IJVAR4X3.TXT     Definition of IxJ Climate Variables     2008/03/25

Snow and Ice Cover
------------------
SIC:   Horizontal Sea Ice Cover (%) over ocean or lake
       = AIJ(1)*100 / FWATER*IDACC(1)
SNCSI: SNow Cover (%) over Sea Ice or lake ice
       = AIJ(2)*100 / AIJ(1)
SNCGI: SNow Cover (%) over Glacial Ice
       = AIJ(3)*100 / FGICE*IDACC(1)
SNCG:  SNow Cover (%) over Ground
       = AIJ(4)*100 / FGRND*IDACC(1)

SNOWC: Composite SNOW Cover (%)
       = SNCSI*FWATER + SNCGI*FGICE + SNCG*FGRND
       = [AIJ(2) + AIJ(3) + AIJ(4)]*100 / IDACC(1)
ISNC   Composite Ice or SNow Cover (%)
       = {[AIJ(1) + AIJ(4)]/IDACC(1) + FGICE}*100

Clouds
------
CLDL:  Low CLouD cover (%) or percentage of time that the cloud top
       pressure is greater than 680 mb when the vertically integrated
       cloud optical depth is at least .75; low clouds may not be
       detected if there are higher clouds present
       = AIJ(6)*100 / IDACC(2)
CLDM:  Middle CLouD cover (%) or percentage of time that the cloud top
       pressure is between 440 and 680 mb when the vertically
       integrated cloud optical depth is at least .75; middle clouds
       may not be detected if there are higher clouds present
       = AIJ(7)*100 / IDACC(2)
CLDH:  High CLouD cover (%) or percentage of time that the cloud top
       pressure is less than 440 mb when the vertically integrated
       cloud optical depth is at least .75
       = AIJ(8)*100 / IDACC(2)
CLDOD: Vertically integrated CLouD Optical Depth
       = AIJ(9) / IDACC(2)

CLDT:  Total CLouD cover (%) or percentage of time that the vertically
       integrated cloud optical depth is at least .75
       = CLDL + CLDM + CLDH = [AIJ(6) + AIJ(7) + AIJ(8)]*100 / IDACC(2)

Evaporation and Precipitation
-----------------------------
EVAPOO:EVAPoration minus dew (mm/day) over Open Ocean or open lake
       = -AIJ(11)*NDAY / [FWATER*IDACC(1)-AIJ(1)]
EVAPSI:EVAPoration minus dew (mm/day) over Sea Ice or lake Ice
       = -AIJ(12)*NDAY / AIJ(1)
EVAPGI:EVAPoration minus dew (mm/day) over Glacial Ice
       = -AIJ(13)*NDAY / IDACC(1)
EVAPGR:EVAPoration minus dew (mm/day) over snow-free GRound
       = -AIJ(14)*NDAY / [FGRND*IDACC(1)-AIJ(4)]
EVAPGS:EVAPoration minus dew (mm/day) over Snow-covered Ground
       = -AIJ(15)*NDAY / AIJ(4)
EVAPR: EVAPoration (mm/day) from Roots (layers 2 through 4 of Ground)
       = -AIJ(16)*NDAY / FGRND*IDACC(1)
WETGR: Surface WETness (%) over snow-free ground;
       = AIJ(17)*100 / NSURF*[FGRND*IDACC(1)-AIJ(4)]


EVAP:  Composite EVAPoration minus dew (mm/day)
       = [EVAPOO*FWATER*(1-SIC) + EVAPSI*FWATER*SIC + EVAPGI*FGICE +
          + EVAPGR*FGRND*(1-SNCG) + EVAPGS*FGRND*SNGC]
       = -[AIJ(11)+AIJ(12)+AIJ(13)*FGICE+AIJ(14)+AIJ(15)]*NDAY/IDACC(1)

PREC:  PRECipitation (mm/day)
       = AIJ(18)*NDAY / IDACC(1)
PRECNV:CoNVective PREcipitation (mm/day)
       = AIJ(19)*NDAY / IDACC(1)

SNOWF: SNOW Fall (mm/day)
       = -AIJ(36)*NDAY / ELHM*IDACC(1), limited by 0 and PREC

Mass
----
MSI:   Ice Mass (kg/m²) over Sea Ice or lake ice
       = AIJ(21) / AIJ(1)
MSNSI: SNow Mass (kg/m²) over Sea Ice or lake ice
       = AIJ(22) / AIJ(2)
MSNGI: SNow Mass (kg/m²) over Glacial Ice
       = AIJ(23) / IDACC(1)
MSNG:  SNow Mass (kg/m²) over Ground
       = AIJ(24) / FGRND*IDACC(1)
MISG:  Surface Ice (kg/m²) over Ground
       = AIJ(25) / FGRND*IDACC(1)
MSWG:  Soil Water Mass (kg/m²) over Ground
       = AIJ(26) / FGRND*IDACC(1)
MIGI:  Mass of Glacial Ice (kg/year*m²) sent to (minus recovered from)
       the Infinite Ice reservoir
       = AIJ(27)*FGICE*NDAY*EDAYzY / IDACC(1)
MICBM: Ice Calving and Ice Berg Melting (kg/m²)
       = AIJ(28) / IDACC(1)
MLLAK: Liquid LAKe and river Mass (kg/m²)
       = AIJ(29) / IDACC(1)
MRVR:  RiVeR Mass (10^6 kg/s) leaving each continental grid cell
       = AIJ(30) / DTS*IDACC(1)*10^6

MSNOW: Composite SNOW Mass (kg/m²)
       = [AIJ(22) + AIJ(23)*FGICE + AIJ(24)] / IDACC(1)
MWC:   Composite Water Mass (kg/m²) over Continents
       = [AIJ(21) + AIJ(23)*FGICE + AIJ(24) + AIJ(25) + AIJ(26) +
          + AIJ(29)] / (1-FOCEAN)*IDACC(1)
MWG:   Composite Water Mass (kg/m²) over Ground
       = [AIJ(24) + AIJ(25) + AIJ(26)] / FGRND*IDACC(1)
MSIC:  Converged Sea Ice Mass (kg/day*m²)
       = [AIJ(I-1,83)-AIJ(I,83) + AIJ(J-1,88)-AIJ(J,88)]*NDAY /
         / DXYP*IDACC(1)

MA:    Air Mass (kg/m²)
       = vertical sum of AIJL(1) / IDACC(4)
MWV:   Water Vapor Mass (kg/m²)
       = vertical sum of AIJL(9) / DXYP*IDACC(4)
MO:    Ocean Mass (10³ kg/m²)
       = vertical sum of OIJL(1) / 1000*IDACC(5)
MOSI:  Ocean Mass plus Sea Ice Mass (10³ kg/m²)
       = [vertical sum of OIJL(1)/IDACC(5) + AIJ(21)/IDACC(1)] / 1000
MSALT: Ocean SALT (10³ kg/m²)
       = vertical sum of OIJL(9) / 1000*DXYP*IDACC(5)


Heat Fluxes
-----------
HSOO:  Net Heat flux into Surface - HPRE (W/m²) over Open water
       = AIJ(31) / DTS*[FWATER*IDACC(1)-AIJ(1)]
HSSI:  Net Heat flux into Surface - HPRE (W/m²) over Sea Ice
       = AIJ(32) / DTS*AIJ(1)
HSGI:  Net Heat flux into Surface - HPRE (W/m²) over Glacial Ice
       = AIJ(33) / DTS*IDACC(1)
HSGR:  Net Heat flux into Surface - HPRE (W/m²) over snow-free GRound
       = AIJ(34) / DTS*[FGRND*IDACC(1)-AIJ(4)]
HSGS:  Net Heat flux into Surface - HPRE (W/m²) over Snow-covered Ground
       = AIJ(35) / DTS*AIJ(4)
HPRE:  Energy of PREcipitation (W/m²); includes sensible heat of
       condensate (referenced from 0°C) minus latent energy of snow
       = AIJ(36) / DTS*IDACC(1)
HIGI:  Glacial Ice Energy (W/m²) sent to (minus recovered from) the
       Infinite Ice reservoir
       = AIJ(37)*FGICE / DTS*IDACC(1)
HSEN:  Conductive SENsible Heat flux (W/m²) from surface to atmosphere
       = -AIJ(38) / DTS*IDACC(1)
HWV:   Water Vapor Heat flux (W/m²) from surface to atmosphere;
       includes sensible  and latent heat of water vapor
       = -AIJ(39) / DTS*IDACC(1)
HRVR:  RiVeR energy (10^10 W) leaving each continental grid cell
       = AIJ(40) / DTS*IDACC(1)*10^10

HS:    Net Heat flux from Surface (W/m²)
       = RSSA - RTSE - HSEN - HWV + HPRE
       = [AIJ(31) + AIJ(32) + AIJ(33)*FGICE + AIJ(34) + AIJ(35) +
          + AIJ(36)] / DTS*IDACC(1)
HOCT:  Converged Ocean Heat Transport (W/m²)
       = vertical sum of [OIJL(I-1,6)-OIJL(I,6) + OIJL(J-1,7)+OIJL(J,7)]
         / DTS*IDACC(1)*DXYP

Radiation
---------
RSPI:  Solar Radiation Incident on Planet (W/m²)
       = AIJ(41) / IDACC(1)
RSAA:  Solar Radiation Absorbed by Atmosphere (W/m²)
       = AIJ(42) / IDACC(1)
RSSI:  Solar Radiation Incident on Surface (W/m²)
       = AIJ(43) / IDACC(1)
RSSA:  Solar Radiation Absorbed by Surface (W/m²)
       = AIJ(44) / IDACC(1)*DTS

RSSR:  Solar Radiation Reflected from Surface (W/m²)
       = [AIJ(43) - AIJ(44)/DTS] / IDACC(1)
RSPA:  Solar Radiation Absorbed by Planet (W/m²)
       = [AIJ(42) + AIJ(44)/DTS] / IDACC(1)
RSPR:  Solar Radiation Reflected by Planet (W/m²)
       = [AIJ(41) - AIJ(42) - AIJ(44)/DTS] / IDACC(1)
ALBP:  Planetary ALBedo (%)
       = 100*(1 - RSPA/RSPI) = 100*{1 - [AIJ(42)+AIJ(44)/DTS]/AIJ(41)}
ALBS:  Surface ALBedo (%)
       = 100*(1 - RSSA/RSSI) = 100*[1 - AIJ(44)/DTS*AIJ(43)]

RTAE:  Thermal Radiation Emitted by Atmosphere (W/m²)
       = -AIJ(46) / IDACC(1)
RTSD:  Thermal Radiation Downward onto Surface (W/m²)
       = AIJ(47) / IDACC(1)
RTSE:  Net Thermal Radiation Emitted by Surface (W/m²)
       = -AIJ(48) / DTS*IDACC(1)

RTSU:  Thermal Radiation Upward from Surface (W/m²)
       = [AIJ(47) - AIJ(48)/DTS] / IDACC(1)
RTPE:  Thermal Radiation Emitted by Planet (W/m²)
       = -[AIJ(46) + AIJ(48)/DTS] / IDACC(1)

Temperature
-----------
TGOO:  Upper surface Temperature (°C) over Open Ocean or open lake
       = AIJ(51) / NSURF*[FWATER*IDACC(1)-AIJ(1)]
TGSI:  Ground Temperature (°C) over Sea Ice or lake ice
       = AIJ(52) / NSURF*AIJ(1)
TGGI:  Ground Temperature (°C) over Glacial Ice
       = AIJ(53) / NSURF*IDACC(1)
TGGR:  Ground Temperature (°C) over snow-free GRound
       = AIJ(54) / NSURF*[FGRND*IDACC(1)-AIJ(4)]
TGGS:  Ground Temperature (°C) over Snow-covered Ground
       = AIJ(55) / NSURF*AIJ(4)
TAS:   Surface Air Temperature (°C)
       = AIJ(56) / NSURF*IDACC(1)
TGMIN: Daily MINimum Ground Temperature (°C)
       = AIJ(57) / IDACC(12)
TGMAX: Daily MAXimum Ground Temperature (°C)
       = AIJ(58) / IDACC(12)
TSMIN: Daily MINimum near Surface air Temperature (°C)
       = AIJ(59) / IDACC(12)
TSMAX: Daily MAXimum near Surface air Temperature (°C)
       = AIJ(60) / IDACC(12)

TG:    Composite Ground Temperature (°C)
       = [AIJ(51)+AIJ(52)+AIJ(53)*FGICE+AIJ(54)+AIJ(55)] /
         / NSURF*IDACC(1)
TS:    Near Surface air Temperature (°C)
       = .5*TAS + .5*TG
       = .5*[AIJ(51)+AIJ(52)+AIJ(53)*FGICE+AIJ(54)+AIJ(55) + AIJ(56)] /
         / NSURF*IDACC(1)
TGRD:  Daily Range of Ground Temperature (°C)
       = TGMAX - TGMIN = [AIJ(58) - AIJ(57)] / IDACC(12)
TSRD:  Daily Range of near Surface air Temperature (°C)
       = TSMAX - TSMIN = [AIJ(60) - AIJ(59)] / IDACC(12)
TRVR:  Temperature of RiVeR outflow (°C)
       = [AIJ(40) - AIJ(30)*GRAV*ZATMO] / AIJ(30)*SHCW

TG1:   Temperature of layer 1 (°C) over GRound or over sea ice
       = AIJ(61) / NSURF*IDACC(1)
TG2:   Temperature of layer 2 (°C) over GRound or over sea ice
       = AIJ(62) / NSURF*IDACC(1)
TG3:   Temperature of layer 3 (°C) over GRound or over sea ice
       = AIJ(63) / NSURF*IDACC(1)
TG4:   Temperature of layer 4 (°C) over GRound or over sea ice
       = AIJ(64) / NSURF*IDACC(1)
TCLDB: Temperature (°C) at CLouD Bottom
       = AIJ(67) / [AIJ(6)+AIJ(7)+AIJ(8)]
TCLDT: Temperature (°C) at CLoud Top
       = AIJ(68) / [AIJ(6)+AIJ(7)+AIJ(8)]
TLAK:  Liquid Temperature (°C) over lake, vertically integrated
       = AIJ(69) / SHCW*AIJ(29)

T200:  Air Temperature (°C) at 200 mb (calculated in AIJK)
T500:  Air Temperature (°C) at 500 mb (calculated in AIJK)
T850:  Air Temperature (°C) at 850 mb (calculated in AIJK)
TOS:   Ocean Surface Temperature (°C)
       = TEMGS (GS,SS)  where
         GS = surface specific potenial enthalpy = OIJL(5)/DXYP*OIJL(1)
         SS = surface salinity = OIJL(9)/DXYP*OIJL(1)

Pressure
--------
PS:    Surface Pressure (mb) at bottom of atmosphere
       = AIJ(71)*.01 / IDACC(1) + 1013.25
PCLDB: Pressure of CLouD Bottom (mb), or the pressure below which the
       vertically integrated cloud optical depth is exactly .75
       = AIJ(72) / [AIJ(6)+AIJ(7)+AIJ(8)]
PCLDT: Pressure of CLouD Top (mb), or the pressure above which the
       vertically integrated cloud optical depth is exactly .75
       (note that PCLDT may exceed PCLDB, particularly if the column
       cloud optical depth is less than 1.5)
       = AIJ(73) / [AIJ(6)+AIJ(7)+AIJ(8)]
PSI:   Internal Sea Ice Pressure (mb)
       = AIJ(74)*.01 / IDACC(1)

PVS:   Surface Vapor Pressure (mb)
       = .01 * [AIJ(71)/IDACC(1) + 101325] * [AIJ(77)/IDACC(3)]
PSL:   Sea Level Pressure (mb) calculated from surface pressure and
       surface temperature using Trenberth et al. [1993] formula

Height
-----
ZOS:   Ocean Surface height (mm) above global mean sea level
       = AIJ(75)*1000 / GRAV*IDACC(1)
ZOBL:  Ocean Boundary Layer depth (m)
       = AIJ(76) / IDACC(1)

ZOSI:  Ocean Surface and Ice height (mm)
       = 1000*[AIJ(75)/GRAV + AIJ(21)/RHOW] / IDACC(1)
ZOSTE: Ocean Surface height (mm) due to STeric (thermal) Expansion
       = 1000*[AIJ(75)/GRAV*IDACC(1) - vertical sum OIJL(1)/IDACC(5) +
               + 1030*ZOCEAN]
Z200:  Geopotential height (m) at 200 mb (calculated in AIJK)
Z500:  Geopotential height (m) at 500 mb (calculated in AIJK)
Z850:  Geopotential height (m) at 850 mb (calculated in AIJK)

Humidity
--------
QAS:   Surface air specific humidity (g/kg)
       = AIJ(77)*1000 / IDACC(3)

Q200:  Specific humidity (g/kg) at 200 mb (from AIJK)
Q500:  Specific humidity (g/kg) at 500 mb (from AIJK)
Q850:  Specific humidity (g/kg) at 850 mb (from AIJK)
QRS:   Surface Relative Humidity (%)
       (see http://aom.giss.nasa.gov/DOC/RELHUM.TXT)

Source Runoff
-------------
RUNSG: Surface source RUNoff over Ground (mm/day)
       = AIJ(78)*NDAY / IDACC(1)
RUNU:  Underground source RUNoff over ground (mm/day)
       = AIJ(79)*NDAY / IDACC(1)
RUNI:  Source RUNoff over glacial Ice (mm/day)
       = AIJ(80)*NDAY / IDACC(1)

RUNS:  Surface source RUNoff over land (mm/day)
       = [AIJ(78)+AIJ(80)]*NDAY / IDACC(1)
RUNT:  Totale source RUNoff over land (mm/day)
       = [AIJ(78)+AIJ(79)+AIJ(80)]*NDAY / IDACC(1)


Eastward velocities and fluxes
------------------------------
UAS:   Eastward Surface Air wind (m/s)
       = AIJ(81) / IDACC(3)
USMA:  Eastward Momentum Stress on surface by Atmosphere (N/m^2)
       = AIJ(82) / DTS*IDACC(3)
UMSI:  Eastward Sea Ice Mass flux (10^6 kg/s, U grid)
       = AIJ(83) / DTS*IDACC(1)*10^6
UESI:  Eastward Sea Ice Heat flux (10^12 W, U grid)
       = AIJ(84) / DTS*IDACC(1)*10^12
USMSI: Eastward Momentum Stress of Sea Ice bottom (N/m^2, U grid)
       = AIJ(85) / DTS*IDACC(3)

UMAIR: Eastward AIR Mass flux (10^6 kg/s, U grid)
       = vertical sum of AIJL(2)*2 / NDYNA*IDACC(1)*10^6
UMWV:  Eastward Water Vapor Mass flux (10^6 kg/s, U grid)
       = vertical sum of AIJL(10) / DTS*IDACC(1)*10^6
UMO:   Eastward liquid Ocean Mass flux (10^6 kg/s, U grid)
       = vertical sum of OIJL(2)*2 / NDYNO*IDACC(1)*10^6
UMSALT:Eastward SALT flux (10^6 kg/s, Ugrid)
       = vertical sum of OIJL(10) / DTS*IDACC(1)*10^6
USI:   Eastward Sea Ice velocity (m/s, U grid)
       = UMSI*2*10^6 / [MSI(I)+MSI(I+1)]*DYP
       = AIJ(83)*[AIJ(I,1)+AIJ(I+1,1)] /
         / DTS*[AIJ(I,21)+AIJ(I+1,21)]*DYP*IDACC(1)

UEDSA: Approximate eastward Atmospheric Dry Static Energy flux
       (10^12 W, U grid), vertically integrated
UEWV:  Eastward Water Vapor (latent) Energy flux (10^12 W, U grid),
       vertically integrated
UEO:   Eastward Ocean potential Energy flux (10^12 W, U grid)
       = vertical sum of OIJL(6) / DTS*IDACC(1)*10^12

Northward velocities and fluxes
-------------------------------
VAS:   Northward Surface Air wind (m/s)
       = AIJ(86) / IDACC(3)
VSMA:  Northward Momentum Stress of surface by Atmosphere (N/m^2)
       = AIJ(87) / DTS*IDACC(3)
VMSI:  Northward Sea Ice Mass flux (10^6 kg/s, V grid)
       = AIJ(88) / DTS*IDACC(1)*10^6
VESI:  Northward Sea Ice Heat flux (10^12 W, V grid)
       = AIJ(89) / DTS*IDACC(1)*10^12
VSMSI: Northward Momentum Stress of Sea Ice bottom (N/m^2, U grid)
       = AIJ(90) / DTS*IDACC(3)

VMAIR: Northward AIR Mass flux (10^6 kg/s, V grid)
       = vertical sum of AIJL(3)*2 / NDYNA*IDACC(1)*10^6
VMWV:  Northward Water Vapor Mass flux (10^6 kg/s, V grid)
       = vertical sum of AIJL(11) / DTS*IDACC(1)*10^6
VMO:   Northward liquid Ocean Mass flux (10^6 kg/s, V grid)
       = vertical sum of OIJL(3)*2 / NDYNO*IDACC(1)*10^6
VMSALT:Northward SALT flux (10^6 kg/s, V grid)
       = vertical sum of OIJL(11) / DTS*IDACC(1)*10^6
VSI:   Northward Sea Ice velocity (m/s, V grid)
       = VMSI*2*10^6 / [MSI(J)+MSI(J+1)]*DXV
       = AIJ(88)*[AIJ(J,1)+AIJ(J+1,1)] /
         / DTS*[AIJ(J,21)+AIJ(J+1,21)]*DXV*IDACC(1)

VEDSA: Approximate northward Atmospheric Dry Static Energy flux
       (10^12 W, V grid), vertically integrated
VEWV:  Northward Water Vapor (latent) Energy flux (10^12 W, V grid),
       vertically integrated
VEO:   Northward Ocean potential Energy flux (10^12 W, V grid)
       = vertical sum of OIJL(7) / DTS*IDACC(1)*10^12

Miscellaneous
-------------
WAS:   Surface Air Wind speed (m/s)
       = AIJ(91) / IDACC(3)
EKT:   Turbulent Kinentic Energy lost by atmosphere at surface (W/m^2)
       = AIJ(92)*NSURF / DTS*IDACC(3)
HICBM: Heat of Ice Calving and Ice Berg Melting (W/m²)
       = AIJ(93) / IDACC(1)

SOS:   Ocean Surface Salinity (psu)
       = OIJL(1,9)*1000 / OIJL(1,1)


Unless otherwise indicated diagnostics are applied to (or averaged
over) entire model grid cells.  Only if the key word "over" followed by
a fraction of a grid cell does the diagnostic apply only to that
fraction.