Simultaneous with the satellite overpass, numerous ground data were collected, spectrum (ASD Fieldspec FRTM (Boulder, Co, USA), 350nm-2500nm, 3nm for the visible near-infrared band and 10nm for the shortwave infrared band), the surface temperature, atmospheric parameters, the soil profile gravimetric moisture (0-1cm, 1-3cm and 3-5cm), the shallow layer frost depth and the soil roughness in C1, G1, W1, W2, B1 and B2, mostly the grassland, the wheat stubble land, the deep plowed land and the rape stubble land. The quadrates of 90m×90m and 450m×450m were compartmentalized into 81 subgrids of 10m×10m and 50m×50m. Based on the resolution of 30m×30m and 150m×150m, the influence of adjacent eight pixels on the center pixel was studied. Section lines of each subgrid were adopted to acquire the pixel spectrum, which were measured more than once for the mean value.
The spectrum data were archived in the ASCII format, with the first five rows as the file header and the following two columns as wavelength (nm) and reflectance (percentage) respectively. The .txt file was not reflectance but intermediate file for further calculation. Raw data were binary files direct from ASD (by ViewSpecPro).
The surface radiative temperature and the physical temperature were measured by the handheld infrared thermometer. Besides, the cover type was also recorded. The data can be opened by Microsoft Office.
Atmospheric parameters were measured by CE318 to retrieve the total optical depth, aerosol optical depth, Rayleigh scattering coefficient, column water vapor in 936 nm, and various parameters at 550nm to obtain horizontal visibility with the help of MODTRAN or 6S. Those provide reliable data for atmosphere correction of the same period in this area.
The gravimetric soil moisture (samples from 0-1cm, 1-3cm and 3-5cm) was measured by the microwave drying method.
The frost depth by the chopstick and the ruler. The soil was considered frozen when it was hard and with ice crystal. The data can be opened by Microsoft Office.
Nine data files were included, TM data, CE318 data, B1, B2, C1, G1, W1 and W2.
Data Citation Zhang Lixin, Chang Sheng, Chang Yan, Fang Qian, Liang Xingtao, Liu Zhigang, Liu Chenzhou, Pan Jinmei, Peng Danqing, Qu Ying, Ren Huazhong, Yin Xiaojun, Zhang Yongpan, Zhang Zhiyu, Zhao Shaojie, Zhao Tianjie, Zheng Yue, Zhou Ji, Zhang Zhiyu.WATER: Dataset of ground truth measurements synchronizing with Landsat TM in the Biandukou foci experimental area on Mar. 17, 2008. Beijing Normal University; Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences; Institute of Remote Sensing Applications, Chinese Academy of Sciences. 2008. doi:10.3972/water973.0028.db
The dataset is generated from the "Watershed Airborne Telemetry Experimental Research (WATER) “, the user must have a clear statement in the article of the original data source and adopt the reference style providing by the metadata in the References section.