Codelist is a type of XML element whose value is not a free text, but is limited to a set of predefined value.

The standard codelists of ISO 19139 are given at ISO website.

Several codelists are extended in WMO Core Metadata profile, and the computer-readable version is available in the folder http://wis.wmo.int/2012/codelists/. This contains the current version, but may also contain earlier versions as well (these are identified by their version number in the name of the file). A more user-friendly presentation of the lists is also available.

The latest version is http://wis.wmo.int/2012/codelists/WMOCodeLists.xml.