Land‐Atmosphere Cascade Fueled the 2020 Siberian Heatwave

A heatwave in Siberia starting January 2020, initiated by a wave 5 pattern the jet stream, caused surface air temperature to reach 38°C June with important impacts on ecosystems and water resources. Here we show that this dynamical setup started chain of events leading long-lasting unusual event: positive anomalies over early snowmelt, substantial earlier vegetation greening accompanied decreased soil moisture browning summer. This depletion browning, turn, increased impact atmosphere through land-atmosphere feedback. line evidence suggests large-scale dynamics interactions both contributed magnitude persistence record-breaking heatwave, addition background global warming mean temperature. Here, describe carry-over effect from spring anomaly into summer dryness retroaction atmosphere. With Arctic twice as fast average, event foreshadows future northern latitude continents emphasizes importance atmospheric climate changes. More frequent similar could have major consequences carbon cycle these carbon-rich regions.