1988 Aerial view of Mount St. Helens lava dome with rockslide off west crater wall. Photo by Lyn Topinka, March 17, 1988. Yeah, they're pretty dynamic. Actually glaciers are too. Glaciers and volcanoes both.
Volcanoes are warmer.
Oh, whichever one you think is best or a single one that stands out. I can think of a couple. The first was at St. Helens. It was always a bit scary working in the crater in the early days, of course because we were worried about explosive eruptions. Sometimes we felt dozens of earthquakes in a single day which sort of keeps you on edge.