"The World Data Centre for Greenhouse Gases (WDCGG) was established at the Japan Meteorological Agency (JMA) in October 1990 to make collection and distribution of data on the concentrations of greenhouse and related gases (CO2, CH4, CFCs, N2O, O3, CO, NOX, SO2, VOC, etc.) in the atmosphere and the ocean. The WDCGG collects data from the GAW observing network, research organizations, and other cooperative programmes. Data contributors report their data according to the format in the "Data Reporting Manual of the WMO WDCGG" (WDCGG No. 1). As of March 2005, 295 stations in 65 countries (the most recent statistics) have contributed observational data for greenhouse and related gases to the WDCGG. The WDCGG makes periodical publication of "WDCGG Data Report", "WDCGG CD-ROM", "WDCGG Data Catalogue" and "WDCGG Data Summary". The "Data Report" presents monthly and annual means and the "CD-ROM" contains hourly, daily, monthly and annual means of concentrations of greenhouse and related gases. Also recorded is information on contact persons, methods of measurement and calibration at the observation stations. The "Data Catalogue" provides an index of existing data along with procedures for data access. It also includes information on site environment, measurement procedures, and calibration techniques. The "Data Summary" is designed to describe analytical results on the past and present conditions of gas concentrations on local, regional, and global scales."