Mestas-Nunez, A. M. and A. J. Miller, 2006:

Interdecadal variability and climate change in the Eastern Tropical Pacific: A review.

Progress in Oceanography,69, 267-284.

Abstract. In this paper, we review interdecadal climatic variability in the Eastern Tropical (ETP) Ocean. This variability dominates the climatic fluctuations in the North Pacific on scales between ENSO and the centennial trend and is commonly referred to as the Pacific Decadal Oscillation or PDO. We include a historical overview and a summary of observational work that describes the surface, tropospheric and subsurface signatures of this variability. Descriptions of interdecadal variability are incomplete at best, mostly due to limitation in the observational record. We emphasize that the well-known "ENSO-like" pattern describing the PDO with a maximum along the equator may not be an accurate representation in the ETP. In the ETP, the SST maxima are displaced north and south of the equator, which has significant implications for the tropospherically driven circulations.
Several mechanisms have been proposed to explain the PDO. We review models and mechanisms which capture our present level of understanding of the problem. We conclude with a description of the longer-scale multi-decadal variability and the centennial trend. This paper is part of a comprehensive review of the oceanography of the Eastern Tropical Pacific.

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