This data set contains sub-annually resolved ice core chemistry data from various sites on the Antarctic Ice Sheet during the US International Trans-Antarctic Scientific Expedition (US ITASE) deployments. Researchers conducted experiments approximately every 30 – 300 km looking for clues representing climatic conditions over the past 200-1000+ years. Ice cores obtained for the glaciochemical component of the US ITASE research were analyzed for soluble major ion content and in some cases trace elements. Extreme events, such as volcanic eruptions, provide absolute age horizons within each core that are easily identified in chemical profiles. The chemical analysis is also useful for quantifying anthropogenic impact, biogeochemical cycling, and for reconstructing past atmospheric circulation patterns.