This data set is part of the West Antarctic Ice Sheet Cores (WAISCORES) project, an NSF-funded project to understand the influence of the West Antarctic Ice Sheet on climate and sea level change. WAISCORES researchers acquired and analyzed snow pit and core samples from the Siple Dome, in the Siple Coast region, West Antarctica. This data set includes glaciochemical spatial variability data for six Siple Dome snow pits. Samples involved measuring hydrogen peroxide (H2O2) and formaldehyde (HCHO) in the air, snow, firn, and ice via suppressed ion chromatography. The data can be used to interpret changes in concentrations of these species recorded in ice cores. Data in this collection were obtained during two Antarctic field seasons in 1994 to 1995 and 1996 to 1997. Data are available via FTP in tab-delimited ASCII text (.dat, .txt) file format.