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

• Published in: Earth System Science Data
• Main Authors: Sigl, Michael, Toohey, Matthew, McConnell, Joseph R., Cole-Dai, Jihong, Severi, Mirko
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2022
• Subjects: 530 Physics; 540 Chemistry; 550 Earth sciences & geology; Greenland; Antarc*; Antarctica; ice core; Iceland
• Online Access: https://boris.unibe.ch/171247/1/Pub_THERA_19_Sigl2022_ESSD.pdf; https://boris.unibe.ch/171247/

The injection of sulfur into the stratosphere by volcanic eruptions is the dominant driver of natural climate variability on interannual-to-multidecadal timescales. Based on a set of continuous sulfate and sulfur records from a suite of ice cores from Greenland and Antarctica, the HolVol v.1.0 database includes estimates of the magnitudes and approximate source latitudes of major volcanic stratospheric sulfur injection (VSSI) events for the Holocene (from 9500 BCE or 11,500 year BP to 1900 CE), constituting an extension of the previous record by 7,000 years. The database incorporates new-generation ice-core aerosol records with sub-annual temporal resolution and demonstrated sub-decadal dating accuracy and precision. By tightly aligning and stacking the ice-core records on the WD2014 chronology from Antarctica we resolve long-standing inconsistencies in the dating of ancient volcanic eruptions that arise from biased (i.e., dated too old) ice-core chronologies over the Holocene for Greenland. We reconstruct a total of 850 volcanic eruptions with injections in excess of 1 TgS, of which 329 (39%) are located in the low latitudes with bipolar sulfate deposition, 426 (50%) are located in the Northern Hemisphere (NH) extratropics and 88 (10%) are located in the Southern Hemisphere (SH) extratropics. The spatial distribution of reconstructed eruption locations is in agreement with prior reconstructions for the past 2,500 years. In total, these eruptions injected 7410 teragram of sulfur (TgS) into the stratosphere, 70% from tropical eruptions and 25% from NH extratropical eruptions. A long-term latitudinally and monthly resolved stratospheric aerosol optical depth (SAOD) time series is reconstructed from the HolVol VSSI estimates, representing the first Holocene-scale reconstruction constrained by Greenland and Antarctica ice cores. These new long-term reconstructions of past VSSI and SAOD variability confirm evidence from regional volcanic eruption chronologies (e.g., from Iceland) in showing that the early Holocene ...