Fig. 4
a. Illustration of significant timescales for InSAR measurement (satellite repeat time, 1observation period as estimated by Parker et al., 2015), decision makers with responsibility for volcanic hazard (indicative durations) and duration of unrest and eruption (2unrest periods as described by Phillipson et al., 2013). Examples of eruptions with different durations of pre-eruptive unrest are indicated by volcano name and eruption date (López et al., 2012; Delgado et al., 2014), while volcano name and arrows show episodes of unrest. b. Cumulative number of InSAR measurements of volcano deformation that have captured various durations – note non-linear time scale on x-axis