MITgcm/doc/diags_changes.txt

Jun 21, 2009
Some redundancies and relations for model diagnostics:

1) Qnet = QNETtave = - oceQnet = SIqnet
   for open-ocean: Qnet = EXFqnet = SIqneto

2) EXFqnet = EXFlwnet + EXFswnet - EXFhl - EXFhs

3) Qsw = QSWtave = - oceQsw = SIqsw
   for open-ocean: Qsw = EXFswnet

4) EmPmR = EmPmRtave = -oceFWflx = SIempmr

================================================================

Nov 19, 2006 (after tag checkpoint58r_post)

I) Some diagnostics have been renamed (essentially, to better
match the content):

1) name:        description (oceanic set-up):
PRESSURE        Cell-Center Height
replaced by:
RCENTER         Cell-Center Height

2) name:        description (oceanic set-up):
TICE            heat from melt/freeze of sea-ice, >0 increases theta
replaced by:
oceFreez        heating from freezing of sea-water (allowFreezing=T)

3) name:        description (oceanic set-up):
TAUX            zonal surface wind stress, >0 increases uVel
TAUY            meridional surf. wind stress, >0 increases vVel
replaced by:
oceTAUX         zonal surface wind stress, >0 increases uVel
oceTAUY         meridional surf. wind stress, >0 increases vVel

4) name:        description (oceanic set-up):
SWFLUX          net upward SW radiation, >0 increases theta
replaced by:
oceQsw          net Short-Wave radiation (+=down), >0 increases theta

5) name:        description (oceanic set-up):
DIFx_TH         Zonal      Diffusive Flux of Pot.Temperature
DIFy_TH         Meridional Diffusive Flux of Pot.Temperature
replaced by:
DFxE_TH         Zonal      Diffusive Flux of Pot.Temperature
DFyE_TH         Meridional Diffusive Flux of Pot.Temperature

6) name:        description (oceanic set-up):
DIFx_SLT        Zonal      Diffusive Flux of Salinity
DIFy_SLT        Meridional Diffusive Flux of Salinity
replaced by:
DFxE_SLT        Zonal      Diffusive Flux of Salinity
DFyE_SLT        Meridional Diffusive Flux of Salinity

-----------------------------------------------
II) Change description of existing diagnostics:

name:           old description (oceanic set-up):
TFLUX           net surface heat flux, >0 increases theta
SFLUX           net surface salt flux, >0 increases salt
name:           new description (oceanic set-up):
TFLUX           total heat flux (match heat-content variations), >0 increases theta
SFLUX           total salt flux (match salt-content variations), >0 increases salt

-----------------------------------------------
III) New diagnostics have been added:

name:           description (oceanic set-up):
atmPload        Atmospheric pressure loading
sIceLoad        sea-ice loading (in Mass of ice+snow / area unit)
oceQnet         net surface heat flux into the ocean (+=down), >0 increases theta
oceFWflx        net surface Fresh-Water flux into the ocean (+=down), >0 decreases salinity
oceSflux        net surface Salt flux into the ocean (+=down), >0 increases salinity
surForcT        model surface forcing for Temperature, >0 increases theta
surForcS        model surface forcing for Salinity, >0 increases salinity

--------------------------------------------------------------------------
Relation between surForcT,surForcS and others surface forcing diagnostics:
 [x] = average of model variable "x" over the diagnostic time interval

a) if useRealFreshWaterFlux=F or (nonlinFreeSurf=0 & usingZCoords=T)
 surForcT = oceQnet  + TRELAX - oceQsw
 surForcS = oceSflux + SRELAX - [PmEpR*So]
  (with So = local Sea-Surface Salinity (SSS) if convertFW2Salt=-1
    and So = convertFW2Salt otherwise)
 oceFWflx = [PmEpR]
 TFLUX = surForcT + oceQsw + oceFreez
 SFLUX = surForcS

b) if useRealFreshWaterFlux=T & (nonlinFreeSurf>0 or usingPCoords=T),
In general:
 surForcT = oceQnet  + TRELAX - oceQsw + [T_dilution_effect]*Cp
 surForcS = oceSflux + SRELAX          + [S_dilution_effect]
    where T_dilution_effect = PmEpR*( temp_EvPrRn - SST )
      and S_dilution_effect = PmEpR*( salt_EvPrRn - SSS )
 oceFWflx = [PmEpR]
 TFLUX = surForcT + oceQsw + oceFreez + [PmEpR*SST]*Cp
 SFLUX = surForcS + [PmEpR*SSS]

And with the default value: salt_EvPrRn=0. & temp_EvPrRn=UNSET_RL
 (=> no dilution effect on Temp.):
 surForcT = oceQnet  + TRELAX - oceQsw
 surForcS = oceSflux + SRELAX - [PmEpR*SSS]

Notes:
1) here PmEpR is assumed to be the fresh-water mass flux
 per surface area [units: kg/m^2/s] whereas the model variable
 EmPmR is still a volume flux per surface area [units: m/s].
2) with Linear Free surface (nonlinFreeSurf=0), the term
corresponding to w_surface*SST,SSS is missing in TFLUX,SFLUX
[might be added later ?] to match exactly the Heat and Salt
budget evolution.
--------------------------------------------------------------------------
1	dimitri	1.1	Jun 21, 2009
2			Some redundancies and relations for model diagnostics:
3
4			1) Qnet = QNETtave = - oceQnet = SIqnet
5			for open-ocean: Qnet = EXFqnet = SIqneto
6
7			2) EXFqnet = EXFlwnet + EXFswnet - EXFhl - EXFhs
8
9			3) Qsw = QSWtave = - oceQsw = SIqsw
10			for open-ocean: Qsw = EXFswnet
11
12			4) EmPmR = EmPmRtave = -oceFWflx = SIempmr
13
14			================================================================
15
16			Nov 19, 2006 (after tag checkpoint58r_post)
17
18			I) Some diagnostics have been renamed (essentially, to better
19			match the content):
20
21			1) name: description (oceanic set-up):
22			PRESSURE Cell-Center Height
23			replaced by:
24			RCENTER Cell-Center Height
25
26			2) name: description (oceanic set-up):
27			TICE heat from melt/freeze of sea-ice, >0 increases theta
28			replaced by:
29			oceFreez heating from freezing of sea-water (allowFreezing=T)
30
31			3) name: description (oceanic set-up):
32			TAUX zonal surface wind stress, >0 increases uVel
33			TAUY meridional surf. wind stress, >0 increases vVel
34			replaced by:
35			oceTAUX zonal surface wind stress, >0 increases uVel
36			oceTAUY meridional surf. wind stress, >0 increases vVel
37
38			4) name: description (oceanic set-up):
39			SWFLUX net upward SW radiation, >0 increases theta
40			replaced by:
41			oceQsw net Short-Wave radiation (+=down), >0 increases theta
42
43			5) name: description (oceanic set-up):
44			DIFx_TH Zonal Diffusive Flux of Pot.Temperature
45			DIFy_TH Meridional Diffusive Flux of Pot.Temperature
46			replaced by:
47			DFxE_TH Zonal Diffusive Flux of Pot.Temperature
48			DFyE_TH Meridional Diffusive Flux of Pot.Temperature
49
50			6) name: description (oceanic set-up):
51			DIFx_SLT Zonal Diffusive Flux of Salinity
52			DIFy_SLT Meridional Diffusive Flux of Salinity
53			replaced by:
54			DFxE_SLT Zonal Diffusive Flux of Salinity
55			DFyE_SLT Meridional Diffusive Flux of Salinity
56
57			-----------------------------------------------
58			II) Change description of existing diagnostics:
59
60			name: old description (oceanic set-up):
61			TFLUX net surface heat flux, >0 increases theta
62			SFLUX net surface salt flux, >0 increases salt
63			name: new description (oceanic set-up):
64			TFLUX total heat flux (match heat-content variations), >0 increases theta
65			SFLUX total salt flux (match salt-content variations), >0 increases salt
66
67			-----------------------------------------------
68			III) New diagnostics have been added:
69
70			name: description (oceanic set-up):
71			atmPload Atmospheric pressure loading
72			sIceLoad sea-ice loading (in Mass of ice+snow / area unit)
73			oceQnet net surface heat flux into the ocean (+=down), >0 increases theta
74			oceFWflx net surface Fresh-Water flux into the ocean (+=down), >0 decreases salinity
75			oceSflux net surface Salt flux into the ocean (+=down), >0 increases salinity
76			surForcT model surface forcing for Temperature, >0 increases theta
77			surForcS model surface forcing for Salinity, >0 increases salinity
78
79			--------------------------------------------------------------------------
80			Relation between surForcT,surForcS and others surface forcing diagnostics:
81			[x] = average of model variable "x" over the diagnostic time interval
82
83			a) if useRealFreshWaterFlux=F or (nonlinFreeSurf=0 & usingZCoords=T)
84			surForcT = oceQnet + TRELAX - oceQsw
85			surForcS = oceSflux + SRELAX - [PmEpR*So]
86			(with So = local Sea-Surface Salinity (SSS) if convertFW2Salt=-1
87			and So = convertFW2Salt otherwise)
88			oceFWflx = [PmEpR]
89			TFLUX = surForcT + oceQsw + oceFreez
90			SFLUX = surForcS
91
92			b) if useRealFreshWaterFlux=T & (nonlinFreeSurf>0 or usingPCoords=T),
93			In general:
94			surForcT = oceQnet + TRELAX - oceQsw + [T_dilution_effect]*Cp
95			surForcS = oceSflux + SRELAX + [S_dilution_effect]
96			where T_dilution_effect = PmEpR*( temp_EvPrRn - SST )
97			and S_dilution_effect = PmEpR*( salt_EvPrRn - SSS )
98			oceFWflx = [PmEpR]
99			TFLUX = surForcT + oceQsw + oceFreez + [PmEpRSST]Cp
100			SFLUX = surForcS + [PmEpR*SSS]
101
102			And with the default value: salt_EvPrRn=0. & temp_EvPrRn=UNSET_RL
103			(=> no dilution effect on Temp.):
104			surForcT = oceQnet + TRELAX - oceQsw
105			surForcS = oceSflux + SRELAX - [PmEpR*SSS]
106
107			Notes:
108			1) here PmEpR is assumed to be the fresh-water mass flux
109			per surface area [units: kg/m^2/s] whereas the model variable
110			EmPmR is still a volume flux per surface area [units: m/s].
111			2) with Linear Free surface (nonlinFreeSurf=0), the term
112			corresponding to w_surface*SST,SSS is missing in TFLUX,SFLUX
113			[might be added later ?] to match exactly the Heat and Salt
114			budget evolution.
115			--------------------------------------------------------------------------