Data field inventory & file name interpretation
File
Prefix VARIABLE TYPE UNITS COMMENTS
------ -------- ---- ----- --------
ALL Contains many quantities
(use wgrib to see file inventory)
BVF2 Brunt-Vaisala frequency squared 0 1/s**2 6
CBUQ Covariance between u and q 0 m/s*gm/gm 5
CBTZW " between u and T 0 K*m/s 5
CBMZW " between u and v 0 m**2/s**2 5
CBQW " between q and VVEL 0 m/s*gm/gm 1,4,6
CBTMW " between v and T 0 K*m/s 5
CBTW " between T and VVEL 0 K*Pa/s 1,4,6
CBUW " between u and VVEL 0 Pa/s*m/s 1,4,6
CBVQ " between v and q 0 m/s*gm/gm 5
CBVW " between v and VVEL 0 m/s*Pa/s 1,4,7
CFNLF Cloud forcing net long wave flux A W/m**2 1,2
CFNSF Cloud forcing net solar flux A W/m**2 1,2
CPRAT Convective precipitation rate A kg/m**2/s 1,2,3,4
DSWRF Downward solar radiation flux A W/m**2 1,2
GPCPRAIN GPCP precipitation est - kg/m**2/s 7
HGT Geopotential height (Z) 0 gpm 5
ICEC Ice concentration (ice=1; no ice=0) - fraction 7
LAND Land-sea mask (1=land; 0=sea) - ---- 7
LHTFL Latent heat flux A W/m**2 1,2,3,4
MNTSF Montgomery stream function 0 m**2/s**2 6
MRDGRAIN merged precipitation est - kg/m**2/s 7
NLWRS Net long wave radiation (surface) A W/m**2 1,2
NSWRS Net short wave radiation (surface) A W/m**2 1,2,4
PEVPR Potential evaporation rate A W/m**2 6
POT Potential temperature 0 K 1,2,3,4
PRATE Total Precipitation rate A kg/m**2/s 1,2,3,4
PRES Pressure 06 Pa 5
PV Potential vorticity 0 m**2/s/kg 6
PWAT Precipitable water 06 kg/m**2 5
RH Relative humidity 0 percent 5
RUNOF Runoff A kg/m**2 1,3,4
SHTFL Sensible heat flux A W/m**2 1,2,3,4
SOILW Volumetric soil moisture content 6 fraction 3
SPFH Specific humidity (q) 06 kg/kg 5
STREAM Stream function 0 m**2/s 6
TCDC Total cloud cover A percent 1
TMP Temperature (T) 06A K 5,9
TMP sea surface temperature (SST) - K 7
UFLX Zonal wind stress (negative) A N/m**2 4,10
UGRD Zonal Wind (u) 06 m/s 5
ULWRF Upward long wave radiation flux A W/m**2 1,2
ULWRF Upward long wave radiation flux - W/m**2 7
UMAS Mass weighted zonal wind 0 gm/m*K*s 5
USWRF Upward solar radiation flux A W/m**2 1,2
VFLX Meridional wind stress (neg) A N/m**2 4,10
VGRD Meridional Wind (v) 06 m/s 5
VMAS Mass weighted meridional wind 0 gm/m*K*s 5
VPOT Velocity potential 0 m**2/s 6
VVEL Pressure vertical velocity 0 Pa/s 1,6
WEASD Water equiv. of accum. snow depth %6 kg/m**2 8
XPRATE corrected precipitation A kg/m**2/s 1,2,3,4
0=at analysis time
6=6 hour forecast
A=0-6 hour accumulation or average of forecast starting from the analysis
*=minimum or maximum in either a 6 or 24 window.
%=combination of observations and forecast
-=observed field
Comments:
1. cloud/convection parameterization dependent
2. radiation model dependent (include reflection, scattering)
3. soil/surface parameterization dependent
4. boundary layer parameterization dependent
5. observed quantity analyzed by model
6. derived quantity from assimilation
7. observed quantity
8. snow coverage heavily determined by observations & forecasts
(depth is not observed and is crudely estimated, see TEXT\DETAILS\SNOW)
9. temperature at mean sea level is observed sea surface temperature
10. upward fluxes in GRIB are positive (unlike convention)
Notes:
Inhomogeneous sampling/quality in troposphere, stratosphere and boundary layer
affect the quality of the analyses. In regions with few observations, the
analyses tend to be biased towards the climatology of the GCM used to make the
"first guess". Most quantities in the boundary layer are strongly influenced
by physical parameterizations of boundary layer, cloud, radiation, surface
properties, vegetation and soil. In general, the best analyzed quantities are
the tropospheric winds, geopotential heights and temperatures over land.
The radiation quantities are heavily dependent on the PREDICTED cloud cover.
Precipitation is the 0 to 6 hour forecast from the model (not determined by
rain gauges).
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