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This study investigates the relationship between sea surface temperature (SST) anomalies in the subtropical Atlantic Ocean, as represented by the Southern Atlantic subtropical dipole (SASD), and SST anomalies in the tropical Pacific Ocean, identified by the El Niño‐Southern Oscillation (ENSO). Contrary to the previously held notion of a weak relationship between SASD and ENSO as suggested by earlier literature, our analysis reveals a substantial inverse correlation between the two. This correlation exhibits significant multi‐decadal variability, which has notably intensified over the most recent two decades compared with the preceding two decades. This intensification in the SASD–ENSO inverse correlation may be attributed to the shift in ENSO regime from predominance of eastern Pacific El Niño to central Pacific El Niño events around the turn of the century. This transition triggers wavetrains that propagate along different paths, consequently influencing the South Atlantic subtropical high and inducing alterations in anomalous SST patterns in the subtropical Atlantic Ocean. These findings advance our comprehension of the interactions between South Atlantic and Pacific SST variations, which strongly influence rainfall patterns, particularly in South America and southern Africa. Understanding such teleconnection holds promise for improving sub‐seasonal to seasonal precipitation predictions in these regions. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between sea surface temperature (SST) in the subtropical Atlantic Ocean, as represented by the Southern Atlantic Subtropical Dipole (SASD), and SST in the tropical Pacific Ocean, identified by the El Niño-Southern Oscillation (ENSO). Our analysis reveals a significant inverse correlation between the SASD and Niño indices over a century, with multi-decadal variability that contradicts weak simultaneous correlations previously reported in the literature. The study also highlights a strengthening of their inverse correlations in the most recent two decades compared to the preceding two decades, which can be attributed to the shift in ENSO regime from more frequent eastern Pacific El Niño to central Pacific El Niño around the turn of the century. This shift helps set the stage for changes in convective activity in the critical region (20° S–40° S, 180°–140° W) of the central South Pacific Ocean, triggering wavetrains that propagate along different paths and ultimately contributing to different southern Atlantic subtropical high (SASH) and changes in anomalous SST patterns in the subtropical Atlantic Ocean. These findings advance our understanding of the interactions between South Atlantic and Pacific SST variations, which strongly influence rainfall patterns particularly in South America and southern Africa and may improve sub-seasonal to seasonal precipitation predictions in these regions. [ABSTRACT FROM AUTHOR]

This study presents different characteristics of precipitation and synoptic‐scale circulation associated with extreme precipitation events in inland and coastal Antarctica. The focus is on two stations, inland Vostok and coastal Casey. We use observed daily precipitation data from years 2004–2017 to investigate and compare the statistics on precipitation at both stations. The key areas for synoptic features favouring extreme precipitation are identified on the basis of air‐mass backward trajectories, computed applying the Lagrangian HYSPLIT model. The air moisture accounting for high‐precipitation events originates from the ocean but in many (some) cases the trajectories cover long distances over the ice sheet before reaching Vostok (Casey). Multiple statistical methods including composite analysis, empirical orthogonal functions (EOF), and self‐organizing maps (SOMs) are used to examine the full view of synoptic patterns. At Vostok in the inland high plateau, ERA‐Interim reanalysis shows that the synoptic patterns governing the extreme precipitation events are relatively complicated. Amplified planetary waves allow water vapour to reach the Vostok Station from different source regions, including the Weddell Sea, Ross Sea, and the Indian Ocean off the Amery Ice Shelf. A dipole structure of negative height anomalies to the west and positive ones to the east of the station is identified as the cause of southward water vapour transport and resulting precipitation at Casey in coastal Antarctica. [ABSTRACT FROM AUTHOR]