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	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	--------------------------------------------------------------------------