REGIONAL CLIMATIC IMPACTS FROM LARGE EXPLOSIVE ERUPTIONS DURING THE LAST 2000 YEARS

Regional climate responds in a complex fashion to aerosol loading from large-scale explosive volcanic eruptions even though the general impact for these events is typically a global average cooling. The latitude of the eruption may be key as it can influence the extent to which the equator to pole stratospheric temperature gradient is perturbed. Such perturbations can cause enhancements of large-scale circulation patterns such as the polar vortex, which can translate to varying extents of warming or cooling on a regional level. Regional climate reconstructions for areas in China, East Asia, Europe, Western North America, and South America show that there have been significant periods of regional warming and cooling due to volcanic eruptions. A database has been constructed with estimates of magma discharge and sulfur dioxide yield for fifteen of the largest volcanic eruptions during the last 2000 years (VEI >6). Regional climate data and climate reconstructions using various temperature proxies have been evaluated in the context of the inferred aerosol loadings from these large eruptions to explore the influence of total sulfur aerosol discharge, latitude, and seasonality on cooling and warming trends following eruptions that produce significant stratospheric influxes of climate modifying gases and particles.