Interannual and interdecadal variations of sea surface temperature in the East Asian Marginal Seas

Abstract

Interannual and interdecadal variability of sea surface temperature (SST) in the East Asian Marginal Seas (EAMS) from 1951 to 1996 are investigated, and the teleconnection of the EAMS to the equatorial ocean is studied using empirical orthogonal function analysis and coherency analysis. The EAMS have significant coherency with the Niño 3.4 SST at 2- to 3-year periods with a phase lag of 5–9 months in the SST anomaly (SSTA). The EAMS also showed a higher coherency with a 6-year oscillation with a phase lag of 18–22 months. For the 6-year variability, the SSTA of the Niño 3.4 is highly coherent with the latent and sensible heat flux anomaly of the southern East Sea, indicating that the variability of the southern East Sea is related to that in the Niño 3.4 region through the ocean-atmosphere interactions. The southern East Sea also has a higher coherency with the East China Sea. Cooling in the southern East Sea and sudden warming in the northern East Sea were found to have occurred around 1965/1966 in the records of interdecadal variability. The decadal and interdecadal variabilities of the EAMS were found to be teleconnected to the western equatorial Pacific, whereas the interannual variability was highly correlated to the central equatorial Pacific, which is represented by Niño 3.4 SST.