Early burst of Tibetan Plateau vortices increases extreme precipitation over Tibetan Plateau in early spring

Tibetan Plateau vortices (TPVs) are key drivers of precipitation over the Tibetan Plateau (TP), triggering heavy precipitation both locally and in downstream regions. This work reveals that an early burst of TPVs significantly enhances the extreme precipitation over the TP in early spring. Variation in burst date of TPVs during 1979–2023 is investigated, and the underlying mechanism is explored. It is reported that the burst date of TPVs tends to be much earlier, gradually shifting from April to March. Rapid sea ice cover decline in the northern North Atlantic, under the sea surface warming context, intensifies the subsequent upward surface heat flux in the sea near Scandinavia. This process promotes the negative phase of Scandinavia teleconnection pattern (STP) in March, which benefits the genesis of TPVs by strengthening the cyclonic convergence and ascending motion over the TP.