NCEP/NCAR Reanalysis (R1) Sigma Level Data

SOURCE: Data Support Section Dataset ds090.0

DATA DESCRIPTION: NCEP/NCAR R1 reanalysis model (sigma) level daily data, regridded from 2.5 degree grid.

UPDATED THROUGH: Dec 2009

FORMAT: CCM2 History Tape (Jan 1979 - Dec 1996); NetCDF (Jan 1997 - current)

GRID: Global - T63 Gaussian (192 x 96)

LEVELS: (28 Sigma levels)

.9950,.9821,.9644,.9425,.9159,.8838,.8458,.8014,.7508,.6943,
.6329,.5681,.5017,.4357,.3720,.3125,.2582,.2101,.1682,.1326,
.1028,.0782,.0580,.0418,.0288,.0183,.0101,.0027

TIMES: 4 times daily: 00Z, 06Z, 12Z, 18Z.

CURRENT HOLDINGS: Jan 1979 - Dec 2009

FIELDS:

Description Name Units Levels
Zonal wind component U m s-1 all
Meridional wind component V m s-1 all
Temperature T K all
Specific humidity Q kg kg-1 all*
Surface pressure PS Pa surface
Surface geopotential PHIS m2 s-2 surface

*Values above 0.1682 do not appear to be reliable.

MSS Directory: /CA/NMC/SIGMA/

/CA/NMC/SIGMA/UPDATE/ (after March 1997)

Filename: Prior to 1997: T63yymmdd where yy=year, mm=month, dd=day=01,04,07,10,13,16,19,22,25,28, or 31; 3 days (12 time steps) per volume (though not always for end of month).

e.g. T63850101 contains data for 85,01,01,00Z through 85,01,03,18Z.

Filenames for holdings beginning January 1997 contain a four-digit year, one day per file, and have the file tag ".nc".

e.g. T6319970101.nc contains data for 00Z, 06Z, 12Z, and 18Z on
January 1, 1997 in NetCDF format.


Related Software: Code to convert CCM format to NetCDF (ccm2nc)


Other Products related to this Dataset: