This is the dataset for “Volcanic ash ice-nucleating activity can be enhanced or depressed by ash-gas interaction in the eruption plume” in Earth and Planetary Science Letters. The data files include the following:

tephra_feldspar_quartz_INA.xlsx

First tab is replicate ice nucleation data for non-treated and treated tephra, feldspar and quartz samples in water. Columns list temperatures (T) and corresponding ice-active site densities (ns) for each droplet array experiment. Upper limit (UL) and lower limit (LL) ns values were calculated by Poisson Monte Carlo simulations. A summary table provides the samples' ice-nucleating activities (INAs) in terms of the T at which ns is approximately equal to 5 per cm2 (Tns≈5cm-2). These data are presented in Figures 2 and 3 of the paper.

Second tab is ice nucleation data for non-treated tephra samples in leachates and rinsed treated tephra samples in water (supplementary experiments to test for solute effects on INA). Columns list temperatures (T) and corresponding ice-active site densities (ns) for each droplet array experiment. Upper limit (UL) and lower limit (LL) ns values were calculated by Poisson Monte Carlo simulations. These data are presented in Figures 5 and 6 of the paper.

leachate_concentrations.xlsx

This is leachate concentration data for non-treated and treated tephra, feldspar, quartz and glass samples in water. These include Na, K, Ca, Mg and Fe concentrations measured by inductively coupled plasma - optical emission spectroscopy and SO42- and Cl- concentrations measured by ion chromatography. These data are presented in Figure 4 of the paper.

anhydrite_INA.xlsx

This is ice nucleation data for a natural anhydrite sample tested in water in this study (droplet array experiments) and a dry-suspended anhydrite sample tested by Grawe et al. 2018 (aerosol flow tube experiments). The columns list temperatures (T) and corresponding droplet frozen fractions (fice) and/or ice-active site densities expressed in terms of surface area (ns) or mass (nm). These data are presented in Figure S1 of the Supplementary Information.

glasses_INA.xlsx

This is replicate ice nucleation data for non-treated and treated glass samples in water (supplementary experiments to test for CaSO4 effects on INA). Columns list temperatures (T) and corresponding ice-active site densities (ns) for each droplet array experiment. Upper limit (UL) and lower limit (LL) ns values were calculated by Poisson Monte Carlo simulations. These data are presented in Figure S2 of the Supplementary Information.