Annual-resolved sulfur and non-sea-salt sulfur concentrations and inferred volcanic sulfate deposition rates from six Greenland ice cores, 699-1002 CE

Annual-resolved sulfur and non-sea-salt sulfur concentrations and inferred volcanic sulfate deposition rates from the six ice cores NEEM-2011-S1 (Sigl et al., 2013), NGRIP1 (Plummer et al., 2012), NGRIP2 (McConnell et al., 2018), TUNU2013 (Sigl et al., 2015) and B19 between 699 and 1001 CE.