ALMA Standard Variables

Original Resource

Expected Range of Values

A summary of quality control values for the ALMA standard variable definitions are given below. Sign conventions correspond to the 'traditional' choice.

The variables have been grouped into eight general categories:

In the case of the meteorological forcing the hourly time scale was considered to provide a range of values. For the other categories it was considered that the daily time scales would be appropriate. Thus it must be kept in mind that if for instance output is generated from the land-surface scheme every hour the values may exceed the provided range.

This Web page is also used by the Quality program. It is thus necessary to know for each variable if it is sensitive to the sign convention and which is its level of importance in the output file.If the variable is sensitive to the sign convention then the column will have a "Y". For the output level the following coding is used : F=forcing, M=Mandatory, R=Recommended and O=Optional.

Meteorological Forcings:
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
Wind_N 
m/s
-75.0
75.0
N
F
Wind_E
m/s
-75.0
75.0
N
F
Rainf
kg/m2/s
0.0
0.02
N
F
Rainf_LS
kg/m2/s
0.0
0.02
N
F
Rainf_C
kg/m2/s
0.0
0.02
N
F
Snowf 
kg/m2/s
0.0
0.0085
N
F
Snowf_LS 
kg/m2/s
0.0
0.0085
N
F
Snowf_C 
kg/m2/s
0.0
0.0085
N
F
Tair 
K
213.0
333.0
N
F
Qair 
kg/kg
0.0
0.03
N
F
PSurf 
Pa
5000.0
110000.0
N
F
SWdown
W/m2
0.0
1360.0
N
F
LWdown
W/m2
0.0
750.0
N
F
CO2air
ppmv
160
600
N
F

General energy balance components:
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
SWnet
W/m2
0.0
1200.0
N
M
LWnet
W/m2
-500.0
510.0
N
M
Qle
W/m2
-700.0
700.0
Y
M
Qh
W/m2
-600.0
600.0
Y
M
Qg
W/m2
-500.0
500.0
Y
M
Qf
W/m2
-1200.0
1200.0
Y
R
Qv
W/m2
-600.0
600.0
Y
O
Qtau
N/m2
-100.0
100.0
N
R
Qa
W/m2
-50.0
50.0
N
O
DelSurfHeat
J/m2
-500.0
500.0
N
R
DelColdCont
J/m2
-600.0
1000.0
N
R

General water balance components:
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
Snowf
kg/m2s
0.0
0.0085
N
M
Rainf
kg/m2/s
0.0
0.02
N
M
Evap
kg/m2/s
-0.0003
0.0003
Y
M
Qs
kg/m2/s
0.0
5.0
Y
M
Qrec
kg/m2/s
0.0
5.0
Y
O
Qsb
kg/m2/s
0.0
5.0
Y
M
Qsm
kg/m2/s
0.0
0.005
N
M
Qfz
kg/m2/s
0
0.005
N
M
Qst
kg/m2/s
0.0
0.005
N
R
DelSoilMoist
kg/m2
-2000.0
2000.0
N
M
DelSWE
kg/m2
-2000.0
2000.0
N
M
DelSurfStor
kg/m2
-2000.0
2000.0
N
R
DelIntercept
kg/m2
-100.0
100.0
N
R

Surface state variables:
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
SnowT
K
213.0
280.0
N
M
VegT
K
213.0
333.0
N
M
BaresoilT
K
213.0
343.0
N
M
AvgSurfT
K
213.0
333.0
N
M
RadT
K
213.0
353.0
N
M
Albedo
-
0.0
1.0
N
M
SWE
kg/m2
0.0
2000.0
N
M
SWEVeg
kg/m2
0.0
500.0
N
O
SurfStor
kg/m2
0.0
2000.0
N
M

Subsurface State Variables
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
SoilMoist
kg/m2
0.0
2000.0
N
M
SoilTemp
K
213.0
333.0
N
R
SMLiqFrac
-
0.0
1.0
N
O
SMFrozFrac
-
0.0
1.0
N
O
SoilWet
-
-0.2
1.2
N
M

Evaporation components:
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
PotEvap
kg/m2/s
-0.0006
0.0006
Y
R
ECanop
kg/m2/s
-0.0003
0.0003
Y
R
TVeg
kg/m2/s
-0.0003
0.0003
Y
M
ESoil
kg/m2/s
-0.0003
0.0003
Y
M
EWater
kg/m2/s
-0.0003
0.0003
Y
R
RootMoist
kg/m2
0.0
2000.0
N
M
CanopInt
kg/m2
0.0
100.0
N
R
EvapSnow
kg/m2/s
-0.0003
0.0003
N
R
SubSnow
kg/m2/s
-0.0003
0.0003
N
R
SubSurf
kg/m2/s
-0.0003
0.0003
N
R
ACond
m/s
0.0
1.0
N
M

Streamflow:
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
Dis
m3/s
0.0
500000.0
N
O
WaterTableD
m
0.0
50.0
N
O

Cold Season Processes:
Variable
Units
Lower Limit
Upper Limit
Sign convention sensitivie QC
Output level
SnowFrac
-
0.0
1.0
N
O
RainfSnowFrac
-
0.0
1.0
N
O
SnowfSnowFrac
-
0.0
1.0
N
O
IceFrac
-
0.0
1.0
N
O
IceT
m
0.0
2.0
N
O
Fdepth
m
0.0
5.0
N
O
Tdepth
m
0.0
5.0
N
O
SAlbedo
-
0.0
1.0
N
R
SnowTProf
K
213.0
280.0
N
R
SnowDepth
m
0.0
8.0
N
R
SliqFrac
-
0.0
0.2
N
R