黑河流域地表过程综合观测网（混合林站涡动相关仪-2024）

该数据集包含了2024年1月1日至2024年12月31日的黑河流域地表过程综合观测网下游混合林站涡动相关仪观测数据。站点位于内蒙古额济纳旗四道桥，下垫面是胡杨与柽柳。观测点的经纬度是101.1335E，41.9903N，海拔874 m。涡动相关仪的架高22m，采样频率是10Hz，超声朝向是正北向，超声风速温度仪（CSAT3B）与CO2/H2O分析仪（Li7500DS）之间的距离是17cm。
涡动相关仪的原始观测数据为10Hz，发布的数据是采用Eddypro软件处理的30分钟数据，其处理的主要步骤包括：野点值剔除，延迟时间校正，坐标旋转（二次坐标旋转），频率响应修正，超声虚温修正和密度（WPL）修正等。同时对各通量值进行质量评价，主要是大气平稳性（Δst）和湍流相似性特征（ITC）的检验。对Eddypro软件输出的30min通量值也进行了筛选：（1）剔除仪器出错时的数据；（2）剔除降水前后1h的数据；（3）剔除10Hz原始数据中每30min内缺失率大于10%的数据。观测数据的平均周期为30分钟，一天48个数据，缺失数据标记为-9999。冬季水汽密度出现一些负值，进行了剔除。
发布的观测数据包括：日期/时间Date/Time，风向Wdir（°），水平风速Wnd（m/s），侧向风速标准差Std_Uy（m/s），超声虚温Tv（℃），水汽密度H2O（g/m3），二氧化碳浓度CO2（mg/m3），摩擦速度Ustar（m/s），奥布霍夫长度L（m），感热通量Hs（W/m2），潜热通量LE（W/m2），二氧化碳通量Fc（mg/（m2s）），感热通量的质量标识QA_Hs，潜热通量的质量标识QA_LE，二氧化碳通量的质量标识QA_Fc。感热、潜热、二氧化碳通量的质量标识分为九级（质量标识1-3数据质量好，4-6数据质量较好，7-8数据质量较差（较插补数据好）；9数据质量差））。数据时间的含义，如0:30代表0:00-0:30的平均；数据以*.xls格式存储。
黑河流域地表过程综合观测网或站点信息请参考Liu et al. (2018)和Liu et al. (2023)。

This dataset contains eddy covariance system observation data from the Mixed Forest Station in the lower reaches of the Heihe River Basin Surface Process Comprehensive Observation Network, covering the period from January 1, 2024 to December 31, 2024. The station is located at Sidaoqiao, Ejina Banner, Inner Mongolia, with its underlying surface dominated by Populus euphratica and Tamarix ramosissima. The geographic coordinates of the observation point are 101.1335°E, 41.9903°N, and the elevation is 874 m. The eddy covariance system is installed at a height of 22 m, with a sampling frequency of 10 Hz. The ultrasonic anemometer faces true north, and the distance between the ultrasonic anemometer/thermometer (CSAT3B) and the CO2/H2O analyzer (Li7500DS) is 17 cm.

The original observation data of the eddy covariance system is at 10 Hz. The released data are 30-minute averaged data processed using EddyPro software. The main processing steps include: outlier removal, time lag correction, double coordinate rotation, frequency response correction, ultrasonic virtual temperature correction, and density (WPL) correction, etc. Meanwhile, quality assessment was conducted for each flux value, mainly including tests of atmospheric stationarity (Δst) and turbulence similarity characteristics (ITC). The 30-minute flux values output by EddyPro were further screened based on the following criteria: (1) Remove data collected during instrument malfunctions; (2) Remove data within 1 hour before and after precipitation events; (3) Remove data with a missing rate greater than 10% in the 10 Hz original data per 30-minute interval. The average period of the observation data is 30 minutes, resulting in 48 data records per day. Missing data are marked as -9999. Some negative values of water vapor density observed in winter were removed.

The released observation data include: Date/Time, wind direction Wdir (°), horizontal wind speed Wnd (m/s), lateral wind speed standard deviation Std_Uy (m/s), ultrasonic virtual temperature Tv (℃), water vapor density H2O (g/m³), carbon dioxide concentration CO2 (mg/m³), friction velocity Ustar (m/s), Obukhov length L (m), sensible heat flux Hs (W/m²), latent heat flux LE (W/m²), carbon dioxide flux Fc (mg/(m²s)), quality flag of sensible heat flux QA_Hs, quality flag of latent heat flux QA_LE, and quality flag of carbon dioxide flux QA_Fc. The quality flags for sensible heat, latent heat, and carbon dioxide fluxes are graded into nine levels: data with quality flags 1–3 are of good quality, 4–6 are of relatively good quality, 7–8 are of poor quality (better than interpolated data), and 9 is of poor quality. The meaning of the data timestamp: for example, 0:30 represents the average over the period 0:00–0:30. The data are stored in *.xls format.

For information regarding the Heihe River Basin Surface Process Comprehensive Observation Network or its stations, please refer to Liu et al. (2018) and Liu et al. (2023).

搜集汇总

背景与挑战

背景概述

该数据集包含2024年黑河流域下游混合林站的涡动相关仪观测数据，时间分辨率为30分钟，覆盖全年。数据采集于内蒙古额济纳旗四道桥的胡杨与柽柳下垫面，包括风向、风速、温度、水汽密度、二氧化碳浓度及感热、潜热和二氧化碳通量等多个变量，并经过严格的质控处理，适用于水文和陆地表层过程研究。