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Volcanic eruptions impact climate, subtly and profoundly. The size of an eruption is only loosely correlated with the severity of its climate effects, which can include changes in surface temperature, ozone levels, stratospheric dynamics, precipitation, and ocean circulation. We review the processes—in magma chambers, eruption columns, and the oceans, biosphere, and atmosphere—that mediate the climate response to an eruption. A complex relationship between eruption size, style, duration, and the subsequent severity of the climate response emerges. We advocate for a new, consistent metric, the Volcano-Climate Index, to categorize climate response to eruptions independent of eruption properties and spanning the full range of volcanic activity, from brief explosive eruptions to long-lasting flood basalts. A consistent metric for categorizing the climate response to eruptions that differ in size, style, and duration is critical for establishing the relationshipbetween the severity and the frequency of such responses aiding hazard assessments, and furthering understanding of volcanic impacts on climate on timescales of years to millions of years. ▪ We review the processes driving the rocky relationship between eruption size and climate response and propose a Volcano-Climate Index. ▪ Volcanic eruptions perturb Earth's climate on a range of timescales, with key open questions regarding how processes in the magmatic system, eruption column, and atmosphere shape the climate response to volcanism. ▪ A Volcano-Climate Index will provide information on the volcano-climate severity-frequency distribution, analogous to earthquake hazards. ▪ Understanding of the frequency of specific levels of volcanic climate effects will aid hazard assessments, planning, and mitigation of societal impacts.
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Start me up: The relationship between volcanic eruption characteristics and eruption initiation mechanisms
Understanding the processes that initiate volcanic eruptions after periods of quiescence are of paramount importance to interpreting volcano monitoring signals and mitigating volcanic hazards. However, studies of eruption initiation mechanisms are rarely systematically applied to high-risk volcanoes. Studies of erupted materials provide important insight into eruption initiation, as they provide direct insight into the physical and chemical changes that occur in magma reservoirs prior to eruptions, but are also often underutilized. Petrologic and geochemical studies can also constrain the timing of processes involved in eruption initiation, and the time that might be expected to elapse between remote detection of increased activity and eventual eruption. A compilation and analysis of literature data suggests that there are statistical differences in the composition, volume, style and timescales between eruptions initiated by different mechanisms. Knowledge of the processes that initiate eruptions at a given volcano may thus have significant predictive power.
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- PAR ID:
- 10454160
- Date Published:
- Journal Name:
- Volcanica
- Volume:
- 6
- Issue:
- 2
- ISSN:
- 2610-3540
- Page Range / eLocation ID:
- 161 to 172
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.30909/vol.06.02.161172
