Remote sensing is an important tool for estimating essential climate variables (ECVs) that control the water and energy cycle (such as soil moisture, snow water equivalent, vegetation water content, surface temperature, radiation, and evapotranspiration). Over the last few decades, observations from space by active sensors (e.g. PALSAR, Radarsat, Sentinel, ASCAT, and SAOCOM) and passive sensors (e.g. SSM/I, AMSR, MODIS, GMI, SMOS, and SMAP) have enabled significant advances in many applications through measurement, forecast, modeling, and assimilation. Enhanced observation capability from future missions is expected to expand this trend and result in the further utility of remote sensing observations in current and new applications in water and energy cycles. This session seeks papers that contribute to 1) improving our understanding of modeling electromagnetics signals and their responses to changes in ECVs; 2) techniques for the retrieval of these ECVs using remote sensing observations; 3) field experiments for validation of satellite data products; 4) Application of remote sensing ECVs in water and energy cycle modeling.