黑河综合遥感联合试验：阿柔加密观测区RPG-8CH-DP地基微波辐射计及地表实况观测数据集

本数据集为在阿柔加密观测区山前缓坡上进行的冻土积雪微波辐射计连续观测数据及同步测量的土壤温度/水分数据集。
2008-3-10下午在阿柔加密观测区，选取了较平整的一片被雪覆盖的土地，粗略地确定了辐射计的视场范围，辐射计高度离地面4.5米。以车头为方位角0度，顺时针240度观测冻土，270度观测积雪。其中，冻土以高度角-40度固定角度观测，积雪以高度角-20度至-70度观测。冻土视场为人工取出该区域表面积雪获得，去除得并不是很理想，土壤表层仍残留部分冰雪，至2008-3-11中午，冰雪基本融化完。
主要观测数据包括：表层土壤水分（微波炉烘干法获得重量含水量），土壤温度（热敏电阻）及植被状况观测。观测地点的表层有枯萎的干草覆盖，土壤有机质含量较高，土壤中草的根系较多。积雪厚度在10cm以下。 土壤温度采用的是热敏电阻，热敏电阻的电阻值反应温度变化，电阻值由数据采集仪自动记录。电阻值数据格式为DataTaker 数采仪专用格式，只能有该数采仪的专用软件打开。电阻值计算温度需要用特定热敏电阻的定标系数来计算。本数据所包含的是已经计算出来的土壤温度值。
亮温数据有两种格式：一种是仪器自带软件可以打开的格式，后缀为.BRT，需要用北京师范大学车载微波辐射计（TMMR：Truck Mounted Microwave Radiometer）自带软件打开，需要使用该软件的用户可以向该数据联系人索取；另外一种是文本文件（ASCII格式），可以用任何一种文本浏览软件打开。这两种文件格式中的数据是完全相同的。文本文件中按列依次为：年、月、日、时、分、秒、6.925GHz(h)、6.925GHz(v)、10.65GHz(h)、10.65GHz(v) 、18.7GHz(h)、18.7GHz(v)、36.5GHz(h)、36.5GHz(v)、高度角、方位角。由于6.925GHz和10.65GHz 的故障问题没有参加试验，故数据中，该四列的值均为0。

This dataset contains continuous microwave radiometer observation data and synchronously measured soil temperature and moisture data collected on the gentle piedmont slope of the Arou Intensive Observation Area.

On the afternoon of March 10, 2008, in the Arou Intensive Observation Area, a relatively flat snow-covered land plot was selected. The field of view of the microwave radiometer was roughly determined, with the radiometer mounted 4.5 meters above the ground. Taking the front of the vehicle as 0° azimuth, frozen soil was observed at 240° clockwise, and snow cover was observed at 270° clockwise. The frozen soil was observed at a fixed elevation angle of -40°, while the snow cover was observed at elevation angles ranging from -20° to -70°. The field of view for frozen soil was obtained by manually removing the surface snow in this area, but the removal was not thorough, with some residual ice and snow remaining on the topsoil. The residual ice and snow basically melted away by noon on March 11, 2008.

The main observation data include: surface soil moisture (gravimetric water content obtained via microwave drying method), soil temperature (measured via thermistors), and vegetation condition observations. The surface of the observation site was covered with withered hay, with high soil organic matter content and abundant grass roots in the soil. The snow thickness was less than 10 cm.

Soil temperature was measured using thermistors, whose resistance values reflect temperature changes, and the resistance values were automatically recorded by a data acquisition instrument. The resistance data is in the dedicated format of the DataTaker data acquisition instrument, and can only be opened with its dedicated software. Calculating temperature from the resistance values requires the calibration coefficients of the specific thermistors used. The soil temperature values included in this dataset have already been calculated.

There are two formats for the brightness temperature data: one is the format compatible with the instrument's built-in software, with the file suffix .BRT, which requires the dedicated software of the Truck-Mounted Microwave Radiometer (TMMR) developed by Beijing Normal University. Users in need of this software may request it from the data contact. The other format is a text file (ASCII format), which can be opened with any text browsing software. The data contained in these two file formats are completely identical. The columns in the text file are arranged in the following order: year, month, day, hour, minute, second, 6.925GHz(h), 6.925GHz(v), 10.65GHz(h), 10.65GHz(v), 18.7GHz(h), 18.7GHz(v), 36.5GHz(h), 36.5GHz(v), elevation angle, azimuth angle. Due to equipment malfunctions in the 6.925GHz and 10.65GHz channels, these two bands did not participate in the experiment, so the values in these four corresponding columns are all 0 in the dataset.