ECMWF ERA40 Reanalysis Project

Project Description
The ERA40 project is a global atmospheric analysis of many conventional observations and satellite data streams for the period September, 1957 - August, 2002. Analyses were produced daily at 00Z, 06Z, 12Z and 18Z. The atmospheric model was run with the following resolution:

* 60 levels in the vertical;
* T159 spherical-harmonic representation for basic dynamic fields;
* a reduced Gaussian grid with approximately uniform 125km spacing for surface and other grid-point fields.

Detailed descriptions of the project and the data assimilation system are available in The ERA-40 Project Report Series and ERA-40 Archive Plan documents from ECMWF.

http://www.ecmwf.int/publications/library/do/references/list/192
http://www.ecmwf.int/research/era/Products/Archive_Plan/index.html

[Source: The ERA-40 ARCHIVE AT NCAR Home Page
http://dss.ucar.edu/pub/era40/]