Scenario Types

Hazard maps can also be classified according to the scenarios used for hazard zonation. Many maps have zones that do not consider any specific scenario (full map list from the database here), rather they strive to depict all possible outcomes.

Others base hazard zones on the most-likely (e.g. Dominica, 2005; full map list here) or worst-case (e.g. Taal, Philippines, 2011; full map list here) scenario, or may consider scenarios related to specific past eruptions (e.g. Makushin, USA, 2000; full map list here) either at the volcano in question or those of analog volcanoes (e.g. Hayes, USA, 2002; full map list here).

Many maps, especially those that use scenario-based modeling, consider hazard processes of different volumes or eruptions of different sizes (e.g. eruption VEI – El Misti, Peru, 2014; full map list here) or styles (e.g. effusive vs. explosive eruption; full map list here). Probabilistic-modeling based maps consider many thousands of scenario combinations (e.g. Snake River Plain, USA, 2018; full map list here).

Many crisis hazard maps are based on the specific or current conditions at the time the map is made and serve as short-term forecasts (e.g. Villarrica, Chile, 2015; Holuhraun, Iceland, 2015; full map list here).

Still other maps may consider scenarios related to the possible location (see full map list here) of future volcanic activity (i.e. scenarios are based on likely vent- or fissure- opening locations, e.g. Mauna Loa, USA, 2017; or on the possible eruptive center, e.g. Emmons Lake, USA, 2006), the season (full map list here) during which an eruption might occur (usually for tephra, gas, or lahar hazard zones, e.g. Colima, Mexico 2003), or even the potential composition of a future eruption (e.g. Lassen, USA, 2012; full map list here).

Many maps may use a combination of different scenario types or may use different scenarios for different zones.