黑河生态水文遥感试验：水文气象观测网数据集（下游四道桥超级站大孔径闪烁仪-2015）

该数据集包含了黑河水文气象观测网下游四道桥站的大孔径闪烁仪通量观测数据。两组LAS（BLS900_1和BLS900_2）沿东北—西南方向，有效高度为25.5m，光径长度分别是2390m和2380m，观测时间分别为2015年1月1日至4月24日和2015年2月11日至12月31日。2015年4月25日调整为一组LAS（BLS900-1拆除，BLS900-2放置在原BLS900_1发射塔和BLS900_2接收塔），有效高度为25.5m，光径长度为2350m。站点位于内蒙古额济纳旗，下垫面是柽柳、胡杨、裸地和耕地。1号点北塔的经纬度是101.147E，42.005N，南塔的经纬度是101.131E，41.987N；2号点北塔的经纬度是101.137E，42.008N，南塔的经纬度是101.121E，41.990N，海拔高度约为873m。大孔径闪烁仪的采样频率都是1min。
大孔径闪烁仪原始观测数据为1min，发布的数据为经过处理与质量控制后的数据，其中感热通量主要是结合自动气象站观测数据，基于莫宁-奥布霍夫相似理论通过迭代计算得到，主要的质量控制步骤包括：（1）剔除Cn2达到饱和的数据（BLS900_1：Cn2 >7.25E-14， BLS900_2：Cn2 >7.33 E-14，调整后BLS900：Cn2 >7.58E-14）；（2）剔除解调信号强度较弱的数据（Average X Intensity<1000）；（3）剔除降水时刻的数据；（4）剔除稳定条件下的弱湍流的数据（u*小于0.1m/s）。在迭代计算过程中，选取Thiermann and Grassl(1992)的稳定度普适函数。详细介绍请参考Liu et al(2011, 2013)。
关于发布数据的几点说明：（1）两台LAS同时观测期间，下游1号点LAS数据以BLS900_1为主，缺失时刻由-6999标记；下游2号点LAS数据以BLS900_2为主，缺失时刻由-6999标记。4月25日后，下游LAS数据为BLS900_2观测，缺失时刻由-6999标记。（2）数据表头：Date/Time ：日期/时间（格式：yyyy/m/d h:mm），Cn2 ：空气折射指数结构参数（单位：m-2/3），H_LAS ：感热通量（单位：W/m2）。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。
水文气象网或站点信息请参考Li et al. (2013)，观测数据处理请参考Liu et al. (2011)。

This dataset contains large aperture scintillometer (LAS) flux observation data from the Sidaoqiao Station in the lower reaches of the Heihe Hydrometeorological Observation Network. Two sets of LAS (BLS900_1 and BLS900_2) were deployed along the northeast-southwest direction, with an effective height of 25.5 m, and their optical path lengths were 2390 m and 2380 m respectively. Their observation periods were from January 1 to April 24, 2015, and from February 11 to December 31, 2015, respectively. On April 25, 2015, the observation system was adjusted to use one set of LAS: BLS900_1 was dismantled, and BLS900_2 was relocated to the original transmitter tower of BLS900_1 and the receiver tower of BLS900_2, with an effective height of 25.5 m and an optical path length of 2350 m.

The station is located in Ejina Banner, Inner Mongolia, with underlying surfaces including tamarisk, Populus euphratica, bare land and cultivated land. The coordinates of the north tower at Site 1 are 101.147°E, 42.005°N, and those of the south tower are 101.131°E, 41.987°N; the coordinates of the north tower at Site 2 are 101.137°E, 42.008°N, and those of the south tower are 101.121°E, 41.990°N, with an altitude of approximately 873 m. The sampling frequency of all LAS systems is 1 minute.

The original observation data of the LAS has a 1-minute time resolution. The released data are processed and quality-controlled. The sensible heat flux is mainly calculated iteratively based on the Monin-Obukhov similarity theory, combined with observations from automatic weather stations. The main quality control steps include: (1) Removing data with saturated Cn2 values: BLS900_1: Cn2 > 7.25E-14; BLS900_2: Cn2 > 7.33E-14; adjusted LAS system: Cn2 > 7.58E-14; (2) Removing data with weak demodulated signal strength (Average X Intensity < 1000); (3) Removing data collected during precipitation events; (4) Removing data with weak turbulence under stable conditions (u* < 0.1 m/s). The stability universal function proposed by Thiermann and Grassl (1992) was selected during the iterative calculation process. For detailed information, please refer to Liu et al. (2011, 2013).

Notes on the released data: (1) During the period when both LAS units were operating simultaneously, the LAS data at the lower reaches Site 1 is primarily from BLS900_1, with missing values marked as -6999; the LAS data at Site 2 is primarily from BLS900_2, with missing values marked as -6999. After April 25, 2015, the LAS data at the lower reaches is from BLS900_2, with missing values marked as -6999. (2) Table headers: Date/Time: Date/time (format: yyyy/m/d h:mm), Cn2: Atmospheric refractive index structure parameter (unit: m^-2/3), H_LAS: Sensible heat flux (unit: W/m²). The meaning of the data time stamp: for example, 0:30 represents the average value of the 0:00-0:30 period; the data is stored in *.xls format.

For information on the hydrometeorological network or stations, please refer to Li et al. (2013); for data processing methods, please refer to Liu et al. (2011).

搜集汇总

背景与挑战

背景概述

该数据集是2015年黑河下游四道桥超级站的大孔径闪烁仪观测数据，用于测量感热通量等水文气象参数，覆盖全年两个时间段，并经过严格的质量控制处理。数据集包括站点位置、设备配置和观测方法等详细信息，适用于生态水文遥感研究。