BET_VH: exploring the influence of natural uncertainties on long-term hazard from tephra fallout at Campi Flegrei (Italy)

In this paper, we explore the effects of the
intrinsic uncertainties upon long-term volcanic hazard
by analyzing tephra fall hazard at Campi Flegrei, Italy,
using the BET_VH model described in Marzocchi et al.
(Bull Volcanol, 2010). The results obtained show that
volcanic hazard based on the weighted average of all
possible eruptive settings (i.e. size classes and vent locations)
is significantly different from an analysis based
on a single reference setting, as commonly used in
volcanic hazard practice. The long-term hazard map
for tephra fall at Campi Flegrei obtained here accounts
for a wide spectrum of uncertainties which are usually
neglected, largely reducing the bias intrinsically
introduced by the choice of a specific reference setting.
We formally develop and apply a general method to
recursively integrate simulations from different models
which have different characteristics in terms of spatial coverage, resolution and physical details. This outcome
of simulations will be eventually merged with field data
through the use of the BET_VH model.

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