Soil data at station Samoylov (2021)@en

Understanding permafrost processes and changes requires long-term observational datasets. This dataset is a continuation of the dataset available from the long-term observational site Samoylov, located in the Lena River Delta, Siberia (72.37°N, 126.48°E). The location is characterized by a cold, dry tundra climate with mean annual air temperature of -11.7°C (using years with complete data between 1998 and 2017). The monthly mean temperatures over this period varied between 9.4°C in the warmest month (July) and -31.7°C in the coldest month (February). The average summer rainfall (June-October) was 145.2 mm. This dataset adds recent years to the observations of meteorological parameters, energy balance, and subsurface observations which have been recorded since 1998. The instrumentation, calibration, processing and data quality control is explained in Boike et al. (2019). The data provide observations of temporally variable parameters that mitigate energy fluxes between permafrost and atmosphere, such as ground heat flux, active layer and permafrost temperature, soil volumetric water content, relative permittivity, and soil bulk electrical conductivity. Those variables were measured at various depths and beneath different microtopographic features (a polygon center, a rim, a slope, and a trough), representing landscape heterogeneity. The observations are suitable for use in integrating, calibrating and testing permafrost as a component in Earth System Models. The resulting quality-controlled dataset is unique in the Arctic and serves as a baseline for future studies.深入理解多年冻土（permafrost）的过程与变化，亟需长期观测数据集的支撑。本数据集是坐落于西伯利亚勒拿河三角洲（72.37°N，126.48°E）的萨莫伊洛夫（Samoylov）长期观测站原有数据集的延续。该观测站地处寒冷干燥的苔原（tundra）气候区，1998至2017年完整观测时段内的年平均气温为-11.7℃。该时段内的月均气温波动范围为最暖月7月的9.4℃至最冷月2月的-31.7℃。夏季（6月至10月）平均降雨量为145.2毫米。本数据集在1998年起记录的气象参数、能量平衡及地下观测数据基础上，补充了近年的观测结果。仪器布设、校准方法、数据处理流程及质量控制方案详见Boike等人2019年的研究成果。本数据集记录了调控多年冻土与大气间能量通量交换的时序变化参数，具体包括土壤热通量、活动层（active layer）与多年冻土温度、土壤体积含水量、相对介电常数及土壤体积电导率等。上述变量在不同深度以及不同微地形（包括多边形中心、边缘、坡地与洼地）下开展观测，以反映景观异质性。该观测数据可用于整合、校准与验证作为地球系统模型（Earth System Models）组分的多年冻土模块。这套经过质量控制的数据集在北极地区具有独特性，可作为未来相关研究的基准参考。