 The Tibet OBS is a unique observatory designed to measure soil moisture and soil temperature on the Tibetan Plateau. This observatory consists of three regional scale in situ reference networks which provide a representative coverage of the different climate and land surface hydrometeorological conditions on the Tibetan Plateau. The aim of this study was to assess the reliability of several satellite products for the Naku and Makka network areas. The results showed that global course resolution soil moisture products are useful but exhibit till now unreported uncertainties in cold and semi-arid regions. Therefore, it is important to quantify and reduce these uncertainties by using in situ measurements. This article was authored by Zisu, J1, Eldente, and others.