This is the sixth ECMWF-users' newsletter.  To get copies of previous
newsletters, use anonymous FTP to ncardata.ucar.edu [128.117.8.111] and
change directory to datasets/ds111.2/news.

			3 December 1992

CONTENTS:

	o Basic Consolidated Dataset (ds111.2) updated through September 1992
	o Year-month means dataset (ds111.5) updated through September 1992
	o Information on history of model changes available
	o Reorganization of FTP area subdirectories for ECMWF datasets
	o GRIB document available on-line
	o New software for extracting grids available

============================================================================

	Basic Consolidated Dataset (ds111.2) update

The Basic Consolidated Dataset (ds111.2) has been updated with the April -
September 1992 data.  If you are planning to use the data on NCAR's Cray, 
you can obtain the listing of the volume serial numbers containing the data 
from the file datasets/ds111.2/MASTER, via anonymous FTP to ncardata.ucar.edu.
This file is also on the Mass Store under the name /DSS/D/DS1112.

Things are still a little unsettled at NCDC, but we hope that we will again
be receiving updates to this dataset every three months.

Beginning January 1992, the 925 mb level is present in this dataset.  The
documentation has been updated to reflect this.
===
	Year-month means dataset (ds111.5) update

Monthly mean values have been computed from the ds111.2 data for the
period January - September 1992.  The 0Z means are in /DSS/Y14885 and the
12Z means are in /DSS/Y14886.  These files will be updated when the 
data for October - December 1992 is received.  You can obtain the complete
listing of the volume serial numbers containing the data from the file
datasets/ds111.5/MASTER, via anonymous FTP to ncardata.ucar.edu.  This file
is also on the Mass Store under the name /DSS/D/DS1115.
===
	Information on history of model changes available

We have received more copies of the ECMWF document, "The Description of
the ECMWF/WCRP Level III-A Global Atmospheric Data Archive."  This document
contains a brief description of the analysis and forecast system used,
and more importantly, a history of all model changes.  If you are
working with the ECMWF data over long periods of record and need this
document, email or telephone me and I will send you a copy.  If you 
don't need a copy of this document, but want to verify discontinuous 
behavior in the data at a particular date, call me and I will check 
if a model change was implemented on that date.  If you would like a
copy of only the model description (3 pages), call me and I will fax 
or mail it to you.
===
	Reorganization of FTP area subdirectories for ECMWF datasets

If you have used the FTP area to retrieve files from the ds111.x series
of datasets, you have probably already noticed that two new subdirectories
have been added to each directory.  Because the number of files, particularly
access codes, has been increasing, subdirectories for software and for
format information have been added to each directory.  Each subdirectory
has its own README file which describes its contents.  This subdivision
should make it easier to find the files you need.
===
	GRIB document available on-line

The subdirectory "format" in each of the directories for the ds111.x 
datasets contains four files.  The first is a README file, which describes
the contents of the other three.  The file "format_grib" contains a WMO 
document which describes the official GRIB data format.  However, ECMWF does 
not use the same parameter table (Table 2) to define the type of data.  
The file "parm_table" contains the parameter code number used by ECMWF 
for each of the possible data types, and should be used instead of the
Table 2 in the text of the "format_grib" file. Other differences between 
the WMO version of the GRIB format and the ECMWF version are listed in the 
file format_diffs, as the WMO document describes the "Edition 1" version
of GRIB, but ECMWF uses "Edition 0", as described in the hardcopy document
"FM 92 GRIB".
===
	New software for extracting grids available

The "software" subdirectories of ds111.0 and ds111.2 now contain "select"
code.  These programs allow the user to specify a subset of grids (by
parameter, level, date, etc.) which will be written (in the original GRIB
format) to an output file or files.  The output files can be processed
later on the Cray or another machine.  

============================================================================

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If you are interested in ordering any ECMWF/TOGA data, or any other data
from NCAR's archives, please contact me.  I can be reached at
ilana@ncar.ucar.edu or by phone at (303)497-1214.

Ilana Stern
Data Support Section
National Center for Atmospheric Research