Meaning
volcanic-ash-advisories is a global, current-state Data Product for volcanic ash that can affect aviation. It reports the latest advisory for each volcano, not a history of eruptions and not a complete catalogue of volcanic activity.
Provider and coverage
The initial Provider is the public Australian Bureau of Meteorology relay of the nine ICAO Volcanic Ash Advisory Centres (VAACs). Together the centres cover the world's flight-information regions. The channel refreshes every 15 minutes and retains only observations no older than 26 hours.
Contract
Each feature is a Point at the advisory's stated volcano position. Required properties preserve the issuer and identity: volcano_name, vaac, advisory_number, and advisory_time. Optional details retain the ash-cloud description, eruption details, information sources, and next-advisory time.
Boundaries
An advisory is issued for ash hazards, so an eruption without observed or reported airborne ash may be absent. The product is informational and is not a substitute for official flight planning, NOTAMs, SIGMETs, or operator safety procedures. Smithsonian weekly volcanic activity remains a separate product for catalogue identity and reviewed context.