Volcanic lake dynamics and related hazards

The presence of water in volcano craters implies a higher susceptibility to specific, potentially hazardous volcanic events, such as phreatic and phreatomagmatic eruptions, lahars and limnic gas bursts. The driving process behind these hazards is magmatic degassing, inhibited to be released freely to the atmosphere due to a variable degree of physical and chemical decelerating capacity of the lake itself (e.g. selective scrubbing of gases, condensation of vapor, CO2 storage due to hydrostatic loading, bubble absorption along gas rise). This review chapter (1) presents new ideas on hazardous events related to volcanic lakes, (2) presents a revised comprehensive classification scheme, (3) shows how volcanic lakes are perceived by the local populations and cultures (risk perception), (4) revises and proposes mitigation strategies, (5) provides tips on how to ideally interpret precursory signals of such events in a suited, multi-disciplinary monitoring setup, and (6) can become a road map for future volcanic lake research, by posing unanswered questions and proposing working hypotheses.