Climate Impacts of The Millennium Eruption of The Changbaishan Volcano

The Millennium Eruption (ME) of Changbaishan Tianchi Volcano is heralded as one of the largest explosive eruptions in the Late Holocene. The geochemistry method estimated that the ME not only produced huge quantities of volcanic debris and lava flows but also emitted up to 45 Tg of sulfur into the atmosphere. The sulfate emissions are higher than the Tambora eruption in 1815 CE, which caused a year without a summer in Europe. Despite such massive emissions, evidence for this eruption's climatic impact in East Asia remains elusive. To explain this contradiction, this study evaluated currently available high-resolution proxy records from the Northern Hemisphere spanning the past two millennia and conducted a volcanic sensitivity experiment using the Community Earth System Model (CESM). Results show that the high-resolution proxy records demonstrate an overall muted negative response during the period of the dating uncertainties, with 945 CE marking the most notable negative anomaly. The sensitivity experiment shows that ME caused significant negative anomalies in both temperatures and precipitation rates in East Asia. Based on the results, we infer that the contradiction between the high Sulfur emissions and a slight glacial sulfate signal may originate from the fact that the ME occurred in 945 CE instead of 946 CE, and the volcanic climatic effects were mitigated by the combined effects of the 945 CE El Niño-like Sea-surface temperatures (SSTs) and the Brewer–Dobson circulation. This study offers a novel perspective on the ME's climatic influence, reconciling previous discrepancies regarding its climatic impact.