Abstract

The spatiotemporal characteristics of the winter-to-winter recurrence (WWR) of sea surface temperature anomalies (SSTA) in the Northern Hemisphere (NH) are comprehensively studied through lag correlation analysis. On this basis the relationships between the SSTA WWR and the WWR of the atmospheric circulation
anomalies, El Nin˜ o–Southern Oscillation (ENSO), and SSTA interdecadal variability are also investigated.

Results show that the SSTAWWRoccurs over most parts of the North Pacific and Atlantic Oceans, but the spatiotemporal distributions of the SSTAWWRare distinctly different in these two oceans. Analyses indicate that the spatiotemporal distribution of the SSTA WWR in the North Atlantic Ocean is consistent with the spatial distribution of the seasonal cycle of its mixed layer depth (MLD), whereas that in the North Pacific Ocean, particularly the recurrence timing, cannot be fully explained by the change in the MLD between winter and summer in some regions. In addition, the atmospheric circulation anomalies also exhibit theWWR at the mid–high latitude of the NH, which is mainly located in eastern Asia, the central North Pacific, and the North Atlantic. The sea level pressure anomalies (SLPA) in the central North Pacific are essential for the occurrence of the SSTAWWRin this region.Moreover, the strongest positive correlation occurswhen the SLPA lead SSTAin the centralNorth Pacific by 1month, which suggests that the atmospheric forcing on the oceanmay play a dominant role in this region. Therefore, the ‘‘reemergence mechanism’’ is not the only process influencing the SSTA WWR, and theWWRof the atmospheric circulation anomalies may be one of the causes of the SSTAWWRin the central North Pacific. Finally, the occurrence of the SSTAWWRin the NH is closely related to SSTA interdecadal variability in the NH, but it is linearly independent of ENSO.