Volcanic Ash Advisory Center (VAAC) Best Practices: Moving Toward A Globally Harmonized Aviation Volcanic Ash Forecast System

Volcanic plumes and drifting ash clouds pose a risk to flight operations somewhere globally every day. Airborne ash plumes pose a significant hazard to aircraft and timely and accurate forecasts greatly help mitigate the risk of an encounter.

The world's nine (9) Volcanic Ash Advisory Centers (VAACs) provide products and services to address the volcanic ash hazard to aviation. These nine centers are operated by the meteorological authority within the state in which they are located. Each VAAC has its unique set of tools and procedures on how the data will be captured, displayed, analyzed and turned into a suite of products. The end products (e.g. Volcanic Ash Advisories (VAA) and Volcanic Ash Graphic (VAG)) are standardized through the International Civil Aviation Organization's International Airways Volcano Watch Operations Group (ICAO IAVWOPSG).

A derivative of this operations group has been the formation of a VAAC Best Practices team. VAAC Best Practices goal is to move toward a globally harmonized aviation volcanic ash forecast system. This is achieved through a focus on three specific themes, (1) the definition of “visible ash”, (2) data exchange, role of “the lead VAAC”, collaborative decision making and forecast validation, and (3) articulating forecast confidence and uncertainty. This presentation will highlight efforts underway with respect to collaborative decision making.