Fig. 4From: Estimation of emission mass from an eruption plume for the Aso volcano eruption, on October 8, 2016, using a four-dimensional variational methodComparison between observation and simulation for ash fall and lapilli. a Without 4D-Var. b With 4D-Var. Small windows in both figures are enlargements of large regions (0–4000 g/m2)Back to article page