PVAHA considers a magnitude-frequency distribution of eruptions and associated volcanic ash load attenuation relationships and integrates across all possible events to arrive at an annual exceedance probability for each site across a region of interest.
This technique considers a magnitude-frequency distribution of eruptions, associated volcanic ash load attenuation relationships and prevailing meteorological conditions and integrates across all possible events to arrive at a combined probability of exceedance for a site of interest.
The VAPAH algorithm considered a magnitude-frequency distribution of eruptions and associated volcanic ash load attenuation relationships for the Asia-Pacific, and integrated across all possible events to arrive at an annual exceedance probability for sites of interest.
The Probabilistic Volcanic Ash Hazard Analysis (PVAHA) framework considers the magnitude-frequency distribution of eruptions and associated volcanic ash load attenuation relationships to produce and statistically emulate volcanic ash hazard for all events across a region of interest.
While the field is still relatively young (Lindsay et al. 2010), previous work has suggested that the spatial distribution of eruptions within the AVF has been relatively stable since the formation of the 15th eruption (Bebbington 2013; Le Corvec et al. 2013a).
The framework named here, Probabilistic Volcanic Ash Hazard Analysis (PVAHA) considers the magnitude-frequency distribution of eruptions and associated volcanic ash load attenuation relationships and produces an integrated description of volcanic ash hazard for all events across a region of interest.
We are not contending that the magnitude frequency distributions of eruption earthquakes always show exponential or two power-law relationships.
The toolbox includes a series of graphical user interfaces that collect, analyze and pre process input data, create distributions of eruption source parameters based on a wide range of probabilistic eruption scenarios, run Tephra2 using the generated input scenarios and provide results as exceedence probability maps, probabilistic isomass maps and hazard curves.
Because this study employs an equal probability distribution of an eruption occurring at any location in the AVF, the percentage values also represent the likelihood that a future AVF eruption will generate the number of evacuees listed in each class.
Fig. 2 a Distribution of the eruption vents on September 28 , 2014
