Nitrate isotopic data from snow collected along the CHICTABA traverse, East Antarctica, 2013-2014

This dataset contains isotopic ratios of nitrate analyzed from snow samples collected along the CHICTABA traverse in East Antarctica in Nov 2013-Jan 2014. Supplemental information on the elevation (doi:10.5194/tc-13-665-2019) and surface mass balance changes (doi:10.5194/tc-13-281-2019) along the traverse route are also included for context. The samples came from relatively shallow depths of the snowpack (maximum = 2.03 m deep) and represent nitrate deposition that occurred from 0-6 years ago. These samples were collected in order to better understand the interaction and mass transfer of nitrate at the snow-air interface in Antarctica, with particular focus on determining the impacts of photolysis on nitrate. Snow samples were collected with three techniques: skin layer samples of the loose snow grains 2-6 mm deep on the snow surface, 1 m depth layer samples taken as a 5-10 cm thick layer from 1 m below the snow surface, and snow pits that extended 99-203 cm deep and were sampled at 3 cm continuous intervals. 250-1500 g of snow were collected into clean plastic bags, melted at room temperature at Concordia Station, Dome C, and then the nitrate was concentrated using an ionic exchange resin. Nitrate concentrations were determined using colorimetry. Isotopic analysis occurred at the Institut des Géosciences de l'Environnement, Grenoble, France, through bacterial denitrification and a MAT 253 mass spectrometer with Gas Bench.