ICAO Introduces New and Improved Volcanic Ash Forecast

ICAO has started providing an upgraded Quantitative Volcano Ash (QVA) forecast information service, offering greater analysis for aircraft operators. This includes forecasting how much ash is expected to be in the atmosphere rather than just its location.

The new service came into effect late last year. Two of nine specialist Volcanic Ash Advisory Centres (VAACs)—London and Toulouse—will initially provide the upgraded QVA forecasts before a global rollout.

Eventually, all nine ICAO-designated VAACs worldwide will provide detailed forecasts using a combination of volcano data; satellite-based, ground-based, and aircraft observations; and forecasting models. ICAO recommends that all nine should issue QVA forecasts from Nov. 26, 2026. Conventional charts will continue to be provided in parallel until then.

The new service provides ash concentration and probability forecasts up to 60,000 feet in 5,000-foot layers. Data is provided in three-hourly increments, and the service is provided free of charge to registered users. A NATS Aeronautical Information Circular explained that “QVA forecasts will provide higher resolution detail,” providing both a “single, specific forecast snapshot” alongside longer-term projections within the boundaries of an eruption.

The UK Met Office’s Matthew Hort said that operators now have the opportunity to “use certified engine susceptibility for flight-route planning,” which will lead to higher efficiency in accordance with safety management programs.