Uncertainty Quantification of Eruption Source Parameters Estimated From Tephra Fall Deposits

Uncertainty quantification (UQ) in eruption source parameters, like tephra volume, plume height, and umbrella cloud radius, is a challenge for volcano scientists because deposits are often sparsely sampled due to burial, erosion, related factors. We find that UQ improved by coupling an advection-diffusion model with two Bayesian inversion approaches: (a) robust but computationally expensive Generalized Likelihood Estimation algorithm, (b) more approximate inexpensive parameter estimation algorithm combined first-order, second-moment uncertainty estimation. apply the methods one fall unit from 2070 BP El Misti (Peru) obtain: Tephra mass 0.78–1.4 × 1011 kg; radius 4.5–16.5 km, height 8–35 km (95% confidence intervals). These broad ranges demonstrate significance of classification based on mapped deposits, which has implications hazard management.