Here is a brief summary on the ECMWF/TOGA data sets, to help you decide which set might be most appropriate for your needs, and to help you get started in using it. ds111.0 ECMWF TOGA Global Advanced Operational Upper Air Spectral Analyses ds111.1 ECMWF TOGA Global Advanced Operational Surface Analyses ds111.2 ECMWF TOGA Global Basic Surface & Upper Air Analyses ds111.3 ECMWF TOGA Global Supplementary Fields ds111.4 ECMWF TOGA Global Initialized Analyses on Model (Hybrid) Levels ds111.5 DSS-derived Year-Month Means From ECMWF TOGA Basic Analyses ds111.0, ds111.1, ds111.3 have data for January 1985 - December 1995. ds111.2 currently has data for January 1985 - March 1996. ds111.4 has data for the period July 1990 - June 1991 and will not be updated further. ds111.5 has data for the period January 1985 - December 1995. All are in ECMWF GRIB format, fixed-length records, but the length of a physical record (blocksize) varies from dataset to dataset. Often a logical record (a GRIB message) spans several physical records, with any extra space padded out by blanks. The subdirectory "format" contains various documents describing the data format used in these datasets. The file format_grib contains a WMO document which describes the official GRIB data format. However, ECMWF does not use the same parameter table to define the type of data. You will need the file parm_table, which contains the parameter code number used by ECMWF for each of the possible data types. Other differences between the WMO version of the GRIB format and the ECMWF version are listed in the file format_diffs. If you would like a printed copy of the data format, the ECMWF document "FM 92 GRIB" (not identical to the online WMO version) is available from the Data Support Section by email to datahelp@ncar.ucar.edu. There is a mailing list which exists to distribute bulletins from NCAR/DSS and ECMWF about these datasets, such as announcements of new data availability, problems which have been discovered, and changes to software. If you wish to be added to this mailing list, send email to Ilana Stern at ilana@ncar.ucar.edu. To see previous bulletins, retrieve the files in the subdirectory datasets/ds111.2/news. Even though the "news" subdirectory is under the ds111.2 directory, the bulletins are relevant to users of all of the ECMWF/TOGA datasets. *************************************************************************** IMPORTANT notice if you wish to use any of these datasets on a computer other than the NCAR Cray: ECMWF permits NCAR to distribute these datasets ONLY to US scientists working for the government or universities, scientists visiting such US institutions, and Canadian scientists affiliated with UCAR member organizations. You must sign and return a permission form before we can process your order. This form can be found in the subdirectory for each of the ECMWF datasets, in the file permission_form. *************************************************************************** ds111.0: Advanced Operational Dataset (upper-air): Fields are uninitialized analyses 4x/day (0Z, 6Z, 12Z, 18Z) 14 or 15 pressure levels (1000, 850, 700, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, and 10 mb; 925 mb beginning 1 January 1992) Variables at each level: geopotential, temperature, vertical velocity, u- and v- components of horizontal wind, and relative humidity. Data is stored as spherical harmonics at T106 after May 1985, T63 before. Blocksize: Jan 1985 - May 1985 8400 bytes Jun 1985 - 16 Sep 1991 23280 bytes 17 Sep 1991 - Dec 1995 11640 bytes. Jan 1996 - present 24152 bytes. About 290 Mb/month. ds111.1: Advanced Operational Dataset (surface and diagnostic fields): Fields are uninitialized analyses 4x/day (0Z, 6Z, 12Z, 18Z) Variables are surface pressure, surface temperature, soil moisture, snow depth, MSL pressure, total cloud amount, u- and v-components of 10-meter wind, 2-meter temperature and dewpoint, deep-soil wetness, deep-soil temperature; after July 1986, surface geopotential, land-sea mask, surface roughness, albedo, climate deep-soil wetness, climate deep-soil temperature. Data is stored on N80 Gaussian grid (approx 1.125 degree) after May 1985, N48 (1.875 deg) before. Blocksize is 25680 bytes after May 1985, 18720 before. Beginning January 1990, total cloud amount is no longer in ds111.1 but in ds111.3 instead. About 230 Mb/month. ds111.2: Basic Dataset (surface and upper air): Fields are uninitialized analyses 2x/day (0Z and 12Z) 14 or 15 pressure levels (same as ds111.0) Upper air variables same as ds111.0 Surface variables are surface pressure, surface temperature, MSL pressure, u- and v-components of 10-meter wind, 2-meter temperature and dewpoint, surface geopotential, land-sea mask. Data is stored as 2.5 degree grid. Blocksize is 10560 bytes through February 1996. Beginning March 1996, the blocksize is 10680 bytes. Beginning July 1998, the blocksize is 21152 bytes. This is essentially a lower-resolution version of the first two data sets. About 130 Mb/month. ds111.3: Supplementary Fields Dataset: Fields are derived from 6-hr forecasts valid for 0Z and 12Z (this does not adequately represent the diurnal cycle) through Dec 1989; beginning January 1990, fields are derived from forecasts for 0Z, 6Z, 12Z, 18Z. Variables are surface sensible heat flux, surface latent heat flux, net shortwave and longwave radiation at the surface, net shortwave and longwave radiation at the top of the atmosphere,and u- and v-components of surface wind stress; beginning January 1990, total cloud amount. Data is stored as in ds111.1 Blocksize is 12840 bytes through December 1989. Beginning January 1990, the blocksize is 25680 bytes (the same as ds111.1). About 50 Mb/month through December 1989. About 110 Mb/month beginning January 1990. 111.5: Basic Dataset (consolidated): Fields are the analyses from ds111.2 averaged over each month, for 0Z and 12Z separately. 14 or 15 pressure levels (same as ds111.2) Upper air variables same as ds111.2 Surface variables are same as ds111.2 Data is stored as 2.5 degree grid. Blocksize is 10560 bytes. About 26 Mb/year per time (52 MB/year for both 00Z and 12Z).