Fig. 5From: Volcanic plume measurements using a UAV for the 2014 Mt. Ontake eruptionSulfur dioxide column amount change with time during the SO2 flux flights; a on November 20, 2014 (red line in Fig. 3), b on November 21, 2014 (blue line in Fig. 3), c on June 2, 2015 (red line in Fig. 4) and d on June 2, 2015 (blue line in Fig. 4). Times p–w in the plots correspond to the respective positions in Figs. 3 and 4 Back to article page