The Law Dome ice core 2000 year dataset collection.

This collection of datasets bring together a coherent set of 2000 years of annually dated ice core records from a compilation of cores drilled at the Dome Summit South (DSS) site at Law Dome, East Antarctica. This version provides improved dating as well as updates and extends some previously released versions to span the time period from -11 to 2017CE.This compilation comprises of records from 4 cores from the DSS site drilled at different times:DSS1617 (66 46'26"S 11248'41"E) drilled on 10/02/2017 using an electromechanical (Eclipse) drill,DSS99 (66 46'14"S 112 48'25"E ) drilled between 20/02/00-06/3/00 with a thermal (Horace) drill,DSS97 (66 46'38"S    112 48'41"E) drilled 28/10/97-26/11/97 with an electromechanical (Eclipse) drill DSSMain (66 46'11"S 112 8'25"E) drilled between the years 1987-1993 using an Istuk electromechanical drill. The dataset download contains four files:DSS_2k_age_horizons.csvThis file contains the depths of each year for the compiled core. Years are primarily determined by the seasonal variations in the annual water stable isotope data.DSS_2k_chemistry_level1.csvThis file contains the per-sample trace chemistry data for each of the analysed ions. This data forms the basis for the annually averaged chemistry datasets as well as the seasonal sea salts.DSS_2k_summer_centred.csvThis file contains annually averaged values for species which peak in winter: nitrate and non-sea-salt sulphate.DSS_2k_winter_centred.csvThis file contains annually averaged values for species which peak in summer: annual accumulation, annual layer thickness, del180, sodium, chloride, magnesium and sulphate as well as the annual values for seasonally averaged (December-March, December-May and June-November) sea salts. For the seasonal average columns, a NaN value indicates that a seasonal average was not calculated.Further details and analysis methods are described in the accompanying data description paper:Jong, L. M., Plummer, C. T., Roberts, J. L., Moy, A. D., Curran, M. A. J., Vance, T. R., Pedro, J., Long, C., Nation, M., Mayewski, P. A., and van Ommen, T. D.: 2000 years of annual ice core data from Law Dome, East Antarctica, Earth Syst. Sci. Data Discuss. [preprint], https://doi.org/10.5194/essd-2021-408, in review, 2022.

本数据集汇编整合了来自东南极劳穹丘（Law Dome）穹顶南位点（Dome Summit South，缩写DSS）的多根钻探冰芯，形成一套连贯的2000年逐年定年冰芯记录集合。本版本优化了定年方案，并对既往发布的多个版本进行了更新与扩展，使得记录时间跨度覆盖公元前11年至公元2017年。

本次汇编包含4根于不同时期在DSS位点钻探的冰芯记录，分别为：DSS1617冰芯：坐标为66°46'26"S，112°48'41"E，于2017年2月10日使用电动机械（Eclipse）钻机钻探完成；DSS99冰芯：坐标为66°46'14"S，112°48'25"E，于2000年2月20日至2000年3月6日间使用热力（Horace）钻机钻探完成；DSS97冰芯：坐标为66°46'38"S，112°48'41"E，于1997年10月28日至1997年11月26日间使用电动机械（Eclipse）钻机钻探完成；DSSMain冰芯：坐标为66°46'11"S，112°8'25"E，于1987年至1993年间使用Istuk电动机械钻机钻探完成。

本次数据集下载包包含4个文件：DSS_2k_age_horizons.csv：该文件记录了汇编冰芯各年份对应的深度数据，年份判定主要依据年际水体稳定同位素的季节变化特征；DSS_2k_chemistry_level1.csv：该文件包含所有分析离子的单样品痕量化学数据，此数据是逐年平均化学数据集以及季节海盐组分的计算基础；DSS_2k_summer_centred.csv：该文件包含冬季浓度峰值组分的逐年平均值，具体为硝酸盐与非海盐硫酸盐；DSS_2k_winter_centred.csv：该文件包含夏季浓度峰值组分的逐年平均值，具体包括年积累量、年冰层厚度、δ¹⁸O、钠、氯、镁与硫酸盐，同时还包含季节平均（12月-3月、12月-5月及6月-11月）海盐组分的年度值。对于季节平均列，NaN值表示未计算该季节平均值。

更多细节与分析方法详见随附的数据说明论文：Jong, L. M.、Plummer, C. T.、Roberts, J. L.、Moy, A. D.、Curran, M. A. J.、Vance, T. R.、Pedro, J.、Long, C.、Nation, M.、Mayewski, P. A. 与van Ommen, T. D.：《东南极劳穹丘2000年逐年冰芯数据》，*Earth Syst. Sci. Data Discuss.* [预印本]，https://doi.org/10.5194/essd-2021-408，2022年，待刊。