Background information about this type of data may be found in An Introduction to Atmospheric and Oceanographic Datasets.

As with any high volume operational model production system there were times when late file postings and network outages interrupted data acquisition and processing for the archive. The CISL/DSS made a "best" effort to obtain a complete archive time series.

CISL/DSS selected the FNL analysis over all others because it used the most complete set of observations and was run last in the sequence of operational global models. The FNL is likely the best option for a long-term operational model archive from NCEP. Note that NCEP also made the Aviation (AVN) Analyses using the same model, but DSS did not collect them.

Correspondence received from NCEP in June 1992 indicates that the production of the global analyses was given second priority. They considered it their most expendable product. When they experienced hardware failures and the like, they gave the MRF model priority, and sometimes (especially at 00Z) this meant skipping the final run which produced the global analyses.

Please see the NCEP documents About the Global Parallel System. and EMC Model Documentation for more details.

Land skin temperature and sea surface temperature are in one field.

A memo about SST analysis is here.

As in DS082.0, the temperature may still actually be a virtual temperature.

NCEP dropped Tmax and Tmin in late 1999

     1000  z t u v rh
    bound  t u v
      10m  u v
       2m  t tmax tmin q rh
      col  rh pwat
      sfc  sfcp z sfct
      sfc  weasd landsea iceconc
 soil-010  tsoil waterc
 soil-200  tsoil waterc
      msl  slp