The WMO/CAS OPAG-EPAC Expert Team on World Data Centres (ET-WDC) was formally established in 2006 by CAS-XIV  but has a history of activities that dates back to the 1990s. The chair of the ET-WDC is a member of the OPAG EPAC Scientific Steering Committee (SSC), the steering body of the Global Atmosphere Watch (GAW) programme. This expert team meets every 1-2 years and holds teleconferences 2-4 times per year to discuss issues of data management, and data access, metadata handling and exchange, data archiving, links to WIGOS and the WMO Information System (WIS), etc.
 WMO (2006), Commission for Atmospheric Sciences : fourteenth session, Cape Town, 16-24 February 2006, abridged final report with resolutions and recommendations (WMO No. 1002), World Meteorological Organization, Geneva, Switzerland, http://www.wmo.int/pages/prog/arep/cas/documents/CAS_14_E.pdf