	!OLI_CODE permflag = 0
	1786	!OLI_CODE IF (pressure_head > z0) THEN
	1787	!OLI_CODE DO n = 1, jpl-1
	1788	!OLI_CODE IF (hicen(n) /= z0) THEN
	1789	!OLI_CODE CALL permeability_phi(ticen(:,n), salin(:,n), vicen(n), perm)
	1790	!OLI_CODE IF (perm > z0) permflag = 1
	1791	!OLI_CODE drain = permzapondn(n)pressure_head*rdt_ice / &
	1792	!OLI_CODE (viscosity*hicen(n))
	1793	!OLI_CODE dvolp = dvolp + min(drain, zvolp)
	1794	!OLI_CODE zvolp = max(zvolp - drain, z0)
[7325]	1795	!OLI_CODE IF (zvolp < epsi10) THEN
[7293]	1796	!OLI_CODE dvolp = dvolp + zvolp
	1797	!OLI_CODE zvolp = z0
	1798	!OLI_CODE END IF
	1799	!OLI_CODE END IF
	1800	!OLI_CODE END DO
	1801	!OLI_CODE
	1802	!OLI_CODE ! adjust melt pond DIMENSIONs
	1803	!OLI_CODE IF (permflag > 0) THEN
	1804	!OLI_CODE ! recompute pond depth
	1805	!OLI_CODE CALL calc_hpond(reduced_aicen, asnon, hsnon, rhos, alfan, &
	1806	!OLI_CODE zvolp, cum_max_vol, hpond, m_index)
	1807	!OLI_CODE DO n=1, m_index
	1808	!OLI_CODE zhpondn(n) = hpond - alfan(n) + alfan(1)
	1809	!OLI_CODE zapondn(n) = reduced_aicen(n)
	1810	!OLI_CODE END DO
	1811	!OLI_CODE apond = sum(zapondn(1:m_index))
	1812	!OLI_CODE END IF
	1813	!OLI_CODE END IF ! pressure_head
	1814	!OLI_CODE
	1815	!OLI_CODE !------------------------------------------------------------------------
	1816	!OLI_CODE ! total melt pond volume in category DOes not include snow volume
	1817	!OLI_CODE ! snow in melt ponds is not melted
	1818	!OLI_CODE !------------------------------------------------------------------------
	1819	!OLI_CODE
	1820	!OLI_CODE ! Calculate pond volume for lower categories
	1821	!OLI_CODE DO n=1,m_index-1
	1822	!OLI_CODE zvolpn(n) = zapondn(n) * zhpondn(n) &
	1823	!OLI_CODE - (rhos(n)/rauw) * asnon(n) * min(hsnon(n), zhpondn(n))!
	1824	!OLI_CODE END DO
	1825	!OLI_CODE
	1826	!OLI_CODE ! Calculate pond volume for highest category = remaining pond volume
	1827	!OLI_CODE IF (m_index == 1) zvolpn(m_index) = zvolp
	1828	!OLI_CODE IF (m_index > 1) THEN
	1829	!OLI_CODE IF (zvolp > sum(zvolpn(1:m_index-1))) THEN
	1830	!OLI_CODE zvolpn(m_index) = zvolp - sum(zvolpn(1:m_index-1))
	1831	!OLI_CODE ELSE
	1832	!OLI_CODE zvolpn(m_index) = z0
	1833	!OLI_CODE zhpondn(m_index) = z0
	1834	!OLI_CODE zapondn(m_index) = z0
	1835	!OLI_CODE ! If remaining pond volume is negative reduce pond volume of
	1836	!OLI_CODE ! lower category
[7325]	1837	!OLI_CODE IF (zvolp+epsi10 < sum(zvolpn(1:m_index-1))) &
[7293]	1838	!OLI_CODE zvolpn(m_index-1) = zvolpn(m_index-1)-sum(zvolpn(1:m_index-1))&
	1839	!OLI_CODE + zvolp
	1840	!OLI_CODE END IF
	1841	!OLI_CODE END IF
	1842	!OLI_CODE
	1843	!OLI_CODE DO n=1,m_index
[7325]	1844	!OLI_CODE IF (zapondn(n) > epsi10) THEN
[7293]	1845	!OLI_CODE zhpondn(n) = zvolpn(n) / zapondn(n)
	1846	!OLI_CODE ELSE
	1847	!OLI_CODE dvolp = dvolp + zvolpn(n)
	1848	!OLI_CODE zhpondn(n) = z0
	1849	!OLI_CODE zvolpn(n) = z0
	1850	!OLI_CODE zapondn(n) = z0
	1851	!OLI_CODE end IF
	1852	!OLI_CODE END DO
	1853	!OLI_CODE DO n = m_index+1, jpl
	1854	!OLI_CODE zhpondn(n) = z0
	1855	!OLI_CODE zapondn(n) = z0
	1856	!OLI_CODE zvolpn (n) = z0
	1857	!OLI_CODE END DO
	1858	!OLI_CODE
	1859	!OLI_CODE END SUBROUTINE pond_area
	1860	!OLI_CODE
	1861	!OLI_CODE
	1862	!OLI_CODE SUBROUTINE calc_hpond(aicen, asnon, hsnon, rhos, alfan, &
	1863	!OLI_CODE zvolp, cum_max_vol, &
	1864	!OLI_CODE hpond, m_index)
	1865	!OLI_CODE !!-------------------------------------------------------------------
	1866	!OLI_CODE !! * ROUTINE calc_hpond *
	1867	!OLI_CODE !!
	1868	!OLI_CODE !! ** Purpose : Compute melt pond depth
	1869	!OLI_CODE !!-------------------------------------------------------------------
	1870	!OLI_CODE
	1871	!OLI_CODE REAL (wp), DIMENSION(jpl), INTENT(IN) :: &
	1872	!OLI_CODE aicen, &
	1873	!OLI_CODE asnon, &
	1874	!OLI_CODE hsnon, &
	1875	!OLI_CODE rhos, &
	1876	!OLI_CODE alfan, &
	1877	!OLI_CODE cum_max_vol
	1878	!OLI_CODE
	1879	!OLI_CODE REAL (wp), INTENT(IN) :: &
	1880	!OLI_CODE zvolp
	1881	!OLI_CODE
	1882	!OLI_CODE REAL (wp), INTENT(OUT) :: &
	1883	!OLI_CODE hpond
	1884	!OLI_CODE
	1885	!OLI_CODE INTEGER, INTENT(OUT) :: &
	1886	!OLI_CODE m_index
	1887	!OLI_CODE
	1888	!OLI_CODE INTEGER :: n, ns
	1889	!OLI_CODE
	1890	!OLI_CODE REAL (wp), DIMENSION(0:jpl+1) :: &
	1891	!OLI_CODE hitl, &
	1892	!OLI_CODE aicetl
	1893	!OLI_CODE
	1894	!OLI_CODE REAL (wp) :: &
	1895	!OLI_CODE rem_vol, &
	1896	!OLI_CODE area, &
	1897	!OLI_CODE vol, &
	1898	!OLI_CODE tmp, &
	1899	!OLI_CODE z0 = 0.0_wp, &
[7325]	1900	!OLI_CODE epsi10 = 1.0e-11_wp
[7293]	1901	!OLI_CODE
	1902	!OLI_CODE !----------------------------------------------------------------
	1903	!OLI_CODE ! hpond is zero if zvolp is zero - have we fully drained?
	1904	!OLI_CODE !----------------------------------------------------------------
	1905	!OLI_CODE
[7325]	1906	!OLI_CODE IF (zvolp < epsi10) THEN
[7293]	1907	!OLI_CODE hpond = z0
	1908	!OLI_CODE m_index = 0
	1909	!OLI_CODE ELSE
	1910	!OLI_CODE
	1911	!OLI_CODE !----------------------------------------------------------------
	1912	!OLI_CODE ! Calculate the category where water fills up to
	1913	!OLI_CODE !----------------------------------------------------------------
	1914	!OLI_CODE
	1915	!OLI_CODE !----------\|
	1916	!OLI_CODE ! \|
	1917	!OLI_CODE ! \|
	1918	!OLI_CODE ! \|----------\| -- --
	1919	!OLI_CODE !__________\|__________\|_________________________________________ ^
	1920	!OLI_CODE ! \| \| rem_vol ^ \| Semi-filled
	1921	!OLI_CODE ! \| \|----------\|-- -- -- - ---\|-- ---- -- -- --v layer
	1922	!OLI_CODE ! \| \| \| \|
	1923	!OLI_CODE ! \| \| \| \|hpond
	1924	!OLI_CODE ! \| \| \|----------\| \| \|-------
	1925	!OLI_CODE ! \| \| \| \| \| \|
	1926	!OLI_CODE ! \| \| \| \|---v-----\|
	1927	!OLI_CODE ! \| \| m_index \| \| \|
	1928	!OLI_CODE !-------------------------------------------------------------
	1929	!OLI_CODE
	1930	!OLI_CODE m_index = 0 ! 1:m_index categories have water in them
	1931	!OLI_CODE DO n = 1, jpl
	1932	!OLI_CODE IF (zvolp <= cum_max_vol(n)) THEN
	1933	!OLI_CODE m_index = n
	1934	!OLI_CODE IF (n == 1) THEN
	1935	!OLI_CODE rem_vol = zvolp
	1936	!OLI_CODE ELSE
	1937	!OLI_CODE rem_vol = zvolp - cum_max_vol(n-1)
	1938	!OLI_CODE END IF
	1939	!OLI_CODE exit ! to break out of the loop
	1940	!OLI_CODE END IF
	1941	!OLI_CODE END DO
	1942	!OLI_CODE m_index = min(jpl-1, m_index)
	1943	!OLI_CODE
	1944	!OLI_CODE !----------------------------------------------------------------
	1945	!OLI_CODE ! semi-filled layer may have m_index different snow in it
	1946	!OLI_CODE !----------------------------------------------------------------
	1947	!OLI_CODE
	1948	!OLI_CODE !----------------------------------------------------------- ^
	1949	!OLI_CODE ! \| alfan(m_index+1)
	1950	!OLI_CODE ! \|
	1951	!OLI_CODE !hitl(3)--> \|----------\| \|
	1952	!OLI_CODE !hitl(2)--> \|------------\| * * * * *\| \|
	1953	!OLI_CODE !hitl(1)--> \|----------\|* * * * * * \|* * * * * \| \|
	1954	!OLI_CODE !hitl(0)-->------------------------------------------------- \| ^
	1955	!OLI_CODE ! various snow from lower categories \| \|alfa(m_index)
	1956	!OLI_CODE
	1957	!OLI_CODE ! hitl - heights of the snow layers from thinner and current categories
	1958	!OLI_CODE ! aicetl - area of each snow depth in this layer
	1959	!OLI_CODE
	1960	!OLI_CODE hitl(:) = z0
	1961	!OLI_CODE aicetl(:) = z0
	1962	!OLI_CODE DO n = 1, m_index
	1963	!OLI_CODE hitl(n) = max(min(hsnon(n) + alfan(n) - alfan(m_index), &
	1964	!OLI_CODE alfan(m_index+1) - alfan(m_index)), z0)
	1965	!OLI_CODE aicetl(n) = asnon(n)
	1966	!OLI_CODE
	1967	!OLI_CODE aicetl(0) = aicetl(0) + (aicen(n) - asnon(n))
	1968	!OLI_CODE END DO
	1969	!OLI_CODE hitl(m_index+1) = alfan(m_index+1) - alfan(m_index)
	1970	!OLI_CODE aicetl(m_index+1) = z0
	1971	!OLI_CODE
	1972	!OLI_CODE !----------------------------------------------------------------
	1973	!OLI_CODE ! reorder array according to hitl
	1974	!OLI_CODE ! snow heights not necessarily in height order
	1975	!OLI_CODE !----------------------------------------------------------------
	1976	!OLI_CODE
	1977	!OLI_CODE DO ns = 1, m_index+1
	1978	!OLI_CODE DO n = 0, m_index - ns + 1
	1979	!OLI_CODE IF (hitl(n) > hitl(n+1)) THEN ! swap order
	1980	!OLI_CODE tmp = hitl(n)
	1981	!OLI_CODE hitl(n) = hitl(n+1)
	1982	!OLI_CODE hitl(n+1) = tmp
	1983	!OLI_CODE tmp = aicetl(n)
	1984	!OLI_CODE aicetl(n) = aicetl(n+1)
	1985	!OLI_CODE aicetl(n+1) = tmp
	1986	!OLI_CODE END IF
	1987	!OLI_CODE END DO
	1988	!OLI_CODE END DO
	1989	!OLI_CODE
	1990	!OLI_CODE !----------------------------------------------------------------
	1991	!OLI_CODE ! divide semi-filled layer into set of sublayers each vertically homogenous
	1992	!OLI_CODE !----------------------------------------------------------------
	1993	!OLI_CODE
	1994	!OLI_CODE !hitl(3)----------------------------------------------------------------
	1995	!OLI_CODE ! \| * * * * * * * *
	1996	!OLI_CODE ! \|* * * * * * * * *
	1997	!OLI_CODE !hitl(2)----------------------------------------------------------------
	1998	!OLI_CODE ! \| * * * * * * * * \| * * * * * * * *
	1999	!OLI_CODE ! \|* * * * * * * * * \|* * * * * * * * *
	2000	!OLI_CODE !hitl(1)----------------------------------------------------------------
	2001	!OLI_CODE ! \| * * * * * * * * \| * * * * * * * * \| * * * * * * * *
	2002	!OLI_CODE ! \|* * * * * * * * * \|* * * * * * * * * \|* * * * * * * * *
	2003	!OLI_CODE !hitl(0)----------------------------------------------------------------
	2004	!OLI_CODE ! aicetl(0) aicetl(1) aicetl(2) aicetl(3)
	2005	!OLI_CODE
	2006	!OLI_CODE ! move up over layers incrementing volume
	2007	!OLI_CODE DO n = 1, m_index+1
	2008	!OLI_CODE
	2009	!OLI_CODE area = sum(aicetl(:)) - & ! total area of sub-layer
	2010	!OLI_CODE (rhos(n)/rau0) * sum(aicetl(n:jpl+1)) ! area of sub-layer occupied by snow
	2011	!OLI_CODE
	2012	!OLI_CODE vol = (hitl(n) - hitl(n-1)) * area ! thickness of sub-layer times area
	2013	!OLI_CODE
	2014	!OLI_CODE IF (vol >= rem_vol) THEN ! have reached the sub-layer with the depth within
	2015	!OLI_CODE hpond = rem_vol / area + hitl(n-1) + alfan(m_index) - &
	2016	!OLI_CODE alfan(1)
	2017	!OLI_CODE exit
	2018	!OLI_CODE ELSE ! still in sub-layer below the sub-layer with the depth
	2019	!OLI_CODE rem_vol = rem_vol - vol
	2020	!OLI_CODE END IF
	2021	!OLI_CODE
	2022	!OLI_CODE END DO
	2023	!OLI_CODE
	2024	!OLI_CODE END IF
	2025	!OLI_CODE
	2026	!OLI_CODE END SUBROUTINE calc_hpond
	2027	!OLI_CODE
	2028	!OLI_CODE
	2029	!OLI_CODE SUBROUTINE permeability_phi(ticen, salin, vicen, perm)
	2030	!OLI_CODE !!-------------------------------------------------------------------
	2031	!OLI_CODE !! * ROUTINE permeability_phi *
	2032	!OLI_CODE !!
	2033	!OLI_CODE !! ** Purpose : Determine the liquid fraction of brine in the ice
	2034	!OLI_CODE !! and its permeability
	2035	!OLI_CODE !!-------------------------------------------------------------------
	2036	!OLI_CODE REAL (wp), DIMENSION(nlay_i), INTENT(IN) :: &
	2037	!OLI_CODE ticen, & ! energy of melting for each ice layer (J/m2)
	2038	!OLI_CODE salin
	2039	!OLI_CODE
	2040	!OLI_CODE REAL (wp), INTENT(IN) :: &
	2041	!OLI_CODE vicen ! ice volume
	2042	!OLI_CODE
	2043	!OLI_CODE REAL (wp), INTENT(OUT) :: &
	2044	!OLI_CODE perm ! permeability
	2045	!OLI_CODE
	2046	!OLI_CODE REAL (wp) :: &
	2047	!OLI_CODE Sbr ! brine salinity
	2048	!OLI_CODE
	2049	!OLI_CODE REAL (wp), DIMENSION(nlay_i) :: &
	2050	!OLI_CODE Tin, & ! ice temperature
	2051	!OLI_CODE phi ! liquid fraction
	2052	!OLI_CODE
	2053	!OLI_CODE INTEGER :: k
	2054	!OLI_CODE
	2055	!OLI_CODE REAL (wp) :: &
	2056	!OLI_CODE c2 = 2.0_wp
	2057	!OLI_CODE
	2058	!OLI_CODE !-----------------------------------------------------------------
	2059	!OLI_CODE ! Compute ice temperatures from enthalpies using quadratic formula
	2060	!OLI_CODE !-----------------------------------------------------------------
	2061	!OLI_CODE
	2062	!OLI_CODE DO k = 1,nlay_i
	2063	!OLI_CODE Tin(k) = ticen(k)
	2064	!OLI_CODE END DO
	2065	!OLI_CODE
	2066	!OLI_CODE !-----------------------------------------------------------------
	2067	!OLI_CODE ! brine salinity and liquid fraction
	2068	!OLI_CODE !-----------------------------------------------------------------
	2069	!OLI_CODE
	2070	!OLI_CODE IF (maxval(Tin-rtt) <= -c2) THEN
	2071	!OLI_CODE
	2072	!OLI_CODE DO k = 1,nlay_i
	2073	!OLI_CODE Sbr = - 1.2_wp &
	2074	!OLI_CODE -21.8_wp * (Tin(k)-rtt) &
	2075	!OLI_CODE - 0.919_wp * (Tin(k)-rtt)**2 &
	2076	!OLI_CODE - 0.01878_wp * (Tin(k)-rtt)**3
	2077	!OLI_CODE phi(k) = salin(k)/Sbr ! liquid fraction
	2078	!OLI_CODE END DO ! k
	2079	!OLI_CODE
	2080	!OLI_CODE ELSE
	2081	!OLI_CODE
	2082	!OLI_CODE DO k = 1,nlay_i
	2083	!OLI_CODE Sbr = -17.6_wp * (Tin(k)-rtt) &
	2084	!OLI_CODE - 0.389_wp * (Tin(k)-rtt)**2 &
	2085	!OLI_CODE - 0.00362_wp* (Tin(k)-rtt)**3
	2086	!OLI_CODE phi(k) = salin(k)/Sbr ! liquid fraction
	2087	!OLI_CODE END DO
	2088	!OLI_CODE
	2089	!OLI_CODE END IF
	2090	!OLI_CODE
	2091	!OLI_CODE !-----------------------------------------------------------------
	2092	!OLI_CODE ! permeability
	2093	!OLI_CODE !-----------------------------------------------------------------
	2094	!OLI_CODE
	2095	!OLI_CODE perm = 3.0e-08_wp * (minval(phi))**3
	2096	!OLI_CODE
	2097	!OLI_CODE END SUBROUTINE permeability_phi
	2098	!OLI_CODE
	2099	!OLI_CODE #else
	2100	!OLI_CODE !!----------------------------------------------------------------------
	2101	!OLI_CODE !! Default option Dummy Module No LIM-3 sea-ice model
	2102	!OLI_CODE !!----------------------------------------------------------------------
	2103	!OLI_CODE CONTAINS
	2104	!OLI_CODE SUBROUTINE lim_mp_init ! Empty routine
	2105	!OLI_CODE END SUBROUTINE lim_mp_init
	2106	!OLI_CODE SUBROUTINE lim_mp ! Empty routine
	2107	!OLI_CODE END SUBROUTINE lim_mp
	2108	!OLI_CODE SUBROUTINE compute_mp_topo ! Empty routine
	2109	!OLI_CODE END SUBROUTINE compute_mp_topo
	2110	!OLI_CODE SUBROUTINE pond_area ! Empty routine
	2111	!OLI_CODE END SUBROUTINE pond_area
	2112	!OLI_CODE SUBROUTINE calc_hpond ! Empty routine
	2113	!OLI_CODE END SUBROUTINE calc_hpond
	2114	!OLI_CODE SUBROUTINE permeability_phy ! Empty routine
	2115	!OLI_CODE END SUBROUTINE permeability_phy
	2116	!OLI_CODE #endif
	2117	!OLI_CODE !!======================================================================
	2118	!OLI_CODE END MODULE limmp_topo
	2119	!OLI_CODE
[7325]	2120	#else
	2121	!!----------------------------------------------------------------------
	2122	!! Default option Empty module NO LIM sea-ice model
	2123	!!----------------------------------------------------------------------
	2124	CONTAINS
	2125	SUBROUTINE lim_mp_init ! Empty routine
	2126	END SUBROUTINE lim_mp_init
	2127	SUBROUTINE lim_mp ! Empty routine
	2128	END SUBROUTINE lim_mp
	2129	SUBROUTINE lim_mp_topo ! Empty routine
	2130	END SUBROUTINE lim_mp_topo
[8060]	2131	SUBROUTINE lim_mp_cesm ! Empty routine
	2132	END SUBROUTINE lim_mp_cesm
[7325]	2133	SUBROUTINE lim_mp_area ! Empty routine
	2134	END SUBROUTINE lim_mp_area
	2135	SUBROUTINE lim_mp_perm ! Empty routine
	2136	END SUBROUTINE lim_mp_perm
	2137	#endif
	2138
	2139	!!======================================================================
	2140	END MODULE limmp

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