This dataset provides the newly generated data associated with the article: Cao, Z.; Gao, H.; Nan, Z.*; Zhao, Y.; Yin, Z. A Semi-physical Approach for Downscaling Satellite Soil Moisture Data in a Typical Cold Alpine Area, Northwest China. Remote Sens. 2021.Three data are contained:• "ATI" is the apparent thermal inertia (ATI) estimated using MODIS LST and reflectance products over the Baoba River basin from April to November 2015; file names follow the convention "ATI2015XXX.tif", where "XXX" represents the day of year.• "DownsacledSM.gdb" is a geodatabase created by ArcGIS 10.7, which includes the downscaled 1km-resolution SMAP soil moisture from April to November 2015. Each raster file within the geodatabase is named with "SMAPDXXX", where "XXX" represents the day of year.• "QuantileMapping" includes the uncorrected downscaled SM and the one corrected by quantile mapping method at four WATERNET sites (IDs: 02, 11, 12, and 42) where large systematic errors exist between original SMAP data and the in-situ observation 4cm SM data. They are used in Figure 12 in the article.Point of Contact:Zhuotong Nan (giscn@msn.com)https://permalab.nanzt.info/