Volcanic stratospheric sulfur injections and aerosol optical depth during the Holocene (past 11 500 years) from a bipolar ice-core array

Abstract. The injection of sulfur into the stratosphere by volcanic eruptions is dominant driver natural climate variability on interannual to multidecadal timescales. Based a set continuous sulfate and records from suite ice cores Greenland Antarctica, HolVol v.1.0 database includes estimates magnitudes approximate source latitudes major stratospheric (VSSI) events for Holocene (from 9500 BCE or 11 500 years BP 1900 CE), constituting an extension previous record 7000 years. incorporates new-generation ice-core aerosol with sub-annual temporal resolution demonstrated sub-decadal dating accuracy precision. By tightly aligning stacking WD2014 chronology we resolve long-standing inconsistencies in ancient that arise biased (i.e., dated too old) chronologies over Greenland. We reconstruct total 850 injections excess 1 teragram (Tg S); these eruptions, 329 (39 %) are located low bipolar deposition, 426 (50 Northern Hemisphere extratropics (NHET) 88 (10 Southern (SHET). spatial distribution reconstructed eruption locations agreement prior reconstructions past 2500 In total, injected 7410 Tg S stratosphere: 70 % tropical 25 NH extratropical eruptions. A long-term latitudinally monthly resolved optical depth (SAOD) time series VSSI estimates, representing first Holocene-scale reconstruction constrained Antarctica cores. These new SAOD confirm evidence regional (e.g., Iceland) showing Early (9500–7000 BCE) experienced higher number (+16 cumulative (+86 compared This increase coincides rapid retreat sheets during deglaciation, providing context potential future increases activity regions under projected glacier melting 21st century. data available at https://doi.org/10.1594/PANGAEA.928646 (Sigl et al., 2021).