Connections between different characteristics of the Tibetan Plateau vortices

Abstract

AbstractTibetan Plateau vortices (TPVs) are major rainfall triggers over the Tibetan Plateau (TP), which often cause heavy rainfalls in eastern China when moving off the TP. Although previous studies have revealed the climatic characteristics of TPVs at different timescales, the relationships between the different activity characteristics of TPVs are unclear. In this study, TPVs during May to August during 1998–2020 are objectively identified based on ERA5 reanalysis data, and connections between the initial states of TPVs and their subsequent activities, as well as the connections between the states of TPVs before moving off the TP and those after moving off are investigated. It is reported that the TPVs generated over the central and western TP north of 32° N, particularly near 84° E, 35° N, are always stronger, maintain longer and move further in their subsequent life, and the TPVs generated near 95° E over the eastern TP move eastwards the fastest. The initial intensity of most TPVs is smaller than 1.1 × 10−4 s−1; regarding these TPVs, their average duration, movement distance and movement speed exhibit an initial decrease followed by an increase as the initial intensity rises. The stronger the TPVs initially are, the stronger they are in their entire lifetime. The majority of the moving‐off TPVs are generated over the eastern TP; generally, TPVs generated further east with a large initial intensity are more likely to move off the TP. After moving off the TP, most TPVs remain in the same movement direction as before; if the TPVs are strong when they are over the TP, they tend to be strong, last long and move eastwards further after moving off the TP, and vice versa.