The International Airways Volcano Watch (IAVW) of the International Civil Aviation Organization (ICAO) provides international arrangements for the monitoring of volcanic ash in the atmosphere and for providing warnings to the aviation community, in accordance with the ICAO Annex 3 – Meteorological Service for International Air Navigation – to the Convention in International Civil Aviation.

The IAVW is based on the cooperation of aviation and non-aviation operational units using information derived from observing sources and networks that are provided by States. The IAVW is coordinated by ICAO with the cooperation of other concerned international organizations.

The IAVW Operations Group (IAVWOPSG) was established in 2002 by the ICAO MET Divisional Meeting. The IAVWOPSG assists ICAO in the coordination and development of the IAVW. The IAVWOPSG is composed of experts from nine regional Volcanic Ash Advisory Centres (VAACs), other user States, the International Atomic Energy Agency (IAEA), the International Air Transport Association (IATA), the International Federation of Air Line Pilots’ Associations (IFALPA), the International Union of Geodesy and Geophysics (IUGG) (covering the World Organization of Volcano Observatories) and the World Meteorological Organization (WMO).

Structure of the IAVW:

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Area of responsibility of the nine regional VAACs:

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Observing component of the IAVW:

• Detection and tracking of volcanic ash in the atmosphere using:
• Data from volcano observatories
• Satellite imagery
• Aircraft reports (PIREPS)
• Other sources

Forecasting component of the IAVW:

• Numerical atmospheric dispersion models used by the VAACs

Products issued for the IAVW:

• Volcanic ash advisories issued by VAACs
• SIGMET issued by Meteorological Watch Offices (MWOs)
• Volcanic Ash NOTAM or ASHTAM issued by Area Control Centres (ACCs)

VAACs, MWOs and ACCs are authorized units for the provision of volcanic ash information to aviation within the framework of the IAVW.

Read more about the IAVWOPSG here