Theoretical study of ice cover phenology at large freshwater lakes based on SMOS MIRAS data Vasiliy Tikhonov 1,2, Ilya Khvostov 3, Andrey Romanov 3, Evgeniy Sharkov 1 1Department of Earth Research from Space, Space Research Institute of the Russian Academy of 5 Sciences, 84/32 Profsoyuznaya Str., Moscow 117997, Russia 2Moscow Institute of Physics and Technology (State University), 9 Institutskiy Per., Dolgoprudny, Moscow Region 141701, Russia 3Institute for Water and Environmental Problems, Siberian Branch of the Russian Academy of Sciences, 1 Molodezhnaya Str., Barnaul 656038, Altai Krai, Russia 10 Correspondence to: Vasiliy Tikhonov (
[email protected]) Abstract. The paper presents a theoretical analysis of seasonal brightness temperature variations at a number of large freshwater lakes - Baikal, Ladoga, Great Bear Lake (GBL), Great Slave Lake (GSL), and Huron - retrieved from Microwave Imaging Radiometer with Aperture Synthesis (MIRAS) data (1.4 GHz) of the Soil Moisture and Ocean Salinity (SMOS) satellite. The analysis was performed using 15 the model of microwave radiation of plane layered heterogeneous nonisothermal medium. The input parameters for the model were real regional climatological characteristics and glaciological parameters of ice cover of the study lakes. Three distinct seasonal brightness temperature time regions corresponding to different phenological phases of the lake surfaces: complete ice cover, ice melt and deterioration, and open water, were revealed. The paper demonstrates the possibility to determine the 20 beginning of ice cover deterioration from satellite microwave radiometry data. The obtained results can be useful for setting the operating terms of winter crossings and roads on ice, since with the beginning of ice deterioration, these transportation routes across water bodies (rivers, lakes, water reservoirs) become insecure and cannot be used any more.