Figure 7
From: An analysis of the issuance of volcanic alert levels during volcanic crises
Controls on the issuance of VALs due to changes in monitoring at volcanoes that have had multiple eruptions. Color shaded fields group volcanoes values with similar monitoring capacity. A) For `Closed Vent’ volcanoes: Blue area represents 3 volcanoes, 9 eruptions all have monitoring level 2. Green area represents 5 volcanoes, 15 eruptions 86% of which have a monitoring level of 2. B) For `Open Vent’ volcanoes: Red area represents 4 volcanoes with 48 eruptions, 75% of which have monitoring level 0, blue area represents 11 volcanoes, 53 eruptions 73.5% of which have monitoring level 2, green area represents 6 volcanoes, 16 eruptions 75% of which have level 3(+) monitoring.