Triple isotope variations of monthly tap water in China

Tap water isotopic compositions could potentially record information on local climate and water management practices. A new water isotope tracer 17O-excess becomes available in recent years providing additional information of the mechanisms of various hydrological processes. Detailed data records of tap water 17O-excess have not been reported. In this report, monthly tap water samples (n = 652) were collected from December 2014 to November 2015 from 92 sites across China. The isotopic variations (δ2H, δ18O, and δ17O) of tap water were analyzed by a Triple Water Vapor Isotope Analyzer (T-WVIA) based on Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS) technique and two second-order isotopic variables (d-excess and 17O-excess) were calculated. The geographic location information of the 92 collection sites including latitude, longitude, and elevation were also provided in this dataset. This report presents national-scale tap water isotope dataset at monthly time scale. Researchers and water resource managers who focus on the tap water issues could use them to probe the water source and water management strategies at large spatial scales.自来水的同位素组成可潜在反映局地气候与水资源管理活动的相关信息。近年来，新型水同位素示踪剂氧17过剩（17O-excess）的问世，可为各类水文过程的机制解析提供额外的有效信息。目前尚未有关于自来水氧17过剩的详细数据记录被公开报道。 本数据集采集了2014年12月至2015年11月期间，覆盖全国92个采样点的月度自来水样品共652份（n=652）。研究人员采用基于离轴积分腔输出光谱（OA-ICOS）技术的三重水蒸气同位素分析仪（T-WVIA），对所有样品的同位素组成变化（δ²H、δ¹⁸O及δ¹⁷O）进行了分析，并计算得到两个二阶同位素变量：氘过剩值（d-excess）与氧17过剩。 本数据集同时提供了92个采样点的地理区位信息，包括纬度、经度与海拔高度。本数据集为覆盖全国范围的月度尺度自来水同位素数据集。关注自来水相关研究与水资源管理问题的科研人员及管理者，可利用该数据集在大空间尺度上探究水源特征与水资源管理策略。