iso2k v0.14.2

Reconstructions of global hydroclimate during the Common Era (CE; the past ~2,000 years) are important for providing context for current and future global environmental change. Stable isotope ratios in water are quantitative indicators of hydroclimate on regional to global scales, and these signals are encoded in a wide range of natural geologic archives. Here we present the Iso2k database, a global compilation of previously published datasets from a variety of natural archives that record the stable oxygen (δ18O) or hydrogen (δ²H) isotopic composition of environmental waters, which reflect hydroclimate changes over the CE. The Iso2k database contains 756 isotope records from the terrestrial and marine realms, including: glacier and ground ice (205); speleothems (68); corals, sclerosponges, and mollusks (145); wood (81); lake sediments and other terrestrial sediments (e.g., loess) (158); and marine sediments (99). Individual datasets have temporal resolutions ranging from sub-annual to centennial, and include chronological data where available. A fundamental feature of the database is its comprehensive metadata, which will assist both experts and non-experts in the interpretation of each record and in data synthesis. Key metadata fields have standardized vocabularies to facilitate comparisons across diverse archives and with climate model simulated fields. This is the first global-scale collection of water isotope proxy records from multiple types of geological and biological archives. It is suitable for evaluating hydroclimate processes through time and space using large-scale synthesis, model-data intercomparison and (paleo)data assimilation.公元纪年（Common Era，CE，即过去约2000年）期间的全球水文气候（hydroclimate）重建成果，可为当前与未来全球环境变化研究提供重要参考背景。水体中的稳定同位素比值（stable isotope ratios）是区域至全球尺度下水文气候的定量指标，此类信号被记录于多种天然地质档案（geologic archives）之中。本文构建了Iso2k数据库，该数据库为全球整合的已发表数据集合集，数据源自各类天然档案，这些档案记录了环境水体的稳定氧（δ¹⁸O）或氢（δ²H）同位素组成，能够反映公元纪年期间的水文气候变化。Iso2k数据库包含来自陆地与海洋领域的756条同位素记录，具体包括：冰川与地下冰（glacier and ground ice，205条；洞穴沉积物（speleothems，68条；珊瑚、硬质海绵（corals, sclerosponges, mollusks，145条；木材（wood，81条；湖泊沉积物及其他陆地沉积物（如黄土，lake sediments and other terrestrial sediments (e.g., loess)，158条；以及海洋沉积物（marine sediments，99条）。各数据集的时间分辨率从亚年际至百年尺度不等，且在可获取的情况下包含年代学数据。该数据库的核心特征之一是其完备的元数据（metadata），可协助专家与非专家群体解读单条记录并开展数据综合研究。关键元数据字段采用标准化词汇表，以促进不同类型档案以及气候模型模拟结果之间的对比。这是首个由多类地质与生物档案来源的全球尺度水体同位素代用记录（proxy records）数据集。该数据库适用于通过大规模综合分析、模型与数据比对（model-data intercomparison）以及（古）数据同化（paleo data assimilation），以探究时空维度上的水文气候过程。