The ECMWF Re-Analysis (ERA40) is a global atmospheric analysis of many conventional observations and satellite data streams for the period Sept,1957- Aug,2002. There are numerous data products that are separated into dataset series' based on resolution, vertical coordinate reference, and likely research applications. Descriptions of the series organization and direct links to information about all ERA40 products are available.

This dataset contains 11 variables on 23 pressure surfaces on an equally spaced global 2.5 degree latitude-longitude grid. Monthly means have been computed for each analysis hour as well as a daily mean.