Skip to content

The compounding climate impact of the 5.6ky BCE eruption of Mount Mazama

^^Evelien JC van Dijk^1^, Felix Riede2, Claudia Timmreck3, Kirstin Krüger1, and Michael Sigl4

  • Affiliations:  1Department of Geosciences, University of Oslo, Oslo, Norway; 2Department of Archaeology and Heritage Studies, Aarhus University, Aarhus, Denmark; 3Max Planck Institute for Meteorology, Hamburg, Germany; 4Department of Physics and the Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland 

  • Presentation type: Poster

  • Presentation time: Monday 16:30 - 18:30, Room Poster Hall

  • Poster Board Number: 6

  • Programme No: 6.1.12

  • Theme 6 > Session 1

Abstract

The Mount Mazama (Crater Lake, U.S.A.) eruption counts among the largest eruptions of the Holocene, yet its impact on contemporaneous climate, environment, and humans remains uncertain. Here, we use Earth System Model simulations to provide an improved understanding of the potential impacts of this cataclysmic eruption on global climate, and we relate this to societal impacts. The model simulations produce severe and diverging temperature and precipitation anomalies in different regions of the world. We argue that the compound occurrences of severe cooling and precipitation extremes likely had a significant impact on the agrarian, pastoralist, and foraging societies living in these regions, with crop failures due to drought and pronounced flooding in areas with extreme precipitation increase. Our study illustrates how large volcanic eruptions can alter surface climate, with varying and contrasting compound climate anomalies covering much of the land surface. A volcanic event like the Mount Mazama eruption while rare can also occur in the next decades or centuries. In the present, an eruption of this magnitude has considerable potential for multiple critical infrastructure and breadbasket failures, impacting food security, lives, and livelihoods around the world. Studying these very large past eruptions is thus imperative for better understanding the nature of and risks associated with low-likelihood, high-impact events -- events that global society is patently ill-prepared for.