Abstract

This report presents a description of data-extraction and interpolation procedures using the ECMWF/WMO Global Observational Data Set (ODS), an archive of unvalidated observational meteorological surface data measured at 00, 06, 12 and 18 UT. The archive covers the period 1 January 1980 to 31 December 1989. The data extraction software supplied with the data set has been adapted for use on a Unix computer system. Data can be selected on the basis of a specified time-period and area. A procedure for interpolating ODS data to trajectories or grids is described. These trajectories or grids are used as meteorological input for RIVM/LLO air pollution models. A procedure for the extraction of time series of ODS data has been developed. This data can be used for the calculation of longterm meteorological statistics for specified ODS stations.