Teleconnection associated with Variations in the Subarctic Circulation of North Pacific
Yoshihiko Sekine (Institute of Oceanography, Faculty of Bioresources Mie university, 1515 Kamihamachou, Tsu 514-8507, Japan)
e-mail:sekine@bio.mie-u.ac.jp
Abstract
INTRODUCTION
Anomalous southward shift of the Oyashio and the subarctic circulation in the North Pacific occurs in late winter to spring. Sekine (1988a; 1989) pointed out that prior to occurrences of the anomalous southward shift of the Oyashio and subarctic circulation in late winter to spring, the southward shift of the enhanced Aleutian Low is commonly observed in midwinter. In relation to this, southward shift of the latitude with no wind stress curl and increased Sverdrup transport of the subarctic circulation are also observed. On the basis of this observational evidence, Sekine (1988b) demonstrated numerically that the anomalous southward shift of the Oyashio and subarctic circulation is due to the barotropic response of the ocean to the change in the wind stress induced by the southward shift of the enhanced Aleusian Low. Yamada and Sekine (1997) showed by use of the EOF analysis of the observed height of 500 hPa and SST in the North Pacific that the cold SST in the subarctic circulation In winter to spring coincides with the southward shift of the enhanced Aleutian Low.
