Historical eruptions typically have produced lahars, lava flows, and ashfalls.
It's estimated that it can only take 30% water to initiate ash into a lahar.
This is the same mechanism that caused the 1953 lahar.
The lahars had left behind a gray mass which covered the entire town.
Lava flows could sometimes melt down ice and glaciers that accumulated on the volcano's crater, creating massive lahar flows.
This meltwater mix means that subglacial eruptions often generate dangerous jkulhlaups (floods) and lahars.
Because of this, computer programs would be able to identify the approaching information and activate an automatic notice when a large lahar is identified.
Lahars have the consistency, viscosity and approximate density of concrete: fluid when moving, solid at rest.
