报告摘要🏠👨🏻🦰:Soil moisture (ice or liquid) is essential to climate/weather forecast regarding water/energy exchange between the atmosphere and land surface. On a global scale, microwave remote sensing of soil moisture and the freeze/thaw state is a promising tool compared to other methods. ECMWF has a branch in the name of CMEM for assimilating microwave signals in its forecasting system. This report will present a short report about the progress and challenges in this topic, especially at L-band. Some examples of my on-going works, including soil moisture sensing depth, forwarding brightness simulation, frozen fraction detection, TSMP-PDAF (a coupled model developed by Julich, Germany) observation operator, will also be introduced to call for potential collaborators.