Volcanoes, Climate, and Society

This review examines the societal ramifications of large volcanic eruptions—not the proximal impacts of lava, ash, pumice, and gaseous emissions but rather the consequences of the climate forcing triggered by dispersal of volcanic sulfate aerosol in the stratosphere. Using ice core records of volcanism and tree-ring data of summer temperature anomalies, we analyze 38 preindustrial eruptions that injected an estimated 6 Tg or more of sulfur into the stratosphere. We then explore more than 100 works that consider the volcanism-climate-society nexus, teasing out the key elements of their arguments for or against the role of volcanically forced climate change in far-field societal impacts. As well as summarizing and interrogating the history of ideas and state of the art on this topic, we hope to stimulate further holistic, interdisciplinary approaches to assess the broader implications of volcanic eruptions, particularly for global food security—both in the past and in the future. ▪ There are compelling arguments to consider the role of volcanically forced climate change in explanations of history. ▪ Such research requires integration of geographical, ecological, demographic, econometric, and other data with historical sources and narratives, and therefore demands cross-disciplinary conversation. ▪ Statistical evidence is needed to attribute weather and climate extremes to volcanic forcing, and agricultural and pastoral responses to climate anomalies must be reconstructed at high spatiotemporal resolution. ▪ Several prominent climate forcing eruptions in circa 304, 1182, 1345, and 1453 CE have hitherto received comparatively little attention.