Figure 3

Ash observations and simulations for the 7 May 1902 eruption. (a) Estimated ash cloud velocity based on observations of ashfall east and south of the volcano; the numbers in brackets indicate the distance from the volcano. (b) Time series of ash thickness change (mm h⁻¹) averaged over the two islands for the Control, Alternative Wind and Flat Topography experiments. The final averaged ash thickness (mm) is shown on the right-hand side of the plot. The periods of observed ashfall over the two islands is shown by the dotted lines at the panel top. (c) Cross-section of the maximum ash thickness against longitude. Local maxima over St Vincent, east (windward) of St Vincent, and over Barbados are evident. The maximum in topography of the islands is shaded in light grey.