The WOCE Global Hydrographic Climatology has been derived using World Ocean Data 1998 (WOD98), described in dataset ds285.0, and profiles from the WOCE Hydrographic Programme, with the exception of a few cruises, collected between 1990 and 1998. Several other small data collections from Germany, Russia, and France were also included. Data quality checks, cruise bias corrections, averaging on isopycnal surfaces, and finally optimal interpolation on 45 standard levels was used to determine the climatologies and error estimates of salinity, temperature, oxygen, and a suite of nutrients. Many more details and figures are available in Gouretski et al. 2004, WOCE Global Hydrographic Climatology.