The role of the North Atlantic Ocean on the increase in East Asia’s spring extreme hot day occurrences across the early 2000s

• Published in: Scientific reports Vol. 14; no. 1; p. 9872
• Main Authors: Lee, Yong-Han, Yeh, Sang-Wook, Kim, Jeong-Hun, Kim, Maeng-Ki
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 30.04.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 704/106; 704/106/35; 704/106/829; Atmospheric teleconnection; East Asia’s extreme hot day; High pressure; Humanities and Social Sciences; Linear baroclinic model; multidisciplinary; North Atlantic Tripole-like; Science; Science (multidisciplinary); Sea surface temperature; Temperature; Time series; East Asia; North Atlantic Tripole-like; East Asia’s extreme hot day; Linear baroclinic model; Atmospheric teleconnection
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-59812-y

The occurrence frequency of East Asia’s extreme hot day in boreal spring has increased since 1979. Using observational data and a Linear baroclinic model experiment, our study suggests that the occurrence of hot day is mainly due to anomalous high pressure over East Asia associated with a horizontal stationary wave train originating from a positive phase of the North Atlantic Tripole (NAT) sea surface temperature (SST) in spring. The effect of a positive phase of the NAT SST is evident in the 2000s, apparently associated with the linear trend of the North Atlantic SST like a positive phase of the NAT SST. Before 2000s, in contrast, SST forcing in the Indian Ocean and eastern tropical Pacific, which is associated with a negative phase of the NAT SST, may contribute to induce the East Asian hot days through atmospheric teleconnections. This implies that the relationship between a positive phase of the NAT SST and the occurrence of hot days in East Asia has been changed during the 2000s.