HiWATER: Dataset of hydrometeorological observation network (eddy covariance system of Populus forest station, 2015)

This data set contains the eddy correlativity observation data of the euphrate poplar forest station downstream of heihe hydrometeorological observation network from January 1, 2015 to December 31, 2015.The station is located in Inner Mongolia ejin banner four bridge, under the surface is the euphorbia poplar forest.The longitude and latitude of the observation point are 101.1236e, 41.9928n and 876m above sea level.The rack height of the vortex correlativity instrument is 22m, the sampling frequency is 10Hz, the ultrasonic orientation is due north, and the distance between the ultrasonic wind speed and temperature meter (CSAT3) and CO2/H2O analyzer (Li7500) is 17cm.The original observation data of the vortex correlativity instrument is 10Hz, and the published data is the 30-minute data processed by Eddypro software. The main processing steps include: outliers, delay time correction, coordinate rotation (quadratic coordinate rotation), frequency response correction, ultrasonic virtual temperature correction and density (WPL) correction.Quality assessment for each intercompared to at the same time, mainly is the atmospheric stability (Δ st) and turbulent characteristics of similarity (ITC) test.The 30min pass value output by Eddypro software was also screened :(1) data when instrument error was eliminated;(2) data of 1h before and after precipitation are excluded;(3) remove the data with a missing rate of more than 10% in the original 10Hz data within every 30 minutes;(4) the observation data of weak turbulence at night (u* less than 0.2m/s) were excluded.The average observation period was 30 minutes, 48 data per day, and the missing data was marked as -6999.Suspicious data caused by instrument drift, etc., shall be marked in red font.On April 22, solstice and April 25, data was missing due to the calibration of the vortex system Li7500.August 17 solstice September 5, due to memory card problems, resulting in intermittent data.The published observational data include:Date/Time for the Date/Time, wind Wdir (°), Wnd horizontal wind speed (m/s), standard deviation Std_Uy lateral wind speed (m/s), ultrasonic virtual temperature Tv (℃), the water vapor density H2O (g/m3), carbon dioxide concentration CO2 (mg/m3), friction velocity Ustar) (m/s), Mr. Hoff length L (m), sensible heat flux Hs (W/m2), latent heat flux LE (W/m2), carbon dioxide flux Fc (mg/(m2s)), the quality of the sensible heat flux identifier QA_Hs, the quality of the latent heat flux identifier QA_LE,Quality indicator for co2 flux QA_Fc.The quality of the sensible heat and latent heat, carbon dioxide flux identification is divided into three (quality id 0: (Δ st < 30, the ITC < 30);1: (Δ st < 100, ITC < 100);The rest is 2).The meaning of data time, such as 0:30 represents the average of 0:00-0:30;The data is stored in *.xls format.For information of hydrometeorological network or station, please refer to Li et al. (2013), and for observation data processing, please refer to Liu et al. (2011).

本数据集收录了自2015年1月1日至2015年12月31日，位于黑河水文气象观测网络下游的疏勒河流域胡杨林观测站所采集的涡度相关观测数据。观测站坐落于内蒙古自治区额济纳旗四桥，地表覆盖为梭梭胡杨林。观测点的经纬度分别为101.1236E，41.9928N，海拔高度为876米。涡度相关仪的支架高度为22米，采样频率为10Hz，超声波方向指向正北，超声波风速与温度计（CSAT3）及二氧化碳/水汽分析仪（Li7500）之间的距离为17厘米。涡度相关仪的原始观测数据频率为10Hz，发布的数据为经过Eddypro软件处理的30分钟数据。主要处理步骤包括：异常值处理、延迟时间校正、坐标旋转（二次坐标旋转）、频率响应校正、超声波虚拟温度校正及密度（WPL）校正。对每次相互比较的数据进行质量评估，主要涉及大气稳定性（Δst）和湍流相似性（ITC）测试。Eddypro软件输出的30分钟通行值经过筛选：（1）消除仪器误差的数据；（2）排除降水前后1小时内的数据；（3）移除每30分钟内原始10Hz数据中缺失率超过10%的数据；（4）排除夜间弱湍流（u*小于0.2m/s）的观测数据。平均观测周期为30分钟，每日48个数据点，缺失数据以-6999标记。由仪器漂移等引起的可疑数据将以红色字体标注。由于涡度系统Li7500校准，4月22日和4月25日数据缺失。8月17日夏至至9月5日，由于存储卡问题，导致数据间歇性缺失。发布的数据包括：日期/时间、风向（°）、水平风速（m/s）、横向风速标准差Std_Uy（m/s）、超声波虚拟温度Tv（℃）、水汽密度H2O（g/m3）、二氧化碳浓度CO2（mg/m3）、摩擦速度Ustar（m/s）、Hoff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)）、感热通量标识符QA_Hs、潜热通量标识符QA_LE、二氧化碳通量质量指标QA_Fc。感热和潜热、二氧化碳通量的标识质量分为三级（质量标识ID 0：（Δst < 30，ITC < 30）；1：（Δst < 100，ITC < 100）；其余为2）。数据时间意义，如0:30表示0:00-0:30的平均值；数据存储为*.xls格式。有关水文气象网络或站点的信息，请参阅Li等（2013）的研究，关于观测数据处理，请参阅Liu等（2011）的研究。