Volcanic gases play a large role in the type of eruptions that occur at different volcanoes. Explosive eruptions occur when volcanic gases become trapped, building up pressure within the volcano. Studying the composition of volcanic gases can also help predict the behavior, size, and shape of volcanic plumes after eruptions. Volcanic gases can be “seen” daily at Mount Rainier, bubbling up at the Longmire mineral springs and Ohanapecosh hot springs. #MountRainierVolcano Learn more about how USGS