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faaf90f2c5 Jean* ================================================================
                 Apr 03, 2010
                 1) add diagnostics for KPP non-local flux of Temp, Salt and pTracers
                  (respectively: KPPg_TH, KPPg_SLT and KPPgTrXX for tracer number XX)
                 This allows to close the tracer budget when using KPP.
                 
                 2) Change the diagnostic for KPP non-local term:
                  name:          description:
                 KPPghat         Nonlocal transport coefficient (s/m^2)
                                 (correspond to KPP ghat field, from which the non-local
                                 flux of tracer (T,S,pTr) is computed, as the product of
                                 ghat , KPPdiffKz and surface flux.)
                 replaced by:
                 KPPghatK        ratio of KPP non-local (salt) flux relative to surface-flux
                                 (correspond to the product: KPP_ghat * KPPdiffKzS
                                  which gives the fraction of the the surface flux of Salt
                                  that KPP return as non local flux; also valid for any passive
                                  tracer, but could be different for Temp., see comment below)
                 
                 comments (from mitgcm-devel list):
                  I was also tempted to replace the KPPghat diagnostics
                  with something more useful which incorporates the KPPdiffKz:
                  Since it is the product KPPghat*KPPdiffKz which matters,
                  and given that short time variations of both (which have no
                  reason not to be correlated) can be significant,
                  the product of the 2 time-ave is very likely to be quiet
                  far from the time-ave of the product.
                  It has also the advantage of a simpler interpretation:
                  the product is just the fraction of the surface flux which is
                  treated as non local (no unit, instead of this funny s/m^2
                  for KPPghat).
                 
                  Then I would propose to just pick one KPPdiffKz (for instance,
                  KPPdiffKzS for salinity, since it's also used for Ptracers),
                  and have only 1 diag: "KPPghatK" for KPPghat*KPPdiffKzS (no unit).
                 
                  For temperature (KPPghat*KPPdiffKzT), it's probably not too different
                  from the one computed for salinity (might be in fact a better
                  time-ave value that what we have now, for the reason above).
                  And to get a precise diagnostic of KPP-non-local effect
                  on temperature, there would be this new diagnostic directly from
                  kpp_transport_t.F (which can be used to close a Temp. budget).
                 
                 ================================================================
14ff2fe9e4 Dimi* Jun 21, 2009
                 Some redundancies and relations for model diagnostics:
                 
                 1) Qnet = QNETtave = - oceQnet = SIqnet
                 
54ac884ead Dimi* 2) For open-ocean, i.e., when there is no sea ice:
                    Qnet = QNETtave = - oceQnet = SIqnet = EXFqnet = SIqneto = SIatmQnt
14ff2fe9e4 Dimi* 
54ac884ead Dimi* 3) EXFqnet = EXFlwnet + EXFswnet - EXFhl - EXFhs
14ff2fe9e4 Dimi* 
54ac884ead Dimi* 4) Qsw = QSWtave = - oceQsw = SIqsw
                 
                 5) For open-ocean, i.e., when there is no sea ice:
                    Qsw = QSWtave = - oceQsw = SIqsw = EXFswnet
                 
                 6) EmPmR = EmPmRtave = -oceFWflx = SIempmr
14ff2fe9e4 Dimi* 
                 ================================================================
                 
                 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:
d9ed7f50c5 Dimi* 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 FreeSurf, there is a small loss of heat/salt/tracer at the
                    surface (d/dt(Eta) inconsistent with fixed surf grid cell thickness:
                    a) if linFSConserveTr is set to true (file "data"), then the model 
                       corrects for this (see S/R calc_wsurf_tr.F).
                    b) if linFSConserveTr=False (=the default), the term corresponding
                       to w_surface*SST,SSS is missing in TFLUX,SFLUX to match exactly the
                       Heat and Salt budget evolution so need to account for this term in
                       the budget, which can be obtained from the 1rst level
                       of WTHMASS / WSLTMASS diagnostics (diagnostics ADVr_TH / ADVr_SLT
                       is not the right one for this purpose, it's just zero at k=1).
                 3) There is just one more undocumented/hidden case
                    (nonlinFreeSurf=0 & select_rStar=-1) which is not covered.
3fd0679845 Patr* 4) For extended diagnostics in the presence of sea-ice and using
                    pkg/seaice/ (in particular atmosphere-ice and ice-ocean fluxes)
                    see online documentation, section 6.6.2.6 "SEAICE diagnostics"
                 

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