Resonance in bidecadal and pentadecadal climate oscillations over the North Pacific: Role in climatic regime shifts, Geophys

• Main Author: Shoshiro Minobe
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1999
• Subjects: Pacific; aleutian low
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.452.2539; http://eprints2008.lib.hokudai.ac.jp/dspace/bitstream/2115/21813/1/1999grl_letter.pdf

Abstract. The roles of interdecadal oscillations in cli-matic regime shifts, which are observed as rapid strength changes in the Aleutian low in winter and spring sea-sons, have been analyzed. A regime shift results from simultaneous phase reversals between pentadecadal and bidecadal variations, which synchronize with one an-other at a relative period of three. The pentadecadal variation, which is observed in both winter and spring seasons, provides the basic timescale of regime shifts, while the bidecadal variation, which is observed only in winter, characterizes the rapidity of the shifts. A Monte-Carlo simulation has shown that the simultaneous phase reversals or resonance between the pentadecadal and bidecadal variations reflect a physical linkage between them and do not coincide accidentally. The role of this synchronization feature for assessing and predicting regime shifts is discussed.