Methodology:

A suite of chemical species and isotopes was measured using Continuous Flow Analysis (CFA) in the ice core labs at BAS (Cambridge, UK). The CFA system comprises Fast Ion Chromatography (FIC), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), fluorescence, and laser spectroscopy instrumentation. All instruments are customized for operation in continuous mode, that is, ice core sections are melted and analysed simultaneously on the instruments from a continuous sample stream.

The Palmer ice core water-stable isotopes records (d18O, dD) were measured on a laser spectroscopy setup (Picarro, L2130-i). The analyzer operates in continuous mode. A continuous ice-core sample stream is instantaneously evaporated and mixed with a dry carrier gas (N2) in a custom-made evaporation unit prior to being introduced to the analyzer. The raw data were corrected using two-point calibration, utilizing in-house reference waters. The internal standards have been calibrated with the Vienna Standard Mean Ocean Water 2 (V-SMOW2) and Standard Light Antarctic Precipitation 2 (SLAP2) reference waters.

Data collection:

The ice core records were measured in the BAS ice core laboratory. The CFA system comprises Fast Ion Chromatography (FIC), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), fluorescence, and laser spectroscopy instrumentation.

Here we present d18O and dD data from the BAS water-stable isotope laser spectroscopy CFA setup and sodium (23Na), and magnesium (24Mg) from the ICP-MS.

The processing of the data, extraction, assigning depth scale, calibration, and calculation of annual means was done utilizing MATLAB version 2020b.

Data quality:

The raw data were corrected using two-point calibration, utilizing in-house reference waters. The internal standards have been calibrated with the Vienna Standard Mean Ocean Water 2 (V-SMOW2) and Standard Light Antarctic Precipitation 2 (SLAP2) reference waters.