Impact of volcanic eruptions on extratropical atmospheric circulations: review, revisit and future directions

Understanding the impacts of volcanic eruptions on the atmospheric circulations and surface climate in the extratropics is important for inter-annual to decadal climate prediction. Previous studies on the Northern Hemisphere climate responses to volcanic eruptions have shown that volcanic eruptions likely induce northern Eurasian warming through the intensified Arctic polar vortex in the stratosphere and the positive phase of Arctic Oscillation/North Atlantic Oscillation in the troposphere. However, large uncertainties remain and the detailed physical processes have yet to be determined. The circulation responses in the Southern Hemisphere also remain controversial with large differences between the observed and model-simulated results. In this paper, we review previous studies on the extratropical circulation and surface climate responses to volcanic eruptions and update our understanding by examining the latest observational datasets and climate model simulations. We also propose new insights into the crucial role of the latitude of volcanic eruptions in determining the extratropical circulation changes, which has received less attention. Finally, we discuss uncertainty factors that may have important implications to the extratropical circulation responses to volcanic eruptions and suggest future directions to resolve those issues through systematic model experiments.

Automated summary

Understanding the impacts of volcanic eruptions on atmospheric circulations and surface climate is crucial for climate prediction. Previous studies have shown that volcanic eruptions can induce warming in the Northern Hemisphere through certain circulation patterns, but uncertainties and controversies remain. This paper reviews previous studies, updates our understanding using new observations and model simulations, and proposes new insights into the role of volcanic eruption latitude. It also discusses uncertainty factors and suggests future research directions to resolve these issues.