100km-scale isotopic (d18O, dD) variability of the top-meter between B31 and Kohnen, Dronning Maud Land (R samples)

Isotopic composition of the top-meter of the snowpack along a 115km traverse between B31 and D50, near Kohnen station, Dronning-Maud Land, East-Antarctica. Site D2 refers to the firn core drilling site B31. At each sampling site, profiles were sampled at 10 m distance in 90 m long trenches:_R samples using the dual-tube sampling technique (Dallmayr et al., 2020), 3 subsections of the top-1m were sampled and at sites C4, C5, D2, D7, D24, D38, the top-1m of the trenches were sampled with the dual-tube and 5 single liners were taken and subsampled to 1 - 3 cm resolution (Hirsch, Nora; Hörhold, Maria; Dallmayr, Remi; Laepple, Thomas; Freitag, Johannes; Meyer, Hanno; Weiner, Mikaela (2023): Stable water isotopologues of arrays of high resolution 1 m snow cores from across Dronning Maud Land, East Antarctic Plateau [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.956273)_M samples: Mixed 4 subsections of the top-1.2m of the 90m long trenches excavated by Pistenbully. All isotopic analysis were realized by CRDS (Cavity-Ring-Down Spectroscopy) measurements at the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung in Bremerhaven (instrument models L-2120-i, L-2140-i, Picarro Inc.). The samples were shipped frozen to the Alfred-Wegener-Institut and stored at -25°C. Prior to measurements the samples were melted in the sample bags at room temperature. The measurement set-up followed the Van-Geldern Protocol. Each sample was injected four times and the standard deviation is computed.

南极东部毛德皇后地（Dronning-Maud Land）科嫩站（Kohnen station）附近，B31与D50之间115千米科考断面的积雪表层（0~1米）同位素组成。其中D2点位对应粒雪芯钻取点位B31。
在每个采样点位，于90米长探槽内每隔10米采集剖面样品：
R类样品：采用双管采样技术（Dallmayr等人，2020）采集积雪表层0~1米的3个分段；在C4、C5、D2、D7、D24、D38点位，采用双管法采集探槽表层0~1米积雪，并取出5个单衬管样品，细分至1~3厘米的分辨率（Hirsch, Nora; Hörhold, Maria; Dallmayr, Remi; Laepple, Thomas; Freitag, Johannes; Meyer, Hanno; Weiner, Mikaela (2023): 东南极高原毛德皇后地全域高分辨率1米雪芯阵列的稳定水同位素异构体数据集[数据集]. PANGAEA, https://doi.org/10.1594/PANGAEA.956273）
M类样品：将Pistenbully履带式雪地车挖掘的90米长探槽表层0~1.2米的4个分段混合而成。
所有同位素分析均在不来梅港的阿尔弗雷德·魏格纳研究所·亥姆霍兹极地与海洋研究中心（Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung）通过CRDS（光腔衰荡光谱法，Cavity-Ring-Down Spectroscopy）完成，使用的仪器型号为L-2120-i、L-2140-i（Picarro Inc.）。
样品以冷冻状态运至该研究所，并于-25℃下保存。分析前，将样品置于样品袋中于室温下融化。测量流程遵循Van-Geldern规程（Van-Geldern Protocol）。每个样品进样四次，并计算其标准偏差。