The 2022 Record‐Breaking Northeastward Shift of South Asian High Since 1980: The Role of the Gulf Stream

Abstract

In August 2022, the South Asian High (SAH) deviated from its typical northwest–southeast displacement pattern and exhibited a record‐breaking northeastward shift over the period 1980–2024. Accompanying this displacement, a deep and persistent high‐pressure centre developed over mid‐latitude East Asia, directly leading to extreme heat over the Yangtze River Valley (YRV) in August 2022. Our results indicate that the northeastward shift of the SAH is significantly associated with the negative phase of the Silk Road Pattern (SRP) wave train that is a major atmospheric dynamical process over summer Eurasia. Compared with the weak cold sea surface temperature anomalies (SSTA) over the tropical Indian Ocean and Pacific, the unprecedented negative‐phase SRP played a more critical role in driving the shift of the SAH in August 2022. Furthermore, the strongest warming over the mid‐latitude North Atlantic contributed to triggering and maintaining the unprecedented negative‐phase SRP since 1980, ultimately facilitating the occurrence of the record‐breaking northeastward shift of the SAH in August 2022. The extreme warming in the mid‐latitude North Atlantic is attributed to the northward shift and strengthening of the Gulf Stream. This study provides a novel explanation of the linkage between the Gulf Stream and the northeastward shift of the SAH in August 2022 via the warming North Atlantic, which carries a potential source of predictability of the SAH location and climate change in East Asia.