NCEP/NCAR Reanalysis, 6-hourly

6-hourly: Pressure Level

The NCEP/NCAR Reanalysis 1 project is using a state-of-the-art analysis/forecast system to perform data assimilation using past data from 1948 to the present. A large subset of this data is available from Physical Sciences Division (PSD) at NOAA in its original 4 times daily format and as daily averages. However, the data from 1948-1957 is a little different, in the regular (non-Gaussian) gridded data. That data was done at 8 times daily in the model, because the inputs available in that era were available at 3Z, 9Z, 15Z, and 21Z, whereas the 4x daily data has been available at 0Z, 6Z, 12Z, and 18Z. These latter times were forecasted and the combined result for this early era is 8x daily. The local ingestion process took only the 0Z, 6Z, 12Z, and 18Z forecasted values, and thus only those were used to make the daily time series and monthly means here.

Kalnay et al., (1996). The NCEP/NCAR 40-year reanalysis project, Bull. Amer. Meteor. Soc., 77, 437-470

Air Temperature (degK)
Geopotential Height (m)
Omega (Pascal/s)
Relative Humidity (%)
Specific Humidity (Kg/kg)
U-Wind (m/s)
V-wind (m/s)
Zonal Global by 2.5 deg
Meridional Global by 2.5 deg
Vertical 17 pressure levels (hPa): 1000, 925, 850, 700, 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, 20, 10 (All except Omega (to 100mb), Specific Humidity, and Relative Humidity (to 300mb))  
Temporal Jan 1, 1948 to last day of (present - 1) month by 6 hours
Static? no
Volume ~300MB per variable per year (Air Temperature, Geopotential Height, Omega, Specific Humidity)
~125MB per variable per year (Relative Humidity)
~550MB per variable per year (U-Wind, V-Wind)
Server public:
Acquired Oct 28, 2016 (Updated Monthly)
APDRC contact

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