MBS2023 - The Mount Brown South ice core chronologies and chemistry data

This dataset contains the layer counted annual horizon depths (chronologies) of the Mount Brown South ice cores drilled in 2017/2018 at an elevation of 2,084 metres on the boundary of Princess Elizabeth and Kaiser Wilhelm II Land in East Antarctica (the 'MBS1718 ice cores'). The chronologies were developed using a site-specific annual layer-counting methodology which employed seasonally varying trace chemical species and stable water isotope ratios, combined with alignment to known volcanic horizons. The chronologies include the ‘Main’ 295 m record spanning 1,137 years (873-2009 CE), and three surface cores spanning the most recent 39-52 years up to the surface age at the time of drilling (austral summer 2017/2018). The MBS chronologies presented here are collectively named 'MBS2023' to differentiate them from any possible future changes to the age-by-depth scales, which would result in a new and different chronology. MBS2023 is synchronized to the WAIS Divide ice core chronology, 'WD2014'. In addition this dataset includes the trace impurities data for the 'Main' and surface ice core records, on a depth scale and with annual horizon dates from MBS2023. Note that the within year dates are calculated assuming uniform annual accumulation, and thus should be interpreted as estimates based on this assumption. See Crockart et al., 2021 and Jackson et al., 2023 for more information on the variability inherent in the annual snowfall accumulation regime at Mount Brown South: https://cp.copernicus.org/articles/17/1795/2021/cp-17-1795-2021.pdf and https://cp.copernicus.org/articles/19/1653/2023/. A full description of the age scales, datasets and the development of the chronologies is detailed in Vance et al. (2024), 'An annually resolved chronology for the Mount Brown South ice cores, East Antarctica', at https://cp.copernicus.org/articles/20/969/2024/cp-20-969-2024.pdf.The stable water isotope datasets associated with the 'MBS1718 ice cores' are available separately. The 'Main' isotope dataset can be found here: "An 1135 year very high-resolution water isotope record of polar precipitation from the Indo-Pacific sector of East Antarctica", described by the doi:10.26179/ygeq-1a95, and the surface core dataset can be found here: "The Mount Brown South surface core (MBS1718 'Alpha', 'Bravo', and 'Charlie') chronologies and stable water isotope records" described by the doi:10.26179/372t-4q89

本数据集收录了2017/2018年于东南极洲伊丽莎白公主地与威廉二世地交界地带、海拔2084米处钻取的布朗南山冰芯（下称"MBS1718冰芯"）的年层计数深度年代序列（chronologies）。该年代学序列采用站点专属年层计数方法构建，结合了季节变化的痕量化学组分与稳定水同位素比值，并匹配已知火山层位。年代学序列包含一条长295米的"主记录"，覆盖1137年（公元873年至2009年），另有三根表层冰芯，覆盖截至钻探时（2017/2018年南极夏季）表层年龄的最近39至52年。本次发布的MBS年代学序列统一命名为"MBS2023"，以区分未来可能更新的深度-年龄标尺（此类更新将生成新的、不同的年代学序列）。MBS2023已与WAIS Divide冰芯年代学序列"WD2014"完成同步校准。此外，本数据集还包含基于MBS2023年层日期与深度标尺的"主记录"及表层冰芯的痕量杂质数据。需注意，年内日期是假设年积雪积累量均匀分布计算得到的，因此仅为基于该假设的估算值。有关布朗南山地区年降雪积累格局的固有变异性，详见Crockart等人2021年与Jackson等人2023年的研究：https://cp.copernicus.org/articles/17/1795/2021/cp-17-1795-2021.pdf 及 https://cp.copernicus.org/articles/19/1653/2023/。有关年龄标尺、数据集及年代学序列构建的完整说明，详见Vance等人2024年发表的《东南极洲布朗南山冰芯年分辨率年代学》，链接为：https://cp.copernicus.org/articles/20/969/2024/cp-20-969-2024.pdf。与"MBS1718冰芯"相关的稳定水同位素数据集可单独获取。其中"主记录"同位素数据集可通过DOI:10.26179/ygeq-1a95对应的论文《东南极洲印度-太平洋扇区极地降水的1135年极高分辨率水同位素记录》获取，表层冰芯同位素数据集则可通过DOI:10.26179/372t-4q89对应的论文《布朗南山表层冰芯（MBS1718"Alpha""Bravo"及"Charlie"）年代学与稳定水同位素记录》获取。