A team of scientists from the V.E. Zuev Institute of Atmospheric Optics SB RAS (Tomsk) and the Institute of Solar-Terrestrial Physics SB RAS (Irkutsk) predicts a nervous, contrasting winter in Siberia with alternating frosts and thaws. According to the researchers, such weather pattern stems from unstable atmospheric conditions, particularly within the stratosphere—a layer situated between 11 and 50 km above Earth's surface. Due to a sudden stratospheric warming event in November, the polar vortex – a giant ring of cold air rotating over the Arctic – has become destabilized.