Ash Metrics for European and Trans‐Atlantic Air Routes During the Eyjafjallajökull Eruption 14 April to 23 May 2010

Metrics for the risk associated with the threat that airborne volcanic ash particles pose to commercial jet aircraft are presented using simulations based on a Lagrangian particle transport and dispersion model driven by satellite measurements for the Eyjafjallajökull volcanic eruption, Iceland, for the period 14 April to 23 May 2010. The study utilizes a four‐dimensional data set of simulated ash concentrations together with European and trans‐Atlantic air routes to determine metrics corresponding to the total mass intercepted (defined as the dose), the mass interception rate (the dose rate), and the concentration (the exposure) over time (the dosage) that a jet aircraft encounters along the air route. The methodology can be used as a logistical and flight planning tool in a forecast mode and also in hindcast mode to assess the extent of airline fleet exposure to ash following an eruption, thereby providing operators with information useful for flight safety.