Ice core chemistry database: an Antarctic compilation of sodium and sulfate records spanning the past 2000 years

Changes in sea ice conditions and atmospheric circulation over the Southern Ocean play an important role in modulating Antarctic climate. However, observations of both sea ice and wind conditions are limited in Antarctica and the Southern Ocean, both temporally and spatially, prior to the satellite era (1970 onwards). Ice core chemistry data can be used to reconstruct changes over annual, decadal, and millennial timescales. To facilitate sea ice and wind reconstructions, the CLIVASH2k (CLimate Variability in Antarctica and the Southern Hemisphere over the past 2000 years) working group has compiled a database of two species, sodium [Na+] and sulfate [SO42-], commonly measured ionic species. The database (; Thomas et al., 2022) comprises records from 105 Antarctic ice cores, containing records with a maximum age duration of 2000 years. An initial filter has been applied, based on evaluation against sea ice concentration, geopotential height (500 hPa), and surface wind fields to identify sites suitable for reconstructing past sea ice conditions, wind strength, or atmospheric circulation.

Automated summary

Changes in sea ice and atmospheric circulation in the Southern Ocean are crucial factors in shaping Antarctic climate. Limited historical data exists prior to 1970, but ice core chemistry can be used to reconstruct long-term changes. The CLIVASH2k working group compiled a database of sodium and sulfate ions from 105 Antarctic ice cores spanning 2000 years. Sites suitable for reconstructing past sea ice conditions, wind strength, or atmospheric circulation were identified through filters based on sea ice concentration, geopotential height, and surface wind fields.