Volcanic sulfate record on Meese/Sowers timescale. Each sample is approximately bi-annual for the last ~12,000 years with a consistent increase in the time covered by each sample to around 50 years/sample at 110,000 years ago. The volcanic sulfate record is derived by applying an empirical orthogonal function (EOF) analysis on the entire glaciochemical time series (Mayewski et al., 1997a). EOF5 was found to explain 12% of the variance in the sulfate record, but it did not significantly explain the variance in any other chemical species. The excellent correlation in the EOF time series and the volcanic sulfate record for the last 9000 years, based on sulfate residuals over a robust spline (Zielinski et al.,1994a) indicates that EOF5 is an indicator of volcanic sulfate deposition over the last 110 kyr.