Core location
FK17, was drilled during the 2017/2018 austral summer (-70.53648° S, 24.07036° E) 
TIR18, was drilled during the 2018/2019 austral summer (-70.49960° S, 21.88017° E)
We focused our analyses on the top 120 meters of each ice core.

About instruments and precision
The water stable isotopes (d18O and dD) were measured using PICARRO L 2130-i cavity-ring down spectrometer (CRDS) (with sigma = 0.02 ‰ for d18O, 0.2 ‰ for dD and 0.4 ‰ for d-excess). 
Major ions (Na+, K+, Mg+, Ca+, MSA, Cl-, NO3-, SO42-) analysis was performed using a Dionex-ICS5000 liquid chromatography. The standard deviation is 1 ppb for K+, Mg+, Ca+ and MSA, 5 ppb for Na+ and SO42-, 2 ppb for NO3- and 9 ppb for Cl-.
Electrical conductivity measurement (ECM) was performed using the Handheld ECM unit V3, in the cold room at -20°C by applying a direct current (1000 V) on the freshly cleaned surface of the half core. The resulting signal (4 mm resolution) was corrected for temperature and then for porosity as the cores were principally made of snow and firn. As ECM is inversely proportional to air content, the ECM signal was multiplied by the ratio of the ice density to the snow/firn density using the depth-density profile of the corresponding ice core (Kjær et al., 2016).
Density measurements: the core sections were triple weighted/measured to get depth-density profile. The TIR18 cores were directly measured in the field while the FK17 cores were measured as sticks in the home laboratory. For both density profiles, the uncertainty is estimated to be <5 %.

Units
The depths are expressed in meters.
The water stable isotopes (d18O and dD) are expressed in ‰.
The ions concentrations are expressed in ppb.
The ECM is expressed in µA.
The density is expressed in kg/m3.
SMB is expressed in meter ice equivalent (m i.e. a-1).

Sampling resolution
For isotopes and chemistry, the sample resolution is usually 5 cm but may differ in deeper sections due to core conditions. Except for the top parts of the isotope records that are 10 cm and come from the shallow cores drilled to retrieve a complete profile (since there were trenches to drill the main cores).
ECM has a resolution of 4 mm.

Notes
"""NaN"" may indicate a sample not measured or a concentration dismissed because considered as contaminated."
"""n.d."" indicates  a concentration below detection limit."
Calcium concentrations below 3 ppb should be used carefully as they are close to detection limit.
Nitrate (NO3-) concentrations between 2.455 and 9.405 m in the TIR18 record are less accurate as the separation column was old and had to be changed for the deeper section.
In the FK17 isotopes records, there are two sections (101.2175-101.4425 m & 102.13-102.33 m) composed of broken pieces so that the depth and order of these samples are uncertain.
SMB records are presented without and with correction for vertical strain rates.

Summary on the errors (see the companion paper (Physico-chemical properties of the top 120 m of two ice cores in Dronning Maud Land: an open window on spatial and temporal regional variability of environmental proxies - Wauthy et al.) for a complete discussion)
The analytical uncertainty of the depth-density profile is <5 %.
" Uncertainties in the age-depth profile are the “peak-identification uncertainty” and the “peak-date uncertainty”. The “peak-date uncertainty"" in our records is linked to the sampling resolution (5 cm) and the use of multiple seasonal parameters considerably improves the peak-identification."
The age models obtained by manual dating differ from the automatic ones by 0 to 3 years for FK17 and by 0 to 5 years for TIR18 and they mostly lie within the uncertainties of the automatic age models.
Uncertainties on strain rates mainly result from radar measurements and are discussed in the companion paper.